ObjectiveTo evaluate the diagnostic value of cryptococcal antigen lateral flow immunochromatographic assay (CrAg-LFA) in bronchoalveolar lavage fluid (BALF) among pulmonary cryptococcosis (PC) patients.MethodsPatients from the Zhongshan Hospital, Xiamen University, Zhangzhou Municipal Hospital of Fujian Medical University, Second Affiliated Hospital of Fujian Medical University, and Quanzhou First Hospital of Fujian Medical University were enrolled prospectively from March 2015 to October 2018. They were confirmed without human immunodeficiency virus infection and were divided into non-PC group (236 cases) and PC group (72 cases). The PC was definitely diagnosed by histopathological evidence from lung biopsy. The CrAg-LFA and culture were performed in both the serum and BALF among the enrolled patients.ResultsAmong 72 PC patients, 54 had a positive serum CrAg-LFA, 1 had positive serum culture; 67 patients had a positive BALF CrAg-LFA, 9 had positive BALF culture. Among the non-PC group, only 1 patient had a weak positive serum CrAg-LFA, none had positive serum culture of PC; 236 cases non-PC patients underwent BALF CrAg-LFA detection, none had a positive BALF CrAg-LFA; none of the 121 cases who had BALF culture yielded a positive result in PC. The sensitivity, specificity, positive predicted value, and negative predicted value in serum were 75.0%, 99.6%, 98.2%, and 92.9%, respectively. Those above mentioned values in the BALF yielded 93.6%, 100.0%, 100.0%, and 97.9%, respectively. Among the PC group, the sensitivity was higher in BALF than that in serum (χ2=8.745, P<0.05).ConclusionsThe CrAg-LFA is a simple and rapid diagnostic method for PC. The diagnostic value of CrAg-LFA in the BALF is superior to that in serum and fungal culture among the PC patients. The positive BALF CrAg-LFA result is consistent with mycological positive results.