2025 Volume 12 Pages 421-426
An anti-neutrophil cytoplasmic antibody-associated vasculitis is a systemic autoimmune disease characterized by small-vessel inflammation, with rare central nervous system manifestations such as subarachnoid hemorrhage. Cerebral artery dissection, a rare but serious condition that can lead to ischemic stroke or subarachnoid hemorrhage, predominantly affects young to middle-aged adults and is less common in elderly patients. We report the case of an 86-year-old male with anti-neutrophil cytoplasmic antibody-associated vasculitis who developed subarachnoid hemorrhage due to a ruptured posterior inferior cerebellar artery aneurysm, suggestive of dissection. Despite diagnostic challenges related to the patient's advanced age, repeated vascular imaging indicated arterial dissection, and parent artery occlusion successfully prevented re-rupture. This case highlights the importance of considering cerebral artery dissection as a potential cause of subarachnoid hemorrhage in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis, even in octogenarians, and underscores the need for comprehensive vascular evaluation to ensure timely diagnosis and management.
Anti-neutrophil cytoplasmic antibody (ANCA) -associated vasculitis (AAV) is a systemic autoimmune disease primarily affecting small vessels in various organs, such as the lungs, kidneys, skin, and peripheral nerves.1,2) Central nervous system involvement is uncommon, occurring in approximately 5%-15% of cases, and includes rare manifestations such as subarachnoid hemorrhage (SAH).3-8)
Cerebral artery dissection (CAD) is a rare but serious vascular condition that can lead to ischemic stroke and SAH. The pathogenesis of CAD may include genetic predispositions, structural weaknesses in the arterial wall, and inflammatory processes such as vasculitis.9) Although CAD is most frequently diagnosed in younger adults (aged 30-50 years), it is relatively rare in the elderly population, particularly in those aged >70 years.10)
In this report, we present a rare case of ruptured posterior inferior cerebellar artery (PICA) dissection in an octogenarian patient with AAV. This case highlights the diagnostic difficulties and therapeutic challenges posed by CAD in elderly patients.
Before writing this report, a written consent form was obtained from the patient.
An 86-year-old man with no significant past medical history was admitted to our hospital for comprehensive evaluation of renal dysfunction. Laboratory investigations revealed positive results for myeloperoxidase-ANCA, leading to the diagnosis of ANCA-associated nephritis. The patient started corticosteroid therapy and erythromycin therapy at the Department of Rheumatology and Collagen Diseases. The patient's initial clinical course was uneventful, and a renal biopsy was planned for further diagnosis.
The patient's subsequent hospital course remained uneventful until he suddenly lost consciousness and was admitted to the Neurosurgery Department. On arrival, the patient was comatose, with a Japan Coma Scale score of 200 and a Glasgow Coma Scale score of 6 (E1V1M4). A non-contrast computed tomography (CT) scan of the head showed thick SAH in the posterior cranial fossa accompanied by acute hydrocephalus (Fig. 1). Magnetic resonance imaging of the head performed 4 years earlier demonstrated the presence of the right vertebral artery (VA) (Fig. 2A). However, at the onset of SAH, contrast-enhanced CT of the head revealed no blood flow in the right VA and no obvious source of SAH (Fig. 2B). Based on these findings, the right VA was presumed to be chronically occluded at that time. Emergency ventricular drainage (VD) for acute hydrocephalus was performed. Following VD, cerebral angiography (CAG) was performed, which showed areas of irregular vessel caliber extending from the right VA to right PICA, but no definite aneurysm formation was observed (Fig. 2C). Angiography of the anterior circulation confirmed the absence of abnormal findings. Repeat angiography of the right VA performed 30 mins later revealed a pseudoaneurysm at the origin of the right PICA (Fig. 3A and B). The pseudoaneurysm was identified as the most probable cause of the SAH. Furthermore, the rapid progression of vascular changes from the right VA to the right PICA was unexpected, which led us to consider a diagnosis of CAD, despite the advanced age of the patient. Considering the patient's advanced age, critical condition, and the rapid progression of vascular changes observed over a short period, prompt hemostatic intervention was deemed essential. Therefore, parent artery occlusion was performed at the origin of the dominant PICA without revascularization, with the primary aim of preserving the patient's life. Although dissecting changes extended from the right VA to the right PICA, the hemorrhage was presumed to originate from a pseudoaneurysm located immediately distal to the right PICA origin; thus, embolization was limited to the right PICA. Parent artery occlusion was performed using coils, and the intended therapeutic outcomes were successfully achieved (Fig. 3C).
