By Gary M. White, MD
Intralymphatic histiocytosis (IH) is a rare, benign condition characterized by the accumulation of macrophages within dilated lymphatic vessels. It usually is associated with rheumatoid arthritis there are reports of this condition in association with breast, Merkel cell, and colon carcinomas; 4 cases were reported overlying surgical scars after hip and knee joint replacements.
It is characterized by nonspecific, poorly demarcated, irregular erythematous patches, but the clinical features are variable and livedo, indurated plaques, nodules, vesicles, and papules have all been described. A 73 year old man with diffuse blanching violaceous discoloration of the entire trunk has been described [Br J Dermatol 2017;177;323].
An 85-year-old man with a large, poorly demarcated, pink-to-violaceous, livedoid plaque on the right anterior chest, shoulder, and upper arm for 2 to 3 years. From JAAD December 2013;Volume 69, Issue 6, Pages e314–e315
AAD May 2014 Volume 70, Issue 5, Pages 927–933