Correlation between In vitro susceptibility and treatment outcome with azithromycin in gonorrhoea: a prospective study.

PURPOSE: This prospective study was carried out to determine the antimicrobial susceptibility of Neisseria gonorrhoeae isolates by disc diffusion method and minimum inhibitory concentration (MIC) by E -test with special reference to azithromycin. Also, the correlation between in vitro susceptibility and treatment outcome with single 2 g oral dose azithromycin was assessed. METHODS: The study included 75 gonococcal isolates from males with urethritis, females with endocervicitis and their sexual contacts. All isolates were subjected to susceptibility testing for penicillin, ciprofloxacin, tetracycline, ceftriaxone, spectinomycin, cefixime and azithromycin. Males with gonococcal urethritis were randomised to receive a single dose of either azithromycin or ceftriaxone. Forty-two men with urethritis received 2 g single oral dose azithromycin, while all other patients were given 250 mg parentral ceftriaxone. All patients were called for follow-up to assess clinical and microbiological cure rates. RESULTS: While all the isolates were susceptible to ceftriaxone, spectinomycin, cefixime and azithromycin; 74 (98.7%), 24 (32%) and 23 (30.7%) strains were resistant to ciprofloxacin, penicillin and tetracycline respectively, by both disc diffusion method and E -test. The MIC range, MIC50 and MIC90 of N. gonorrhoeae strains, to azithromycin were 0.016-0.25, 0.064 and 0.19 microg/mL, respectively. Follow-up attendance of the patients was 52.4 with 100% clinical and microbiological cure rates. CONCLUSIONS: Results of our study indicate that 2 g single oral dose azithromycin is safe and effective in the treatment of uncomplicated gonorrhoea.

Epidemilogical analysis of Neisseria gonorrhoeae isolates by antimicrobial susceptibility testing, auxotyping and serotyping.

PURPOSE: This study was carried out to analyze the epidemiology of gonorrhea based on antimicrobial susceptibility testing, auxotyping and serotyping in New Delhi, India. METHODS: Sixty gonococcal isolates from males with urethritis, females with endocervicitis and their sexual contacts were studied. The isolates were subjected to antimicrobial susceptibility testing, auxotyping and serotyping for epidemiological characterization. RESULTS: We observed nine antibiotic resistance patterns. Ninety-eight percent of isolates were resistant to ciprofloxacin, while 20% isolates were penicillinase producing N. gonorrhoeae (PPNG) and 18.3% isolates were tetracycline resistant N. gonorrhoeae (TRNG). Eight auxotypes were observed, of which the NR (non-requiring), proline requiring and arginine requiring were most common auxotypes. On the basis of serotyping alone, the gonococcal isolates could be differentiated into three serogroups and 18 serovars. Serogroup WI represented 46.7% and WII/III represented 51.7% of isolates and one strain was WI and WII/WIII serogroup combination. When results of auxotyping and serotyping were combined (A/S) 29 A/S classes could be identified. The most prevalent A/S classes were NR/Aost, NR/Arost, Pro/Aost and Pro/Boprt. CONCLUSIONS: Although A/S typing had the highest discriminatory index, isolates recovered from index case and their sexual contacts were found to be identical by all typing methods.

Simultaneous detection of Neisseria gonorrhoeae and Chlamydia trachomatis by PCR in genitourinary specimens from men and women attending an STD clinic.

Neisseria gonorrhoeae and Chlamydia trachomatis are the two most common bacterial sexually transmitted infections that manifest primarily as urethritis in males and endocervicitis in females, though the infection may be asymptomatic especially in women. Since complications may occur in untreated symptomatic and asymptomatic infected individuals, early diagnosis and treatment of infected individuals is required to prevent severe sequelae and spread of these diseases. Recently molecular amplification assays like Polymerase Chain Reaction (PCR) and Ligase Chain Reaction (LCR) have been found to be highly sensitive and specific methods for detection of N. gonorrhoeae and C. trachonmatis not only in urethral and cervical specimens but also in urine. The objective of this study was to screen male and female Sexually Transmitted Disease (STD) clinic attenders, with and without symptoms suggestive of urethritis and cervicitis for presence of N. gonorrhoeae and C. trachomatis using a multiplex PCR based assay, to compare its performance with culture for N. gonorrhoeae and Direct Fluorescent Antibody (DFA) staining for C. trachomatis and also to compare the efficacy of PCR test performed on urine and genital swab specimens collected from this high risk group. Genital specimens and urine was collected from STD clinic attenders. N. gonorrhoeae and C. trachomatis was detected in genital specimens by culture and DFA respectively. Multiplex PCR was used to detect N. gonorrhoeae and C. trachomatis infection in both genital and urine specimens. Among men with urethritis, N. gonorrhoeae was detected in 70% by culture and 77% by PCR, while C. trachomatis as detected in 7.5% by DFA and 17.5% by PCR. Among females with endocervicitis, N. gonorrhoeae was detected in 7.7% by culture and 30.7% by PCR, while C. trachomatis was detected in 7.7% by DFA and in 15.4% by PCR. None of the asymptomatic males were positive for N. gonorrhoeae and C. trachomatis by conventional methods, while 43.9% were positive for N. gonorrhoeae and 7.5% for C. trachomatis by PCR. Fifty per cent of asymptomatic women were positive for C. trachomatis by PCR alone. We encountered PCR positive but culture/DFA negative results and also PCR negative but culture/DFA positive results. In view of this a single PCR test cannot be used for diagnosis and treatment of N. gonorrhoeae and C. trachomatis infection unless confirmed by a second test.