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.