Table 1.

Comparison of Conventional and Detection Polymerase Chain Reaction (PCR) Targeting Trypanosoma cruzi Kinetoplast DNA in Specimens Obtained from 10 Infants Born in the Hospital Universitario Japones, Santa Cruz, Bolivia

	Conventional diagnosisa		PCR results in specimens from the first 90 days of life
Infant	Means of diagnosis	Age at conventional diagnosis, days	Age at first PCR-positive specimen, days	Umbilical tissue	Cord blood	7 days	21 days	30 days	90 days
Infant 15	Serological testing	271	30	−	−	ND	ND	+	+
Infant 19	Micromethodb	33	Birth	+	+	−	+	+	ND
Infant 120	Missed	Missed	Birth	+	+	+	ND	ND	ND
Infant 179	Micromethod	6	6	ND	ND	+	+	ND	ND
Infant 203	Micromethod	20	Birth	ND	+	+	+	ND	ND
Infant 218	Serological testing	275	Birth	+	+	+	−	+	+
Infant 270	Micromethod	189	Birth	+	+	+	+	+	+
Infant 342	Micromethod	103	Birth	+	−	−	−	−	+
Infant 471	Micromethod	8	Birth	+	+	+	+	ND	ND
Infant 478	Serological testing	278	Birth	+	−	−	−	−	+

NOTE. The mean age at diagnosis by conventional techniques was 131 days, compared with 4 days for molecular diagnosis. ND, not done; +, positive; −, negative.

^aConventional diagnosis defined by visualization of parasites in concentrated blood specimens at any age, or positive results of 2 conventional IgG serological tests at 270 days (9 months) of age.

^bThe micromethod is the standard assay for early diagnosis of congenital infection. The assay consists of concentration by centrifugation of 4–6 microhematocrit tubes of heparinized blood, followed by microscopic examination of the buffy coat layer. See text for further description.