Serological Diagnosis of Cutaneous and Visceral Leishmaniasis - Abstract
Upon deployment into war-torn endemic countries, military personnel become vulnerable to local infections. Due to the absence of preventive vaccines, we examined such situations with regard to leishmania infections. Serum samples from exposed subjects were tested by ELISA for the presence of antibodies specific to cutaneous and visceral leishmaniasis. A specific ELISA assay was constructed using Exoantigens released from cultured promastigotes. Indirect antibody levels were detected using monoclonal anti-human IgG antibody as the target, where an absorbance of 0.3 was used as the cut off. Serum was tested by ELISA initially at 1/100 dilution and further diluted and tested to determine the end-point. We report antibody profiles of cutaneous leishmania cases reported from Belize, Afghanistan, Pakistan, Iraq, and South American countries such as Peru, Ecuador, Bolivia and Guyana, Brazil, and other parts of endemic areas. The cutaneous form showed very high antibody level with end-point dilution of 1/1600. Circulating antibodies were detected in clinical cases of Leishmania brasiliensis, L. mexicana, L. viania, L. amazonensis, L. major and L. tropica suggesting that antibodies can be used as significant diagnostics. Only a few cases of visceral leishmaniasis from Malta were reported; serum was tested at 1/200 and found to be positive. High levels of antibody were detected, as opposed to previous observations where antibodies against cutaneous leishmania were either nonexistent or undetectable. Detected antibody levels were quantified and end-point determinations were made for ELISA. The antibody response generated is of very high titer and can be detected by ELISA. Specific antibodies against cutaneous and visceral leishmaniasis can be used for diagnostic purposes and results are available within few hours. Immunological testing is far quicker than the parasitology cultures and can easily be performed under field conditions, making it an ideal diagnostic for leishmaniasis.