Immunopathology of nephritis in Africa.

Clinicians have long suspected a relationship between malaria and nephritis in Africa. The results of tests made several years ago suggested that the relationship might be an immunological one. This memorandum discusses clinical, epidemiological, morphological, and immunopathological aspects of malaria-associated nephropathy, will special emphasis on immunological investigations. Immunofluorescence studies on renal biopsies from patients with the nephrotic syndrome and Plasmodium malariae parasitaemia have shown the presence of immunoglobulin (Ig) deposits with certain complement components on glomerular basement membranes. IgG with anti-P. malariae specificity has been found in eluates of kidney tissue from such patients and P. malariae antigen was identified in the glomerular basement membrane by immunofluorescence studies. These observations support the view that the nephropathy associated with P. malariae infections is a form of immune complex nephritis initiated by circulating P. malariae antigens and anti-P. malariae antibodies. Additional support is obtained from electron microscope studies, which show that electron-dense material is associated with the glomerular basement membrane in certain diseases of the kidney in which immune complexes have been detected in glomeruli by immunofluorescence methods. The view that malarial nephritis is a form of immune complex disease should be useful in stimulating new approaches to the study of the pathogenesis of both the initiating and the perpetuating immunopathological lesion.