Computed tomography of the head reveals thick SAH, predominantly localized to the posterior cranial fossa, accompanied by ventricular enlargement indicative of hydrocephalus.
SAH: subarachnoid hemorrhage
Magnetic resonance imaging of the head performed 4 years prior to the onset of SAH demonstrates a well-visualized right VA.
(A: arrowheads) Meanwhile, contrast-enhanced computed tomography of the head obtained at the time of SAH onset fails to depict the right VA.
(B) Initial cerebral angiography performed at the onset of SAH reveals the right VA with irregular vessel caliber extending to the right posterior inferior cerebellar artery.
(C: arrow)
SAH: subarachnoid hemorrhage; VA: vertebral artery
Initial CAG performed at the onset of SAH revealed no evidence of an aneurysm.
(A) However, a subsequent CAG performed 30 mins later identified findings suggestive of a pseudoaneurysm at the origin of the right posterior inferior cerebellar artery (PICA).
(B: arrowheads) Coil embolization was performed at the origin of the right PICA to prevent rebleeding.
(C: arrows)
CAG: cerebral angiography; SAH: subarachnoid hemorrhage
On the day following the embolization, cranial decompression was required because of severe cerebrospinal fluid circulation impairment in the posterior cranial fossa caused by a thick SAH (Fig. 4A); however, the patient did not experience any further episodes of re-rupture. On the 7th day after onset, Magnetic resonance imaging of the head demonstrated a cerebral infarct in the PICA territory attributed to the embolization procedure, as well as additional infarcts in the brainstem and bilateral superior cerebellar artery territories, likely resulting from upward herniation (Fig. 4B). Fortunately, the patient survived the acute phase, and his clinical condition gradually stabilized. Owing to persistent hydrocephalus, the patient remained dependent on VD. Although shunt placement was considered, the patient's family declined further invasive treatment because of prolonged and severe disorientation. At the family's request, VD was discontinued, and the patient died on the 53rd day following the onset of SAH.
Computed tomography of the head on the day following embolization shows severe SAH in the posterior cranial fossa and marked compression of the fourth ventricle, indicating impaired cerebrospinal fluid circulation. (A) Magnetic resonance imaging of the head on day 7 demonstrates cerebral infarction in the posterior inferior cerebellar artery territory, consistent with the embolization procedure. Additional infarcts are observed in the brainstem and bilateral superior cerebellar artery territories, likely attributable to upward herniation. (B)
SAH: subarachnoid hemorrhage
AAV-associated cerebral aneurysms are rarely reported, and their pathogenesis remains poorly understood. It is hypothesized that during active vasculitis, inflammatory infiltration of the vascular wall leads to arterial wall weakening and rapid disruption, potentially resulting in luminal dilation and aneurysm formation.11) A histopathologically confirmed case of ruptured cerebral aneurysm associated with polyarteritis nodosa, a form of necrotizing vasculitis, was reported by Takahashi et al., supporting this mechanism.12)
Jingjing et al. reviewed previously reported cases of AAV with SAH and identified 34 cases of SAH associated with AAV, of which 12 cases were reported to have resulted from ruptured cerebral aneurysms.13) Including the additional case reported by Takahashi et al., a total of 13 cases of ruptured cerebral aneurysms associated with AAV have been documented (Table 1). These aneurysms were distributed across various regions of cerebral circulation, and the treatment approaches varied widely. Some cases underwent surgical intervention, while others were managed conservatively with medical therapy, including corticosteroid administration targeting the underlying vasculitis. Notably, while most aneurysms were saccular in morphology, 5 were classified as dissecting aneurysms.
