Repeat renal biopsy in a girl with tubulointerstitial nephritis and uveitis syndrome

A Japanese girl aged 8 years who presented with a 2-month history of uveiti s subsequently developed tubulointerstitial nephritis. A percutaneous renal biopsy revealed massive interstitial mononuclear cell infiltrates consisti ng of CD4-positive T cells. Despite administration of topical corticosteroi ds, the ocular symptoms persisted. Systemic corticosteroid therapy dramatic ally reduced the ocular symptoms and urinary beta (2)-microglobulin (beta 2 MG) concentration. However, reducing the prednisolone dosage induced recurr ence of uveitis associated with increased levels of urinary beta 2MG. The C D4-positive T cell infiltration persisted in the second renal biopsy perfor med 6 months after the first renal biopsy. These observations suggest that the interstitial cell infiltration persists for a relatively long time in a proportion of patients with tubulointerstitial nephritis and uveitis syndr ome (TINU). Although the renal outcome of TINU has been reported to be favo rable, prolonged interstitial cell infiltration may affect long-term renal outcome. Selected patients with TINU should be followed with close observat ion.