Eosinophilic vasculitis in an isolated central nervous system distribution

Tumefactive eosinophil-rich non-granulomatous small vessel vasculitis in the cerebrum in a patient with idiopathic hypereosinophilic syndrome

The definite diagnosis of central nervous system vasculitis requires pathological verification by biopsy or surgical resection of the lesion, which may not always be feasible. A 74-year-old woman with a history of allergic rhinitis, but not asthma, presented with slowly progressive left hemiparesis. Magnetic resonance imaging of the head revealed a heterogeneously enhancing mass involving the right internal capsule and corona radiata. Histological examination of the resected specimen revealed eosinophil-rich non-granulomatous small vessel vasculitis with no neutrophil infiltration or foci of microbial infection. Epstein-Barr virus in situ hybridization was negative, and polymerase chain reaction tests for both T-cell receptor gamma and immunoglobulin heavy-chain variable region genes did not show rearrangements, excluding the possibility of lymphoma and lymphoproliferative disorders. Blood hypereosinophilia and elevated erythrocyte sedimentation rate were observed; however, anti-neutrophil cytoplasmic antibodies were not detected. A biopsy of the erythema in the hips and thighs revealed perivasculitis with eosinophilic infiltration within the dermis. Chest computed tomography revealed multiple small nodules in the lungs. Her symptoms, aside from hemiparesis, disappeared after corticosteroid administration. The clinicopathological features were similar to eosinophilic granulomatosis with polyangiitis but did not meet its current classification criteria and definition. This patient is the first reported case of idiopathic eosinophilic vasculitis or idiopathic hypereosinophilic syndrome-associated vasculitis affecting the small vessels in the brain. Further clinicopathological studies enrolling similar cases are necessary to establish the disease concept and unravel the underlying pathogenesis.

"Idiopathic Eosinophilic Vasculitis": Another Side of Hypereosinophilic Syndrome? A Comprehensive Analysis of 117 Cases in Asthma-Free Patients

BACKGROUND

The absence of asthma may rule out a diagnosis of eosinophilic granulomatosis with polyangiitis in patients with hypereosinophilic syndrome (HES) and features of vasculitis.

OBJECTIVE

To describe eosinophilic vasculitis (EoV) as a possible manifestation of HES in asthma-free patients.

METHODS

We screened our hospital database and the literature for patients with HES who met the following 4 criteria: (1) histopathological or clinical features of EoV (biopsy-proven vasculitis with predominant eosinophilic infiltration of the vessel wall and/or features of vasculitis with tissue and/or blood hypereosinophilia [absolute eosinophil count >1.5 G/L]); (2) no other obvious causes of reactive eosinophilia, organ damage, and vasculitis; (3) the absence of antineutrophil cytoplasmic antibodies; and (4) the absence of current asthma.

RESULTS

Ten of our 83 (12%) asthma-free patients with HES and 107 additional cases in the literature met the criteria for EoV. After a critical analysis of the patients' clinical and laboratory characteristics and outcomes, we identified 41 cases of single-organ EoV (coronary arteritis, n = 29; temporal arteritis, n = 8; cerebral vasculitis, n = 4). Of the remaining 76 patients with EoV, the most frequent manifestations (>10%) were cutaneous vasculitis (56%), peripheral neuropathy (24%), thromboangiitis obliterans-like disease (16%), fever (13%), central nervous system involvement (13%), deep venous thrombosis (12%), and nonasthma lung manifestations (12%). Blood hypereosinophilia more than 1.5 G/L was observed in 79% of patients, and necrotizing vasculitis was observed in 44%.

CONCLUSIONS

Our results suggest that idiopathic EoV (HES-associated vasculitis) can be classified as an eosinophilic-rich, necrotizing, systemic form of vasculitis that affects vessels of various sizes in asthma-free patients.

Eosinophilic meningitis caused by primary angiitis of the central nervous system

Eosinophilic meningitis is defined as the presence of 10 eosinophils/mm(3) in the cerebrospinal fluid (CSF) or eosinophils accounting for more than 10% of CSF leukocytes. A 76-year-old man who developed cognitive dysfunction and consciousness disturbance had eosinophilic meningitis (his CSF contained 19.0% eosinophils). Because the etiology was unknown, we performed a brain biopsy. The pathological findings showed inflammatory infiltration in the small-sized arteries of the meninges. The patient was ultimately diagnosed as having primary angiitis of the central nervous system (PACNS). Eosinophilic meningitis occurring in a patient with PACNS is extremely rare, and this is the first report of this condition in Japan.

Challenges in diagnosis of isolated central nervous system vasculitis

Isolated central nervous system (CNS) vasculitis is a rare and complicated disorder. Patients typically present with nonspecific neurologic symptoms such as headache and encephalopathy, and have variable progression and severity of the disease. Challenges to definitive diagnosis include the limitations of currently available diagnostic modalities with high likelihood of false-positive or false-negative findings. Imaging, serologic, and cerebrospinal fluid (CSF) evaluation, and even angiography can fail to establish the diagnosis. Often, brain biopsy is required. In order to illustrate these challenges, we report the case of a patient who presented with subacute cognitive decline and was ultimately diagnosed with isolated CNS eosinophilic vasculitis. Initial work-up included CSF and serologic analyses, magnetic resonance imaging (MRI), and cerebral angiography, but definitive diagnosis required brain biopsy. Immunosuppressive therapy resulted in clinical improvement and stabilization. To our knowledge, only one other case of isolated CNS eosinophilic vasculitis has been reported in the literature. We discuss the importance of a high index of clinical suspicion in cases of progressive nonspecific neurologic symptoms.

Eosinophilic vasculitis of the spinal cord associated with Churg-Strauss syndrome

Eosinophilic vasculitis has been described as part of Churg-Strauss syndrome (CSS), but it also affects the central nervous system in <10% of cases. However, spinal cord involvement in CSS has not been reported. We report a patient with myelopathic symptoms, with a two-year history of asthma. Laboratory tests revealed leukocytosis, with 31.7% eosinophils. A chest computed tomographic scan and radiography showed patchy bilateral areas of consolidation, predominantly involving the peripheral regions of the lower lobes. Spinal cord magnetic resonance imaging (MRI) revealed high-signal-intensity lesions at the C3-C5 and T1-T4 spinal levels on T2-weighted images. A microscopic evaluation revealed an eosinophil-rich inflammatory infiltrate with fibroid necrosis of a vessel wall, and granuloma formation in the small veins was not clearly visible. To the best of our knowledge, this is the first case of eosinophilic vasculitis of the spinal cord associated with CSS, and the patient responded well to steroids.