Abstract
Serum type IV collagen levels were measured in 328 healthy subjects and 186 diabetics using a newly developed sandwich enzyme immunoassay of whom the values are believed to reflect fibrogenetic activity. Levels in diabetics without diabetic complications were significantly (p<0.01) higher than in healthy subjects. The levels increased in proportion to the duration and degree of diabetic nephropathy, retinopathy and neuropathy. Levels in diabetics with abnormal elevations of blood urea nitrogen, serum creatinine and β2-microglobulin were significantly (p<0.01) higher than in diabetics with normal values for these indices. In contrast, levels were not significantly different in groups which did or did not exhibit abnormal increments in urinary β2-microglobulin and β-N-acetyl-D-glucosaminidase. It appears that the serum level of type IV collagen is a useful biochemical marker for monitoring diabetic complications which mainly involve abnormal metabolism of the basement membrane, and that it is closely correlated with renal glomerular filtration rate.
