Segmental Arterial Mediolysis: A Case of Mistaken Hemorrhagic Pancreatitis and Review of the Literature

  • Jennifer L Horsley-Silva Department of Internal Medicine, Mayo Clinic. Jacksonville, FL, USA
  • Saowanee Ngamruenphong Department of Gastroeterology, Mayo Clinic. Jacksonville, FL, USA
  • Gregory T Frey Department of Radiology, Mayo Clinic. Jacksonville, FL, USA
  • Ricardo Paz-Fumagalli Department of Radiology, Mayo Clinic. Jacksonville, FL, USA
  • Michele D Lewis Department of Gastroeterology, Mayo Clinic. Jacksonville, FL, USA
Keywords: Abdominal Pain, Aneurysm, Arteritis, Dissection, Hemorrhage, Pancreatitis


Context Segmental arterial mediolysis is an uncommon, non-atherosclerotic, non-inflammatory arteriopathy that involves areas of dissecting aneurysms and strictures that are caused by outer media lysis of the arterial wall from areas of medial necrosis of uncertain pathogenesis. It has a predilection for splanchnic arteries and often presents as abdominal pain or hemorrhage in late middle-aged and elderly patients. Diagnosis can be established by computed tomography angiography, magnetic resonance angiography, or angiogram by visualizing typical abnormalities, in addition to excluding other vasculitides. Histological confirmation is the gold standard but is not easily accessible and, as such, is not frequently performed. Case report Here we present an updated review of the literature and a case of segmental arterial mediolysis that presented with spontaneous intra-abdominal bleeding near the pancreas that was originally misdiagnosed as hemorrhagic pancreatitis. Conclusion Diagnosis is important because immunosuppressants for vasculitis can worsen the arteriopathy. Segmental arterial mediolysis can be self-limiting without treatment or may require urgent surgical or endovascular therapy for bleeding and carries a 50% mortality rate. Therefore, it should be included in the differential of causes of abdominal pain as well as in cases of unexplained abdominal hemorrhage.

Image: Vascular irregularity and pseudoaneurysm formation.


Download data is not yet available.


Slavin RE, Gonzalez-Vitale JC. Segmental mediolytic arteritis: A clinical pathologic study. Lab Invest 1976;35:23-29. [PMID 940319]

Michael M, Widmer U, Wildermuth S, Barghorn A, Duewell S, Pfammatter T. Segmental arterial mediolysis: Cta findings at presentation and follow-up. AJR Am J Roentgenol 2006;187:1463-1469. [PMID 17114538]

Basso MC, Flores PC, de Azevedo Marques A, de Souza GL, D'Elboux Guimaraes Brescia M, Campos CR, et al. Bilateral extensive cerebral infarction and mesenteric ischemia associated with segmental arterial mediolysis in two young women. Pathol Int 2005;55:632-638. [PMID 16185293]

Slavin RE. Segmental arterial mediolysis: Course, sequelae, prognosis, and pathologic-radiologic correlation. Cardiovasc Pathol 2009;18:352-360. [PMID 19026575]

Slavin RE, Saeki K, Bhagavan B, Maas AE. Segmental arterial mediolysis: A precursor to fibromuscular dysplasia? Mod Pathol 1995;8:287-294. [PMID 7617656]

Baker-LePain JC, Stone DH, Mattis AN, Nakamura MC, Fye KH. Clinical diagnosis of segmental arterial mediolysis: Differentiation from vasculitis and other mimics. Arthritis Care Res (Hoboken) 2010;62:1655-1660. [PMID 20662047]

Kalva SP, Somarouthu B, Jaff MR, Wicky S. Segmental arterial mediolysis: Clinical and imaging features at presentation and during follow-up. J Vasc Interv Radiol 2011;22:1380-1387. [PMID 21840227]

Matsuda R, Hironaka Y, Takeshima Y, Park YS, Nakase H. Subarachnoid hemorrhage in a case of segmental arterial mediolysis with coexisting intracranial and intraabdominal aneurysms. J Neurosurg 2012;116:948-951. [PMID 22385002]

