agar and Gonorrhea

Culture of Neisseria gonorrhoeae is essential for surveillance of complete antimicrobial susceptibility profiles. In 2014, the culture success rate of N. gonorrhoeae from samples taken at the clinic for sexually transmitted infections (STI clinic), Oslo University Hospital, Norway, was only 20%. The present study aimed to improve gonococcal culture rates using bedside inoculation of patient samples on gonococcal agar plates and incubation at the STI clinic.. This prospective quality improvement study was conducted by the STI clinic and the Department of Microbiology at Oslo University Hospital from May 2016 - October 2017. When culture of N. gonorrhoeae was clinically indicated, we introduced a parallel 'bedside culture' at the STI clinic and compared results with the standard culture at the microbiology department. Samples were taken from urethra, anorectum, pharynx and cervix. Culture rates were compared across symptomatic and asymptomatic anatomical sites.. From 596 gonococcal-positive PCR samples, bedside culture had a significantly higher success rate of 57% compared to 41% with standard culture (p < 0.05). Overall, culture rate from symptomatic sites was 91% v. 45% from asymptomatic sites. The culture rates from different anatomical sites were as follows: urethra 93%, anorectum 64%, pharynx 28% and cervix 70%. Bedside culture significantly (p < 0.05) improved the culture rates for symptomatic urethral and asymptomatic pharyngeal samples.. Where feasible, bedside inoculation on gonococcal agar plates and incubation of samples from patients with gonorrhoea is recommended. This will improve the culture diagnostics and provide additional gonococcal isolates for antimicrobial resistance surveillance.

Topics: Agar; Anti-Bacterial Agents; Anti-Infective Agents; Drug Resistance, Bacterial; Female; Gonorrhea; Humans; Microbial Sensitivity Tests; Neisseria gonorrhoeae; Prospective Studies; Sexually Transmitted Diseases

Agar dilution is the gold standard method for phenotypic antimicrobial susceptibility testing (AST) for

Topics: Agar; Alberta; Anti-Bacterial Agents; Azithromycin; Cefixime; Ceftriaxone; Ciprofloxacin; Gonorrhea; Humans; Microbial Sensitivity Tests; Neisseria gonorrhoeae; Penicillins; Retrospective Studies; Tetracycline

Neisseria gonorrhoeae is a major concern of public health due to its extraordinary capacity to develop and acquire resistance to different antimicrobials used to treat gonorrhoea. Limited treatment options and uncontrolled transmission have raised the need to assess the antimicrobial susceptibility profile of the isolates and to establish affordable alternatives for laboratory diagnosis.. This study aimed to (i) determine the susceptibility profile of 336 clinical isolates of N. gonorrhoeae to ceftriaxone, azithromycin, ciprofloxacin, spectinomycin and gentamicin by the gold standard agar dilution method; (ii) assess the agreement among agar dilution and disc diffusion results for ciprofloxacin, azithromycin, ceftriaxone, spectinomycin and gentamicin.. All isolates were susceptible to ceftriaxone and spectinomycin. The levels of resistance to azithromycin and ciprofloxacin were 3.9% and 35.1%, respectively. Intermediate susceptibility to gentamicin was observed in 19.4% of isolates. There was 100% agreement between methods for spectinomycin and ceftriaxone, 99.7% for ciprofloxacin, and 85.7% for azithromycin. For gentamicin, there was 86.3% agreement between agar dilution and disc diffusion, resulting in intermediate susceptible by one method and susceptible by the other method, defined as minor errors. The discordance among agar dilution and disc diffusion results is acceptable for ciprofloxacin, ceftriaxone and spectinomycin as per CLSI M23-Ed4.. Spectinomycin and gentamicin can be considered in some cases as options for the treatment of gonorrhoea in Brazil. Disc diffusion can be an alternative method in routine testing with comparable accuracy to agar dilution.

