Clinical, Radiological, and Etiological Aspects of Pachymeningitis: A Study of 24 Cases

Abstract

Introduction and importance Hypertrophic pachymeningitis (HP) is an uncommon disorder with varied etiological origins and heterogeneous clinical presentation. Establishing the etiological diagnosis poses a challenge, but prompt identification provides a treatment window, potentially leading to a reversal of symptoms. MRI is the reference examination, allowing not only the early diagnosis of pachymeningitis but also the assessment of its extent and importance, detection of possible complications, and suggestion of etiology. Case presentation We conducted a retrospective study involving 24 patients recruited over 5 years for who brain imaging had revealed the presence of pachymeningitis. The average age of the patients was 40 years, with a male-to-female ratio of 0.6. Clinical discussion Headache was present in 54.17% of patients. All the patients underwent MRI examinations utilizing different sequences, with subsequent Gadolinium injection showing localized and asymmetrical meningeal thickening in 13 cases, and diffuse in the rest. The cerebrospinal fluid study unveiled an inflammatory fluid characterized by a lymphocytic predominance and hyperproteinorrhea, noted in 50% of the patients. The histopathological analysis of a stereotactic biopsy conducted on an individual patient revealed non-diagnostic results. The etiological investigation was dominated by tuberculosis, which was detected in 33.3% of cases. Idiopathic origin was identified in 16.7% of patients. Conclusion Meningeal thickening is rare, and the multitude of potential causes makes the etiological investigation challenging unless they fall within the scope of secondary meningeal disorders; otherwise, a dural biopsy becomes necessary, and the prompt initiation of treatment, along with determining the etiology influences the prognosis.

Keywords: cerebral tuberculosis; hypertrophic pachymeningitis; infiltration of the dura mater; mri; sarcoidosis.

Figure 1. Brain MRI with T1-weighted sequence post-gadolinium injection, sagittal (A) and axial (B, C) sections revealing diffuse meningeal thickening (white arrows)

Figure 2. Brain MRI, axial section with T1-weighted sequence post-gadolinium injection, and sagittal T1-weighted sequence of a 47-year-old female patient with neurosarcoidosis associated with a left temporal 70 mm long-axis liquid lesion

*: Diffuse micro and macronodular thickening of the meninges above and below the tentorium with a predominantly hemispheric involvement in the left periventricular and pericallosal areas, hyperintense on FLAIR, enhancing significantly after contrast administration. a: Pachymeningitidis FLAIR: fluid-attenuated inversion recovery