phenylephrine-hydrochloride and Bacteremia

Nasal mupirocin has an important role to play in the prevention of Staphylococcus aureus infection by eliminating nasal carriage of this organism. Indeed, in many countries nasal mupirocin is one of the mainstays for controlling outbreaks of methicillin-resistant S. aureus. Eradication of nasal S. aureus with mupirocin has been shown to be effective in preventing postoperative infections in patients undergoing cardiothoracic surgery and in preventing exit-site infections in patients undergoing haemodialysis. It has been proposed that the use of mupirocin should be extended to other situations, such as the prevention of postoperative infections in patients undergoing implant surgery and the prevention of bacteraemias in high-risk patients. Clinical trials are needed to establish the efficacy of mupirocin in these situations. Both low-level and high-level resistance have been reported during treatment with nasal mupirocin. Low-level resistance does not represent a significant clinical problem but high-level resistance resulting from indiscriminate use may give grounds for concern. Further review of these issues is required. As with any antibiotic, mupirocin should be used judiciously, as part of an integrated programme of infection control.

Topics: Anti-Bacterial Agents; Bacteremia; Drug Resistance, Microbial; Humans; Methicillin Resistance; Mupirocin; Nose; Renal Dialysis; Staphylococcal Infections; Staphylococcus aureus; Surgical Wound Infection

Healthcare-associated infections pose a potentially fatal threat to patients worldwide and Staphylococcus aureus is one of the most common causes of healthcare-associated infections. S. aureus is a common commensal pathogen and a frequent cause of bacteremia, with studies demonstrating that nasal and blood isolates from single patients match more than 80% of the time. Here we report on a contemporary collection of colonizing isolates from those with methicillin-resistant S. aureus (MRSA) bloodstream infections to evaluate the diversity within hosts, and detail the clinical features associated with concomitant nasal colonization.. Swabs of the bilateral anterior nares were obtained from patients diagnosed with MRSA bacteremia. A single colony culture from the blood and an average of 6 colonies from the nares were evaluated for MRSA growth. For the nares cultures, we typed multiple isolates for staphylococcal protein A (spa) and derived the clonal complexes. Demographic and clinical data were obtained retrospectively from the electronic medical record system and analysed using univariate and multivariable regression models.. Over an 11-month period, 68 patients were diagnosed with MRSA bloodstream infection, 53 were swabbed, and 37 (70%) were colonized with MRSA in the anterior nares. We performed molecular typing on 213 nasal colonies. Spa types and clonal complexes found in the blood were also detected in the nares in 95% of the cases. We also found that 11% of patients carried more than one clone of MRSA in the nares. Male sex and history of prior hospitalization within the past 90 days increased odds for MRSA colonization.. The molecular epidemiological landscape of colonization in the setting of invasive disease is diverse and defining the interplay between colonization and invasive disease is critical to combating invasive MRSA disease.

Topics: Bacteremia; Carrier State; Cross Infection; Humans; Male; Methicillin-Resistant Staphylococcus aureus; Nose; Retrospective Studies; Staphylococcal Infections; Staphylococcus aureus

A 42-year-old woman with a history of acute myeloid leukaemia status postallogeneic stem cell transplant presented with fevers, altered mental status, pulmonary infiltrates and septic shock that further progressed to thrombocytopenia and purpura fulminans. Laboratory studies were consistent with a diagnosis of thrombotic thrombocytopenic purpura (TTP). Blood cultures grew

Topics: Adult; Anti-Bacterial Agents; Bacteremia; Ceftriaxone; Diagnosis, Differential; Female; Fibrinolytic Agents; Fingers; Gangrene; Glucocorticoids; Graft vs Host Disease; Humans; Immunologic Factors; Leukemia, Myeloid, Acute; Nose; Plasma Exchange; Pneumococcal Infections; Purpura Fulminans; Purpura, Thrombotic Thrombocytopenic; Rituximab; Shock, Septic; Single-Domain Antibodies; Stem Cell Transplantation; Toes

The association of the nasal microbiome with outcomes in surgical patients is poorly understood.. To characterize the composition of nasal microbiota in patients undergoing clean elective surgical procedures and to examine the association between characteristics of preoperative nasal microbiota and occurrence of postoperative infection.. Using a nested matched case-control design, 53 individuals who developed postoperative infection were matched (approximately 3:1 by age, sex, and surgical procedure) with 144 individuals who were not infected (ie, the control group). The 2 groups were selected from a prospective cohort of patients undergoing surgical procedures at 2 tertiary care university hospitals in Baltimore, Maryland, who were at high risk for postoperative infectious complications. Included individuals were aged 40 years or older; had no history of autoimmune disease, immunocompromised state, immune-modulating medication, or active infection; and were scheduled to undergo elective cardiac, vascular, spinal, or intracranial surgical procedure. Data were analyzed from October 2015 through September 2020.. Nasal microbiome cluster class served as the main exposure. An unsupervised clustering method (ie, grades of membership modeling) was used to classify nasal microbial samples into 2 groups based on features derived from 16S ribosomal RNA gene sequencing. The microbiome cluster groups were derived independently and agnostic of baseline clinical characteristics and infection status.. Composite of surgical site infection, bacteremia, and pneumonia occurring within 6 months after surgical procedure.. Among 197 participants (mean [SD] age, 64.1 [10.6] years; 63 [37.7%] women), 553 bacterial taxa were identified from preoperative nasal swab samples. A 2-cluster model (with 167 patients in cluster 1 and 30 patients in cluster 2) accounted for the largest proportion of variance in microbial profiles using grades of membership modeling and was most parsimonious. After adjusting for potential confounders, the probability of assignment to cluster 2 was associated with 6-fold higher odds of infection after surgical procedure (odds ratio [OR], 6.18; 95% CI, 3.33-11.7; P < .001) independent of baseline clinical characteristics, including nasal carriage of Staphylococcus aureus. Intrasample (ie, α) diversity was inversely associated with infectious outcome in both clusters (OR, 0.57; 95% CI, 0.42-0.75; P < .001); however, probability of assignment to cluster 2 was associated with higher odds of infection independent of α diversity (OR, 4.61; 95% CI, 2.78-7.86; P < .001).. These findings suggest that the nasal microbiome was an independent risk factor associated with infectious outcomes among individuals who underwent elective surgical procedures and may serve as a biomarker associated with infection susceptibility in this population.

Topics: Aged; Bacteremia; Cardiac Surgical Procedures; Case-Control Studies; Craniotomy; Elective Surgical Procedures; Female; Humans; Male; Microbiota; Middle Aged; Nose; Pneumonia; Postoperative Complications; Risk Assessment; Risk Factors; RNA, Ribosomal, 16S; Spinal Fusion; Staphylococcus aureus; Surgical Wound Infection; Vascular Surgical Procedures

Staphylococcus aureus frequently causes infections in outpatient and hospital settings and can present as a highly variable entity. Typical manifestations are endocarditis, osteoarticular infections or infection of implanted prostheses, intravascular devices or foreign bodies. A thorough diagnostic evaluation with early focus identification is mandatory to improve patient outcome.. We report a case of a 68-year old patient with a history of double allogeneic stem cell transplant for acute myeloid leukemia who developed a S. aureus bacteremia with dissemination, severe sepsis and lethal outcome due to nasal handkerchief packing after nose bleeding.. A thorough medical examination with further diagnostic work-up is most important in S. aureus blood stream infection to identify and eradicate the portal(s) of entry, to rule out endocarditis, to search for spinal abscesses, osteomyelitis or spondylodiscitis. Adherence to management guides for clinicians must be of major importance to achieve optimal quality of clinical care, and thus improve patient outcome.

