Evaluation of the direct agglutination test (DAT) using freeze-dried antigen for the detection of anti- Leishmania antibodies in stored sera from various patient groups in Ethiopia

Abstract

Tests on a panel of 421 serum samples from Ethiopia and 11 from Europe with the direct agglutination test (DAT) and freeze-dried antigen ( Leishmania donovani 1S) showed that a cut-off titre of 1:200 or 1:400 could be employed. Using a cut-off titre of 1:400, 181 (88·3%) of 205 serum samples from visceral leishmaniasis (VL) patients tested positive, as did 5 (13·9%) of 36 sera from patients with localized cutaneous leishmaniasis, 5 (71·4%) sera from 7 patients with diffuse cutaneous leishmaniasis and 8 (89·9%) sera from 9 HIV-positive VL patients. We also found that 19 (57·6%) sera from 33 treated VL patients were still positive in the DAT at 1·5 to 5 years after treatment.