Hypertrophic Pachymeningitis in Eosinophilic Granulomatosis with Polyangiitis

A Rare Case of Spinal Hypertrophic Pachymeningitis That Caused Tetraplegia After Myelography

Hypertrophic pachymeningitis (HP) is a rare inflammatory disease that causes the thickening of the dura mater. Its etiology is mainly classified as idiopathic or secondary, and autoimmune disease is one of the main causes of secondary HP. Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis and IgG4-related disease are common among autoimmune diseases. Here we present a case of spinal HP in which the patient showed spinal shock and neurological symptoms deteriorated after myelography. Since the patient was sedated without caution of the neck posture, the HP itself compressed the spinal cord, which led to the tetraplegia. To our knowledge, this is the first case report of such an entity. Our case highlights the risk of sedation for patients who have hypertrophic lesions of the dura mater.

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.