COCCIDIOMYCOSIS MASQUERADING AS PULMONARY HISTIOCYTOSIS X

Abstract

SESSION TITLE: Interesting Presentations of Infectious Diseases SESSION TYPE: Fellow Case Reports PRESENTED ON: 10/20/2019 1:00 PM - 2:00 PM INTRODUCTION: Pulmonary Langerhans Cell Histiocytosis X (PLCH) and coccidiomycosis are two distinct disease entities with significant overlap in presenting symptoms and imaging findings; however, are rarely mentioned as differentials of one another. PLCH is a non-neoplastic smoking related condition that causes dysregulation of dendritic cells(1), while coccidiomycosis is an infection by the dimorphic fungi, Coccidioides sp., found mostly in the subtropics of North America(2). Here we describe a case of a young man who presented with symptoms consistent with both diseases (cough, fevers, chills, malaise, weight loss) and had an initial workup including a biopsy that was consistent with PLCH, but was ultimately diagnosed with Coccidiomycosis. CASE PRESENTATION: 29-year-old male smoker with no past medical history presented to our hospital with fatigue, weight loss, dyspnea, cough, and fevers for 1 month. Two weeks prior to presentation started to develop cyclical nighttime fevers and went to urgent care who gave him diagnosis of pneumonia. His symptoms worsened over the following 2 weeks despite finishing a course of antibiotics thus he presented to the hospital for further evaluation. CT showed multiple stellate pulmonary nodules with a cavitary lesion in the left lung. Extensive workup was completed including testing for fungal, bacterial, mycobacterium, and vasculitis sources which came back negative. Bronchoscopy was performed and transbronchial biopsies showed abundant proliferation of langerhans cells with strong CD1a staining (figure 1), in the absence of foreign organisms (negative methenamine silver stain) (figure 2), most consistent with a diagnosis of pulmonary histiocytosis X. He was discharged on steroids, however in one week returned with worsening cough and development of night sweats. Repeat CT showed interval increase in lymphadenopathy. Mediastinoscopy was performed revealing 5 small dense lymph nodes. An excisional biopsy was positive for coccidioides (figure 3). The patient was subsequently started on fluconazole and experienced an improvement in symptoms. DISCUSSION: This patient had risk factors, symptoms, imaging, laboratory studies, and biopsies consistent with a diagnosis PLCH; however, was ultimately diagnosed with coccidiomycosis. This case emphasizes the insidious nature that this fungal disease may take (3). Treatment of PLCH and coccidioidomycosis are diametrically opposed in that one requires immunosuppressives and the other antifungals, therefore its is crucial that one make a proper diagnosis prior to initiation of treatment (1,2). CONCLUSIONS: This case illustrates the importance of recognizing coccidiomycosis as an important differential to Pulmonary Langerhans Cell Histiocytosis X, even in a patient with with significant data supporting the diagnosis. Reference #1: BRAF V600E expression in Langerhans cell histiocytosis: clinical and immunohistochemical study on 25 pulmonary and 54 extrapulmonary cases. Roden AC Et al; Am J Surg Pathol. 2014 Apr;38(4):548-51. Reference #2: Valley Fever: Timely Diagnosis, Early Assessment, and Proper Management | Fungal Diseases | CDC.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 17 May 2017. Reference #3: Saubolle MA, Et al. Epidemiologic, clinical, and diagnostic aspects of coccidioidomycosis. Journal of Clinical Microbiology 2007; 45:26. DISCLOSURES: No relevant relationships by Kristyn Galbraith, source=Web Response No relevant relationships by Anil Ghimire, source=Web Response No relevant relationships by Isaac Huml, source=Web Response