Topics: Aged; Bacteremia; Cross Infection; Diagnosis, Differential; Fatal Outcome; Germany; Humans; Leukemia, Myeloid, Acute; Male; Nose; Staphylococcal Infections; Staphylococcus aureus; Stem Cell Transplantation; Transplantation, Homologous

Dialysis patients are frequently exposed to Staphylococcus aureus due to stays in dialysis centers, hospitals or rest homes. The hemodialysis vascular access is a potential entry site for S. aureus, in particular when using a central venous catheter (CVC) which increases the risk of sepsis compared to arteriovenous (AV) fistula. We prospectively followed a cohort of 86 hemodialysis patients from an outpatient dialysis center over 25 months analyzing S. aureus carrier status, S. aureus infection rates and mortality.. Demographic data and patients´ medical histories were collected and followed from all hemodialysis patients. Blood samples, nasal swabs and swabs from the hemodialysis vascular access site were taken every six months for a period of 25 months and tested for S. aureus. Strains were cultured and further characterized by spa PCR and microarray-based genotyping. Resulting data were compared with those from the general population.. In cross-sectional analyses, an average of 40% of hemodialysis patients were S. aureus carriers compared to 27% in the general population. Longitudinally, a total of 65% were S. aureus carriers: 16% were persistent carriers, 43% were intermittently colonized. The most common S. aureus lineage in the dialysis patient cohort was the clonal complex (CC) 8 and the spa type t008, while in the general population, the clonal complex CC30 dominates. During the study period, we observed six S. aureus-associated blood stream infections with one S. aureus attributable death. S. aureus carriers with an AV fistula were more densely colonized in the nasal mucosa compared to patients with a CVC. Overall mortality was lower for hemodialysis patients with a positive S. aureus carrier status compared to non-carriers (hazard ratio of 0.19).. Compared to the general population, hemodialysis patients were more frequently colonized with S. aureus and displayed both different S. aureus colonization densities as well as lineages, possibly explained by more frequent exposure to health care environments. The lower overall mortality in carriers compared to non-carriers is intriguing and will be investigated in detail in the future.. ISRCTN 14385893 , 2. October 2018, retrospectively registered.

Topics: Adult; Aged; Aged, 80 and over; Arteriovenous Shunt, Surgical; Bacteremia; Carrier State; Catheter-Related Infections; Cause of Death; Central Venous Catheters; Cross Infection; Cross-Sectional Studies; Female; Follow-Up Studies; Germany; Humans; Male; Methicillin-Resistant Staphylococcus aureus; Middle Aged; Nose; Prospective Studies; Renal Dialysis; Staphylococcal Infections; Time Factors; Young Adult

Biofilm production is an important virulence factor which allows staphylococci to adhere to medical devices. The principal component of biofilm is a "polysaccharide intercellular adhesin (PIA)" which is composed of a beta-1,6-N-acetylglucosamine polymer synthesized by an enzyme (N-acetylglucosamine transferase) encoded by the ica operon found on the bacterial chromosome. This operon is composed of four genes (A, B, C, and D), and a transposable element IS256. In this study, we aimed to determine the biofilm production characteristics of invasive/non-invasive staphylococcus isolates and different staphylococcus species. Biofilm production of 166 staphylococci was phenotypically investigated on Congo Red Agar (CRA); the presence of icaA, icaD and IS256 genes were investigated by polymerase chain reaction (PCR). 74 of the isolates (44.6%) were identified as methicillin resistant Staphylococcus aureus (MRSA), 25 (15.1%) as methicillin sensitive S.aureus (MSSA), 25 (37.3%) as Staphylococcus hominis, 20 (12%) as S.epidermidis, ten (15%) as Staphylococcus haemolyticus, nine (13.4%) as Staphylococcus capitis, two (3%) Staphylococcus saprophyticus and one (1.5%) as Staphylococcus warnerii. Of the MRSA strains, 52 were isolated from blood and 22 from nose; all MSSA strains were isolated from nose cultures. Coagulase-negative staphylococci (CoNS) strains were composed of invasive and non-invasive strains isolated from nose, catheter tip and blood cultures from patients with catheter. Production with CRA method was found to be statistically significant in invasive isolates (p< 0.001). It is concluded that; as the biofilm formation capacity of invasive isolates can cause refractory infections and the importance of carriage and hospital infections of these bacteria, it is important to prevent the spread of these isolates. A combination of phenotypic and genotypic tests is recommended for the investigation of biofilm formation in staphylococci. 40.3% of the CoNS isolates, and 85.8% of S.aureus isolates produced biofilm on CRA (p< 0.001) and with PCR method the ratio of carrying three genes was found to be statistically important in S.aureus when compared with CoNS. Carriage of three genes and biofilm formation capacity of invasive isolates can cause refractory infections and the importance of carriage and hospital infections of these bacteria, it is important to prevent the spread of these isolates. A combination of phenotypic and genotypic tests is recommended for the

Topics: Bacteremia; Biofilms; Carrier State; Catheters; Cross Infection; DNA Transposable Elements; Humans; N-Acetylglucosaminyltransferases; Nose; Operon; Polysaccharides, Bacterial; Staphylococcal Infections; Staphylococcus; Virulence

Chlorhexidine and mupirocin have been increasingly used in healthcare facilities to eradicate methicillin-resistant Staphylococcus aureus (MRSA) carriage. The aim of this study was to determine the prevalence and mechanisms of chlorhexidine and mupirocin resistance in MRSA from invasive infections and colonisation. MRSA isolates obtained from blood and nasal samples between 2012 and 2014 were analysed. Susceptibility to mupirocin was determined by disk diffusion and Etest and susceptibility to chlorhexidine by broth microdilution. The presence of mupA and qac (A/B and C) genes was investigated by PCR. Molecular typing was performed in high-level mupirocin-resistant (HLMR) isolates. Mupirocin resistance was identified in 15.6% of blood isolates (10.9% HLMR) and 15.1% of nasal isolates (12.0% HLMR). Presence of the mupA gene was confirmed in all HLMR isolates. For blood isolates, chlorhexidine minimum inhibitory concentrations (MICs) ranged from ≤0.125 to 4mg/L and minimum bactericidal concentrations (MBCs) from ≤0.125 to 8mg/L. In nasal isolates, chlorhexidine MICs and MBCs ranged from ≤0.125 to 2mg/L. The qacA/B gene was detected in 2.2% of MRSA isolates (chlorhexidine MIC range 0.25-2mg/L) and the qacC gene in 8.2% (chlorhexidine MIC range ≤0.125-1mg/L). The prevalence of qacC was 18.9% in HLMR isolates and 3.6% in mupirocin-susceptible isolates (P=0.009). Most of the HLMR isolates (97.1%) belonged to ST125 clone. These results suggest that chlorhexidine has a higher potential to prevent infections caused by MRSA. In contrast, mupirocin treatment should be used cautiously to avoid the spread of HLMR MRSA.

