Endocrine causes include thyrotoxicosis and, less often, diabetes. The pruritus may precede the diagnosis of lymphoma. Symptoms of burning and intense itching may occur on a localized skin area, frequently the lower part of the legs. A less intense but more generalized pruritus may be observed with other lymphomas or leukemias. Cancer of the stomach, the pancreas, the lung, the colon, the breast, the prostate, or another primary site may sometimes be associated with the presence of generalized pruritus.
Treatment includes elimination of the systemic cause, when possible.
Cholestyramine, an ion exchange resin, has been used to lower the bile salts in patients who have pruritus caused by cholestatic liver disease. Supportive measures include the use of emollients and soap substitutes and decreased bathing to counteract skin dryness or xerosis that may aggravate itching. Systemic antipruritics of different pharmacological classes may also be tried. Ultraviolet phototherapy with UVB radiation is effective in the control of pruritus related to renal disease. Seventeen patients who were rated as having severe pruritus were randomly treated with either UVA or UVB phototherapy, which was administered three times weekly before hemodialysis.