Intraglomerular tubular epithelial cells. A marker of glomerular hematuria.

The occurrence of intraglomerular tubular epithelial cells (ITEC) was investigated in 202 consecutive renal biopsy specimens and were present in 111 (55%). Minimal, focal, or diffuse glomerular diseases were all represented. Of the patients with ITEC 110 (99%) had gross or microscopic hematuria, either alone or associated with proteinuria; however, ITEC were found only in one of 79 proteinuric patients with no documented hematuria. Intraglomerular tubular epithelial cells did not occur in four patients with drug-induced interstitial nephritis and microscopic hematuria, or in 11 normal controls. The pathogenesis of ITEC is not known, but our data indicate that the phenomenon is almost constantly found in association with glomerular hematuria. Identification of ITEC, therefore, should help to confirm the glomerular origin of hematuria when histologic alterations are minimal.