PCR for identification of species causing American cutaneous leishmaniasis.

Parasites of the complexes Leishmania (Leishmania) mexicana, Leishmania (Viannia) braziliensis, and Leishmania (Leishmania) chagasi coexist within the same endemic areas of the American Continent. They produce similar clinical manifestations, yet not all respond well to treatment with anti-leishmania drugs. Thus, high specificity and sensitivity are needed to improve diagnosis and treatment. We developed a highly specific and sensitive polymerase chain reaction based diagnostic method that permits the identification of parasites belonging to the genus Leishmania and the differentiation between parasites belonging to the L. (L.) mexicana and L. (V.) braziliensis complexes and the identification of species of the L. (L.) mexicana complex, such as L. (L.) mexicana, Leishmania (L.) amazonensis, and Leishmania (L.) venezuelensis. This PCR permits the specific identification of Leishmania species in tissues of patients with different clinical forms of leishmaniasis. Its high sensitivity and specificity allow a precise diagnosis in lesions of patients that harbor few parasites, where the microscopic evaluation is unreliable. Additionally, this PCR could be a valuable tool for the identification of Leishmania species in mammalian reservoirs and sand fly vectors present in the American Continent.