Hypertrophic pachymeningitis in a southern Chinese population: a retrospective study

Abstract

Background Hypertrophic pachymeningitis (HP) is a fibrotic disorder featuring a thickening of the dura matter. Most HP studies were from Caucasian population and only a few studies of HP are available in China. In this study, we investigated the causes, clinical and imaging features and therapeutic implications of HP in a southern Chinese population.Methods We retrospectively analyzed 48 patients with HP with different causes from 1 January 2006 to 31 December 2018. Clinical manifestation, laboratory findings, neuroimaging results, and clinical course were evaluated in all HP patients.Results The mean age at onset was 50±12 years. The most common diagnosis was idiopathic HP (67%), followed by ANCA-associated vasculitis (15%), tuberculous meningitis (8%), viral meningitis (6%), and bacterial meningitis (4%). The main clinical manifestations were headache and cranial nerve deficits. The most frequently changed laboratory finding was elevated ESR. Imaging was characterized by cerebral or spinal dura matter enhancement in MRI scan with contrast. Enhancements were mainly located in the posterior fossa for idiopathic HP; frontal, parietal and occipital lobes for ANCA-related HP; and the posterior fossa for tuberculous-associated HP. Diffuse enhancement was found in most cases, except for tuberculous-associated HP. Glucocorticoid or immunosuppressive treatment were applied in most cases.Conclusions HP was diagnosed based on clinical manifestations, imaging and laboratory results. Etiology varied among patients, with idiopathic HP being the most common. MRI with contrast showed enhancement of the dura matter, which differed according to different etiologies. Glucocorticoid or immunosuppressive agents were the primary drugs for treatment.

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

“…Although patients with HP rarely had mononeuritis multiplex, which is also ascribable to small-to medium-sized vasculitis [4,29], the manifestations typically attributable to vasculitis might be little associated with HP development. It has been assumed that direct extension and/or transfer to the CNS from upper respiratory lesions, including granulomatosis inflammation, may be implicated in the mechanism for developing HP related to AAV [15,16,30]. Accordingly, our study also suggested that inflammatory lesions adjacent to the CNS, notably including eye and middle ear involvement, may be robustly implicated in HP development in AAV.…”

“…Several single-center studies on ANCA-associated HP have been presented to date; however, it might be difficult to accurately determine the clinical characteristics contributing to HP development in AAV because of the limited number of patients analyzed at each institution. Considering the ethnic viewpoint of ANCA-associated HP, the majority of published studies have been reported from East Asian counties including Japan [8,10,[15][16][17][18][19][20]. Consequently, this was the first study to assess the clinical characteristics of HP using the enrolled information from many Japanese patients with AAV, demonstrating the epidemiological findings, especially the frequency of HP and classification in AAV, as more reliable results…”

“…HP could develop as the first clinical episode of AAV, whereas approximately 15% of patients with HP, even with serum positivity for ANCA, cannot be classified as having definite AAV [10,12], suggesting that HP could be a CNS-limited type of AAV [8,10]. Moreover, patients with immune-mediated HP showing serum positivity for ANCA without a definite classification of AAV have been comprehensively categorized as ANCAassociated HP [10][11][12][13][14][15][16]. Given these unclassifiable categories of immune-mediated HP with ANCA positivity, it is necessary to specifically understand the clinical characteristics of HP developing in AAV.…”

IgG4-related hypertrophic pachymeningitis with tumor-like intracranial and intracerebral lesions

“…The most common neurological symptoms of patients suffering from IgG4-related hypertrophic pachymeningitis are headache and cranial nerves palsies, followed by motor or sensory deficits, seizures, and ataxia. Headache may reflect meningeal inflammation [2,34]. Cranial nerve palsies are usually due to compression by the thickened dura mater [4,23].…”

“…High-dose methylprednisolone therapy (1 g/day for 3 days) has been recommended in patients with acute severe neurological deficits [2]. Another strategy is the concomitant use of immunosuppressive agents such as methotrexate (20 mg/ week), azathioprine (100-200 mg/day), mycophenolate mofetil (1000 mg twice daily), and cyclophosphamide (either oral 100 mg/day) [21,34]. In our series, adjuvant therapy was used as a steroid-sparing strategy in all instances.…”