agar and Pharyngitis

Topics: Agar; Artificial Intelligence; Automation, Laboratory; Bacteriological Techniques; Child; Chromogenic Compounds; Humans; Pharyngitis; Pharynx; Sensitivity and Specificity; Software; Streptococcal Infections; Streptococcus pyogenes

Tularemia which is a multisystem disease of humans and some animals, is endemic in North America, some parts of Europe and Asia. The causative agent, Francisella tularensis, is a fastidious gram-negative, intracellular bacterium which requires supplementation with sulphydryl compounds (cysteine, cystine, thiosulphate, isoVitaleX) for growth on common laboratory media. In this report, a case of oropharyngeal tularemia diagnosed by the isolation of the causative agent on non-selective-common microbiological agar, has been presented. The patient was from Yozgat located in central Anatolia where tularemia has not been reported so far. Forty-two years old male was admitted to the hospital with two weeks history of sudden onset fever, headache, generalized aches, sore throat, and cervical tender lump on the left. Physical examination revealed bilateral exudative tonsillitis and tender posterior cervical lymphadenopathy. He has been empirically treated with amoxicilin-clavulanic acid for 7 days with initial diagnosis of acute tonsillopharyngitis. However, he was admitted to the hospital since the symptoms persisted and swelling increased despite antibiotic therapy. Microscopical examination of the Gram and Ehrlich-Ziehl-Neelsen stained smears prepared from the surgically drained lymph node revealed PMNL, with no evidence of bacteria. Routine cultures of the lymph node material yielded growth of gram-negative coccobacilli only on human blood agar and the cultures were negative for pyogenic bacteria, acid-fast organisms and fungi. Pathologic examination of the drainage material revealed suppurative inflammation. Lymph node aspirate and serum samples of the patient together with the isolated strain were sent to reference laboratory for further investigation in accordance to the clinical and laboratory findings compatible with tularemia. The isolate was confirmed as F.tularensis by slide agglutination and direct immunofluorescence antibody tests, and identified as F.tularensis subsp. holarctica by polymerase chain reaction. Microagglutination test performed on patient's serum yielded positive with an antibody titer of 1/5120. Gentamicin (5 mg/kg/day) was initiated, and the therapy was completed for two weeks. The patient recovered completely without sequela. This case was presented in order to call attention to the strain of F.tularensis which failed to demonstrate a requirement for cysteine and enriched medium on primary isolation, but grew well on conventional lab

Topics: Adult; Agar; Agglutination Tests; Blood; Culture Media; Diagnosis, Differential; Fluorescent Antibody Technique, Direct; Francisella tularensis; Humans; Lymph Nodes; Male; Pharyngitis; Polymerase Chain Reaction; Tularemia

Within the last decade, Fusobacterium necrophorum subsp. funduliforme has been considered a clinically important pathogen causing pharyngitis especially in adolescents and young adults. F. necrophorum pharyngitis can progress into Lemierre's syndrome, which is a severe and life-threatening infection. However, throat swabs are not cultured anaerobically in the routine and even if cultured anaerobically, it can be difficult to identify F. necrophorum from the normal flora of the throat. F. necrophorum is therefore often overlooked as the cause of pharyngitis. In our laboratory, a F. necrophorum selective agar has been developed containing vancomycin and nalidixin, which inhibit the growth of most Gram-positive and many Gram-negative bacteria, respectively. β-haemolysis of horse blood can be detected, which further facilitates the detection and identification of F. necrophorum. The F. necrophorum selective agar was evaluated against a quantitative real-time polymerase chain reaction assay and shown to have a significantly higher sensitivity for detecting F. necrophorum than the anaerobic agar commonly used in Denmark. Furthermore, the F. necrophorum selective agar does not require experienced laboratory technicians, require fewer subcultures, is probably less expensive and is faster to perform than other culture methods.