Topics: Agar; Anti-Bacterial Agents; Azithromycin; Ceftriaxone; Ciprofloxacin; Gentamicins; Gonorrhea; Humans; Microbial Sensitivity Tests; Neisseria gonorrhoeae; Spectinomycin

We studied whether the Etest can be used as an alternative to agar dilution to determine antimicrobial susceptibilities of ceftriaxone, cefixime, and cefpodoxime in Neisseria gonorrhoeae surveillance. One hundred fifteen clinical and laboratory isolates of N. gonorrhoeae were tested following the Clinical Laboratory Improvement Amendments (CLIA)-approved CLSI standard agar dilution method and, separately, by the Etest according to the manufacturer's recommendations. The MICs were determined and compared. Ten laboratory-generated mutants were used to simulate substantially nonsusceptible specimens. The Etest and agar dilution methods were well correlated. Statistical tests produced regression R2 values of 88%, 82%, and 85% and Pearson correlation coefficients of 92%, 91%, and 92% for ceftriaxone, cefixime, and cefpodoxime, respectively. When paired comparisons were made, the two tests were 88.7%, 80%, and 87% within 1 log2 dilution from each other for ceftriaxone, cefixime, and cefpodoxime, respectively. The within-2-log2 agreements were 99.1%, 98.3%, and 94.8% for ceftriaxone, cefixime, and cefpodoxime, respectively. Notwithstanding the good correlations and the within-2-log2 general agreement, the Etest results produced slightly lower MICs than the agar dilution results. In conclusion, we found that the Etest can be effectively used as an alternative to agar dilution testing to determine the susceptibility of N. gonorrhoeae to ceftriaxone, cefixime, and cefpodoxime, although we recommend further research into extremely resistant isolates. For isolates within the typical range of clinical MICs, reexamination of the Etest interpretation of susceptible and nonsusceptible categories would likely allow for successful transition from agar dilution to the Etest.

Topics: Agar; Anti-Bacterial Agents; Disk Diffusion Antimicrobial Tests; Gonorrhea; Humans; Neisseria gonorrhoeae

Modified Thayer-Martin (MTM) medium containing goat blood (MTMGB) and sheep blood (MTMSB) was compared for culture of N. gonorrhoeae. Evaluation of 252 endocervical specimens and quantitative culture of 10 strains revealed no significant difference in isolation and growth. MTMGB can be a suitable and cost-effective alternative for MTMSB.

Topics: Agar; Animals; Bacteriological Techniques; Blood; Cervix Uteri; Culture Media; Female; Goats; Gonorrhea; Humans; Neisseria gonorrhoeae; Serotyping; Sex Work; Sheep; Specimen Handling

Two commercial swab transport systems, Copan Amies gel agar with and without charcoal (Copan Diagnostics, Corona, Calif.), were compared to direct inoculation onto modified Thayer-Martin medium for detection of Neisseria gonorrhoeae in 1,490 endocervical specimens obtained from women attending a sexually transmitted disease clinic. Copan swabs were held in the transport system for 24 h at room temperature prior to inoculation onto modified Thayer-Martin medium. All cultures were incubated at 35 degrees C in 5% CO(2), and bacteria were identified on the basis of Gram stain, oxidase, and biochemical reactions. Copan Amies gel agar transport system without charcoal detected 77 of 81 (95%) direct inoculation culture-positive specimens, and Copan Amies gel agar transport system with charcoal detected 53 of 56 (95%) directly inoculated culture-positive specimens. Copan Amies gel agar without charcoal inoculated after 6 h supported growth of 56 (98%) positive cultures out of only 55 directly inoculated culture-positive specimens. This study demonstrates that Copan swabs represent a reasonable alternative, providing convenience, low cost, and ease of use while still maintaining a satisfactory recovery rate of N. gonorrhoeae from clinical specimens, if specimens can be inoculated onto selective media within a relatively short time period not involving overnight shipment.

