Aneurysms of the renal arteries associated with segmental arterial mediolysis in a case of polyarteritis nodosa

Abstract

This is the first report of segmental arterial mediolysis (SAM) accompanied with polyarteritis nodosa (PN), and manifesting aneurysms of the renal arteries. A 73-year-old woman was admitted to hospital because of a high fever. Laboratory tests showed leukocytosis with increased CRP level in the serum. Myeloperoxidase-anti-neutrophil cytoplasmic antibody (MPO-ANCA) and proteinase 3 (PR3)-ANCA were negative. There were no signs indicating infection or malignancy. After admission renal function rapidly deteriorated. Treatment was then started with daily oral prednisolone and hemodialysis. On the 40th day of hospitalization the patient suddenly became comatose. Cranial CT showed a subarachnoid hemorrhage. The patient died and an autopsy was performed. The pathological findings showed necrotizing vasculitis of the small arteries in various organs, but not associated with that of arterioles or renal glomerular lesions, indicating PN. Unexpectedly, the segmental arteries of the bilateral kidneys showed vascular lesions of dissecting aneurysms, indicating SAM. This case indicates that SAM is one of the causes of aneurysms in PN and is clinically important when the clinical course of PN patients rapidly advances.

Segmental arterial mediolysis (SAM): Systematic review and analysis of 143 cases

“…Reported methods for diagnosing SAM. (A) A total of 121 cases were identified from the 66 case reports 4,5,8–10,13,22–81 with unique diagnostic strategies. For publications detailing multiple patients, a case was counted as unique if the diagnostic strategy was specifically based on that patient’s presentation and was considered redundant and only recorded once if the same strategy was applied to multiple patients in the report.…”

Segmental Arterial Mediolysis with Preceding Symptoms Resembling Viral Infection Hampers the Differentiation from Polyarteritis Nodosa

“…Pathologically, SAM results from vacuolar degeneration of arterial smooth muscle, leading to mediolysis and hemorrhaging at the adventitia-medial junction and within the media. Transmural mediolysis leads to the formation of arterial wall gaps in medial dissection, and then aneurysmal and stenotic formation occurs (8, 9).…”

Unexpected intraabdominal hemorrhage due to segmental arterial mediolysis following subarachnoid hemorrhage: A case of ruptured intracranial and intraabdominal aneurysms

“…Ten cases of coexisting SAH and visceral aneurysm have been reported. [ 2 3 4 6 8 12 14 20 21 22 ] Table 1 presents the characteristics of the patients, of whom only six also suffered from abdominal bleeding caused by rupture of visceral aneurysm, as in our patient. [ 3 4 6 14 21 22 ] Only three of the six cases were diagnosed as abdominal SAM, [ 4 14 22 ] but all resembled our case in clinical features, that is, the abdominal bleeding occurred within several days in most cases to 1 month in one case of the onset of SAH, and the intracranial aneurysms were not all dissections but also included saccular types.…”