Character changes from idiopathic cranial pachymeningoencephalitis

Immunoglobulin G4–related hypertrophic pachymeningitis involving cerebral parenchyma

“…12,17,21 Since 1993, there have been 8 cases of cranial idiopathic hypertrophic pachymeningitis in which intraaxial inflammatory involvement was found (Table 1). 12,14,15,[17][18][19]27,28 In our case, this mass-forming lesion was located on the cerebral convexity, mimicking a meningioma. However, the presence of brain parenchymal involvement was very unusual.…”

“…In a diffuse type of idiopathic hypertrophic pachymeningitis, Matsushita el al. 18 performed biopsies in lesions with high signal intensity on T2-weighted images in the white matter as well as thickened dura mater. The biopsies revealed microglial proliferation and lymphocytic perivascular infiltration.…”

“…15 Cerebral parenchymal involvement is extremely rare; only 8 cases of pachymeningitis involving the cerebral parenchyma have been reported in the literature. 12,14,15,[17][18][19]27,28 Recently, the possibility that an IgG4-related sclerosing disease may represent a part of idiopathic hypertrophic pachymeningitis was suggested. 2,16 We report a case of pachymeningitis involving cerebral parenchyma that is associated with IgG4-related sclerosing disease.…”

Granulomatosis with Polyangiitis Presenting with Thrombovasculitic and Necrotizing Pachy- and Leptomeningitis Accompanied by a Brain Tumor-like Lesion

“…Bilateral Babinski's sign was attributable to a compressive disturbance of the pyramidal tracts by massive brain edema associated with the brain tumor-like lesion. Dural inflammation in HP can spread to the brain parenchyma leading to edema or even inflammatory cell infiltrates (pachymeningoencephalitis) while biopsy-proven cases with brain parenchymatous involvement have rarely been reported; for example, one such case with unknown HP etiology showed microglial proliferation in the cerebral parenchyma, and mild lymphocytic perivascular infiltration ( 5 ). However, brain tumor-like lesions with a midline shift are extremely rare in HP associated with ANCA-associated vasculitis and even with other etiologies ( 3 , 4 ); we found only one case with IgG4-related disease, who had a brain tumor-like mass lesion that showed obliterative phlebitis due to transmural and luminal aggregation of inflammatory cells by biopsy, in literature ( 6 ).…”