UPPER-LOBE PREDOMINANT NITROFURANTOIN-INDUCED PULMONARY INJURY: A CASE REPORT

SESSION TITLE: Imaging SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 pm - 02:15 pm INTRODUCTION: Nitrofurantoin is an antibacterial agent frequently used in treatment and prophylaxis of patients with recurrent urinary tract infections (UTI’s). Pulmonary toxicity due to nitrofurantoin has two main presentations: an acute onset after a short course of therapy and a chronic onset developing after several months or years of nitrofurantoin therapy. The most often reported computed tomography (CT) chest finding of nitrofurantoin-induced lung disease is bilateral areas of ground-glass attenuation with no dominant pattern of zonal distribution. Upper-lobe predominant pattern has been seldom reported. CASE PRESENTATION: A 79-yr-old female with past history of recurrent UTI’s in the past 12 months; treated with multiple courses of antibiotics including nitrofurantoin, presented with complaints of progressively worsening dyspnea on exertion associated with a dry cough for 3-4 months. In ED, the patient was tachycardic, tachypneic and hypoxic with SpO2 of 80% on ambient air. Physical examination revealed few scattered rhonchi bilaterally. She was noted to have leukocytosis and elevated serum globulin levels. Pro-B-type natriuretic peptide and procalcitonin levels were within normal range. Chest x-ray showed prominent upper lobe coarse lung markings. CT chest showed lobular upper lobe ground glass infiltrates with interlobular septal thickening. Echocardiogram showed mild concentric left ventricular hypertrophy with normal systolic function. Following exclusion of infection and heart failure; chronic nitrofurantoin-induced lung disease was diagnosed. Nitrofurantoin was discontinued and the patient was treated with oral glucocorticoids. Patient’s symptoms improved and she was discharged on a tapering dose of steroids. Upon outpatient follow-up at 6 weeks; patient reported significantly improved dyspnea on exertion and CT chest showed interval resolution of upper lobe ground-glass opacities and septal thickening. DISCUSSION: Nitrofurantoin-induced pulmonary injury is an underdiagnosed cause of chronic dyspnea and discontinuation of nitrofurantoin is the cornerstone of therapy. Regression of symptoms and radiographic abnormalities may take weeks to months following discontinuation. Oral glucocorticoids may expedite recovery and benefit patients with severe respiratory impairment. The principal chronic alterations associated with nitrofurantoin are usually found in the lung bases. In the case in question, the findings were predominantly in the upper lobes. The favorable clinical evolution after discontinuation of nitrofurantoin, resolution of CT chest findings and the absence of recurrence after discontinuation of glucocorticoids established a causal relationship. CONCLUSIONS: Patients on long-term nitrofurantoin therapy should be regularly monitored for pulmonary adverse effects. Clinicians should be cognizant of the varied clinical and radiographic patterns of nitrofurantoin-induced lung disease. Reference #1: https://www.ncbi.nlm.nih.gov/pubmed/18392467/ DISCLOSURES: No relevant relationships by Asif Abdul Hameed, source=Web Response No relevant relationships by Adeeba Afrah, source=Web Response Speaker/Speaker's Bureau relationship with Sunovion Please note: $1001 - $5000 Added 02/28/2018 by Michael Korman, source=Web Response, value=Honoraria