An imported enteric fever caused by a quinolone-resistant Salmonella typhi

Recent reports indicate that nalidixic acid susceptibility correlates well with the clinical outcome of patients with Salmonella Typhi infection treated with quinolones. We report a case of enteric fever caused by S Typhi in which the isolate was resistant to nalidixic acid, but showed in vitro susceptibility to ciprofloxacin. Following treatment with ciprofloxacin, the clinical outcome was not satisfactory and the patient had a relapse. However, after using a higher dose of ciprofloxacin, the patient was cured. We recommend that all Salmonella systemic infections resistant to nalidixic acid with in vitro but decreased susceptibility to fluoroquinolones be treated with other antibiotics like third-generation cephalosporins or azithromycin. These patients should be closely followed up and observed for further relapse.