Granulomatous Interstitial Nephritis - A Series of Six Cases.

Granulomatous interstitial nephritis is an uncommon variant accounting for about 6% of all tubulointerstitial nephritis. The etiology can be drugs such as antibiotics and nonsteroidal anti-inflammatory drugs and infections such as tuberculosis, sarcoidosis, and fungal infections. Renal biopsy remains the gold standard for establishing the diagnosis. Here, we present a series of six cases of granulomatous interstitial nephritis, of which two cases were associated with lupus nephritis and another two cases with crescentic glomerulonephritis. Focal segmental glomerulosclerosis and mesangiosclerosis with chronic tubulointerstitial nephritis were detected in the rest of the cases. Most of the patients presented with features of nephrotic syndrome. Urine analysis showed albuminuria in all cases. In renal biopsy, interstitial epithelioid cell granuloma was a constant feature along with which there were foci of necrosis and moderate fibrosis in few cases. But none of our cases had any relevant history of prolonged drug intake. Tuberculosis and fungal infections were also ruled out. Thereby in this case series, we subgroup all the cases into two category four cases associated with granulomatous nephritis and two cases with idiopathic granulomatous nephritis.