Protein AA amyloidosis in Nigeria.

Eight cases of multi-system amyloid have been found in 4235 autopsies (0.2%) performed at University College Hospital, Ibadan, Nigeria between 1970 and 1979. Blocks and sections of seven cases showed the organ distribution associated with secondary amyloid, involving kidney, spleen and liver. Potassium permanganate oxidation prior to Congo Red staining showed that all seven cases contained protein AA amyloid. Five patients had tuberculosis but in two patients there was no recognized cause, idiopathic AA amyloid. Patients usually presented with nephrotic syndrome or renal failure and hypertension was absent. There appears to be a low incidence of amyloidosis in Africans, despite the occurrence of a large number of potential amyloidogenic stimuli, indicating the importance of individual host reactivity and failure of amyloid degradation in the causation of amyloidosis.