Association of HIV-Induced Immunosuppression and Clinical Malaria in Nigerian Adults.

Despite the growing body of evidence on the interaction between HIV and malaria in sub-Saharan Africa, there is a dearth of data on clinical malaria in HIV-infected patients in Nigeria. We determined the burden of clinical malaria in HIV-infected adult Nigerians and further investigated the association between their immunological status and the rates of clinical malaria. Ninety seven antiretroviral treatment-naïve HIV-infected adults were enrolled in a cross-sectional study from August to December, 2009. The participants had a complete clinical evaluation, thick and thin blood films for malaria parasites and CD4 cell count quantification. Clinical malaria was defined as having fever (temperature ≥ 37.5°C or history of fever within 48 hours) and a malaria parasite density above the median value obtained for subjects with co-existing fever and parasitaemia. Clinical malaria was diagnosed in 10 out of 97 patients (10.3%). Lower CD4 cell counts were associated with increasing rates of clinical malaria which was 0% at CD4 cell count of ≥ 500, 2.6% at 200-499 and 30% at <200 cells/µL (χ(2) = 18.3, p = 0.0001). This association remained significant after controlling for other factors in a multivariate analysis (AOR=22.98, 95% C.I: 2.62-20.14, p = 0.005). An inverse relationship between CD4 cell count and parasite density was demonstrated (regression co-efficient = - 0.001, p = 0.0002). More aggressive malaria control measures are highly needed in severely immunosuppressed HIV-infected patients.