DIGGING DEEPER: WHEN AN HRCT IS NOT ENOUGH FOR AN ILD DIAGNOSIS

Abstract

SESSION TITLE: Monday Fellow Case Report Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/21/2019 02:30 PM - 03:15 PM INTRODUCTION: 69-year old Native American male, never-smoker, presents with 3-month history of shortness of breath. His symptoms persisted despite courses of steroids and antibiotics. He underwent a bronchoscopy at the referring hospital with inconclusive results and was subsequently transferred to our center on steroids for a working diagnosis of ILD. He has no smoking history, no pets, no recent travel, and no occupational exposures. He pursued a hobby mowing his farm in Oklahoma. CASE PRESENTATION: His admission computed tomography (CT) scan of the chest showed a mosaic pattern of hyperlucent lung, normal appearing parenchyma, and ground glass ("headcheese sign") on a background of traction bronchiectasis and reticulations. The findings were concerning for an acute on chronic process, and specifically subacute on chronic hypersensitivity pneumonitis given the constellation of findings. Based on the CT results, empiric prednisone 60mg/day was started. Lab workup for connective tissue disease and hypersensitivity pneumonitis was unremarkable. Given cardiac comorbidities, he was deemed not a surgical lung biopsy candidate, so a repeat bronchoscopy was pursued. TBBX specimens demonstrated macrophages with intracytoplasmic yeast forms with some budding and a hint of capsule formation. Mucicarmine stain showed mucicarmine positive forms consistent with infection by cryptococcus. Confirmatory cryptococcal serum antigen was positive, 1:160. The patient had no signs of being immunocompromised, and HIV status was negative. He was started on fluconazole and a lumbar puncture was performed looking for CNS involvement, which was negative. DISCUSSION: Cryptococcus is a fungal infection that usually affects immunocompromised hosts. It can be readily detected with high sensitivity and specificity in both serum and CSF studies. In immunocompetent patients, treatment consists of a prolonged course of fluconazole (6 to 12 months). CONCLUSIONS: Both infectious and noninfectious diseases of the lung can present radiographically and clinically similar. A comprehensive workup is important to achieve the correct diagnosis in a timely fashion. Reference #1: McMullan BJ, Halliday C, Sorrell TC, et al: Clinical utility of the cryptococcal antigen lateral flow assay in a diagnostic mycology laboray. PLoS One 7(11):e49541, 2012. Reference #2: Tanner DC, Weinstein MP, Fedorciw B, et al: Comparison of commercial kits for detection of cryptococcal antigen. J Clin Microbiol 32(7):1680–1684, 1994. DISCLOSURES: No relevant relationships by Alastair Moore, source=Web Response No relevant relationships by Haala Rokadia, source=Web Response No relevant relationships by Christopher Wood, source=Web Response