Topics: Anti-Bacterial Agents; Bacteremia; Carrier State; Chlorhexidine; Drug Resistance, Bacterial; Genes, Bacterial; Humans; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Mupirocin; Nose; Spain; Staphylococcal Infections

Topics: Abortion, Septic; Adult; Bacteremia; Critical Care; Disseminated Intravascular Coagulation; Escherichia coli; Escherichia coli Infections; Female; Humans; Nose; Pregnancy; Purpura Fulminans; Shock, Septic; Skin Diseases

Hospital-associated methicillin-resistant Staphylococcus aureus (MRSA) infections are frequently caused by predominant clusters of closely related isolates that cannot be discriminated by conventional diagnostic typing methods. Whole genome sequencing (WGS) and DNA microarray (MA) now allow for better discrimination within a prevalent clonal complex (CC). This single center exploratory study aims to distinguish invasive (blood stream infection) and non-invasive (nasal colonization) MRSA isolates of the same CC5 into phylogenetic- and virulence-associated genotypic subgroups by WGS and MA. A cohort of twelve blood stream and fifteen nasal MRSA isolates of CC5 (spa-types t003 and t504) was selected. Isolates were propagated at the same period of time from unrelated patients treated at the University of Saarland Medical Center, Germany. Rooted phylotyping based on WGS with core-genome single nucleotide polymorphism (SNP) analysis revealed two local clusters of closely related CC5 subgroups (t504 and Clade1 t003) which were separated from other local t003 isolates and from unrelated CC5 MRSA reference isolates of German origin. Phylogenetic subtyping was not associated with invasiveness when comparing blood stream and nasal isolates. Clustering based on MA profiles was not concordant with WGS phylotyping, but MA profiles may identify subgroups of isolates with nasal and blood stream origin. Among the new putative virulence associated genes identified by WGS, the strongest association with blood stream infections was shown for ebhB mutants. Analysis of the core-genome together with the accessory genome enables subtyping of closely related MRSA isolates according to phylogeny and presumably also to the potential virulence capacity of isolates.

Topics: Amino Acid Substitution; Bacteremia; Cluster Analysis; Genome, Bacterial; Genomics; High-Throughput Nucleotide Sequencing; Humans; Methicillin-Resistant Staphylococcus aureus; Nose; Oligonucleotide Array Sequence Analysis; Phylogeny; Polymorphism, Single Nucleotide; Staphylococcal Infections; Virulence

Intensive chemotherapy for pediatric acute myeloid leukemia incurs the risk of infectious complications, but the benefits of antibiotic prophylaxis remain unclear.. In the current study, among 103 children treated on the AML02 protocol between October 2002 and October 2008 at St. Jude Children's Research Hospital, the authors retrospectively assessed the effect of antibiotic prophylaxis on the frequency of febrile neutropenia, clinically or microbiologically confirmed infections (including bacteremia), and antibiotic resistance, as well as on the results of nasal and rectal surveillance cultures. Initially, patients received no prophylaxis or oral cephalosporin (group A). The protocol was then amended to administer intravenous cefepime alone or intravenous vancomycin plus either oral cephalosporin, oral ciprofloxacin, or intravenous cefepime (group B).. There were 334 infectious episodes. Patients in group A had a significantly greater frequency of documented infections and bacteremia (both P < .0001) (including gram-positive and gram-negative bacteremia; P = .0003 and .001, respectively) compared with patients in group B, especially viridans streptococcal bacteremia (P = .001). The incidence of febrile neutropenia without documented infection was not found to be different between the 2 groups. Five cases of bacteremia with vancomycin-resistant enterococci (VRE) occurred in group B (vs none in group A), without related mortality. Two of these cases were preceded by positive VRE rectal surveillance cultures.. Outpatient intravenous antibiotic prophylaxis is feasible in children with acute myeloid leukemia and reduces the frequency of documented infection but not of febrile neutropenia. Despite the emergence of VRE bacteremia, the benefits favor antibiotic prophylaxis. Creative approaches to shorten the duration of prophylaxis and thereby minimize resistance should be explored.

Topics: Administration, Oral; Adolescent; Anti-Bacterial Agents; Antibiotic Prophylaxis; Bacteremia; Bacterial Infections; Candidiasis; Cefepime; Cephalosporins; Chemotherapy-Induced Febrile Neutropenia; Child; Child, Preschool; Ciprofloxacin; Consolidation Chemotherapy; Drug Therapy, Combination; Feasibility Studies; Female; Humans; Incidence; Induction Chemotherapy; Infant; Infusions, Intravenous; Leukemia, Myeloid, Acute; Male; Neoplasm Staging; Nose; Outpatients; Rectum; Retrospective Studies; Treatment Outcome; Vancomycin; Young Adult

Topics: Aged; Anti-Bacterial Agents; Antibodies, Monoclonal, Murine-Derived; Antineoplastic Agents; Bacteremia; Bordetella; Bordetella Infections; Carrier State; Cellulitis; Drug Resistance, Bacterial; Drug Therapy, Combination; Humans; Lymphoma, Large B-Cell, Diffuse; Maintenance Chemotherapy; Male; Nose; Recurrence; Rituximab; Treatment Failure

The aim was to prospectively describe the colonization pattern of coagulase-negative staphylococci (CoNS) and the relationship between colonizing and invasive CoNS isolates among patients undergoing treatment for hematological malignancy. Fourteen newly diagnosed patients were included with either multiple myeloma or acute leukemia. Patients were repeatedly sampled from nares, throat, axillae, and perineum, and the CoNS isolates obtained were phenotypically characterized together with blood isolates of CoNS using the PhenePlate system (PhP). During the treatment a gradual reduction in the heterogeneity of colonizing CoNS was observed as well as an inter-patient accumulation of phenotypically related and multi-drug-resistant CoNS. These clusters of CoNS persisted for 2-3 months after the end of therapy. Ten positive blood cultures of CoNS were obtained and in the majority of these cases CoNS of the same PhP type were found in superficial cultures collected prior to the blood culture sampling. In conclusion, the study shows that therapy for hematological malignancy is associated with a homogenization of colonizing CoNS isolates and that this acquired flora of CoNS is persistent several months after the end of therapy. Furthermore, the results suggest that the source of bloodstream infections of CoNS in hematological patients is colonizing CoNS of the skin and mucosa.

Topics: Adolescent; Adult; Aged; Axilla; Bacteremia; Bacterial Typing Techniques; Carrier State; Cluster Analysis; Coagulase; Drug Resistance, Multiple, Bacterial; Hematologic Neoplasms; Humans; Middle Aged; Nose; Perineum; Pharynx; Phenotype; Prospective Studies; Staphylococcal Infections; Staphylococcus; Young Adult

We examined the relationship between the use of nasal continuous positive airway pressure (CPAP) and nasal colonization among low-birth-weight (LBW) infants. We prospectively cultured the nares of LBW infants on admission and weekly until hospital discharge. The modality of respiratory support during each culture was recorded. Bivariate and multivariate analyses were conducted to test the relationship between CPAP and nasal colonization. Analyses were repeated after stratifying infants into three birth-weight categories: 1500 to 2499 g, 1000 to 1499 g, and < 1000 g. In total, 766 nasal cultures were obtained from 167 infants. Nasal colonization with gram-negative bacilli was increased with the use of CPAP in all birth-weight categories ( P < 0.05) and with vaginal delivery in infants weighing < 1000 g and 1500 to 2499 g ( P = 0.04 and P = 0.02, respectively). Nasal colonization with any potential pathogen increased with the use of CPAP in all birth-weight categories ( P < 0.001), with the presence of chorioamnionitis in infants < 1000 g ( P = 0.055) and at younger gestational age in infants 1000 to 1499 g ( P = 0.0026). Caucasian infants 1500 to 2499 g had less colonization than infants of other races ( P = 0.01). Nasal CPAP is associated with increased colonization with gram-negative bacilli.

