Impaired Th1 Response Is Associated With Therapeutic Failure in Patients With Cutaneous Leishmaniasis Caused by Leishmania braziliensis.

Background: Leishmania skin test (LST) evaluates the delayed type hypersensitivity to Leishmania antigens (LA) and has been used for diagnosis of cutaneous leishmaniasis (CL). In CL patients LST is usually positive but a small percentage have negative LST. The aim of this study was to determine the clinical and immunologic features and response to antimony therapy in LST-negative CL patients.