Podocyte fusion observed on electron microscopy is typically associated with which condition?

Podocyte fusion observed on electron microscopy is a hallmark feature of minimal change disease. This condition is characterized by significant alterations in podocyte structure, leading to a decrease in their number and abnormal foot processes that result in effacement or fusion. This structural change is key to the pathophysiology of minimal change disease and is primarily responsible for the nephrotic syndrome seen in affected individuals.

In minimal change disease, these changes at the glomerular filtration barrier lead to increased permeability to proteins, resulting in substantial proteinuria. The podocyte fusion observed under electron microscopy provides direct evidence of the damage to the filtration barrier that underlies the clinical manifestations of the disease. This feature helps distinguish minimal change disease from other forms of glomerular disease, which may present with different morphological findings.

For instance, focal segmental glomerulosclerosis is characterized by the presence of scarring or sclerosis in certain segments of glomeruli and may show different alterations in podocyte architecture. Membranoproliferative glomerulonephritis typically presents with mesangial proliferation and a thickened glomerular capillary wall rather than podocyte fusion. Diabetic nephropathy is marked by changes related to diabetic microangiopathy, including hyaline arteriosclerosis