Topics: Bacteremia; Chorioamnionitis; Colony Count, Microbial; Continuous Positive Airway Pressure; Delivery, Obstetric; Female; Gestational Age; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Incidence; Infant, Low Birth Weight; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Logistic Models; Male; Nose; Pregnancy; Prospective Studies; Staphylococcal Infections; Staphylococcus aureus

In the hemodialysis population, the incidence of Staphylococcus aureus colonization has been documented to be as high as 80%; effective prophylaxis of vascular access infection and bacteremia is a worthwhile goal in the management of hemodialysis population. Surveillance of 50 hemodialysis patients for S. aureus-positive nasal cultures was performed by monthly nasal swabs over a 12-month period. All patients were performing dialysis using hemodialysis catheters thrice weekly. All positive cultures were treated with a prophylactic antibiotic regimen. Thirty-one patients (62%) had one or more positive cultures. The surveillance period was longer in the S. aureus nasal carriers (p < 0.01). The frequency of positive cultures correlated with the duration of surveillance (p < 0.05). The incidence of S. aureus bacteremia was greater in patients with three or more positive cultures (p < 0.05). This study suggests that continuous surveillance for S. aureus nasal colonization is essential to properly identify all hemodialysis patients using catheters at risk of developing S. aureus bacteremias.

Topics: Adult; Anti-Bacterial Agents; Bacteremia; Catheters; Catheters, Indwelling; Equipment Contamination; Female; Humans; Male; Middle Aged; Nose; Renal Dialysis; Staphylococcal Infections; Staphylococcus aureus

Most Staphylococcus aureus small-colony variants (SCVs) are auxotrophs for menadione, hemin, or thymidine but rarely for CO(2). We conducted a prospective investigation of all clinical cases of CO(2)-dependent S. aureus during a 3-year period. We found 14 CO(2)-dependent isolates of S. aureus from 14 patients that fulfilled all requirements to be considered SCVs, 9 of which were methicillin resistant. The clinical presentations included four cases of catheter-related bacteremia, one complicated by endocarditis; two deep infections (mediastinitis and spondylodiscitis); four wound infections; two respiratory infections; and two cases of nasal colonization. Pulsed-field gel electrophoresis typing showed that the 14 isolates were distributed into 4 types corresponding to sequence types ST125-agr group II (agrII), ST30-agrIII, ST34-agrIII, and ST45-agrI. An array hybridization technique performed on the 14 CO(2)-dependent isolates and 20 S. aureus isolates with normal phenotype and representing the same sequence types showed that all possessed the enterotoxin gene cluster egc, as well as the genes for alpha-hemolysin and delta-hemolysin; biofilm genes icaA, icaC, and icaD; several microbial surface components recognizing adhesive matrix molecules (MSCRAMM) genes (clfA, clfB, ebh, eno, fib, ebpS, sdrC, and vw); and the isaB gene. Our study confirms the importance of CO(2)-dependent SCVs of S. aureus as significant pathogens. Clinical microbiologists should be aware of this kind of auxotrophy because recovery and identification are challenging and not routine. Further studies are necessary to determine the incidence of CO(2) auxotrophs of S. aureus, the factors that select these strains in the host, and the genetic basis of this type of auxotrophy.

Topics: Aged; Bacteremia; Bacterial Typing Techniques; Carbon Dioxide; Carrier State; Catheter-Related Infections; Discitis; DNA Fingerprinting; Electrophoresis, Gel, Pulsed-Field; Endocarditis, Bacterial; Genotype; Humans; Male; Mediastinitis; Microarray Analysis; Middle Aged; Nose; Respiratory Tract Infections; Staphylococcal Infections; Staphylococcus aureus; Virulence Factors; Wound Infection

In this study, we investigated the genetic background of 70 Staphylococcus aureus isolates (36 methicillin-resistant S. aureus [MRSA] and 34 methicillin-susceptible S. aureus [MSSA]) obtained from blood at a Korean tertiary-care hospital, using spa typing, multilocus sequence typing, and SCCmec typing. In addition, the prevalence of enterotoxin (sea, seb, sec, sed, see, seg, seh, sei, and sek), tst, and pvl genes among the samples was assessed via polymerase chain reaction, and the results were compared with those of 95 isolates of S. aureus obtained from nasal swabs. All MRSA isolates from blood, except one, belonged to three major clones: sequence type (ST)5-MRSA-II, ST72-MRSA-II (or IVA), and ST239-MRSA-III, among which ST5-MRSA-II was the predominant clone. The prevalence of enterotoxin genes in the S. aureus isolates obtained from blood differed significantly from those from the nasal swabs for the sea, seb, sec, and seh gene. In particular, the seb and sec genes were detected exclusively in the MRSA isolates of ST5 or spa-CC002, thereby suggesting the co-adaptation of virulence genes with the genetic background and their contribution to biological fitness.

Topics: Bacteremia; Enterotoxins; Genotype; Hospitals; Humans; Korea; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Nose; Staphylococcal Infections; Staphylococcus aureus

This study aimed to establish the feasibility and cost-effectiveness of rapid molecular screening for hospital-acquired meticillin-resistant Staphylococcus aureus (MRSA) in surgical patients within a teaching hospital.. In 2006, nasal swabs were obtained before surgery from all patients undergoing elective and emergency procedures, and screened for MRSA using a rapid molecular technique. MRSA-positive patients were started on suppression therapy of mupirocin nasal ointment (2 per cent) and undiluted chlorhexidine gluconate bodywash.. A total of 18,810 samples were processed, of which 850 (4.5 per cent) were MRSA positive. In comparison to the annual mean for the preceding 6 years, MRSA bacteraemia fell by 38.5 per cent (P < 0.001), and MRSA wound isolates fell by 12.7 per cent (P = 0.031). The reduction in MRSA bacteraemia and wound infection was equivalent to a saving of 3.78 beds per year (276,220 pounds sterling), compared with the annual mean for the preceding 6 years. The cost of screening was 302,500 pounds sterling, making a net loss of 26,280 pounds sterling. Compared with 2005, however, there was a net saving of 545,486 pounds sterling.. Rapid MRSA screening of all surgical admissions resulted in a significant reduction in staphylococcal bacteraemia during the screening period, although a causal link cannot be established.

Topics: Bacteremia; Cost-Benefit Analysis; Cross Infection; Elective Surgical Procedures; Emergency Treatment; Humans; Methicillin Resistance; Nose; Patient Compliance; Polymerase Chain Reaction; Specimen Handling; Staphylococcal Infections; Staphylococcus aureus; Surgery Department, Hospital; Surgical Wound Infection

Staphylococcus aureus is both a successful human commensal and a major pathogen. The elucidation of the molecular determinants of virulence, in particular assessment of the contributions of the genetic background versus those of mobile genetic elements (MGEs), has proved difficult in this variable species. To address this, we simultaneously determined the genetic backgrounds (spa typing) and the distributions of all 19 known superantigens and the exfoliative toxins A and D (multiplex PCR) as markers for MGEs. Methicillin- sensitive S. aureus strains from Pomerania, 107 nasal and 88 blood culture isolates, were investigated. All superantigen-encoding MGEs were linked more or less tightly to the genetic background. Thus, each S. aureus clonal complex was characterized by a typical repertoire of superantigen and exfoliative toxin genes. However, within each S. aureus clonal complex and even within the same spa type, virulence gene profiles varied remarkably. Therefore, virulence genes of nasal and blood culture isolates were separately compared in each clonal complex. The results indicated a role in infection for the MGE harboring the exfoliative toxin D gene. In contrast, there was no association of superantigen genes with bloodstream invasion. In summary, we show here that the simultaneous assessment of virulence gene profiles and the genetic background increases the discriminatory power of genetic investigations into the mechanisms of S. aureus pathogenesis.

