Renal itch

Renal itch is localized or generalized itch, affecting patients with chroni c renal failure, where there is no primary skin disease and no systemic or psychological dysfunction that might cause pruritus. It does not result fro m raised serum urea levels. The prevalence of renal itch has increased with the growing population in chronic renal failure and is a considerable caus e of morbidity. The prevalence of itch increases with deteriorating renal f unction but does not improve significantly with dialysis. The pruritus is i ndependent of duration of dialysis or cause of renal failure. The aetiology of renal itch is unclear. There is little evidence of a major role for his tamine and antihistamines are rarely beneficial. Hyperparathyroidism, abnor mal cutaneous innervation and endogenous opioids have been postulated as co ntributory factors. Treatment of renal itch is difficult. Naltrexone, oral activated charcoal, UVB phototherapy and ondansetron have been shown to be effective. Topical capsaicin may be of benefit in patients with localized p ruritus, The definitive treatment for renal itch remains renal transplantat ion.