Significance of TARC as an itch index in hemodialysis patients

Among patients undergoing chronic maintenance hemodialysis, some complain of pruritus despite oral treatment with histamine H1 receptor antagonists ; these patients are called pruritus hemodialysis patients resistant to existing treatment. The intensity of pruritus was evaluated in 64 hemodialysis patients at our hospital using the Hearing Analogue Scale (HAS) devised at our hospital, as well as by measuring the serum levels of thymus and activation-regulated chemokine (TARC ; a type of chemokine). The HAS score, which may reflect the intensity of generalized pruritus, correlated well with the serum TARC level, suggesting that the serum TARC level can be used as a substitute for the HAS score. Subsequently, nalfurafine hydrochloride (nalfurafine) was orally administered at a dose of 2.5μg to 2 pruritus hemodialysis patients. Both the HAS score and the serum TARC level decreased after treatment, and the severity of pruritus also decreased. Thus, both parameters are useful indicators of the severity of pruritus in hemodialysis patients.