Topics: Adult; Aged; Bacteremia; Bacterial Proteins; Blood; Carrier State; DNA, Bacterial; Female; Germany; Humans; Male; Middle Aged; Molecular Sequence Data; Nose; Sequence Analysis, DNA; Staphylococcal Infections; Staphylococcus aureus; Superantigens; Virulence Factors

The impact of bacterial clonality on infections caused by Staphylococcus aureus is unclear.. Three hundred seventy-nine S. aureus isolates (125 methicillin-resistant S. aureus [MRSA] and 254 methicillin-susceptible S. aureus [MSSA]) were genotyped by spa typing and multilocus sequence typing. For MRSA isolates, the staphylococcal chromosomal cassette mec (SCCmec) element was also typed. Three clinical categories were identified: nasal carriage only (n=118), uncomplicated infection (n=104), and bacteremia with hematogenous complications (n=157).. By use of eBURST, 18 clonal complexes (CCs) were found in 371 isolates. Eight CCs accounted for 89% of isolates and occurred in all clinical categories. CC5 (P=.0025) and CC30 (P=.0308) exhibited a significant trend toward more frequent hematogenous complications. Isolates within spa types 2 and 16 showed the same significant trend and grouped within CC5 and CC30, respectively. SCCmec II isolates also showed the same significant trend compared with SCCmec IV; 96% were CC5 or CC30.. Although most S. aureus genotypes exhibited the capacity to cause invasive disease, strains within CC5 and CC30 exhibited a significant trend toward increasing levels of hematogenous complications. Isolates within these CCs were also implicated by use of spa and SCCmec typing. The genetic determinants underlying these findings remain to be demonstrated.

Topics: Adolescent; Adult; Anti-Bacterial Agents; Bacteremia; Carrier State; Child; Genotype; Humans; Methicillin Resistance; Middle Aged; Nose; Staphylococcal Infections; Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen that causes severe morbidity and mortality in many hospitals worldwide, and MRSA infections are frequent in intensive care units (ICUs).. A prospective study was implemented to investigate the risk factors for ICU-acquired MRSA infections.. This study was conducted in surgical and neurologic ICUs from May to November 2003. The patients staying in ICUs more than 48 hours were included in the study. All of the patients were visited daily, and data were recorded on individual forms for each patient until discharge or death. Nasal swab cultures were done within 48 hours of ICU admission and repeated every week until the patients colonized with MRSA or were discharged from ICUs. ICU-acquired MRSA infection was diagnosed when MRSA was isolated from the infected site.. Overall, 249 patients were followed during the study. MRSA infection was detected in 21 (8.4%) of these patients. The most frequent infection was primary bloodstream infection (10/21, 47%). It was followed by pneumonia (8/21, 38%) and surgical site infection (3/21, 14%). Nasal MRSA colonization was detected in 59 (23.7%) patients, and 12 of them (20.3%) developed MRSA infection. In univariate analysis, hospitalization period in an ICU, intraabdominal and orthopedic pathologies, mechanical ventilation, central venous catheter insertion, total parenteral nutrition, previous antibiotic use, surgical ICU stay, nasal MRSA colonization, and presence of more than 2 patients having nasal colonization in the same ICU at the same time were found significant for MRSA infections. In multivariate analysis; hospitalization period in an ICU (OR, 1.090; 95% CI: 1.038-1.144, P = .001), central venous catheter insertion (OR, 1.822; 95% CI: 1.095-3.033, P = .021), previous antibiotic use (OR, 2.337; 95% CI: 1.326-4.119, P = .003) and presence of more than 2 patients having nasal colonization in the same ICU at the same time (OR, 1.398; 95% CI: 1.020-1.917, P = .037) were independently associated with MRSA infections.. According to the our results, hospitalization period in an ICU, presence of patients colonized with MRSA in the same ICU at the same time, previous antibiotic use, and central venous catheter insertion are independent risk factors for ICU-acquired MRSA infections. Detection of these factors helps to decrease the rate of MRSA infections in the ICUs.

Topics: Adult; Aged; Anti-Bacterial Agents; Bacteremia; Catheterization; Cross Infection; Female; Humans; Intensive Care Units; Length of Stay; Male; Methicillin Resistance; Middle Aged; Multivariate Analysis; Nose; Parenteral Nutrition; Pneumonia; Prospective Studies; Respiration, Artificial; Risk Factors; Staphylococcal Infections; Staphylococcus aureus; Surgical Wound Infection

We conducted this study to assess the rate of methicillin-resistant Staphylococcus aureus colonization and its association with infection among infants hospitalized in methicillin-resistant S aureus-endemic NICUs.. Between March 2003 and February 2004, surveillance culture specimens from the nares, postauricular areas, axillae, and umbilicus of infants admitted to the NICUs at a children's hospital in Taiwan were obtained weekly for the detection of methicillin-resistant S aureus. All colonized and clinical isolates from each study infant with methicillin-resistant S aureus infection were genotyped with pulsed-field gel electrophoresis, with Sma1 digestion, and compared.. A total of 783 infants were included in this study. Methicillin-resistant S aureus colonization was detected for 323 infants during their NICU stays, with detection with the first 2 samples for 89%. Nares and umbilicus were the 2 most common sites of initial colonization. Methicillin-resistant S aureus colonization was associated significantly with premature birth (< or = 28 weeks) and low birth weight (< or = 1500 g), and infants with colonization had a significantly higher rate of methicillin-resistant S aureus infection, compared with those without colonization (26% vs 2%). Methicillin-resistant S aureus colonization was noted for 84 of 92 infants with methicillin-resistant S aureus infections. Of the 68 episodes with previous colonization and isolates available for genotyping analysis, colonized and clinical isolates were indistinguishable in 63 episodes, highly related in 2 episodes, and distinct in 3 episodes.. More than 40% of the hospitalized infants were colonized with methicillin-resistant S aureus during their stay in methicillin-resistant S aureus-endemic NICUs; this was associated significantly with methicillin-resistant S aureus infection. Most infants with methicillin-resistant S aureus infections had previous colonization with an indistinguishable strain.

Topics: Axilla; Bacteremia; Bacterial Typing Techniques; Birth Weight; Carrier State; Cross Infection; DNA, Bacterial; Ear, External; Female; Gestational Age; Hospitals, Pediatric; Hospitals, University; Humans; Infant; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Intensive Care Units, Neonatal; Male; Methicillin Resistance; Nose; Patient Isolation; Skin; Sputum; Staphylococcal Infections; Staphylococcus aureus; Taiwan; Umbilicus

Topics: Bacteremia; Decontamination; Humans; Nose; Povidone-Iodine; Premedication; Preoperative Care; Radionuclide Imaging; Rhinoplasty; Surgical Wound Infection

Staphylococcus aureus remains a leading cause of food-poisoning with substantial impact on public health. Using a multiplex polymerase chain reaction-DNA enzyme immunoassay (PCR-DEIA), we studied the presence of genes encoding staphylococcal enterotoxin-like (SEl) superantigens sem, sen, and seo, associated with the enterotoxin gene cluster (egc), in 429 clinical Staphylococcus aureus isolates. 294 (68.5%) isolates tested positive for at least one of the three SEl genes. In contrast to the fixed gene combination seg/sei also located on egc, a substantial number of isolates (n = 108) were found to bear only one or two of the genes encoding SElM, SElN, and SElO. Regarding the origin of the S. aureus isolates, a significant difference (P = 0.022) was found for the possession of seo (61.2% of blood isolates versus 42.9% of nasal strains). Also sem (not significantly) was found more common in blood isolates (52.1% versus 40.5%). The survey of the newly described SEl genes sem-seo supports the concept that most clinical S. aureus isolates harbor subsets of pyrogenic toxin superantigens. The potential contribution of seo and sem to the pathogenic potential of S. aureus has to be further evaluated.

