ANCA-Positive Pauci-Immune rapidly progressive glomerulonephritis and the nephrotic syndrome

Atypical presentation of a rare disease can pose diagnostic difficulties. Renal vasculitis cha­racteristically presents with acute crescentic glomerulonephritis and the nephrotic syndrome is often manifested in severe cases. In the pa­tient we are reporting in this paper, the sole presentation of vasculitis was the nephrotic syndrome, which has not been reported pre­viously, to our best knowledge. This presen­tation raises the possibility of whether the di­sease, at its outset, was a primary glomerulo­nephritis (GN) that later evolved to systemic vasculitis in the form of ANCA-positive nec­rotizing crescentic glomerulonephritis (NCGN), with its clinical corollary of rapidly progressive renal failure (RPRF). Thus, did our patient have an unusual presentation of vasculitis, or were there two distinct disease entities. We attempt at emphasizing the significant clinical, histopa­thological and electron microscopic (EM) fin­dings of each possibility, in order to hypo­thesize the most probable diagnosis.