Topics: Adult; Agar; Bacteriological Techniques; Charcoal; Culture Media; Evaluation Studies as Topic; False Negative Reactions; Female; Gonorrhea; Humans; Neisseria gonorrhoeae; Sensitivity and Specificity; Vaginal Smears

The macrolide-azilide susceptibility testing (agar dilution, disk diffusion, Etest) criteria for 105 Neisseria gonorrhoeae strains were evaluated. In addition, the potencies of azithromycin, clarithromycin, and erythromycin were studied. The most active macrolide-azilide agent was azithromycin (MIC at which 90% of the isolates are inhibited [MIC90], 0.5 microgram/ml) compared with clarithromycin (MIC90, 1.5 to 2 micrograms/ml) and erythromycin (MIC90, 2 to 4 micrograms/ml). The Etest (AB Biodisk, Solna, Sweden) was observed to produce MIC results very similar to those of the reference agar dilution test (GC agar base), with 100% of the results within 1 log2 dilution step of the reference MICs. The disk diffusion test zone diameters for all three drugs correlated at an acceptable level (r = -0.81 to -0.92) with the reference agar dilution MICs. Interpretive criteria for susceptibility were proposed for azithromycin at a MIC of < or = 2 micrograms/ml and a disk diffusion test zone of > or = 25 mm. No category for resistance was proposed because of the paucity of strains for which MICs were > 2 micrograms/ml. These tentative criteria should be further validated by correlations with clinical trial data for gonococcal strains (as they emerge) that have azithromycin MICs above the proposed susceptible category range.

Topics: Agar; Anti-Bacterial Agents; Azithromycin; Clarithromycin; Erythromycin; Evaluation Studies as Topic; Gonorrhea; Humans; In Vitro Techniques; Microbial Sensitivity Tests; Neisseria gonorrhoeae

A collection of 150 Neisseria gonorrhoeae isolates from Africa, where various resistance mechanisms among N. gonorrhoeae isolates are common, was used to the compare E test (AB Biodisk, Solna, Sweden) with agar dilution susceptibility testing. MICs obtained by the E test agreed within 1 log2 concentration by the agar dilution method for 97.5, 97.3, 96.6, 94, and 84.7% of the tested isolates for penicillin, ciprofloxacin, chloramphenicol, tetracycline, and trimethoprim-sulfamethoxazole, respectively. No significant difference in susceptibility categorization was observed between either method. The E test is an attractive alternative to the agar dilution technique and is a more appropriate method for N. gonorrhoeae susceptibility testing in developing countries.

Topics: Africa; Agar; Chromosomes, Bacterial; Developing Countries; Drug Resistance, Microbial; Gonorrhea; Humans; Microbial Sensitivity Tests; Neisseria gonorrhoeae; Plasmids; Reagent Strips

Topics: Agar; Bacteria; Bacteriological Techniques; Caseins; Culture Media; Female; Gonorrhea; Humans; Male; Neisseria gonorrhoeae; Urogenital System; Yeast, Dried

To assess the practical significance of reported increases in the prevalence of vancomycin-susceptible strains of Neisseria gonorrhoeae on isolation of this organism, antibiotic-free chocolate agar (CA), modified Thayer-Martin medium (MTM), and a vancomycin-free selective medium (VFSM) were compared in a sexually transmitted disease clinic. Among 326 cervical gonococcal infections detected in a comparison of CA with MTM, 92.0% were detected on CA, compared with 98.2% on MTM (P less than 0.001). Similarly, among 306 cervical infections detected in a comparison of MTM and VFSM, 95.8% of infections were detected with VFSM, compared with 98.4% for MTM (P = 0.10). For 1,632 urethral infections in men, all three media were equivalent, with none detecting fewer than 98% of the infections. Compared with a single inoculation, dual inoculation of MTM increased the diagnostic yield by 1.5% for 206 urethral infections and 2.4% for 83 cervical infections. In our clinic population, MTM is superior to CA or VFSM for the diagnosis of genital gonococcal infections, especially in women. The increased yield that accrued from inoculation of both MTM and either of the other media was not sufficiently high to warrant routine use of this practice in our clinic.