Overview of Reported Cases of SAH Associated with AAV
| Author | Age (years) | Gender | Disease duration | Etiology | Location | Treatment | Outcome |
|---|---|---|---|---|---|---|---|
| AAV: anti-neutrophil cytoplasmic antibody associated vasculitis; ACA: anterior cerebral artery; MCA: middle cerebral artery; NR: not reported; PAO: parent artery occlusion; PICA: posterior inferior cerebellar artery; VA: vertebral artery | |||||||
| Muraishi et al. (1988)17 | 29 | Female | Present | Saccular | ACA | PAO | Remission |
| Takahashi et al. (2002)12 | 70 | Female | 1 year | Dissection | ACA | PAO | Remission |
| Takei et al. (2004)18 | 34 | Male | NR | Saccular | VA | Trapping | Remission |
| Sakamoto et al. (2005)14 | 36 | Female | 8 years | Dissection | VA | Coiling | Remission |
| Marnet et al. (2010)19 | 63 | Female | 4 years | Saccular | ACA | Clipping | Remission |
| Shimizu et al. (2011)20 | 60 | Female | 9 years | Saccular | NR | Conservative | Remission |
| Go et al. (2012)21 | 39 | Male | 9 months | Dissection | PICA | Coiling | Death |
| Kimura et al. (2012)15 | 44 | Female | 3 years | Dissection | PICA | Clipping | Remission |
| Menditto et al. (2013)22 | 64 | Female | 6 years | Saccular | PICA | Coiling | Remission |
| Ito et al. (2014)16 | 68 | Male | NR | Dissection | MCA | Conservative | Remission |
| Lee et al. (2017)23 | 48 | Female | 1 year | Saccular | VA | Conservative | Death |
| Harland et al. (2019)24 | 48 | Female | 4 months | Saccular | ACA, MCA | Conservative | Remission |
| Ihara et al. (2019)1 | 85 | Female | Present | Saccular | MCA | Clipping | Death |
| Present case | 86 | Male | Present | Dissection | PICA | PAO | Death |
In contrast to the previously reported cases, our patient's advanced age was a critical factor that initially led us not to suspect a dissecting cerebral aneurysm in the etiology. During the diagnostic process in this case, despite the absence of the right VA on contrast-enhanced CT, CAG revealed its presence along with subtle irregular vessel caliber changes extending from the right VA to the right PICA. Furthermore, this segment was initially not visualized on vascular imaging but subsequently became apparent on CAG, a finding that is highly suggestive of an evolving vascular lesion. Notably, no aneurysmal formation was observed on the initial angiogram; however, a pseudoaneurysm emerged clearly on repeat angiography performed just 30 mins later. The strikingly rapid morphological transformation-within such a short time frame-strongly indicated a dynamic and progressive vascular pathology, with dissection considered the most plausible etiology. Given that the patient was in the active phase of ANCA-associated vasculitis, it is highly likely that inflammatory infiltration into the vessel wall led to focal weakening and structural disruption, thereby predisposing the artery to dissecting pseudoaneurysm formation. Despite the patient's advanced age, we maintained a high index of suspicion for arterial dissection and conducted repeated vascular assessments, which ultimately confirmed the diagnosis and enabled prompt, targeted therapeutic intervention.
This case highlights the critical need to maintain the suspicion of dissecting aneurysms, even in elderly patients, particularly those with AAV presenting with SAH. Age-related vascular changes, such as atherosclerosis, can obscure the typical features of CAD, making the recognition of subtle vascular abnormalities essential. Our findings underscore the importance of comprehensive and repeated vascular imaging for detecting potential dissecting changes. This proactive diagnostic approach enables early detection and timely intervention, ultimately improving clinical outcomes.
ConclusionThis case highlights the importance of vigilance in the evaluation and management of SAH in elderly patients with AAV. Despite the rarity of this diagnosis in advanced age groups, clinicians should consistently consider the possibility of dissecting changes in patients with AAV to ensure timely intervention.
None of the authors received financial assistance for this study.
All authors have no conflict of interest.
