Someone asked: how do you manage de novo collapsing glomerulonephritis in a kidney transplant recipient?
Short answer: we don’t know!
It is safe to say we are in an evidence free zone here. This condition is certainly rare – limited to case reports or small case series. The first thing to say is that collapsing GN is a pattern of injury that can be seen in background of many glomerular disease, and results from more than one pathogenetic mechanism. It, however, confers a uniformly poor prognosis to all of them.
Once recurrence of glonerular disease has been ruled out, we should consider what could be the possible cause because that will have a bearing on management. Postulated mechanisms include Parvovirus B19 infection (treatment: reduction of immunosuppression and IVIG), microvascular injury secondary to sirolimus, or drug induced TMA (take off the offending drug, ?try plasmapheresis), or a situation where the allograft comes from a donor harboring mutations in the APOL1 gene, which predisposes to collapsing GN in the face of a second hit (such as infection – CMV, bacterial, etc). Not much you can do in the last case.
Given that microvascular injury can cause collapse, one can wonder whether antibody-mediated endothelial injury can also lead to this presentation. Indeed some of the initial descriptions were described in association with “chronic rejection”.
Clearly, an entity looking for someone to latch on to in terms of developing a research career…