Talaromyces marneffei Mp1p Antigen Detection may Play an Important Role in the Early Diagnosis of Talaromycosis in Patients with Acquired Immunodeficiency Syndrome

Talaromycosis is a life-threatening fungal disease commonly seen in patients with acquired immunodeficiency syndrome (AIDS), which is endemic in Southern China and Southeast countries. The diagnostic methods available for talaromycosis are relatively time-consuming and yield a high mortality. Therefore, early diagnosis of talaromycosis is extremely important. We aimed to determine a potential method for assisting in its early diagnosis. A total of 283 patients with AIDS admitted to our hospital were prospectively included in this cross-sectional study and divided into those with Talaromyces marneffei (TSM group, n = 93) and those without Talaromyces marneffei (non-TSM group, n = 190). The diagnostic accuracy of the Mp1p enzyme immunoassay (EIA), galactomannan (GM) assay, and blood culture performed within 3 days of hospitalisation were evaluated, using talaromycosis confirmed by culture and/or pathology as the gold standard. The positivity rates in the Mp1p EIA, GM assay, and blood culture were 72%, 64.5%, and 81.7%, respectively, in the TSM group. The sensitivity, specificity, and positive and negative predictive values of the Mp1p EIA were 72.0% (67/93), 96.8% (184/190), 91.8% (67/73), and 87.6% (184/210), respectively. The Mp1p EIA showed a substantial agreement with the gold standard (kappa: 0.729) and superiority to the GM assay (kappa: 0.603); it also showed a superior diagnostic accuracy in the patients with CD4+ counts of < 50 cells/µL compared to those with CD4+ counts ranged from 50–100 cells/µL. The Mp1p EIA has the advantage of assisting in the early diagnosis of talaromycosis in patients with AIDS, especially those with low CD4+ counts.