SERODIAGNOSIS AND EPIDEMIOLOGY OF VISCERAL LEISHMANIASIS IN TURKEY

Infantile Mediterranean visceral leishmaniasis (IVL) and anthroponotic cutaneous leishmaniasis (ACL) have long been known to exist in the we stern and southeastern Turkey, respectively. To further study these an d other related diseases, a recombinant antigen (rK39) specific to VL was used in an ELISA for serodiagnosis of selected patients and for sc reening dog reservoir populations in several endemic sites. Among 24 c onfirmed VL cases from western Turkey, the rK39 ELISA proved to be mor e sensitive than a combination of cultivation and microscopy of bone m arrow aspirates. The specificity of rK39 for leishmaniasis was demonst rated by its lack of cross-reactivity with sera from other human disea ses in the same sites. Interestingly, six of the 83 parasitologically proven ACL cases from southeast Turkey were also rK39 positive. The en d point titers of the positive VL and CL cases vary from 10(-2) to 10( -5) and from 10(-2) to 10(-3), respectively. The rK39 ELISA was also u sed to screen 494 apparently healthy dogs from Urfa in southeast Turke y, Manisa/Alasehir near the Aegean Sea, and Karabuk near the Black Sea . Eighteen rK39-positive cases (3.6%), all from the latter two areas, were found to have varying endpoint titers (10(-2)-10(-4)). The high t iters predicted increased severity and frequency of the clinical sympt oms (i.e., lymphadenopathy, depilation, skin lesion, weight loss and/o r death), which were manifested subsequently in 16 of these 18 cases. In addition, more positive canine cases were diagnosed by the rK39 ELI SA preclinically than the procedures to detect parasites post-symptoma tically in the lymph node aspirates. The use of the rK39 ELISA as a se nsitive tool makes it possible to demonstrate coendemicity of canine a nd human VL, as expected in the case of IVL. The results also point to the possible presence of additional VL types in western Turkey and cu tanovisceral type in the southeast part of this country.