A Case of Progressive Tubulo-Interstitial Nephritis due to Culture-negative Renal Tuberculosis.

This report describes a woman with progressive renal failure without proteinuria, urinary obstruction or overt systemic disease. The progressive renal disease without pelvicalyceal deformities in the left kidney was not consistent with the vesicoureteric reflux nephropathy. A needle biopsy of the left kidney showed interstitial caseating granulomata. The patient did not have clinical, radiological or urine culture evidence of renal tuberculosis. She improved after treatment with antituberculous therapy. This case report demonstrates the value of kidney biopsy in establishing the diagnosis of such common and treatable disease even if clinically silent and urine culture negative.