Serum mast cell tryptase in patients with renal failure and its relation to severity of pruritus

Abstract

Objective The aim of this study was to evaluate the possible role of mast cell tryptase (MCT) enzyme in the pathogenesis of uremic pruritus by measuring its level in the serum of patients with chronic kidney disease (CKD) with pruritus and to correlate its level with the severity of pruritus. Background The pathogenesis of pruritus in renal disease is not yet understood. Evidence suggests that mast cells play a role, as the number of dermal mast cells is increased in patients on hemodialysis. Patients and methods The present study was conducted as a prospective case–control study that included 60 patients with CKD and 20 healthy participants who had neither CKD nor pruritus and served as controls. All cases were selected from the Outpatient Clinic and Dialysis Unit of Nephrology Department, Menoufia University Hospitals, and Aga General Hospital, spanning the period from February 2017 to July 2017. Patients with CKD were subdivided into three groups according to the stage of kidney disease as follows: group 1 included 20 patients with stage 3 (CKD), group 2 included 20 patients with stage 4 (CKD), group 3 included 20 patients with stage 5 (CKD), known as end-stage renal disease, who were on hemodialysis. Each participant underwent full general and dermatologic examination followed by measurement of serum MCT enzyme by enzyme-linked immunosorbent assay. Degree of pruritus was measured by 5D score. Results Serum MCT levels were above 11.4 ng/ml (95th percentile) in patients with CKD. The intensity of pruritus correlated significantly (P = 0.001) with the tryptase levels. Conclusion Mast cells or even tryptase itself may be involved in the pathogenesis of pruritus in patients with CKD.