title: Superficial hemosiderotic lymphovascular malformation (hobnail hemangioma): a report of six cases.
abstract: Hobnail hemangioma (HH), initially termed targetoid hemosiderotic hemangioma, is a rare, often solitary lesion classically characterized by a central brown or violaceous papulonodule surrounded at times by an ecchymotic halo. This lesion is typically found on the trunk or limbs of children or young to middle-aged adults. Numerous case reports have found HHs to have a reproducible histologic appearance. Although the exact histogenesis of these lesions is unknown, multiple recent immunohistochemical studies suggest a lymphatic origin of these lesions. We present six cases of children with HHs with classic histology but with variability in their clinical appearance. Because the clinical presence of a targetoid halo is inconsistent and the hobnail phenomenon is not specific, we favor the designation of superficial hemosiderotic lymphovascular malformation instead of HH or targetoid hemosiderotic hemangioma as a more unifying term for this rare clinical entity. By eliminating confounding terminologies (in this case, incorporation of "hemangioma" in the name of this entity), we also hope to encourage a swifter change in practice to move away from erroneous diagnostic considerations.
authors.affiliation: Department of Dermatology, Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Joel C
authors.initials: JC
authors.lastname: Joyce
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Keith
authors.forename: Sara
authors.initials: S
authors.lastname: Szabo
authors.forename: Kristen E
authors.initials: KE
authors.lastname: Holland
mesh_terms: D000293:Adolescent; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D004438:Ecchymosis / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006391:Hemangioma / Q000378:metabolism / Q000473:pathology*; D006485:Hemosiderin / Q000378:metabolism; D006801:Humans; D008297:Male; D012867:Skin / Q000378:metabolism / Q000473:pathology*; D012878:Skin Neoplasms / Q000378:metabolism / Q000473:pathology*
chemical_list: D006485:Hemosiderin