PCR detection of Leishmania in skin biopsies

Cutaneous leishmaniasis (CL) is an endemic disease and one of the major health problems in Morocco. In 2006, the recorded total number of cases of CL was 3361, occurring predominantly in the rural population. A new and more sensitive diagnostic technique than current methods used is needed in this setting. The aim of this study was to assess the efficacy of polymerase chain reaction (PCR) to detect leishmanial parasites in skin biopsies of patients from different areas of endemicity in Morocco.

Biopsies from 26 patients with cutaneous ulcers suggestive of leishmaniasis were analysed by PCR using primers from the small subunit ribosomal gene. The ability of PCR to detect Leishmania was compared with smear-stained and in vitro culture.

PCR exhibited superior sensitivity (84,6%) compared with direct microscopy smear (69,2%) and in vitro culture (69,2%). Our PCR assay also showed good specificity (100%).

PCR should be considered a valuable, sensitive, and faster diagnostic tool in the diagnosis of cutaneous leishmaniasis, especially for those patients with negative parasitologic examination.