# Chronic Kidney Disease-Associated Pruritus in Hemodialysis: Unraveling Mechanisms and Emerging Therapeutic Targets—A Systematic Review

## TL;DR

This review explores the causes and treatments for itching in hemodialysis patients, revealing it as a complex condition with multiple contributing factors.

## Contribution

The paper systematically integrates recent findings to establish CKD-associated pruritus as a multidimensional disorder with novel therapeutic targets.

## Key findings

- CKD-aP is linked to gut dysbiosis, immune activation, and neural sensitization.
- κ-opioid receptor agonists show promise as targeted therapies for CKD-aP.
- Standardized assessment tools like UP-Dial and Skindex-10 are recommended for measuring disease burden.

## Abstract

This systematic review examines chronic kidney disease-associated pruritus (CKD-aP) as a complex clinical manifestation in patients undergoing hemodialysis. Traditionally considered a secondary symptom of end-stage renal disease, emerging evidence now positions CKD-aP as a multidimensional disorder with substantial pathogenic influence on patient outcomes. Using the PRISMA 2020 methodology, we critically evaluated 54 peer-reviewed studies published between 2020 and 2025. Our synthesis highlights a convergence of five mechanistic frameworks underpinning CKD-aP: elevated levels of uremic toxins originating from gut microbial dysbiosis, immune activation driven by IL-31 and other pro-inflammatory cytokines, heightened peripheral and central neural sensitization, dysregulation of endogenous opioid receptor pathways favoring μ-receptor activation, and xerosis-related epidermal barrier dysfunction. These mechanisms contribute to a systemic cycle of microinflammation, pruritogenic signaling, and neural hyperexcitability. We also identified and compared validated assessment tools—including the NRS, VAS, Skindex-10, and the UP-Dial scale—that facilitate standardized quantification of disease burden. While available treatments such as gabapentinoids and phototherapy offer partial relief, targeted therapies—including κ-opioid receptor agonists—represent a major advancement, although long-term effectiveness and accessibility remain under investigation. Growing scientific consensus establishes CKD-aP as a priority therapeutic target in hemodialysis care, underscoring the need for integrated, mechanism-based management strategies to improve quality of life and clinical outcomes. This work represents a narrative systematic review, integrating evidence from mechanistic, translational, and clinical studies to critically examine the biological pathways underlying CKD-associated pruritus.