High Renal Mast Cell Density Is Associated with Poor Prognosis in Patients with Immunoglobulin A Nephropathy

Abstract

Introduction: This observational cohort study evaluated the prognostic value of mast cells in the pathogenesis and progression of IgA nephropathy. Methods: A total of 76 adult IgAN patients were enrolled into this study from Jan 2007 and June 2010. Immunohistochemistry and immunofluorescence were used to identify tryptase-positive mast cells in renal biopsy samples. Patients were classified into Tryptase^high and Tryptase^low groups. Depending on an average of 96-month follow-up, the predictive value of tryptase-positive mast cells in IgAN progression was analyzed. Results: Tryptase-positive mast cells were found frequently in IgAN kidneys while rarely observed in normal kidneys. We also found IgAN patients in Tryptase^high group presented both severe clinical and pathological renal manifestations. Furthermore, Tryptase^high group contained more interstitial macrophages and lymphocytes infiltration than Tryptase^low group. Higher tryptase-positive cells density is associated with poor prognosis in patients with IgAN. Conclusions: High renal mast cells density is associated with severe renal lesions and poor prognosis in patients with Immunoglobulin A nephropathy. High renal mast cells density might be used as a predictor of poor prognosis in patients with IgAN.