Chronic Pruritus and Connective Tissue Disorders: Review, Gaps, and Future Directions.

Chronic itch is a common skin manifestation in many connective tissue diseases. However, the cause of chronic itch in these diseases is still not fully understood. The complex, and in some cases incomplete understanding of, pathogenesis in each condition makes it difficult to target specific mediators of chronic itch. It is important to better understand the pathophysiology of chronic itch in these conditions, as this information might provide a fuller understanding of the pathogenesis of the diseases in general and lead to the development of more specific treatments for connective tissue diseases in patients with chronic itch. We present a review of the literature on what is known about the prevalence, possible pathophysiology, and effect on quality of life of chronic itch in patients with scleroderma, Sjögren's syndrome, dermatomyositis, systemic lupus erythematosus, cutaneous lupus erythematosus, and mixed connective tissue disease.