Hypertrophic pachymeningitis (HP). overview of the underlying etiology, presentation & management

Abstract

Hypertrophic pachymeningitis (HP) is a rare chronic inflammatory dural pathology. It is classified into idiopathic by exclusion, or associated with underlying pathology like tuberculous meningitis, rheumatoid arthritis, syphilis, Wegener’s granulomatosis, IgG4 related disease and neoplasm. Objective: we try to review the etiology, clinical presentation & management & to review the literature on HP. this was retrospective study of 12 patients (7 men, 5 women), with age range between 20 to 75 years), they were diagnosed as HP (8 cranial & 4 spinal) by imaging studies & histopathology. The clinical features, serological, biochemical & radiological studies, treatment & outcome were followed over one year. The underlying etiology were so that 5 cases were idiopathic (IHP), 3 cases were associated with tuberculous meningitis, 2 cases were diagnosed in patients with rheumatoid arthritis & 2 cases were confirmed to be IgG4 related disease. The main clinical features at presentation were headache, cranial nerves neuropathy in cranial HP & limb sensory/motor dysfunction in spinal HP. On MRI, the enhancement & thickening of the dura mater correlated with the clinical presentation. Histopathological study from 8 patients demonstrated infiltrates of small mature lymphocytes, plasma cells, macrophages and epithelioid histiocytes. Corticosteroid therapy improved or stabilized the condition in 9 of 12 cases. Four cases need surgical intervention & have improvement. Three cases had progressive worsening & deterioration despite steroid therapy, two of them refused surgery & referred for chemotherapy but we missed them from our study without a feedback. Follow-up MRI performed in all patients. the diagnosis of HP is based on serological, MRI & histopathological studies. Idiopathic cases were diagnosed by exclusion. Steroid therapy control the disease progression. In symptomatic cases with mass effect & neurodeficit, surgery is indicated.