Intertubular capillary changes in kidney allografts: an ultrastructural study in patients with transplant glomerulopathy.

Fifteen kidney allograft specimens from 14 patients with transplant glomerulopathy were investigated by electron microscopy. Intertubular capillaries of all patients showed splitting and multilayering of the basement membranes, a change recalling that observed in the glomerular basement membranes in transplant glomerulopathy. Although the severity of the lesions varied from case to case, it was, to a certain extent, constant in each specimen and correlated well with the severity of the glomerular basement membrane changes in the same patient. The similarity of the two lesions suggests a possible common pathogenetic mechanism. The constant finding of intertubular capillary splitting and multilayering in patients with transplant glomerulopathy leads to the suspicion of this condition when such changes are found in kidney samples in which glomeruli are lacking. Therefore electron microscopy could achieve a specific diagnostic relevance in this field of nephropathology.