Diagnose This! (January 22, 2018)

What is your diagnosis?

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The photomicrograph shows a collapsing glomerular lesion on SMMT stain. Collapsing glomerulopathy is sometimes described as a type of focal segmental glomerulosclerosis, however it is best thought of as its own entity as it has many potential etiologies/associations. Chief among these is its strong association with the presence of underlying APOL1 gene risk variants in African Americans and those of West African descent.  Additionally, it has been reported in association with viral illnesses such as HIV, HCV, HTLV-1, and parvovirus B19 and in association with autoimmune disease, hematologic neoplasia, and drugs such as pamidronate and interferon.