1/6. Infections with non-penicillinase-producing neisseria gonorrhoeae treated with cefuroxime: treatment failures.Two men who acquired acute gonococcal urethritis in The netherlands and who were treated with cefuroxime (1.5 g given intramuscularly) failed to respond to this therapy. Pre- and post-treatment isolates of neisseria gonorrhoeae from these patients had MICs of 0.5 and 1.0 microgram of cefuroxime/ml.- - - - - - - - - - ranking = 1keywords = treatment failure (Clic here for more details about this article) |
2/6. High-level quinolone resistance in neisseria gonorrhoeae: a report of two cases.BACKGROUND AND OBJECTIVES: fluoroquinolones are widely used oral agents for treating neisseria gonorrhoeae. Resistance to these agents is sporadic and usually at a low level. Two instances of high-dose ciprofloxacin regimens failing in the treatment of gonococcal infection, caused by strains with high-level quinolone resistance, are reported. STUDY DESIGN: This is a case report. CONCLUSION: High-level resistance to quinolone antibiotics resulting in treatment failure was observed in two distinct gonococcal isolates from patients infected in the philippines (ciprofloxacin; minimal inhibitory contribution = 16 mg/l). Continued monitoring of the quinolone sensitivity of neisseria gonorrhoeae is appropriate and prudent.- - - - - - - - - - ranking = 0.25keywords = treatment failure (Clic here for more details about this article) |
3/6. Fluoroquinolone resistance in neisseria gonorrhoeae--colorado and washington, 1995.The fluoroquinolones ciprofloxacin and ofloxacin are among the antimicrobial agents recommended by CDC for treating gonorrhea (1). In the united states, decreased susceptibility or resistance of strains of neisseria gonorrhoeae to the fluoroquinolones has been reported only sporadically, and treatment failure associated with in vitro resistance has not been described (2). However, the recent occurrence of resistant cases in Denver and Seattle suggests that clinically important resistance to the fluoroquinolones may be emerging. This report describes the findings of the investigations of these cases.- - - - - - - - - - ranking = 0.25keywords = treatment failure (Clic here for more details about this article) |
4/6. Fluoroquinolone treatment failure in gonorrhea. Emergence of a neisseria gonorrhoeae strain with enhanced resistance to fluoroquinolones.BACKGROUND AND OBJECTIVES: Although emergence of clinical isolates of neisseria gonorrhoeae with decreased susceptibilities to fluoroquinolones and treatment failures in gonorrhea have been reported, there have been no clinical reports that fluoroquinolone treatments actually select quinolone-resistant strains, nor have isolates that exhibited clinically significant resistance been analyzed for resistance mechanisms. goals: To report a case of fluoroquinolone treatment failure in gonorrhea and emergence of a posttreatment isolate with enhanced resistance to fluoroquinolones; and to study mechanisms of quinolone resistance in the isolates from this patient. STUDY DESIGN: A patient with gonococcal urethritis treated with ofloxacin, 200 mg, three times daily for 5 days is described. Pretreatment and posttreatment isolates were tested for minimum inhibitory concentrations (MICs) of antimicrobial agents and analyzed for alterations in dna gyrase and topoisomerase IV. They were also examined for ofloxacin uptake. RESULTS: treatment failure with multiple doses of ofloxacin was observed in this case of gonorrhea. The pretreatment isolate showed decreased susceptibilities to fluoroquinolones (MIC of ofloxacin, 1.0 mg/l; MIC of ciprofloxacin, 0.25 mg/l), and had amino acid changes of Ser-91-->Phe in GyrA and Ser-87-->Ile in ParC. The posttreatment isolate exhibited an increase in resistance to fluoroquinolones (MIC of ofloxacin, 8.0 mg/l; MIC of ciprofloxacin, 1.0 mg/l). This isolate had identical alterations in GyrA and ParC, but exhibited significantly reduced uptake of ofloxacin. This isolate also showed a small decrease in susceptibilities to cephalosporins. CONCLUSIONS: Alterations in dna gyrase and topoisomerase IV confer clinically significant resistance to fluoroquinolones in N. gonorrhoeae strains. Treatment with multiple doses of fluoroquinolones is likely to bring about selection of more fluoroquinolone-resistant strains of N. gonorrhoeae and to influence susceptibilities to cephalosporins.- - - - - - - - - - ranking = 1.5keywords = treatment failure (Clic here for more details about this article) |
5/6. Fluoroquinolone-resistant neisseria gonorrhoeae--San Diego, california, 1997.The fluoroquinolones ciprofloxacin and ofloxacin are among the antimicrobials recommended for treating uncomplicated gonorrhea. Fluoroquinolone-resistant strains of neisseria gonorrhoeae have been identified frequently during the 1990s in the far east. In the united states, fluoroquinolone-resistant N. gonorrhoeae has been reported sporadically; resistance associated with clinical treatment failure has been reported previously in only one person, who probably acquired the infection in the philippines. This report describes the results of an investigation in 1997 of two cases of gonococcal infection in the united states with strains with a higher level of fluoroquinolone resistance than reported previously; clinical treatment failure occurred in one case.- - - - - - - - - - ranking = 0.5keywords = treatment failure (Clic here for more details about this article) |
6/6. Failure of azithromycin therapy in gonorrhea and discorrelation with laboratory test parameters.BACKGROUND: azithromycin is efficacious in the treatment of chlamydial genital tract infection but less so in gonorrhea. However, MICs of azithromycin for gonococci from previously reported azithromycin treatment failures were consistently below the 'susceptible' MIC level of 2 mg/L. GOAL OF THIS STUDY: To examine gonococci not eliminated with 1 g azithromycin therapy to establish treatment outcome/MIC correlates in gonorrhea. STUDY DESIGN: The MICs and phenotypes of gonococci isolated from five cases of treatment failure after 1 g azithromycin therapy were determined and compared with the MICs of a systematic sample of routine isolates. RESULTS: azithromycin MICs of gonococci from five cases of failed 1 g azithromycin treatment were 0.125 or 0.25 mg/L, well within the current 'susceptible' MIC range. None of the isolates were of the mtr phenotype. The MIC90 of a systematic sample of 219 gonococcal isolates was 0.25 mg/L. CONCLUSION: The antibiotic MIC/treatment outcome correlates that are usually found in gonorrhea do not apply for azithromycin. Current MIC criteria do not accurately define susceptibility or resistance of gonococci to azithromycin and by themselves do not predict the likely outcome of therapy. Pharmacokinetic factors may decrease the predictive value of MIC data.- - - - - - - - - - ranking = 0.5keywords = treatment failure (Clic here for more details about this article) |