Detection of new endemic areas of cutaneous leishmaniasis in Pakistan: a 6-year study

Background Cutaneous leishmaniasis (CL) is endemic in Pakistan and is widely spreading. Recently, an outbreak of the disease was observed in the region. We report some new endemic areas of CL in the country. Methods A total of 1210 cases of CL who visited our department from 1996 to 2001 are reported. Among them, 760 were residents of the Jacobabad, Larkana, and Dadu districts of Sindh province and had never previously traveled to endemic areas. These districts have never been reported/recognized as endemic for CL. Others were residents of endemic areas of Balochistan province. Diagnosis was made on clinical presentation; a giemsa-stained smear test and histopathological results. All the cases were treated with the meglumine antimoniate 600 mg/day (adults) and 15 mg/kg/day (children) intramuscularly for 20 consecutive days. Results All the patients were aged between 2.5 months and 65 years. Three hundred and ninety-two patients were females and 368 were males. Duration of the disease ranged from 2 to 18 months. Most of the patients had a single lesion on the face and/or extremities. Clinically, the disease was classified as: dry papular type, 407 cases; dry ulcerative type, 335 cases; and wet ulcerative type, 18 cases. No cases of muco-cutaneous or visceral leishmaniasis were found during this period. Smear testing was positive in 845 cases, while 365 cases were histopathologically positive. An ultrastructural study was performed using specimens of a few of the cases. Leishmania parasites were detected in the dermal tissues as well as in the macrophages. Conclusions We propose that the Jacobabad, Larkana and Dadu districts could be considered endemic for CL. Wet- and dry-type lesions indicate the presence of both Leishmania tropica and L. major in this tropical region.