02026nas a2200325   4500000000100000008004100001260001200042653000800054653001000062653001200072653001700084653001400101653001400115653002200129653001200151100001200163700001800175700001200193700001400205700001500219700001200234700001300246700002100259245012400280856007000404300001100474490000600485520119500491022001401686       2021                            d  c01/202110aIgA10aLID-110aNDO-HSA10aROC analysis10abiomarker10adiagnosis10ahousehold contact10aleprosy1 aSilva K1 ade Oliveira E1 aElias C1 aPereira I1 aPinheiro R1 aSarno E1 aDuthie M1 aCouto Teixeira H00aSerum IgA Antibodies Specific to M. leprae Antigens as Biomarkers for Leprosy Detection and Household Contact Tracking.  uhttps://www.frontiersin.org/articles/10.3389/fmed.2021.698495/pdf  a6984950 v83 a<p>Leprosy remains endemic in several developing countries, such as India and Brazil, in part due to delayed diagnosis that facilitates ongoing transmission. Although immunoglobulins against several  antigens have been indicated for the early diagnosis, and IgA participates in the early stages of leprosy and in subclinical infection, relatively little research has examined anti-M. leprae IgA responses. Here, we investigated serum IgA reactivity against NDO-HSA, LID-1 and NDO-LID, in paucibacillary (PB) and multibacillary (MB) patients and their household contacts, using enzyme-linked immunosorbent assay (ELISA). Diagnostic accuracy of each ELISA was evaluated by receiver operating characteristic (ROC) curve analysis. Our data reveal elevated IgA serum levels against the three  specific antigens in MB patients, whereas IgA reactivity in PB patients was increased only to NDO-HSA. Further, MB and PB household contacts displayed higher IgA reactivity to NDO-HSA than non-endemic controls. Our data suggest measurement of serum IgA against NDO-HSA as an additional tool in the diagnosis and classification of the disease, with potential utility for household contact follow-up.</p>  a2296-858X