Ito N, Kuwahara G, Sukehiro Y, Teratani H. Segmental arterial mediolysis accompanied by renal infarction and pancreatic enlargement: A case report. J Med Case Rep 2012;6:307. [PMID 22989228]

Sakano T, Morita K, Imaki M, Ueno H. Segmental arterial mediolysis studied by repeated angiography. Br J Radiol 1997;70:656-658. [PMID 9227264]

Tomonaga T, Eguchi S, Hidaka M, Takatsuki M, Soyama A, Muraoka I, et al. A case of ruptured segmental arterial mediolysis of the hepatic artery: Report of a case. Hepatogastroenterology 2011;58:1912-1914. [PMID 22234060]

Tameo MN, Dougherty MJ, Calligaro KD. Spontaneous dissection with rupture of the superior mesenteric artery from segmental arterial mediolysis. J Vasc Surg 2011;53:1107-1112. [PMID 21276678]

Cooke DL, Meisel KM, Kim WT, Stout CE, Halbach VV, Dowd CF, et al. Serial angiographic appearance of segmental arterial mediolysis manifesting as vertebral, internal mammary and intra-abdominal visceral artery aneurysms in a patient presenting with subarachnoid hemorrhage and review of the literature. J Neurointerv Surg 2012. [PMID 22693248]

Ryan JM, Suhocki PV, Smith TP. Coil embolization of segmental arterial mediolysis of the hepatic artery. J Vasc Interv Radiol 2000;11:865-868. [PMID 10928523]

Gruenwald P. Necrosis in the coronary arteries of newborn infants. Am Heart J 1949; 38:889-97. [PMID 15395920]

Chao CP. Segmental arterial mediolysis. Semin Intervent Radiol 2009;26:224-232. [PMID 21326567]

Joris I, Majno G. Medial changes in arterial spasm induced by l-norepinephrine. Am J Pathol 1981;105:212-222. [PMID 7315949]

Slavin RE, Yaeger MJ. Segmental arterial mediolysis: an iatrogenic vascular disorder induced by ractopamine. Cardiovasc Pathol 2012;21:334-338. [PMID 22036070]

Slavin RE, Inada K. Segmental arterial mediolysis with accompanying venous angiopathy: A clinical pathologic review, report of 3 new cases, and comments on the role of endothelin-1 in its pathogenesis. Int J Surg Pathol 2007;15:121-134. [PMID 17478765]

Slovut DP, Olin JW. Fibromuscular dysplasia. N Engl J Med 2004;350:1862-1871. [PMID 15115832]

Filippone EJ, Foy A, Galanis T, Pokuah M, Newman E, Lallas CD, et al. Segmental arterial mediolysis: Report of 2 cases and review of the literature. Am J Kidney Dis 2011;58:981-987. [PMID 21872379]

Inada K, Maeda M, Ikeda T. Segmental arterial mediolysis: Unrecognized cases culled from cases of ruptured aneurysm of abdominal visceral arteries reported in the japanese literature. Pathol Res Pract 2007;203:771-778. [PMID 17920781]

Obara H, Matsubara K, Inoue M, Nakatsuka S, Kuribayashi S, Kitagawa Y. Successful endovascular treatment of hemosuccus pancreaticus due to splenic artery aneurysm associated with segmental arterial mediolysis. J Vasc Surg 2011;54:1488-1491. [PMID 21715127]

Lie JT. Segmental mediolytic arteritis. Not an arteritis but a variant of arterial fibromuscular dysplasia. Arch Pathol Lab Med 1992;116:238-241. [PMID 1536608]

Vascular irregularity and pseudoaneurysm formation
How to Cite
Horsley-SilvaJ., NgamruenphongS., FreyG., Paz-FumagalliR., & LewisM. (2014). Segmental Arterial Mediolysis: A Case of Mistaken Hemorrhagic Pancreatitis and Review of the Literature. JOP. Journal of the Pancreas, 15(1), 72-77.