Topics: Agar; Community Health Centers; Culture Media; Female; Gonorrhea; Humans; Male; Neisseria gonorrhoeae; Urethral Diseases; Uterine Cervical Diseases; Vancomycin

Topics: Agar; Caseins; Culture Media; Female; Gonorrhea; Humans; Male; Neisseria gonorrhoeae; Yeast, Dried

A "chocolate" agar medium (CA-NCV) containing nystatin, colistin and vancomycin, was compared with the MNYC medium which contain lincomycin, colistin, amphotericin and trimethoprim. A total of 277 clinical specimens were cultured for gonococci, and 120 of these showed positive cultures on either or both of the media. The MNYC medium detected 96.6 per cent of the total number of positive cultures and 92.5 per cent of the patients and the CA-NCV medium after 80 and 79 per cent, respectively. Nearly half the positive cultures were detected on the MNYC medium after 24 hours of incubation. It is concluded that the MNYC medium is superior to the CA-NCV medium in the diagnosis of gonorrhoea.

Topics: Agar; Anti-Bacterial Agents; Culture Media; Female; Gonorrhea; Humans; Male; Neisseria gonorrhoeae

We have determined that isolates of Neisseria gonorrhoeae from patients with disseminated gonococcal infection (DGI) are different from randomly collected isolates from patients with uncomplicated (local) disease. Our comparison was based on the six phenotypic properties of: sensitivity to penicillin (PenS), erythromycin, and streptomycin; resistance to the bactericidal effects of pooled human sera; requirements for arginine, hypoxanthine, and uracil (AHU-); and sensitivity to toxic agar. Although the marked association among these traits made analysis difficult, several factors independently related to virulence were defined. The DGI isolates were significnatly more PenS and resistant to serum, even when the other variables were held constant. An apparent correlation between AHU- auxotype and virulence was shown to be due to the PenS property of most AHU- isolates. Thus, certain mutations to antibiotic resistance as well as susceptibility to sera, may result in loss of virulence in the gonococcus, perhaps through alteration of cell envelope structure.

Topics: Agar; Blood Bactericidal Activity; Erythromycin; Gonorrhea; Humans; Neisseria gonorrhoeae; Penicillin Resistance; Penicillins; Phenotype; Streptomycin; Transformation, Genetic; Virulence

Imferon, an iron-dextran complex, enhances the growth of Neisseria gonorrhoeae and N. meningitidis. The use of Imferon as a replacement for ferric nitrate, in a defined supplement for GC agar significantly increased the average colony sizes of both gonococci and meningococci. In comparison with Thayer-Martin medium, Imferon agar increased the speed and rate of isolation of gonococci from clinical specimens.

Topics: Agar; Diagnosis, Differential; Female; Ferric Compounds; Gonorrhea; Humans; Iron-Dextran Complex; Male; Neisseria gonorrhoeae; Neisseria meningitidis; Nitrates

A survey of 120 isolations of Neisseria gonorrhoeae from male patients showed that 47 (39%) isolates were unable to produce visible colonies without a supply of exogenous carbon dioxide. Of 63 strains, 25 strains required CO2 for isolation but none exhibited a CO2 requirement beyond subculture 4. CO2-requiring strains deprived of CO2 appeared to lose their colony-forming ability exponentially in an environment otherwise conductive to growth. The CO2 requirement was found to be linked to the initiation of growth. An agar-to-agar replica-plating device was used to study the early stages of colonial growth. The CO2 requirement was also found to correlate with the various phases of the colony growth cycle, such that it was required during lag phase, not required during the phase of rapid growth, and returned as colonies aged. These results are discussed.

