INTERTUBULAR CAPILLARY CHANGES IN THE CORTEX AND MEDULLA OF TRANSPLANTED KIDNEYS AND THEIR RELATIONSHIP WITH TRANSPLANT GLOMERULOPATHY - ANULTRASTRUCTURAL-STUDY OF 12 TRANSPLANTECTOMIES
G. Mazzucco et al., INTERTUBULAR CAPILLARY CHANGES IN THE CORTEX AND MEDULLA OF TRANSPLANTED KIDNEYS AND THEIR RELATIONSHIP WITH TRANSPLANT GLOMERULOPATHY - ANULTRASTRUCTURAL-STUDY OF 12 TRANSPLANTECTOMIES, Ultrastructural pathology, 18(6), 1994, pp. 533-537
Twelve kidney allografts removed 3 to 98 months (mean, 44.8 months) af
ter transplantation were investigated. The presence and severity of in
tertubular capillary changes, which were characterized by splitting an
d multilayering of the basement membrane, were carefully noted. These
changes were graded as mild, moderate, and severe according to the num
ber of basement membrane layers. They were found in both cortical and
medullary capillaries in all but one kidney and were always associated
with transplant glomerulopathy. Ultrastructural changes observed in t
he glomeruli and capillaries were similar, suggesting that they share
the same pathogenetic mechanisms, probably connected to immune-mediate
d endothelial cell damage. Although glomeruli can be absent in small b
iopsy specimens, intertubular capillaries are easily detectable. Becau
se capillary changes can be considered a marker of transplant glomerul
opathy, which is known to have ominous prognostic significance, the id
entification of such changes acquires clinical relevance. Electron mic
roscopic investigation is therefore strongly advisable whenever a rena
l biopsy is performed to identify transplant glomerulopathy.