Tubulointerstitial Nephritis and Uveitis Syndrome Associated with Renal Tryptaseand Chymase-positive Mast Cell Infiltration

We report the clinical course and immunohistochemical analysis of a patient who presented with tubulointerstitial nephritis and uveitis syndrome (TINU syndrome). The patient, a 40-year-old woman, was referred to our hospital with general fatigue and a slight fever from another hospital. Mast cells are closely related to the development of renal interstitial fibrosis in patients with glomerulonephritis. To determine the role of mast cells in renal interstitial injury in TINU patients, we performed immunohistochemical studies on renal biopsy specimens using anti-human tryptase and anti-human chymase antibodies specific for mast cells. Double immunostaining of tryptase and chymase was also performed in renal tissues. In double immunofluorescence, cells with both chymase and tryptase (MCtc) were marked in the regions of interstitial fibrosis in this patient. It appears that mast cells are one of the constitutive cells of interstitial fibrosis in patients with TINU syndrome.