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Cryptococcus is an opportunistic pathogenic fungus and is the major cause of fungal meningitis. The cryptococcal antigen (CrAg) lateral flow assay (LFA) is an immunochromatographic test system that has simplified diagnosis as a point-of-care test. In this study, we evaluated the diagnostic performance of Cryptococcal capsular polysaccharide detection FungiXpert (Genobio Pharmaceutical, Tianjin, China) using serum and cerebrospinal fluid (CSF) samples for the diagnosis of cryptococcosis and investigated the cross-reaction of the assays to pathogenic fungi and bacterium by comparing it to the U.S. Food and Drug Administration (US FDA)-approved IMMY CrAg LFA. Eighty CSF and 119 serum/plasma samples from 158 patients were retrospectively collected to test for qualitative or semi-quantitative detection of CrAg. Cross-reaction of the assays was tested using 28 fungi and 1 bacterium. Compared to IMMY CrAg LFA, the FungiXpert LFA demonstrated 99.1% sensitivity and 98.9% specificity in the qualitative test. In the 96 semi-quantitative CrAg assay results, 39 (40.6%) test titers of FungiXpert LFA were 1–2 dilutions higher than those of IMMY CrAg LFA. The Intraclass Correlation Coefficient of the Semi-quantitative results of CrAg titer tests via the two assays was 0.976. Similar to IMMY CrAg LFA, FungiXpert LFA showed cross-reactivity with Trichosporon asahii. Compared with the IMMY CrAg LFA, the FungiXpert LFA showed an equal, yet, excellent performance. However, it is important to note that these two assays have potential cross-reactivity to T. asahii when diagnosing patients. FungiXpert LFA is a rapid screening method for the effective and practical diagnosis and treatment of cryptococcosis. Lay summary The FungiXpert LFA was developed to diagnose fungal meningitis caused by Cryptococcus yeasts, by using serum or cerebrospinal fluid. It was compared to an existing lateral flow assay (LFA). The FungiXpert LFA performed well in qualitative and semi-quantitative tests.

Cryptococcus is the major pathogen that causes fungal meningitis. In the People's Republic of China, especially in the Southwest area, cryptococcal meningitis (CM) in HIV-uninfected patients is more common than in HIV-infected patients. We compared clinical features and laboratory data pertaining to CM in patients with different immunological statuses. Demographic data, clinical manifestations, and laboratory data from inpatients in West China Hospital Sichuan University were collected from June 2009 to June 2014. Patients were grouped according to HIV status. Continuous variables were evaluated by Student t-test or Wilcoxon rank sum tests. Categorical variables were analyzed by χ2 test. Among 85 patients with CM were identified, 53 (62.4%) were HIV-uninfected patients. CM occurred more frequently in males in the HIV-infected group. Compared with HIV-infected patients, HIV-uninfected patients had more leukocytes in their blood and more leukocytes and protein in cerebrospinal fluid. More HIV-uninfected patients had increased cerebrospinal fluid (CSF)/serum albumin ratios, while intrathecal immunoglobulin G (IgG) synthesis was significantly increased. The rate of in-hospital mortality of HIV-infected CM patients was higher. Clinical signs are similar between HIV-uninfected and HIV-infected CM patients. Fewer leukocytes and protein was detected in the CSF and lower local synthesis of IgG in the central nervous system in HIV-infected patients, which reflects their diminished immune response. These characteristics should be noted in order to avoid misdiagnosis. Meningeal enhancement and intrathecal IgG synthesis in the HIV-uninfected group was significantly higher, that may be performance of aggressive inflammatory response and might contribute to a better outcome.