Topics: Bacteremia; DNA, Bacterial; Enterotoxins; Humans; Immunoenzyme Techniques; Nose; Polymerase Chain Reaction; Staphylococcus aureus

Because of their biofilm-forming capacity, invasive Staphylococcus epidermidis isolates, which cause the majority of nosocomial catheter-related bloodstream infections (BSIs), are thought to be selected at the time of catheter insertion from a population of less virulent commensal strains. This fact allows the prediction that invasive and contaminating strains can be differentiated via detection of virulence-associated genes. However, the hospital environment may pave the way for catheter-related infections by promoting a shift in the commensal bacterial population toward strains with enhanced virulence. The distribution of virulence-associated genes (icaADBC, aap, atlE, bhp, fbe, embp, mecA, IS256, and IS257), polysaccharide intercellular adhesin synthesis, and biofilm formation were investigated in S. epidermidis strains from independent episodes of catheter-related BSIs in individuals who have received bone marrow transplantation (BMT). The results were compared with those obtained for commensal S. epidermidis isolates from hospitalized patients after BMT and from healthy individuals, respectively. The clonal relationships of the strains were investigated by pulsed-field gel electrophoresis. icaADBC, mecA, and IS256 were significantly more prevalent in BSI isolates than in commensal isolates from healthy individuals. However, the prevalence of any of the genes in clonally independent, endogenous commensal strains from BMT patients did not differ from that in invasive BSI strains. icaADBC and methicillin resistance, factors important for the establishment of catheter-related infections, already ensure survival of the organisms in their physiological habitat in the hospital environment, resulting in a higher probability of contamination of indwelling medical devices with virulent S. epidermidis strains. The dynamics of S. epidermidis populations reveal that detection of icaADBC and mecA is not suitable for discriminating invasive from contaminating S. epidermidis strains.

Topics: Adolescent; Adult; Aged; Bacteremia; Bacterial Proteins; Bone Marrow Transplantation; Catheterization, Central Venous; Child; Child, Preschool; Electrophoresis, Gel, Pulsed-Field; Female; Humans; Male; Middle Aged; Nose; Staphylococcal Infections; Staphylococcus epidermidis; Virulence

A total of 429 different Staphylococcus aureus isolates encompassing 219 blood isolates and 210 isolates taken from anterior nares were systematically searched by two multiplex PCR-DNA enzyme immunoassays (PCR-DEIA) for exfoliative toxin (ET) genes eta and etb, as well as for the classical members of the pyrogenic toxin superantigen (PTSAg) gene family comprising the staphylococcal enterotoxin (SE) genes sea-see and the toxic shock syndrome toxin 1 gene tst. In addition, a third PCR-DEIA was established to investigate the possession of four recently described SE genes, viz. seg-sej. The most frequent PTSAg/ET genes amplified were seg and sei, which were found strictly in combination in 55.0% of the S. aureus isolates tested. Other frequently detected toxin genes were tst (20.3%), sea (15.9%), and sec (11.2%). Only five isolates harbored ET genes. Regarding the origin of the S. aureus isolates, a significant difference (P = 0.037) was found for the possession of the sed/sej gene combination (10.5% of blood isolates versus 3.3% of nasal strains). Overall, about half of S. aureus isolates tested harbored genes of the classical members of the PTSAg family and ETs (50.8%), whereas 73.0% of S. aureus isolates were toxin gene positive if the recently described SE genes were included. This notable higher prevalence indicates that the possession of PTSAg genes in particular seems to be a habitual feature of S. aureus. Moreover, mainly due to the fixed combinations of seg plus sei, as well as sed plus sej, the possession of multiple PTSAg genes (62.9%) is more frequent than assumed so far.

Topics: Bacteremia; Bacterial Proteins; Blood; DNA, Bacterial; Enterotoxins; Exfoliatins; Humans; Immunoenzyme Techniques; Nose; Polymerase Chain Reaction; Staphylococcal Infections; Staphylococcus aureus; Superantigens

The consequences of infection with Staphylococcus aureus can be severe, so strategies for prevention are important. We examined S. aureus isolates from blood and from nasal specimens to determine whether the organisms in the bloodstream originated from the patient's own flora.. In a multicenter study, swabs for culture were obtained from the anterior nares of 219 patients with S. aureus bacteremia. A total of 723 isolates were collected and genotyped. In a second study, 1640 S. aureus isolates from nasal swabs were collected over a period of five years and then compared with isolates from the blood of patients who subsequently had S. aureus bacteremia.. In the multicenter study of S. aureus bacteremia, the blood isolates were identical to those from the anterior nares in 180 of 219 patients (82.2 percent). In the second study, 14 of 1278 patients who had nasal colonization with S. aureus subsequently had S. aureus bacteremia. In 12 of these 14 patients (86 percent), the isolates obtained from the nares were clonally identical to the isolates obtained from blood 1 day to 14 months later.. A substantial proportion of cases of S. aureus bacteremia appear to be of endogenous origin since they originate from colonies in the nasal mucosa. These results provide support for strategies to prevent systemic S. aureus infections by eliminating nasal carriage of S. aureus.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Bacteremia; Bacterial Typing Techniques; Carrier State; Child; Child, Preschool; Cross Infection; Electrophoresis, Gel, Pulsed-Field; Female; Germany; Hospitals, Community; Hospitals, General; Humans; Infant; Male; Methicillin Resistance; Middle Aged; Nose; Staphylococcal Infections; Staphylococcus aureus

Topics: Bacteremia; Carrier State; Cross Infection; Methicillin Resistance; Nose; Staphylococcal Infections; Staphylococcus aureus

Topics: Bacteremia; Carrier State; Humans; Methicillin Resistance; Nose; Skin; Staphylococcal Infections; Staphylococcal Skin Infections; Staphylococcus aureus

Topics: Bacteremia; Cost-Benefit Analysis; Humans; Mass Screening; Nose; Staphylococcal Infections; Staphylococcus aureus

The mean biofilm production of 22 Staphylococcus epidermidis isolates associated with catheter related bacteremia was significantly higher than that of 32 nose isolates from healthy individuals. This difference was due to seven catheter related isolates. These findings do not show a clear association between biofilm production and virulence.

