Boletín de malariología y salud ambiental. Vol. XLVII, Nº 1, enero-julio, 2007
Abstract
Three serological tests (ELISA, IFAT, DAT) were evaluated using sera from selected
individuals with different American cutaneous leishmaniasis (ACL) clinical conditions. Reactivity in
at least 2 of the 3 named tests was established as a criterion for declaring a patient as sero-positive.
Prior to serological testing, people were diagnosed by clinical (presence of lesion = pl or scar=Sc),
parasitological (presence of parasites =pp), immunological (LST) and molecular (PCR) methods. For
a statistical comparison of the evaluated tests 4 groups of people were made up: 1) patients with
active leishmanial lesion (n=44; pl, pp, +LST, +PCR); 2) patients who had recovered from leishmanial
infection (n=43; Sc, +LST, +PCR); 3) asymptomatic individuals from endemic areas showing evidence
of having contacted Leishmania-parasites (n=40; +LST, +PCR) and 4) Leishmania-negative people
from the above localities where leishmaniasis is endemic and living under the same risk conditions,
considered as healthy controls (n=104; -LST, -PCR). Considering the above-established criteria
for sero-positives, the analysis of the results obtained with the 3 tests employed revealed very low
sensitivity values. Seropositive figures of 50% were recorded for the first group, 9% for the second
group, and 12.5% for the third group. Statistical analysis also revealed a low positive predictive value
(PPV=0.73), a low negative predictive value (NPV=0.49), and a low kappa coefficient value (k=0.114).
The present results raise questions about the use of the 3 conventional serological tests compared
here to detect ACL at any clinical [email protected]@[email protected]
