Extramedullary Hematopoiesis An Unusual Finding in Angiolymphoid Hyperplasia With EosinophiliaJohnson, Nathan M. MD; Thomas, Raj J. BS; Grider, Douglas J. MDThe American Journal of Dermatopathology: September 2019 - Volume 41 - Issue 9 - p 680–683 doi: 10.1097/DAD.0000000000001407 Extraordinary Case Report Buy Abstract Author InformationAuthors Article MetricsMetrics Abstract: Extramedullary hematopoiesis is the process of blood cell synthesis occurring outside the medulla of the bone marrow. During fetal development, extramedullary hematopoiesis is considered physiological; however, it is considered pathologic when occurring outside the neonatal period. Angiolymphoid hyperplasia with eosinophilia (ALHE) describes a lesion characterized histologically by plump endothelial cells associated with a mixed inflammatory infiltrate of lymphocytes, plasma cells, mast cells, and eosinophils. This report describes an adolescent boy with an isolated preauricular facial lesion. After excision, histopathology confirmed a diagnosis of ALHE with the additional finding of trilineage extramedullary hematopoiesis. To the authors' knowledge, this is the first reported case of extramedullary hematopoiesis in ALHE. Department of Internal Medicine, Dermatology Division, Carilion Clinic and Virginia Tech Carilion School of Medicine, Roanoke, VA; and Edward Via College of Osteopathic Medicine, Blacksburg, VA. Correspondence: Douglas J. Grider, MD, E-mail: DJGrider@carilionclinic.org The authors declare no conflicts of interest. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.