Molecular and histological tools to diagnose an imported case of American cutaneous leishmaniasis in Cuba

Abstract

Leishmaniasis represents a polymorphous group of diseases caused by around 20 different species of Leishmania parasite. Increases in the number of cases of leishmaniasis reported as a consequence of the growth in travel and migration are of concern to epidemiologists and are diagnostically challenging in non-endemic areas. Molecular and histological analyses of a paraffin-embedded skin biopsy were used in parallel to detect Leishmania parasites in a Cuban woman with suspicious lesions arriving in Cuba from Venezuela. Primers based on the 18S fragment of ribosomal ribonucleic acid (rRNA) and heat shock protein 70 genes (hsp70) were used for molecular detection. Histological studies detected the presence of the parasite. A small fragment of Leishmania DNA was amplified by polymerase chain reaction (PCR) targeting the 18S fragment using, for the first time, nucleic acid obtained from paraffin-embedded tissue as a template. Amplification of a larger fragment from the hsp70 gene did not occur. The detection of Leishmania DNA from paraffin-embedded tissue by means of 18S-targeted PCR is a feasible approach to diagnosis. In combination with classical methods such as histology, the molecular detection of the parasite was demonstrated to be useful in confirming Leishmania infection in a traveler.