Topics: Adolescent; Adult; Agar; Chi-Square Distribution; Child; Child, Preschool; DNA, Bacterial; Fusobacterium Infections; Fusobacterium necrophorum; Histocytochemistry; Humans; Infant; Microbial Sensitivity Tests; Microbiological Techniques; Middle Aged; Pharyngitis; Polymerase Chain Reaction; Sensitivity and Specificity; Young Adult

A new selective medium (CNA-P) that reduces or eliminates the inhibitory activity of bacteriocin-producing Streptococcus salivarius against beta-hemolytic streptococci has been developed and compared with sheep blood agar (SBA) for the sensitive detection of small numbers of beta-hemolytic streptococci in clinical specimens. CNA-P has as its basis a commercial medium (Difco Columbia CNA agar) supplemented with 5% (vol/vol) sheep blood, and the CNA is further modified by addition of 100 mM PIPES buffer [piperazine-N,N'-bis(2-ethanesulfonic acid)] (pH 7.5) to maintain cultures at an alkaline pH during incubation. CNA-P was shown to inhibit the production and/or release of four different types of S. salivarius bacteriocins or bacteriocin-like inhibitory molecules. The efficacies of CNA-P and SBA for detection of beta-hemolytic streptococci in 1,352 pharyngeal samples from 376 children were compared. The beta-hemolytic streptococcal isolates recovered from the samples included 314 group A (S. pyogenes), 61 group G, 33 group B, and 5 group C streptococci. Of 314 samples that yielded S. pyogenes, 300 were positive on CNA-P (96%) and 264 (86%) were positive on SBA. A significantly greater number of S. pyogenes isolates from these samples were recovered only on CNA-P (50 of 314) compared with the number of isolates recovered only on SBA (14 of 314). In addition, the degree of positivity, a measure of the total numbers of S. pyogenes isolates on the plate, was significantly higher on CNA-P than on SBA (2.40 versus 2.07; P < 0.001). Interestingly, CNA-P was also found to enhance the hemolytic activity of streptolysin O, allowing detection of streptolysin S-deficient S. pyogenes strains which might otherwise go undetected on SBA and other isolation media.

Topics: Agar; Antibiosis; Bacteriological Techniques; Blood; Buffers; Child; Child, Preschool; Culture Media; Humans; Hydrogen-Ion Concentration; Pharyngitis; Pharynx; Streptococcal Infections; Streptococcus; Streptococcus pyogenes; Tongue

Topics: Agar; Bacteriological Techniques; Blood; Child; Culture Media; Evaluation Studies as Topic; Humans; Pharyngitis; Pharynx; Sensitivity and Specificity; Sodium Chloride; Streptococcal Infections; Streptococcus; Streptococcus pyogenes

In a study on acute pharyngitis in general practice, we compared a selective group A streptococcal agar (ssA) for the recovery of group A beta-hemolytic streptococci (GABHS) with sheep blood agar. All plates were incubated at 36 degrees C in an atmosphere reinforced with 5% CO2 for 48 h with a first reading after 24 h. A total of 197 GABHS isolates were obtained from 721 throat cultures on both media. The recovery of GABHS was significantly higher after 48 h of incubation for both media. With the ssA plate, we detected significantly more GABHS after 24 h as well as after 48 h of incubation. The ssA plate reduced normal flora qualitatively and quantitatively. In conclusion, ssA is more sensitive and specific for the detection of GABHS than sheep blood agar and moreover easier to read. We recommend incubation for 48 h.

Topics: Agar; Bacteriological Techniques; Culture Media; Evaluation Studies as Topic; Humans; Pharyngitis; Streptococcal Infections; Streptococcus pyogenes

Topics: Agar; Child; Diagnostic Errors; Fluorescent Antibody Technique; Humans; Pharyngitis; Pharynx; Reagent Kits, Diagnostic; Streptococcal Infections; Streptococcus pyogenes; Time Factors

During recent years, it has become more and more common among general practitioners and pediatricians to inoculate and read agar plates for diagnosis of beta-hemolytic streptococci so that an accurate etiological diagnosis in cases of suspected tonsillitis can be made. As a control of the diagnostic quality, "unknown" streptococcal strains were distributed from the bacteriological laboratory to the practitioners performing this type of diagnostic procedure. The results show that the ability to correctly classify these strains varied greatly. Technical problems such as inadequate temperature control of relatively simple incubators were also found. Continuous education and information on beta-hemolytic streptococcal diagnostic procedures are important to ensure sufficient quality.

