title: [A case report of segmental arterial mediolysis].
abstract: We report a case of 58-year-old woman with a ruptured dissecting aneurysm of the middle colic artery (MCA). Her initial manifestation was sudden and severe right-sided abdominal pain, followed by hemorrhagic shock and acute anemia. Abdominal CT showed a right retroperitoneal hemorrhage. Emergency catheter angiography and therapeutic coil embolization of the middle colic artery were performed and micro aneurysms were enhanced in the jejunal branch. Immunological tests showed nothing abnormal. Follow-up angiography after 3 months showed that the micro aneurysms had disappeared. The patient was diagnosed as having segmental arterial mediolysis (SAM), because no definitive evidence of atherosclerosis and polyarteritis nodosa were observed. SAM is a rare disease of unknown etiology. The arterial lesions developing in elderly patients are characterized by segmental lysis of the abdominal splanchnic arteries resulting in aneurysms, and acute bleeding in a skip pattern. Multiple aneurysms and abdominal pain due to the rupture of these lesions in SAM resemble the clinical findings in polyarteritis nodosa. Differential diagnosis of the two diseases is important because steroid therapy is not beneficial for SAM.
authors.affiliation: Division of Rheumatic Diseases, International Medical Center of Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Masato
authors.initials: M
authors.lastname: Moriguchi
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Suminaga
authors.forename: Chiaki
authors.initials: C
authors.lastname: Nagashio
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Kano
authors.forename: Akitake
authors.initials: A
authors.lastname: Suzuki
authors.forename: Jyunwa
authors.initials: J
authors.lastname: Kunimatsu
authors.forename: Rin
authors.initials: R
authors.lastname: Asao
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yamashita
authors.forename: Kenji
authors.initials: K
authors.lastname: Itoh
authors.forename: Akio
authors.initials: A
authors.lastname: Mimori
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001158:Arteries / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013152:Splanchnic Circulation; D014652:Vascular Diseases / Q000473:pathology*