Topics: Bacteremia; Bacterial Typing Techniques; Biofilms; Catheterization; Humans; Nose; Prosthesis-Related Infections; Staphylococcus epidermidis

Staphylococcus aureus bacteremia (SAB) acquired in hospitals continues to be a frequent and serious complication to hospitalization, and no previous case-control studies dealing with risk factors of this severe disease are available.. Based on a 1-year prospective analysis, the data from all patients with hospital-acquired SAB admitted to 4 hospitals in Copenhagen County, Denmark, from May 1, 1994, through April 30, 1995, were evaluated. Eighty-five patients with hospital-acquired SAB were matched to 85 control patients with a similar primary diagnosis at admission (matched controls). Of these, 62 patients with hospital-acquired SAB were compared with 118 other patients with a similar time of admission, who were randomly selected with no clinical evidence of SAB (unmatched controls).. The incidence of hospital-acquired SAB was 0.71 per 1000 hospital admissions. The presence of a central venous catheter (odds ratio, 6.9; 95% confidence interval [CI], 2.8-17.0), anemia (odds ratio, 3.3; 95% CI, 1.4-7.6), and hyponatremia (odds ratio, 3.3; 95% CI, 1.5-7.0) was significantly associated with hospital-acquired SAB in a conditional and a usual logistic regression analysis. Nasal carriage was not an independent risk factor, but nasal carriers among patients in surgery (odds ratio, 4.0; 95% CI, 1.3-13.0) had a significantly higher risk for hospital-acquired SAB compared with matched and unmatched controls. The presence of hospital-acquired SAB increased the mortality rate 2.4-fold (95% CI, 1.1-5.2).. The presence of a central venous catheter is an important risk factor, and hyponatremia and anemia are associated with the development of hospital-acquired SAB. Furthermore, hospital-acquired SAB in itself increases mortality.

Topics: Adolescent; Adrenal Cortex Hormones; Adult; Age Factors; Aged; Aged, 80 and over; Anemia; Anti-Bacterial Agents; Bacteremia; Case-Control Studies; Catheterization, Central Venous; Child; Child, Preschool; Cross Infection; Denmark; Female; Hospitals, Community; Humans; Hyponatremia; Immunocompromised Host; Infant; Infusions, Intravenous; Male; Middle Aged; Nose; Odds Ratio; Prospective Studies; Regression Analysis; Renal Dialysis; Risk Factors; Sex Factors; Staphylococcal Infections; Staphylococcus aureus; Surgical Procedures, Operative; Survival Analysis; Transfusion Reaction

The staphylococcal scalded skin syndrome (SSSS) is due to exfoliative toxins A or B excreted by some strains of Staphylococcus aureus. This syndrome is exceptional in the first hours of life. We report a case of SSSS due to materno-fetal infection.. At 31 weeks of pregnancy a 40-year-old mother was febrile (39 degrees C) and a premature rupture of the amniotic sac occurred the following day. SSSS was diagnosed at 6 hours of life in the newborn, a 1760 g female. Staphylococcus aureus grew on the blood and vaginal bacterial cultures of the mother, as well as, from cultures of skin, nose, throat, and umbilical catheter in the newborn. The strains of Staphylococcus aureus isolated in the mother and the child had identical characteristic antibiotype and genotype by Random-PCR. The genes for both exfoliations A and B were present. Epidermization was rapidly obtained and no septicemia or septic complication was noted.. Staphylococcus aureus is usually responsible for nosocomial infections which occur in the early newborn period. In most cases, the infection is transmitted by a carrier who manipulates the child (family, visitors, nurse or medical staff). In our case, onset of SSSS early after birth suggested a perinatal transmission, due to lower genital tract infection in the mother. The presence of SSSS in the child and not in the mother may be explained by a massive perinatal infection and low elimination of the toxin in the newborn resulting in higher concentrations of exfoliative toxins in the blood.

Topics: Adult; Anti-Bacterial Agents; Bacteremia; Catheterization, Peripheral; Exfoliatins; Female; Fetal Membranes, Premature Rupture; Genotype; Humans; Infant, Newborn; Infectious Disease Transmission, Vertical; Nose; Pharynx; Pregnancy; Serotyping; Staphylococcal Scalded Skin Syndrome; Staphylococcus aureus; Umbilical Cord; Vagina

Haemophilus influenzae type b, a causative agent of bacterial sepsis and meningitis in young children, contains a single superoxide dismutase (SOD), a cytoplasmic MnSOD. To study the role of this enzyme, a chromosomal sodA::lacZ mutant (M-2) was constructed. M-2 had an increased sensitivity towards oxygen and the redox-active agent paraquat. A 3.4-fold increase in sodA-lacZ expression was found in M-2 grown with oxygen supply rates between 3 and 36 mmol of O2/liter/h. In similar experiments with the wild type, assaying SodA activity, a 3.1-fold increase was found. Both the wild type and M-2 grew best at the lowest oxygen supply rate tested, consistent with the notion that H. influenzae prefers a more anaerobic environment. In the infant rat model of infection, the ability of M-2 to colonize the nasopharynx was found to be impaired, but its ability to cause invasive disease was unaffected. This suggests that after invasion, the growth disadvantage imposed by a SodA- phenotype is not limiting.

Topics: Animals; Bacteremia; Haemophilus Infections; Haemophilus influenzae; Mutation; Nose; Oxidative Stress; Pharynx; Rats; Superoxide Dismutase; Virulence

Infectious complications associated with electroconvulsive therapy (ECT) are extremely unusual. When five of nine patients undergoing ECT at one facility on June 20, 1996 developed Staphylococcus aureus bloodstream infection (BSI), an investigation was initiated. A retrospective cohort study, a procedure review, and observational and microbiologic studies were performed. A case was defined as any patient who had ECT at Facility A from June 1, 1995 through June 20, 1996 and developed S. aureus BSI <30 days after ECT. The post-ECT S. aureus BSI rate was significantly greater on the epidemic day than the pre-epidemic period, (i.e., June 1, 1995 through June 19, 1996) (5 of 9 vs 0 of 54 patients, P < 0.001). All patients during the study period received propofol before ECT. Case patients were more likely than noncase patients to have higher maximum temperature after ECT (median 103.9 degrees F vs 100.0 degrees F, P < 0.03) and a greater time from preparation of intravenous medications to infusion (median 2.1 vs 1.1 h, P = 0.01). All case-patient S. aureus isolates were indistinguishable by pulsed field gel electrophoresis. Our investigation suggests that the ECT-associated S. aureus BSIs were associated with infection control breaks, which possibly led to the extrinsic contamination of propofol. Prevention of propofol-associated infectious complications requires aseptic preparation and use immediately before infusion.

Topics: Aged; Aged, 80 and over; Anesthetics, Intravenous; Bacteremia; Cohort Studies; Drug Contamination; Electroconvulsive Therapy; Electrophoresis, Gel, Pulsed-Field; Female; Fever; Hand; Humans; Infection Control; Male; Middle Aged; Nose; Peer Review, Health Care; Propofol; Retrospective Studies; Staphylococcal Infections; Staphylococcus aureus; Time Factors

In vitro collagen binding of 216 Staphylococcus aureus isolates from patients with various diagnoses was studied. Polymerase chain reaction was used to examine these isolates regarding the existence of the corresponding cna gene. Distribution of capsular polysaccharide (CP) types was examined. Fifty-six (57%) of 99 S. aureus isolates from patients with endocarditis or bacteremic bone or joint infection were cna-positive compared with 65 (56%) of 117 isolates from bacteremic patients without signs of bone or joint infection (P = .99). There was a good correlation between in vitro collagen binding and presence of the cna gene. These data suggest that collagen binding is not a prerequisite for the development of endocarditis, osteomyelitis, or septic arthritis. There was no significant difference in the distribution of CP types among various patient groups, although there was a strong association between CP type 8 and the existence of the cna gene.

