Pneumonia eosinofílica crônica secundária ao uso prolongado de nitrofurantoína: achados da tomografia computadorizada de alta resolução do tórax

Abstract

The authors report the case of a female patient who developed chronic eosinophilic pneumonia secondary to long-term use of nitrofurantoin for prophylaxis of recurrent urinary tract infections due to urethral stenosis. On high-resolution computed tomography scans, the pulmonary reaction to nitrofurantoin most commonly manifests as an interstitial-alveolar pattern in both lung bases. However, in this case, the alterations were most pronounced in the periphery of the upper lobes. In itself, this tomographic profile is strongly indicative of chronic eosinophilic pneumonia. The patient had previously been submitted to an open lung biopsy. The diagnosis of chronic eosinophilic pneumonia was confirmed through a review of the biopsy.Keywords: Pneumonia; Pulmonary eosinophilia; Nitrofurantoin/adverse effects; Tomography, X-ray computed. ResumoOs autores relatam o caso de uma paciente com estenose de uretra que desenvolveu pneumonia eosinofílica crônica secundária ao uso prolongado de nitrofurantoína como profilaxia para infecção urinária de repetição. A paciente havia sido submetida a uma biópsia pulmonar a céu aberto. É dada ênfase aos achados da tomografia computadorizada de alta resolução do tórax, já que, embora as alterações pulmonares associadas à toxicidade da nitrofurantoína geralmente sejam basais e bilaterais, no caso aqui descrito, as lesões de natureza interstício-alveolares situaram-se nas regiões subpleurais dos lobos superiores. Esses achados, por si só, são muito sugestivos de pneumonia eosinofílica crônica. O diagnóstico foi confirmado por meio da revisão da biópsia.

Nitrofurantoin-induced lung disease and prophylaxis of urinary tract infections

“…1,6,9 It is thought to be due to direct toxicity, which, unlike acute hypersensitivity reactions, is dose-related. 2,11 It is most commonly seen in older women, likely due to their higher prevalence of UTIs, with a median age of 60 to 70 years. 2,3 It usually presents with an insidious onset of cough and progressive dyspnoea, although chest pain, myalgia, weight loss and fatigue may also occur.…”

“…2,3 It usually presents with an insidious onset of cough and progressive dyspnoea, although chest pain, myalgia, weight loss and fatigue may also occur. 11,12 Given the insidious onset, symptoms can be mistaken for more common causes such as heart failure. Examination findings include inspiratory crepitations and possibly clubbing.…”

“…12 PFT may reveal a restrictive pattern with reduced diffusion capacity. 11 HRCT scan findings are varied and include ground-glass attenuation, honeycombing, inter-and intralobular septal thickening, traction bronchiectasis and organising pneumonia. [11][12][13] There are many different forms of pulmonary involvement in NILD (see Table 1).…”

“…Resolution of chronic PRIMARY CARE RESPIRATORY JOURNAL www.thepcrj.org Table 1. Pulmonary manifestations of nitrofurantoininduced lung disease [11][12][13][14][15][16] NILD can take from several months to a year. 5,12 Prognosis depends on early recognition and cessation of the drug.…”

“…Patients should have 6-monthly CXR and monitoring of liver function to allow early detection of complications. 11,21 It may be advisable to avoid long-term nitrofurantoin in those with chronic pulmonary conditions given that they are likely to have poor respiratory reserve to begin with. In such cases, trimethoprim may be used as first line.…”