Bilateral renal cortical calcification, suspicious for cortical nephrocalcinosis.

Histopathology:

Microscopic examination reveals one core of renal corticomedullary tissue. Seventeen glomeruli are detected; one of which is obsolescent. The tufts show focal ischemic changes and thickening of the glomerular basement membrane with focal double contouring pattern. Few glomeruli show a bloodless pattern and some glomeruli contain thrombi. Single glomerulus shows segmental sclerosis and another one is compressed by a fibrocellular crescent. The tubules show marked hydropic degeneration with patchy injury, foci of tubulitis, and many foci of microcalcification, as well as hyaline and red cell casts, are seen.  The interstitium shows edema, moderate lymphocyte infiltration, and patchy mild fibrosis.  The arteries are normal. Some arterioles show mucoid intimal thickening and few arterioles show extravasated, fragmented RBCs in the wall. JGAs are normal.

Diagnosis:  The picture is compatible with healing stage of thrombotic microangiopathy with secondary focal segmental glomerulosclerosis.