Serum Cryptococcal Antigen Confirmed Pulmonary Cryptococcosis in an Immune-competent Adult Firstly Misdiagnosed of Tuberculosis from a Lung Biopsy: a Case Report and Literature Review

iBackground:/iCryptococcal pneumonia is an uncommon lesion in immune-competent adults. Histological evidence of Cryptococcus neoformans is a gold criterion for diagnosis. Here we report a case firstly misdiagnosed as tuberculosis from a lung biopsy.iMethods:/iChest computed tomography (CT) scan and CT-guided puncture were performed for diagnosis and blood tests explored for the latent etiology.iResults:/iChest CT scan images showed multiple nodules in the left peripheral lower lobe. Histopathology demonstrated multiple granulomatous inflammatory response lacking evidence of Cryptococcus neoformans, acid-fast staining was negative, serum cryptococcal antigen was positive.iConclusions:/iSerum cryptococcal antigen has high specificity in cryptococcal pneumonia.