Evaluation of diagnostic agreement between STANDARD E TB-Feron Elisa and TB-Feron FIA for tuberculosis infection in prison settings in Paraguay

Bibliographic Data

ID22070544
AuthorsSarita Aguirre (0000-0002-8752-2762, Ministerio de Salud Pública), Julieta Mendez (0000-0002-8650-8926, Universidad Columbia del Paraguay), Patricia Ríos (0000-0003-2599-282X, Instituto Regional de Investigación en Salud, Universidad Nacional de Caaguazú), Patricia Bolaños Ríos (Universidad Columbia del Paraguay), Analía Ortiz (Universidad Columbia del Paraguay), Cynthia Céspedes (Ministerio de Salud Pública), Ruth Lezcano (Ministerio de Salud Pública), Angélica Medina (0000-0003-4747-3086, Universidad Columbia del Paraguay), Renate Henning (Diazyme (United States)), Silvina Monteverde (Diazyme (United States)), Nestor Moreno (Ministerio de Salud Pública), Gladys Estigarribia (0000-0001-8058-9369, Instituto Regional de Investigación en Salud, Universidad Nacional de Caaguazú), Gladys Mercedes Estigarribia (Universidad Columbia del Paraguay), Guillermo Sequera (0000-0002-7707-1363, Universidad Columbia del Paraguay, corresponding author)
Year2026
Volume14
Pages1697667-1697667
Publication date2026-02-05
Peer ReviewedYes
Open AccessYes
TypeARTICLE
VenueFrontiers in Public Health (JOURNAL)
Journal identifiersISSN: 2296-2565 • E-ISSN: 2296-2565
PublisherFrontiers Media SA (PUBLISHER • CH)
DOI10.3389/fpubh.2026.1697667
PMID41725767
OpenAlexW7128000586
LanguageEN
References cited28

Introduction Accurate diagnosis of tuberculosis (TB) infection is essential for TB control, particularly in high-risk populations. Interferon-gamma release assays (IGRAs) are widely used for TB infection screening. This study assesses the diagnostic agreement between the STANDARDTM F TB-Feron fluorescence immunoassay (FIA) and the WHO-approved STANDARD E TB-Feron ELISA in penitentiary settings in Paraguay. Methods A cross-sectional study was conducted among 737 participants (642 incarcerated individuals and 95 staff members). Both assays were performed on the same blood samples from each participant. Agreement was assessed using the Kappa coefficient, with stratified analyses across predefined risk groups: G1, no known TB exposure ( n = 71); G2, TB exposure ( n = 525); G3, active TB ( n = 67); and G4, previously treated and cured TB ( n = 74). Results Overall positivity was 57.7% with FIA and 56.9% with ELISA. Positivity rates for FIA/ELISA were: G1 (22.9%/22.9%), G2 (57.7%/58.4%), G3 (79.1%/79.1%), and G4 (71.6%/71.6%). Overall agreement was excellent (κ = 0.851; 95% CI: 0.812–0.889; p < 0.0001). Stratified analyses showed moderate agreement in G1 (κ = 0.595) and excellent agreement in the remaining groups. Conclusion The STANDARD F TB-Feron FIA demonstrated excellent concordance with ELISA, supporting its use as a reliable alternative for TB infection screening. In addition, the FIA offers key operational advantages, including reduced hands-on time (approximately 15 min compared with several hours for ELISA), the ability to process single samples without batch runs, and the use of portable equipment requiring less laboratory infrastructure, making it particularly suitable for decentralized and resource-limited settings

Concordance · Prison · Tuberculosis · Tuberculosis diagnosis · Infectious Diseases and Tuberculosis · Pneumonia and Respiratory Infections · Tuberculosis Research and Epidemiology