Topics: Antibodies, Bacterial; Antigens, Bacterial; Bacteremia; Bone Diseases, Infectious; Carrier Proteins; Carrier State; Collagen; Endocarditis, Bacterial; Gene Expression; Genes, Bacterial; Humans; Joint Diseases; Nose; Polymerase Chain Reaction; Polysaccharides, Bacterial; Staphylococcal Infections; Staphylococcus aureus; Wound Infection

To determine the relevance of nasal carriage of Staphylococcus aureus, either methicillin-sensitive (MSSA) or methicillin-resistant (MRSA), as a risk factor for the development of nosocomial S aureus bacteremia during an MRSA outbreak.. In this prospective cohort study, 488 patients admitted to an intensive care unit (ICU) during a 1-year period were screened with nasal swabs within 48 hours of admission and weekly thereafter in order to identify nasal S aureus carriage. Nasal staphylococcal carriers were observed until development of S aureus bacteremia, ICU discharge, or death.. One hundred forty-seven (30.1%) of 488 patients were nasal S aureus carriers; 84 patients (17.2%) harbored methicillin-sensitive S aureus; and 63 patients (12.9%) methicillin-resistant S aureus. Nosocomial S aureus bacteremia was diagnosed in 38 (7.7%) of 488 patients. Rates of bacteremia were 24 (38%) of the MRSA carriers, eight (9.5%) of the MSSA carriers, and six (1.7%) of noncarriers. After adjusting for other predictors of bacteremia by means of a Cox proportional hazard regression model, the relative risk for S aureus bacteremia was 3.9 (95% confidence interval, 1.6-9.8; P = 0.002) for MRSA carriers compared with MSSA carriers.. Among ICU patients, nasal carriers of S aureus are at higher risk for S aureus bacteremia than are noncarriers; in the setting of an MRSA outbreak, colonization by methicillin-resistant strains represents a greater risk than does colonization by MSSA and strongly predicts the occurrence of MRSA bacteremia.

Topics: Adult; Aged; Bacteremia; Carrier State; Cohort Studies; Confidence Intervals; Cross Infection; Female; Humans; Intensive Care Units; Male; Methicillin; Methicillin Resistance; Middle Aged; Nose; Proportional Hazards Models; Prospective Studies; Risk Factors; Staphylococcal Infections; Staphylococcus aureus

A cluster of six pediatric cases of deep-seated Staphylococcus aureus infection after heart operations prompted us to perform molecular typing of the S. aureus isolates by pulsed-field gel electrophoresis. This revealed the presence of genotypically distinct isolates in four of the six patients. Isolates of two patients were genotypically identical. All patients carried S. aureus in the anterior nares. In each patient, the banding pattern of deoxyribonucleic acid in these isolates was indistinguishable from that in strains isolated from blood or wound cultures. Molecular typing with pulsed-field gel electrophoresis ruled out nosocomial transmission of S. aureus between four patients; at the same time, it provided evidence for an association between nasal colonization and postoperative wound infection. Epidemiologic investigation of potential links between two patients with identical isolates did not provide any evidence for nosocomial transmission of S. aureus between these patients. Because nasal colonization with S. aureus may be a risk factor for surgical wound infection in pediatric patients undergoing heart operations, preoperative decolonization appears to be warranted.

Topics: Anti-Bacterial Agents; Bacteremia; Bacterial Typing Techniques; Child; Child, Preschool; Cross Infection; DNA Probes; DNA, Bacterial; Electrophoresis, Gel, Pulsed-Field; Female; Genotype; Heart Defects, Congenital; Humans; Infant; Male; Nose; Preoperative Care; Risk Factors; Staphylococcal Infections; Staphylococcus aureus; Sternum; Surgical Wound Infection

Surveillance of 101 hemodialysis patients for Staphylococcus aureus positive nasal cultures was performed by monthly nasal swabs over a 27-month period. All positive cultures were treated with a prophylactic antibiotic regimen. Forty-seven (46.5%) patients had one or more positive cultures. The surveillance period was longer in the S. aureus nasal carriers (p = 0.004). The frequency of positive cultures correlated with the duration of surveillance (p = 0.029). The incidence of S. aureus bacteremia was greater in patients with two or more positive cultures (p = 0.030). This study suggests that continuous surveillance for S. aureus nasal colonization is essential to properly identify all patients at risk of developing S. aureus bacteremias.

Topics: Anti-Bacterial Agents; Bacteremia; Cohort Studies; Drug Therapy, Combination; Female; Hemodialysis Units, Hospital; Humans; Incidence; Kidney Failure, Chronic; Male; Middle Aged; Nose; Retrospective Studies; Risk Factors; Staphylococcal Infections; Staphylococcus aureus; Time Factors

A single point study was conducted to determine which surface sites best represent the density and composition of the coagulase-negative staphylococcal (CNS) colonizing flora in premature neonates. Five different surface sites of six randomly selected neonates hospitalized in a neonatal intensive care unit (NICU) for a month were examined. The individual strains and their clonal organization within CNS species were identified using restriction endonuclease fingerprinting of whole chromosomal DNA and ribosomal RNA genes. Cultures of the scalp, umbilicus, foot, nose and rectum were collected and quantitatively processed. Ten colonies were typed per surface culture. The most dense CNS colonization was noted on the umbilicus (mean 1.2 x 10(4) c.f.u. cm-2), foot (mean 1.6 x 10(3) c.f.u. cm-2) and nose (mean 1.7 x 10(3) c.f.u. cm-2) of NICU neonates. Scalp and rectum were scarcely colonized. Of all the CNS surface isolates, S. epidermidis accounted for 77.7% (219/282) and S. haemolyticus, S. warneri and S. capitis accounted for 20.6% (58/282), 1.4% (4/282) and 0.4% (1/282), respectively. Colonization of each surface site comprised a maximum of five different strains representing four CNS species. Overall, five clones of S. epidermidis, two of S. haemolyticus, one of S. warneri and one of S. capitis were noted among the 282 isolates. The most predominant were two clones of S. epidermidis and one of S. haemolyticus; they accounted for 94% (265/282). Cultures from the foot and scalp represented the most heterogeneous CNS colonization of the five sites examined.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Bacteremia; Coagulase; Cross Infection; DNA Fingerprinting; DNA, Bacterial; Drug Resistance, Microbial; Foot; Humans; Infant, Newborn; Infant, Premature; Intensive Care Units, Neonatal; Mucous Membrane; Nose; Rectum; Scalp; Skin; Staphylococcal Infections; Staphylococcus; Umbilicus

The incidence of S. aureus bacteraemia in a haemodialysis unit was studied over 2 years (167.75 patient-years of follow-up) during which nasal calcium mupirocin was used to eradicate nasal S. aureus carriage; this incidence was compared to that previously observed in the same unit before the use of nasal mupirocin (185.8 patient-years). Nasal mupirocin led to eradication of nasal S. aureus carriage in 96.3% of surveillance cultures and to a fourfold reduction in the incidence of S. aureus bacteraemia per patient-year, from 0.097 before mupirocin to 0.024 with mupirocin use (P = 0.008). Once or thrice weekly maintenance regimens of mupirocin were equally efficacious. The incidence of bacteraemia caused by other micro-organisms was not significantly affected. One single mupirocin-resistant isolate was identified in a nasal surveillance culture. Eradication of S. aureus from the nares did not lead to overgrowth by other micro-organisms. Chemoprophylaxis with nasal mupirocin in haemodialysis patients is cost-effective.

Topics: Administration, Intranasal; Adult; Aged; Bacteremia; Carrier State; Cost-Benefit Analysis; Humans; Middle Aged; Mupirocin; Nose; Ointments; Renal Dialysis; Staphylococcal Infections; Staphylococcus aureus