Topics: Agar; Carbon Dioxide; Gonorrhea; Humans; Male; Neisseria gonorrhoeae

Topics: Agar; Animals; Bacteriological Techniques; Caseins; Cattle; Cervix Uteri; Culture Media; Culture Techniques; Female; Gonorrhea; Humans; Male; Neisseria gonorrhoeae; Urethra; Yeast, Dried

A modified Thayer-Martin medium, containing 2.0% agar, 0.25% dextrose, and 5.0 mug of trimethoprim per ml was compared to Thayer-Martin medium for growth of stock cultures of Neisseria gonorrhoeae and for isolation of N. gonorrhoeae from clinical specimens. Stock cultures and male urethral cultures grew equally well on both media, but the modified Thayer-Martin medium detected 10% more female patients positive for gonococci. A description is given of the use of a citric acid-sodium bicarbonate tablet for generating carbon dioxide in a sealed plastic bag containing a culture plate. Equivalent results were obtained on duplicate plates of 336 cultures and specimens when this procedure was compared with the standard candle jar extinction method of incubation. The tablet and plastic bag system has the advantages of economy, ease of use, and safety.

Topics: Agar; Bacteriological Techniques; Bicarbonates; Carbon Dioxide; Chromatography, Gas; Citrates; Culture Media; Evaluation Studies as Topic; Female; Glucose; Gonorrhea; Humans; Male; Methods; Neisseria gonorrhoeae; Proteus; Sodium; Trimethoprim

Topics: Agar; Bacteriological Techniques; Culture Media; Female; Gonorrhea; Humans; Neisseria gonorrhoeae

Topics: Agar; Bacteriological Techniques; Cells, Cultured; Female; Gonorrhea; Humans; Neisseria gonorrhoeae; New Jersey; Oxidoreductases; Specimen Handling; Staining and Labeling; Temperature; Time Factors

Topics: Adolescent; Agar; Cervix Uteri; Coitus; Culture Media; Female; Gonorrhea; Humans; Neisseria gonorrhoeae; Vaginal Smears; Vaginitis

Topics: Agar; Amphotericin B; Animals; Bacteriological Techniques; Culture Media; Gonorrhea; Hemoglobins; Horses; Methods; Microbial Sensitivity Tests; Neisseria gonorrhoeae; New York City; Nystatin; Saccharomyces cerevisiae; Trimethoprim; Vancomycin

Although no consistent results can be demonstrated when freshly isolated strains of Neisseria gonorrhoeae are tested for bacteriocin activity on chocolate blood agar, such activity can be demonstrated on GC base medium (Difco), enriched with a defined supplement. At the present time, using six indicator strains, 75% of isolates of N. gonorrhoeae show characteristic patterns of inhibition. These observations are encouraging and suggest that ;gonocin' typing may be possible.

Topics: Agar; Bacteriocins; Culture Media; Gonorrhea; Humans; Methods; Neisseria gonorrhoeae

Topics: Agar; Bacteriological Techniques; Caseins; Clinical Laboratory Techniques; Culture Media; Female; Glycine max; Gonorrhea; Humans; Male; Neisseria gonorrhoeae

Topics: Agar; Animals; Bacteriological Techniques; Blood; Diagnosis, Differential; Female; Germany, East; Gonorrhea; Horses; Humans; Male; Neisseria gonorrhoeae; Sheep; Statistics as Topic

Topics: Adolescent; Agar; Bacteriological Techniques; Culture Media; Female; Fluorescent Antibody Technique; Gonorrhea; Humans; Infant, Newborn; Male; Microscopy; Neisseria gonorrhoeae

Topics: Agar; Bacteriological Techniques; Blood; Carbohydrate Metabolism; Cervix Uteri; Culture Media; Diagnosis, Differential; Family Practice; Female; Gonorrhea; Humans; Male; Methods; Neisseria gonorrhoeae; Oxidoreductases; Specimen Handling; Urethra

Topics: Agar; Colistin; Culture Media; Gonorrhea; Humans; Neisseria gonorrhoeae; Vancomycin

Topics: Agar; Cytodiagnosis; Female; Gonorrhea; Humans; Male; Penicillin G Procaine; Polymyxins; Rectal Diseases; Vaginal Smears

Topics: Agar; Cacao; Female; Gonorrhea; Humans