Early diagnosis of congenital Trypanosoma cruzi infection using PCR, hemoculture, and capillary concentration, as compared with delayed serology.
Congenital Trypanosoma cruzi infection is a highly pathogenic and underreported condition. Early recognition is essential for effective treatment. Umbilical chord blood from newborns (n = 302) to infected mothers was analyzed with microhematocrit, hemoculture, and PCR methods. Each subject was then followed serologically. In calibrated suspensions of T. cruzi in blood, the sensitivity of PCR was 27-fold higher than hemoculture. However, this advantage was not reflected during routine testing of samples from maternities, partly because of the uneven distribution of few parasites in small samples. Levels of detection of congenital infection were 2.9% (8/272) for microhematocrit, 6.3% (18/287) for hemoculture, 6.4% (15/235) for PCR, and 8.9% (27/302) for cumulated results. Evaluation against the standard of delayed serology indicates that the regular application of PCR, hemoculture, and microhematocrit to blood samples allows the rapid detection of about 90% of the congenitally infected newborns, in samples that can be obtained before the mother and child leave the maternity ward.
Instituto de Patología Experimental, Facultad de Ciencias de la Salud, Universidad Nacional de Salta, Argentina.
María Celia
MC
Mora
Olga
O
Sanchez Negrette
Diego
D
Marco
Alejandra
A
Barrio
Mirella
M
Ciaccio
María Asunción
MA
Segura
Miguel A
MA
Basombrío
D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D014355:Chagas Disease / Q000151:congenital* / Q000175:diagnosis*; D016054:DNA, Protozoan / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005188:False Negative Reactions; D005312:Fetal Blood / Q000469:parasitology; D006400:Hematocrit; D006801:Humans; D007231:Infant, Newborn; D018512:Parasitemia / Q000469:parasitology; D016133:Polymerase Chain Reaction / Q000379:methods*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014349:Trypanosoma cruzi / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*
D000913:Antibodies, Protozoan; D016054:DNA, Protozoan