Latent leprosy infection identified by dual RLEP and anti-PGL-I positivity: Implications for new control strategies

• DOI: 10.1371/journal.pone.0251631
• Publication Date: 2021-05-13T18:03:11Z
• Authors: Moises Batista da...; Wei Li; Raquel Carvalho B...; Angélica Rita Gobbo; Ana Caroline Cunh...; Tania Mara Pires ...; Erika Vanessa Oli...; Josafá Gonçalves ...; Fred Bernardes Filho; Guilherme Augusto...; Marco Andrey Cipr...; Claudio Guedes Sa...; John Stewart Spencer
• Keywords: Adult; DNA, Bacterial; Male; Adolescent; Science; Young Adult; 03 medical and health sciences; 0302 clinical medicine; Leprosy; Humans; Child; Aged; Aged, 80 and over; Antigens, Bacterial; Q; R; Middle Aged; Antibodies, Bacterial; 3. Good health; Mycobacterium leprae; Latent Infection; Medicine; Female; Glycolipids; Research Article

The number of new cases leprosy reported worldwide has remained essentially unchanged for the last decade despite continued global use free multidrug therapy (MDT) provided to any diagnosed patient. In order more effectively interrupt chain transmission, strategies will be required detect those with latent disease who contribute furthering transmission. To improve ability diagnose earlier in asymptomatic infected individuals, we examined combined two well-known biomarkers M . leprae infection, namely presence DNA by PCR from earlobe slit skin smears (SSS) and positive antibody titers -specific antigen, Phenolic Glycolipid I (anti-PGL-I) patients household contacts living seven hyperendemic cities northern state Pará, Brazilian Amazon. Combining both tests increased sensitivity, specificity accuracy over either test alone. A total 466 individuals were evaluated, including 87 newly patients, 52 post-treated 296 31 healthy endemic controls. highest frequency double positives (PGL-I+/RLEP+) detected case group (40/87, 46%) lower numbers treated (12/52, 23.1%), (46/296, 15.5%) controls (0/31, 0%). frequencies these groups reversed negatives (PGL-I-/RLEP-) (6/87, 6.9%), (15/52, 28.8%) (108/296, 36.5%) (24/31, 77.4%). data strongly suggest that are have disease, likely contributing shedding transmission their close at risk progressing clinical disease. Proposed reduce highly areas may include chemoprophylactic treatment this stop spread bacilli eventually detection rates areas.