Pre- & post-treatment evaluation of immunological features in Indian visceral leishmaniasis (VL) patients with HIV co-infection.

Background & Objective: The risk of human immunodeficiency virus (HIV) co-infection in patients with visceral leishmaniasis (VL) or kala-azar in endemic areas has posed a major challenge in control programmes. We undertook this study to identify the high risk groups vulnerable to Leishmania-HIV co-infection in VL endemic State of Bihar, India. Further, immunological responses were also evaluated in these patients before and after treatment for VL to see the immune impairment associated with CD4 T cell count.
Methods: A total of 1511 subjects attending Voluntary Counselling and Testing Centre (VCTC) at Patna, Bihar were included in this study. VL was confirmed by splenic or bone marrow aspirates testing for parasite. HIV states was confirmed by two kits. Immunological parameters (CD4, CD8, IFN-gamma, IL-4) were studied in co-infection patients.
Results: Of the 280 (18.53%) HIV-positive individuals, eight were diagnosed serologically and pathologically as VL patients co-infected with HIV. The humoral and cellular immune responses were evaluated in 18 Indian VL patients with (n = 8) or without HIV (n = 10) and 10 HIV seropositive subjects. Among the eight confirmed cases of VL, false negative direct agglutination test (DAT) result was observed in two who had HIV co-infection (sensitivity 80%), while none in 10 other VL cases who were HIV negative (sensitivity 100%). A very low CD4 cell count was observed in VL cases that had HIV co-infection compared to HIV negative VL or controls. All VL cases with or without HIV infection had lower Th1/Th2 ratio compared to controls. VL patients with or without HIV infection responded well to anti-leishmanial/anti-retroviral therapy with considerable degree of immunological reconstitution.
Interpretation & Conclusion: A different immune response was noticed in patients with co-infection of HIV and Leishmania. Anti-leishmanial drug treatment led to improvement in immunological response in co-infected patients. Further studies need to be done to see the effect of combined therapy for VL and HIV on immunological parameters in these patients.