Phenotypic Characterization of Kidney Infiltrating Cell Subsets in Idiopathic Acute Interstitial Nephritis Associated with Uveitis: Evidence for a Cell-Mediated Immune Disease

Abstract

The association of acute interstitial nephritis (AIN) and anterior uveitis without determined cause is quite rare. This disease entity is manifested by uveitis which may precede, occur concomitantly with, or follow AIN. Renal involvement is characterized by acute renal failure which is usually associated with a diffuse interstitial infiltration mainly by mononuclear cells. We report here the clinicopathological features in two cases of this association showing a different time course evolution of the renal disease. Repeat kidney biopsy allowed to study in different points of the disease process both the histological picture and the phenotypic characterization (by an immunohistochemical method) of cells infiltrating the renal interstitium. Immunohistochemical analysis of renal tissue revealed that interstitial infiltrate was primarily composed of T lymphocytes (mainly helper-inducer T cells) and monocytes/macrophages. A clear predominance of memory T lymphocytes (CD45RO+) in the interstitial infiltration was found. These cells persisted in the renal interstitium of the patient in whom renal function remained persistently impaired. The cellular profile of immunocompetent cells in renal lesions suggests a major role for cell-mediated immunity in the development of idiopathic AIN associated with uveitis.