New insights into the pathophysiology and treatment of chronic itch in patients with end‐stage renal disease, chronic liver disease, and lymphoma

Abstract

Chronic itch associated with systemic diseases continues to be one of the most bothersome dermatological symptoms accompanying end-stage renal disease (ESRD), chronic liver diseases, and lymphoma. The International Forum for the Study of Itch has recently issued a consensus paper on different types of chronic pruritus, including pruritus in systemic diseases that can present with or without secondary skin changes.1Various types of itch have been described based on the origin of the itch, which could be skin-related, neuropathic, systemic, or psychogenic.2 At any given time patients with these systemic diseases may have more than one origin, for example, patients with end-stage renal disease (ESRD) could have neuropathic itch due to nerve fibers damage, as well as itch associated with skin inflammation such as perforating folliculitis. Itch adversely affects quality of life of patients, leading to sleep deprivation and depression that further augment itch. Chronic itch associated with systemic diseases range from mild to intractable, which is defined as a chronic itch state in which the cause cannot be removed or treated, and no relief or cure has been found in the generally accepted course of medical practice.3 In the last decade, there are significant advances in our understanding of specific itch neuronal pathways, mediators and relevant receptors, opening the field for development of new antipruritic strategies. The purpose of this review is to highlight the new findings related to the pathophysiological mechanisms and the treatment of itch associated with the most common systemic diseases including ESRD, chronic liver disease and lymphoma.