Pathological findings of hypertrophic pachymeningitis associated with eosinophilic granulomatosis with polyangiitis

Hypertrophic pachymeningitis in ANCA-associated vasculitis: a cross-sectional and multi-institutional study in Japan (J-CANVAS)

BACKGROUND

This study investigated the characteristics of hypertrophic pachymeningitis (HP) in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), using information from a multicenter study in Japan.

METHODS

We analyzed the clinical information of 663 Asian patients with AAV (total AAV), including 558 patients with newly diagnosed AAV and 105 with relapsed AAV. Clinical findings were compared between patients with and without HP. To elucidate the relevant manifestations for HP development, multivariable logistic regression analyses were additionally performed.

RESULTS

Of the patients with AAV (mean age, 70.2 ± 13.5 years), HP was noted in 30 (4.52%), including 20 (3.58%) with newly diagnosed AAV and 10 (9.52%) with relapsed AAV. Granulomatosis with polyangiitis (GPA) was classified in 50% of patients with HP. A higher prevalence of GPA was significantly observed in patients with HP than in those without HP in total AAV and newly diagnosed AAV (p < 0.001). In newly diagnosed AAV, serum proteinase 3 (PR3)-ANCA positivity was significantly higher in patients with HP than in those without HP (p = 0.030). Patients with HP significantly had ear, nose, and throat (ENT) (odds ratio [OR] 1.48, 95% confidence interval [CI] 1.03-2.14, p = 0.033) and mucous membrane/eye manifestations (OR 5.99, 95% CI 2.59-13.86, p < 0.0001) in total AAV. Moreover, they significantly had conductive hearing loss (OR 11.6, 95% CI 4.51-29.57, p < 0.0001) and sudden visual loss (OR 20.9, 95% CI 5.24-85.03, p < 0.0001).

CONCLUSION

GPA was predominantly observed in patients with HP. Furthermore, in newly diagnosed AAV, patients with HP showed significantly higher PR3-ANCA positivity than those without HP. The ear and eye manifestations may be implicated in HP development.

Hypertrophic Pachymeningitis Development in Eosinophilic Granulomatosis with Polyangiitis at Relapse of Disease: A Case-Based Review

Hypertrophic pachymeningitis (HP) presents with thickening of the dura mater in the cerebrum and spine, and its symptoms vary depending on the affected location. The association of HP with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis has been recognized, and most cases are complicated by granulomatosis with polyangiitis. We report the case of a 47-year-old man who presented with HP upon relapse of eosinophilic granulomatosis with polyangiitis (EGPA), with literature review. He presented with disturbance of consciousness, and magnetic resonance imaging (MRI) revealed thickening of the dura mater around the left parietal lobe. Although myeloperoxidase (MPO)-ANCA was positive on EGPA diagnosis, the elevation of MPO-ANCA was not documented at the onset of HP. Brain perfusion scintigraphy showed an increase in blood flow in the left parietal lobe and temporal lobe, and electroencephalogram (EEG) revealed slow waves in the left parietal lobe. He was treated with a high dose of corticosteroid and rituximab, and the slow waves on EEG and brain perfusion were normalized. Although the most frequent symptom of HP is headache, disturbance of consciousness can be the manifestation of HP, and inflammation of HP could affect the cerebral parenchyma, which can be documented as abnormal EEG and perfusion scintigraphy. Literature review revealed that most of the HP in EGPA developed when EGPA relapsed, and was observed in patients with MPO-ANCA positivity. HP develops without evidence of other clinical features of EGPA; therefore, adequate imaging, including contrast-enhanced MRI, is necessary. Rituximab may be effective for treating HP complicated with EGPA.

Hypertrophic pachymeningitis in polyarteritis nodosa: a case-based review

Hypertrophic pachymeningitis (HP) is a rare neurological disorder with focal or diffuse thickening of the dura mater, which usually causes headache, cranial neuropathies, seizures, and motor or sensory impairments. The development of HP is attributed to an immune-mediated mechanism, and some autoimmune diseases have been implicated in the development of HP. Herein, we describe the case of a 73-year-old woman with persistent headache ascribable to HP, which developed approximately 3 years after a diagnosis of polyarteritis nodosa (PAN). She was treated with high-dose corticosteroid and cyclophosphamide that resulted in immediate disappearance of headache and improved radiological findings of thickened dura mater. In addition, she was subsequently administered methotrexate, ultimately resulting in maintenance of remission and regular reduction of prednisolone. In our review of published English articles, only two cases of HP in patients with PAN have been reported to date, suggesting that HP is a rare complication in PAN. However, it should be recognized that HP may develop as a neurological involvement related to PAN.