Department of Family and Community Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston Matasha.L.Russell@uth.tmc.edu
The authors reported no potential conflict of interest relevant to this article.
In this review, we focus on the work-up and management of 3 of those categories: systemic, neurologic, and psychogenic causes of pruritus.
Systemic causes
Research has shown that 14% to 24% of patients who seek the care of a dermatologist for chronic itch without skin lesions have a systemic illness.8
Renal disease. Approximately 40% of patients with end-stage renal disease who are on hemodialysis or peritoneal dialysis have uremic pruritus.2 The itch is mostly generalized but can be pronounced on the back. For most patients, the itch is worse at night, causing a major impact on quality of life.6
Liver disease. In hepatic disease, there is often impairment in the secretion of bile, which can lead to cholestatic pruritus.2 This condition commonly affects the hands and feet first; later, it becomes generalized.2 Cholestatic pruritus can be elicited by tight-fitting clothing. Relief is not achieved by scratching.9 This type of itch effects 70% of patients with primary biliary cirrhosis and 15% of patients with hepatitis C infection.9
Hematologic disorders. Pruritus is a hallmark symptom of polycythemia rubra vera. Almost 50% of patients with this disorder report pruritus that occurs after exposure to water9; aquagenic pruritus can precede the formal diagnosis of polycythemia rubra vera by years.2 It has been speculated that platelet aggregation in this disorder leads to release of serotonin and histamine, which, in turn, causes itch.9
