Diagnose This (August 21, 2017)

What is this finding and what does it mean?

​   ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​   ​ ​   ​ ​   ​ ​     ​

This electron photomicrograph shows peritubular capillary multilayering consisting of multiple, interrupted, additional layers of basement membrane around a peritubular capillary. This is a somewhat uncommon finding seen in patients with chronic antibody mediated rejection. It is often accompanied by more common findings like microcirculation inflammation (peritubular capillaritis and glomerulitis), transplant glomerulopathy, transplant arteriopathy and positive C4d staining of the peritubular capillaries.