PULMONARY CYSTIC ECHINOCOCCOSIS

TOPIC: Chest Infections TYPE: Medical Student/Resident Case Reports INTRODUCTION: A lung nodule in an elderly patient almost always raises concern for cancer, irrespective of risk factors. While cancer remains foremost the clinicians mind, a thorough occupational history may provide clues implicating different diagnosis more uncommon etiologies nodule, such as our case. CASE PRESENTATION: 74 year old male with hypertension and prostate remission presented to his primary care physician 3 months dry cough chest pain. He had no smoking history. Vital signs showed blood pressure 170/93 mmHg, other vital within normal limits. Physical examination laboratory analysis was unrevealing. radiograph 2.9 centimeter (cm) left lower lobe nodule. Computerized tomography scan (CT) demonstrated lobular measuring 3x2x2 cm smooth margins. Fluorodeoxyglucose (FDG)-positron emission (PET) failed reveal any avid regions. robotic wedge resection performed, revealing cystic membranous spherical lesion that spilled fluid when incised. Frozen section pathology hydatid cyst containing innumerable Echinococcus granulosus organisms. started on albendazole therapy. It later discovered Army deployed rural southern Vietnam 5 youth, where he working farms wild animals, swimming through dirty water drinking contaminated water. When back United States, did cross country trips, riding mules Utah. also lived Hawaii years dog. serology negative. Repeat CT lesions liver lesions. The completed 1 month total has recovered. DISCUSSION: Only minority involvement E. infection coincides cysts (20-40%). lobes are commonly involved (60%). Patients be asymptomatic, have cough, hemoptysis or even anaphylaxis (1). Differentiating unruptured from pulmonary malignancy, can difficult radiographically. One Turkish study reports 7 patients 4 span who surgical removal presumed malignancy but were found (2), common occurrence endemic areas. imaging usually reveals homogenous well-circumscribed lobulated If bronchus is eroded, air introduced into appear crescent (crescent sign) (3). CONCLUSIONS: Obtaining extensive travel exposure substantially alter differential lesions, assist diagnostic management considerations. REFERENCE #1: Morar R, Feldman C. Pulmonary echinococcosis. Eur Respir J. 2003 Jun;21(6):1069-77. doi: 10.1183/09031936.03.00108403. PMID: 12797504. #2: Çobanoğlu U, Aşker S, Mergan D, Sayır F, Bilici Melek M. Diagnostic Dilemma Hydatid Cysts: Tumor-Mimicking Cysts. Turk Thorac 2015 Oct;16(4):180-184. 10.5152/ttd.2015.4606. Epub Oct 1. 29404100. #3: Garg MK, Sharma M, Gulati A, Gorsi Aggarwal AN, Agarwal Khandelwal N. Imaging cysts. World J Radiol. 2016 Jun 28;8(6):581-7. 10.4329/wjr.v8.i6.581. 27358685. DISCLOSURES: No relevant relationships by Oleg Epelbaum, source=Web Response Daniel Greenberg, Ravi Manglani, Fouzia Shakil, Helena Tomac Pavosevic,