IgG4-related meningeal disease

Abstract

Objective To explore the clinical and pathological characteristics, diagnosis and differential diagnosis of IgG4-related meningeal disease.  Methods and Results A 49-year-old male patient suffered from headache for nearly 2 years and the symptom was aggravated progressively for over one month. MRI revealed space-occupying lesion in left parietal lobe, with irregular signal and clear borderline. Contrast-enhanced MRI showed homogeneous enhancement, and obvious meningeal thicking just like "dural tail sign". The patient underwent operation, and the lesion was totally removed. Histologically, it showed a large amount of hyperplastic collagen fibrous tissue with inflammatory cells, including a large number of plasmocytes, as well as scattered lymphocytes and a small number of eosinophilic granulocytes. Russell bodies which were homogenously positive for eosin could be seen in some plasmocytes. Focal necrosis, and proliferation of interstitial fibroblasts and small vessels were found. The lesion had no capsules and invaded surrounding tissues. Immunohistochemical staining showed the plasmocytes were diffusely positive for IgG and IgG4 (> 60%), and were positive for CD38 and CD138 on the membrane. Lymphocytes were positive for CD3, CD4 or CD20 on the membrane. The serum IgG4 level was 1.05 g/L. Final pathological diagnosis was IgG4-related meningeal disease in left parietal lobe. After operation, the patient received anti-infectious, anti-epileptic and nutrition support treatment, and the symptoms were markedly improved. The patient was discharged after 26 d, but was lost to follow-up.  Conclusions IgG4-related meningeal disease is a rare disease. Due to the atypical imaging features, it may be difficult to differentiate IgG4-related meningeal disease from other diseases with prominent inflammatory cells and stromal fibrosis. The elevated serum IgG4 level may provide diagnostic cues. However, a definite diagnosis depends on characteristic histological and immunohistochemical features.

DOI: 10.3969/j.issn.1672-6731.2016.03.010