EVALUATION OF PCR FOR DIAGNOSIS OF VISCERAL LEISHMANIASIS

An evaluation of Leishmania PCR was performed with bone marrow, lymph node, and blood samples from 492 patients, 60 positive controls, and 9 0 negative controls, Results were compared with microscopy results for Giemsa-stained smears, PCR and microscopy of lymph node and bone marr ow aspirates from patients with microscopically confirmed visceral lei shmaniasis (VL) were equally sensitive, However, in patients clinicall y suspected of having VL and in whom parasites could not be demonstrat ed bg microscopy, PCR was positive for 12 of 23 (52,2%) lymph node asp irates and 8 of 12 (66.7%) bone marrow aspirates, thus confirming the clinical diagnosis of VL, With PCR on filler paper, Leishmania DNA was detected in the blued of 33 of 47 (70%) patients with confirmed VL an d in 2 of 11 (19%) patients suspected of having VL, Positive PCR resul ts were more frequently found for blood samples on filter paper than f or samples stored in EDTA. In conclusion PCR is a more sensitive metho d than microscopy for the detection of Leishmania in lymph node and ho ne marrow aspirates, being especially useful for the confirmation of c ases of suspected VL. Blood from a finger prick may be used for the in itial FCR screening of people suspected of having VL. If the PCR of bl ood is negative, one should perform PCR with lymph node and/or bone ma rrow material, because PCR with these materials is more often positive .