Callitrichid IgM-nephropathy--an old age-related disease?

In 185 callitrichids of exactly known age the occurrence of mesangial IgM-deposits and mesangial lesions has been evaluated. Mesangial IgM-deposits were observed already in early infancy, at that time without morphological sequelae. Signs of mesangial lesions were first observed in a 3-months old animal and with a sharp increase of mesangial lesions between 4 months and one year of age all suggesting an onset early in life. In contrast in higher age groups a significant number of animals suffered from glomerulosclerosis without IgM deposits, which could be interpreted as 'old age nephropathy' independent from IgM-nephropathy.