Topics: Agar; Bacteriological Techniques; Blood; Culture Media; Family Practice; Humans; Pediatrics; Pharyngitis; Streptococcal Infections; Streptococcus

Isolation of Haemophilus influenzae from specimens contaminated with upper respiratory tract microbial flora was attempted with three different media: enriched chocolate agar, chocolate agar plus vancomycin, and chocolate agar plus vancomycin, bacitracin, and clindamycin. Recovery rates of H. influenzae from 852 pediatric pharyngeal swab specimens were 6.0, 28.5, and 59.9%, respectively.

Topics: Adolescent; Agar; Child; Child, Preschool; Culture Media; Haemophilus Infections; Haemophilus influenzae; Humans; Infant; Pharyngitis; Pharynx; Respiratory Tract Infections

Five selective media for beta-haemolytic streptococci were tested and compared with the conventional blood agar plate using 200 throat swabs from children with possible streptococcal pharyngitis. The medium described by Liebermeister and Braveny, which is based on the reduction of nutrients and enhancement of the haemolytic activity of beta-streptococci, was markedly superior to the other selective media containing inhibiting agents.

Topics: Agar; Blood; Child; Culture Media; Humans; Pharyngitis; Pharynx; Streptococcus pyogenes

Fusobacterium egg yolk agar is a new medium selective for Fusobacterium species and differential for Fusobacterium necrophorum. The medium is a Brucella Agar base (Difco Laboratories, Detroit, Mich.) containing vancomycin, neomycin, josamycin, and egg yolk. All species of fusobacteria grew with only minimal inhibition. The mean log difference in counts between Fusobacterium egg yolk agar and control media for 30 strains of seven species of fusobacteria was 0.1922. F. necrophorum typically showed a strong lipase reaction. Most other organisms were significantly inhibited by the medium.

Topics: Agar; Egg Yolk; Female; Fusobacterium; Fusobacterium Infections; Fusobacterium necrophorum; Humans; Pharyngitis; Pharynx; Species Specificity

Sulfamethoxazole-trimethoprim blood agar (SXT-BA), neomycin blood agar (NEO-BA) and plain sheep blood agar plates (SBA) were compared for isolating group A streptococci in 1,954 throat cultures. SBA and SXT-BA had similar isolation rates (approximately 75% of all positive isolates). NEO-BA was significantly better (87% recovery). A combination of any two media gave 92-95% recovery of group A streptococci from throat specimens.

Topics: Adolescent; Agar; Animals; Child; Child, Preschool; Humans; Neomycin; Pharyngitis; Sheep; Streptococcal Infections; Streptococcus; Sulfamethoxazole

Topics: Agar; Bacteria; Bacteriological Techniques; Child; Humans; Neisseria; Pharyngitis; Pharynx; Prospective Studies; Streptococcus; Streptococcus pneumoniae

Viable counts of beta-haemolytic streptococci per ml. of saliva were made in the following groups: (1) children with acute streptococcal sore throat, (2) children with acute non-streptococcal sore throat, (3) children who had no sore throat but were streptococcal throat carriers, (4) children who neither had a sore throat nor were streptococcal throat carriers.The mean counts from cases of streptococcal sore throat and from streptococcal carriers were respectively 1.4 x 10(6) and 2.5 x 10(5) per ml.In a comparison of the efficiency of the throat swab, sublingual swab and specimen of saliva in isolating beta-haemolytic streptococci from the upper respiratory tract, culture of saliva produced the best results.

Topics: Agar; Bacteriological Techniques; Blood; Carrier State; Child; Gentian Violet; Humans; Pharyngitis; Saliva; Serotyping; Streptococcal Infections; Streptococcus; Streptococcus pyogenes

Topics: Agar; Animals; Bacteriology; Blood; Humans; Pharyngitis; Sheep; Streptococcus; Tonsillitis