Nitrofurantoin-induced Toxicity. A Diagnostic Challenge.

Nitrofurantoin is an antimicrobial widely used in the treatment and prophylaxis of recurrent urinary tract infections. It carries a potential risk of pulmonary complications, that, while low (<1%), should be suspected in patients who develop respiratory symptoms during its administration, especially in subacute and chronic presentations. Given the non-specific clinical and radiological presentation, nitrofurantoin-induced pulmonary toxicity should be included in the differential diagnosis. We report the case of an 83-year-old female patient who, after several months of treatment with nitrofurantoin, developed progressive cough and dyspnea until she was finally admitted to our department for respiratory failure. Imaging studies revealed bilateral interstitial lung involvement. This case highlights the importance of maintaining a high index of suspicion to avoid, as far as possible, progression to more severe pulmonary forms.