Re: Diagnosis and management of recurrent urinary tract infections in non-pregnant women
We read with interest Gupta and Trautner’s review of the diagnosis and management of recurrent urinary tract infections (UTIs) in non-pregnant women, in which the use of prophylactic nitrofurantoin is suggested as one option.1 They correctly highlight the risk of pulmonary toxicity (commonly known as “Nitrofurantoin Lung”) associated with prolonged treatment and suggest this occurs following years of treatment. In Grampian we have identified 13 patients in the last 4 years with ”Nitrofurantoin lung”, 12 of whom were non pregnant women receiving treatment for prophylaxis of recurrent UTI. 83% of these women had received a course of Nitrofurantoin of ≤ 18 months duration pre-diagnosis, with a mean duration of treatment of 14 months. None had been aware of the potential for lung toxicity and the prescribing clinicians were surprised by the diagnosis. All patients were advised to stop taking Nitrofurantoin and 6 also received empirical oral steroid therapy. Serial spirometry was available in 9 patients noting dramatic improvement in lung function following cessation of Nitrofurantoin, (mean %predicted forced vital capacity of 78% at diagnosis, 110% following cessation) and serial chest radiographs also displayed improvement.
Data available from the Prescribing Information System for Scotland (PRISMS) records Nitrofurantoin prescription in the community setting has more than tripled from 2008 to 2012, from 3.4 to 11 prescribed items of Nitrofurantoin per 1000 patients. We believe this change in prescribing, advocated in current guidelines2,3, is reflected in our local experience and elsewhere in the UK 4,5. We therefore anticipate a continued increased in the incidence of “Nitrofurantoin lung” and are concerned that many clinicians have forgotten the potential for lung toxicity. Our own experience suggests it is initially misdiagnosed as cardiac failure, pneumonia and in once case as metastatic malignancy. We suggest patients are warned to report respiratory symptoms e.g. worsening cough, breathlessness if these develop while taking Nitrofurantoin and current guidelines and primary care prescribing systems place greater emphasis on the potential for toxicity, which is reversible if the association is recognised early enough.
1. Gupta K, Trautner BW. Diagnosis and management of recurrent urinary tract infections in non-pregnant women. BMJ 2013; 346
2. Gupta K, Hooton TM, Naber KG, Wullt B, Colgan R, Miller LG, et al. International clinical practice guidelines for the treatment of acute uncomplicated cystitis and pyelonephritis in women: A 2010 update by the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases. Clin Infect Dis2011;52:e103-20
3. Management of infection guidance for primary care for consultation and local adaptation. (2012). Retrieved May 20, 2013, from http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1279888711402
4. Madani Y, Mann B. Nitrofurantoin-induced lung disease and prophylaxis of urinary tract infections. Prim Care Respir J 2012; 21:337-41
5. Weir M, Daly GJ. Lung toxicity and Nitrofurantoin: the tip of the iceberg? QJM 2013; 106:271-2
Competing interests: No competing interests