Etiological Association of Pruritus in End Stage Renal Disease Patients on Maintenance Hemodialysis

Author(s): Towfik Parvez, Rana Mokarrom Hossain, S M Remin Rafi, S M Shamsuzzaman, Md. Bedar Uddin, Shoriful Islam

Background: Chronic kidney disease–associated pruritus (CKD-aP) is a common, troubling and, in some cases, debilitating problem for patients with CKD and end-stage renal disease (ESRD). Despite a prevalence rate of approximately 20% in CKD and 40% in ESRD and a clear association with poorer psychosocial and medical outcomes, this condition is often underreported by patients and overlooked by healthcare providers. This is likely due to uncertainty regarding its pathogenesis and treatment. Most commonly, CKD-aP is attributed to toxin build-up, peripheral neuropathy, immune system dysregulation, or opioid dysregulation. The exact pathogenesis remains largely elusive, which hampers the definite treatment protocol. Studies have shown changes in the immunochemical milieu of the skin in patients with CKD-aP, with several inciting stimuli identified. However, other unrecognized factors are likely to be involved. Aim of the study: To find out the etiological association of pruritus in ESRD patients on maintenance hemodialysis. Methods: This prospective observational study was carried out in the Department of Nephrology BSMMU and ShSMCH, Dhaka, Bangladesh. A total of 60 patients with CKD Stage 5 on MHD were included in this study. CKD stage 5 on MHD with pruritus and without pruritus were considered group I and group II. Patients aged above 18 years and undergoing hemodialysis for at least 3 months were enrolled in this study. Result: This study showed mean age was 47.24±15.63 years (range: 18-69) in Group I and 43.14±15.07 years (range: 18-73) in Group II, with the majority (76.5%) of the population being female in Group I. Glomerulonephritis (GN) was the predominant aetiology and hypertension (HTN) was a prominent comorbidity in both groups. Mild pruritus was most prevalent (47.1%) in a pruritic group of patients. Among pruritic patients, more than half (52.9%) patients had generalized pruritus. Almost three-fourths (70.6%) of patients rarely experienced sleep disturbance. The IL-31 exhibited a marked difference, with Group I showing a significantly higher mean of 128.23±77.34 xiii compared to Group II's mean of 60.52±36.25 (P0.05) with the severity of pruritus. Twice weekly treated patients (Mean±SD was 107.9±68.9) were more prone to develop pruritus than those getting thrice weekly with no significant difference in terms of IL-31, with the frequency of HD per week. Laboratory parameters had no significant differences between the two groups in terms of Hb, WBC, Circulatory eosinophil count, IgE, S. Ca, S. P04, Ca *P04 product and iPTH. Receiver-operator characteristic (ROC) was constructed by using IL-31, which cut value 87.7, with 70.6% sensitivity and 81.4% specificity. Conclusion: In this study, there was a significant difference in the IL-31 level between pruritic and nonpruritic patients. IL-31 levels didn't directly correlate with the severity of pruritus in ESRD patients on maintenance hemodialysis. Twice-weekly hemodialysis patients were more prone to develop pruritus than thrice-weekly treated patients. Besides, there was no significant difference in terms of IL-31 level with the frequency of HD.