Diagnostic accuracy cohort study and clinical value of the Histoplasma urine antigen (ALPHA Histoplasma EIA) for disseminated histoplasmosis among HIV infected patients: A multicenter study.

• Published in: PLOS Neglected Tropical Diseases
• Main Authors: Pedro Torres-González, María Dolores Niembro-Ortega, Areli Martínez-Gamboa, Víctor Hugo Ahumada-Topete, Jaime Andrade-Villanueva, Javier Araujo-Meléndez, Alberto Chaparro-Sánchez, Brenda Crabtree-Ramírez, Sofia Cruz-Martínez, Armando Gamboa-Domínguez, Oscar I Flores-Barrientos, Jesús Enrique Gaytán-Martínez, Luz Alicia González-Hernández, Christian Hernández-León, Víctor Hugo Lozano-Fernandez, Marisol Manríquez-Reyes, Martin Magaña-Aquino, Pedro Martínez-Ayala, Juan Pablo Ramírez-Hinojosa, Andrea Rangel-Cordero, Norma Erendira Rivera-Martínez, Edgardo Reyes-Gutiérrez, Gustavo Reyes-Terán, Patricia Rodríguez-Zulueta, Jesús Ruíz-Quiñones, Janeth Santiago-Cruz, Nancy Guadalupe Velázquez-Zavala, José Sifuentes-Osornio, Alfredo Ponce de León
• Format: Article in Journal/Newspaper
• Language: English
• Published: Public Library of Science (PLoS) 2018
• Subjects: Arctic medicine. Tropical medicine; RC955-962; Public aspects of medicine; RA1-1270; Arctic; Eia
• Online Access: https://doi.org/10.1371/journal.pntd.0006872; https://doaj.org/article/e28a14d7b81d4c09bd62e0cac6e1d77d

BACKGROUND:The Histoplasma urine antigen (HUAg) is the preferred method to diagnose progressive disseminated histoplasmosis (PDH) in HIV patients. In 2007, IMMY ALPHA Histoplasma EIA was approved for clinical for on-site use, and therefore useful for regions outside the United States. However, ALPHA-HUAg is considered inferior to the MVista-HUAg which is only available on referral. We aim to evaluate the diagnostic accuracy of ALPHA-HUAg. METHODOLOGY/PRINCIPAL FINDINGS:We conducted a multicenter, prospective, diagnostic test study in two secondary and eight tertiary-care facilities in Mexico. We included HIV patient with PDH suspicion and evaluated ALPHA-HUAg diagnostic accuracy using as reference standard the Histoplasma capsulatum growth on blood, bone marrow, and tissue cultures or compatible histopathologic exam (PDH-proven). We evaluated the results of 288 patients, 29.5% (85/288; 95% confidence interval [CI], 24.3-35.1) had PDH. The sensitivity of ALPHA-HUAg was 67.1% (95% CI, 56-76.8%) and the specificity was 97.5% (95% CI, 94.3%-99.1%). The positive likelihood ratio was 27.2 (95% CI; 11.6-74.4). In 10.5% of the PDH-proven patients, a co-existing opportunistic infection was diagnosed, mostly disseminated Mycobacterium avium complex infection. CONCLUSIONS/SIGNIFICANCE:We observed a high specificity but low sensitivity of IMMY-HUAg. The test may be useful to start early antifungals, but a culture-based approach is necessary since co-infections are frequent and a negative IMMY-HUAg result does not rule out PDH.