Spontaneous mesangioproliferative glomerulonephritis in pigtailed macaques (Macaca nemestrina).

Mesangioproliferative glomerulonephritis was found in 28 of 113 pigtailed macaques (Macaca nemestrina) that died in 1977. In five it was considered severe enough to cause significant renal dysfunction; in two of these it was the cause of death. The basic lesion was a proliferation of mesangial cells and deposition of mesangial matrix in the mesangial stalk, resulting in various degrees of stalk expansion and increased lobulation of the glomerular tuft. Preliminary immunofluorescence and ultrastructural studies suggests the pathogenesis of the lesion may involve deposition of antigen-IgM immune complexes in the mesangial region.