Sensitivity of the polymerase chain reaction for the diagnosis of cutaneous leishmaniasis due to Leishmania (Viannia) guyanensis

The sensitivity of the polymerase chain reaction (PCR) in 35 consecutive ou tpatients with cutaneous leishmaniasis caused by Leishmania (Viannia) guyan ensis was evaluated using, as gold standard, the in vitro isolation of the parasite through culture of aspirates of the cutaneous ulcers. All isolates were identified using electrophoretic enzyme analysis. Patients were mainl y young males with recent onset disease without prior specific treatment. P CR was performed using DNA extracted from fresh frozen biopsies of cutaneou s ulcers. The reaction used a pair of oligonucleotides that amplify the con served region of the minicircle molecule. PCR showed 100% sensitivity (95% CI from 90.0 to 100.0). These results were similar to the visualization of amastigotes in imprint preparations of cutaneous biopsy tissue and the inoc ulation of biopsy material in golden hamsters. Despite the high sensitivity of the PCR, in this particular clinical setting of cutaneous leishmaniasis caused by L. (V.) guyanensis in the Brazilian Amazon, it appears that the method of choice for diagnosis should be the direct visualization of amasti gotes using imprint preparations and the PCR reserved for those patients wi th negative imprint results. (C) 2001 Elsevier Science B.V. All rights rese rved.