Reduced susceptibility to azithromycin and high percentages of penicillin and tetracycline resistance in Neisseria gonorrhoeae isolates from Manaus, Brazil, 1998.

BACKGROUND: The identification of Neisseria gonorrhoeae isolates resistant to antimicrobial agents currently recommended for the treatment of gonococcal infections continues to escalate globally. Thus, in some areas, resistance to fluoroquinolone drugs is commonplace; several reports document resistance to third-generation cephalosporins, and the sporadic isolation of spectinomycin-resistant isolates continues unabated. Gonococcal resistance to azithromycin, an antibiotic used for the primary treatment of gonococcal infections in some Latin American countries, also has been described. Because the prevalence of resistant isolates is insufficiently documented in many areas of Latin America, the efficacy of locally recommended therapies for gonococcal infections is often unknown. GOAL: To determine the antimicrobial susceptibility and strain types of N gonorrhoeae isolates collected in Manaus, Brazil. These data will establish antimicrobial susceptibility baseline data for the region as a reference point for future surveillance. STUDY DESIGN: Consecutive N gonorrhoeae isolates from urethral and endocervical specimens were collected and examined for identity, antimicrobial susceptibility, and strain type (plasmid content, tetM type, auxotype, and serovar). RESULTS: Most of the isolates (65/81; 85.2%) were resistant to tetracycline, penicillin, or both, with the majority (n = 62) carrying plasmid-mediated resistance to tetracycline (tetracycline-resistant N gonorrhoeae [TRNG]). All of the TRNG contained the Dutch-type tetM plasmid, and 18 were A/S class NR/IA-02. Penicillinase-producing N gonorrhoeae comprised 8.2% (7/81) of the isolates. Of these seven isolates, four also were TRNG, and two carried chromosomal resistance to tetracycline. The isolates were susceptible to ciprofloxacin, spectinomycin, and ceftriaxone. However, 23 isolates were characterized by reduced susceptibility to azithromycin (MIC, 0.25-0.5 microg/ml), and one isolate had reduced susceptibility to ciprofloxacin (MIC, 0.25 microg/ml). CONCLUSIONS: This study supports the continued use of third-generation cephalosporins, spectinomycin, and fluoroquinolone drugs for the primary treatment of gonococcal infections in Manaus. The occurrence of isolates with reduced susceptibility to azithromycin and ciprofloxacin underscores the importance of ongoing antimicrobial susceptibility monitoring to support decisions regarding appropriate drugs for the treatment of gonococcal infections.

Validation of national algorithms for the diagnosis of sexually transmitted diseases in Brazil: results from a multicentre study.

OBJECTIVE: To validate STD flow charts for the management of genital discharge and genital ulcer currently recommended by the National STD Control Programme in Brazil. METHODS: A study was conducted in five Brazilian STD clinics from January to June 1995. After an interview, a clinical examination was performed by a physician, who recorded a presumptive diagnosis, based on his/her clinical experience. This diagnosis was compared with a gold standard laboratory diagnosis in order to calculate sensitivity, specificity, and positive predictive value of the clinical diagnosis. The validity of the simulated national flow charts was assessed using the same method. RESULTS: A total of 607 men and 348 women participated in the study. Gonorrhoea was the aetiology most frequently detected in men with urethral discharge. The sensitivity of the clinical diagnosis was far lower than the sensitivity fo the national flow chart, using the syndromic approach, for both gonococcal and chlamydial urethritis. Adding a simple laboratory test (Gram stain) to the national flow chart increased the specificity and positive predictive value for gonorrhoea. Among the women with vaginal discharge, a cervical infection was detected in 17%, a vaginal infection in 74%, and mixed infection in 9%. The sensitivity of the diagnosis for cervical infection increased from 16% (clinical aetiological approach) to 54% (when adding a syndromic approach) and to 68% when adding a risk assessment, as in the national flow charts. The cure or improved rate of genital ulcers was 96% after 1 week. CONCLUSIONS: The results of the study will help to convince policy makers and those involved in training healthcare workers in Brazil of the public health advantages of the syndromic approach, as an essential part of STD/HIV control activities.