TY - JOUR
T1 - Trypomastigote Excretory Secretory Antigen Blot Is Associated with Trypanosoma cruzi Load and Detects Congenital T. cruzi Infection in Neonates, Using Anti-Shed Acute Phase Antigen Immunoglobulin M
AU - Noazin, Sassan
AU - Lee, Jessica A.
AU - Malaga, Edith S.
AU - Valencia Ayala, Edward
AU - Condori, Beth J.
AU - Roca, Cristian
AU - Lescano, Andres G.
AU - Bern, Caryn
AU - Castillo, Walter
AU - Mayta, Holger
AU - Menduiña, Maria Carmen
AU - Verastegui, Manuela R.
AU - Tinajeros, Freddy
AU - Gilman, Robert H.
N1 - Funding Information:
Financial support. This work was supported by the National Institutes of Health (grants R01-AI87776 and D43-TW010074 to R. H. G. and grant D43 TW007393 to A. G. L.).
Publisher Copyright:
© The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved.
PY - 2019/1/29
Y1 - 2019/1/29
N2 - Background Congenital Trypanosoma cruzi infection accounts for an estimated 22% of new cases of Chagas disease in Latin America. However, neonatal diagnosis is challenging, as 9-month follow-up for immunoglobulin G testing is poor, quantitative polymerase chain reaction (qPCR) analysis is not routinely performed, and the micromethod misses ≥40% of congenital infections. Methods Biorepository samples from new mothers and their infants from Piura, Peru, (an area of nonendemicity), and Santa Cruz, Bolivia (an area of endemicity) were accessed. Infant specimens were assessed using the micromethod, qPCR analysis, and a trypomastigote excretory secretory antigen (TESA) blot for detection of immunoglobulin M (IgM)-specific shed acute phase antigen (SAPA) bands, using qPCR as the gold standard. Results When compared to qPCR, IgM TESA blot was both sensitive and specific for congenital Chagas disease diagnosis. Cumulative sensitivity (whether only 4 bands or all 6 bands were present) was 80% (95% confidence interval [CI], 59%-92%). Specificity was 94% (95% CI, 92%-96%) in the area of endemicity and 100% in the area of nonendemicity. SAPA bands occurred sequentially and in pairs, and parasite loads correlated highly with the number of SAPA bands present. The micromethod detected infection in fewer than half of infected infants. Conclusions The IgM TESA blot for detection of SAPA bands is rapid, relatively inexpensive, and more sensitive than the micromethod and may be a useful point-of-care test for detection of congenital T. cruzi infection.
AB - Background Congenital Trypanosoma cruzi infection accounts for an estimated 22% of new cases of Chagas disease in Latin America. However, neonatal diagnosis is challenging, as 9-month follow-up for immunoglobulin G testing is poor, quantitative polymerase chain reaction (qPCR) analysis is not routinely performed, and the micromethod misses ≥40% of congenital infections. Methods Biorepository samples from new mothers and their infants from Piura, Peru, (an area of nonendemicity), and Santa Cruz, Bolivia (an area of endemicity) were accessed. Infant specimens were assessed using the micromethod, qPCR analysis, and a trypomastigote excretory secretory antigen (TESA) blot for detection of immunoglobulin M (IgM)-specific shed acute phase antigen (SAPA) bands, using qPCR as the gold standard. Results When compared to qPCR, IgM TESA blot was both sensitive and specific for congenital Chagas disease diagnosis. Cumulative sensitivity (whether only 4 bands or all 6 bands were present) was 80% (95% confidence interval [CI], 59%-92%). Specificity was 94% (95% CI, 92%-96%) in the area of endemicity and 100% in the area of nonendemicity. SAPA bands occurred sequentially and in pairs, and parasite loads correlated highly with the number of SAPA bands present. The micromethod detected infection in fewer than half of infected infants. Conclusions The IgM TESA blot for detection of SAPA bands is rapid, relatively inexpensive, and more sensitive than the micromethod and may be a useful point-of-care test for detection of congenital T. cruzi infection.
KW - Chagas disease
KW - IgM SAPA
KW - TESA blot
KW - Trypanosoma cruzi
KW - congenital
KW - diagnosis
UR - http://www.scopus.com/inward/record.url?scp=85060802236&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85060802236&partnerID=8YFLogxK
U2 - 10.1093/infdis/jiy562
DO - 10.1093/infdis/jiy562
M3 - Article
C2 - 30252099
AN - SCOPUS:85060802236
SN - 0022-1899
VL - 219
SP - 609
EP - 618
JO - Journal of Infectious Diseases
JF - Journal of Infectious Diseases
IS - 4
ER -