Blood, bone marrow and splenic lymphocyte subset profiles in Indian visceral leishmaniasis

We examined the lymphocyte subsets in peripheral blood, bone marrow and spleen of 11 patients with acute visceral leishmaniasis (VL) and 9 with chronic VL before and after 8 weeks of antileishmanial therapy. On admission, the CD4 cell count was depressed in the peripheral blood of acute and chronic VL cases as compared to the value in 10 normal control subjects. In contrast, CD4 cell counts were higher in the bone marrow in acute and chronic cases, and in splenic aspirates of chronic cases only, compared to normal values. The peripheral blood CD8 cell count, while normal in acute cases, was uniformly low in chronic cases. Counts of CD8 cells were also low in bone marrow of acute and chronic cases, as well as in splenic aspirates of chronic cases only. All these differences were significant (P < 0.05). After treatment, the CD4 cell count in the peripheral blood increased, but decreased in bone marrow and splenic aspirates. The CD8 cell count remained unaltered in the peripheral blood but increased significantly (P < 0.05) in bone marrow and spleen. The results suggest that in VL the peripheral blood picture may not reveal the actual T cell subset profile in the reticuloendothelial system. The changes in CD8 cell counts in the bone marrow and spleen seem to be independent, and are probably influenced by antileishmanial therapy.