Reticular Inclusions in HIVAN

The histology of HIVAN (HIV-Associated Nephropathy), at the light microscopy level, is indistinguishable from that of collapsing FSGS: the glomerular capillary loops are collapsed. Furthermore, both entities demonstrate foot process effacement (as in all forms of nephrotic syndrome) on electron microscopy.

However, one distinguishing feature between HIVAN and collapsing FSGS is the presence of tubular reticular inclusions (see photo) within endothelial cells commonly seen in HIVAN, but not collapsing FSGS. This finding is not 100% sensitive for HIVAN, nor is it 100% specific: the current thought is that these inclusions form in response to high circulating interferon-alpha levels, which may also be present in inflammatory conditions such as lupus.