HIV infection compounds the lymphopenia associated with cerebral malaria in Malawian children.

Aim: Cerebral malaria (CM), unlike severe malarial anemia (SMA), has previously been characterized by pan-lymphopenia that normalizes in convalescence, while HIV infection is associated with depletion of CD4(+) T cells. In this study, we investigate whether HIV infection in Malawian children exacerbates the pan-lymphopenia associated with CM. Methods: We investigated the absolute and percentage lymphocyte-subset counts and their activation and memory status in Malawian children presenting with either CM who were HIV-uninfected (n=29), HIV-infected (n=9), or SMA who were HIV-uninfected (n=30) and HIV-infected (n=5) in comparison with HIV-uninfected children without malaria (n=42) and HIV-infected children without malaria (n=4). Results: HIV-infected CM cases had significantly lower absolute counts of T cells (P=0.006), CD4(+) T cells (P=0.0008), and B cells (P=0.0014) than HIV-uninfected CM cases, and significantly lower percentages of CD4(+) T cells than HIV-uninfected CM cases (P=0.005). HIV-infected SMA cases had significantly lower percentages of CD4(+) T cells (P=0.001) and higher CD8(+) T cells (P=0.003) in comparison with HIV-uninfected SMA cases. HIV-infected SMA cases had higher proportions of activated T cells (P=0.003) expressing CD69 than HIV-uninfected SMA cases. Conclusion: HIV infection compounds the perturbation of acute CM and SMA on lymphocytes, exacerbating subset-specific lymphopenia in CM and increasing activation status in SMA, potentially exacerbating host immunocompromise.