Intracranial granuloma mimicking a brain tumor in a patient with scleroderma
A 62-year-old female presented with a 3 month history of partial seizures, affecting the left arm and neck, lasting 2-3 minutes at a time. She also complained initially of some left arm clumsiness and weakness, which had progressed to include left leg weakness. Neurological examination revealed a left sided hemiparesis. She had significant past medical history, which included scleroderma, interstitial lung disease, pulmonary hypertension, and renal impairment. She was taking the immunosuppressant mycophenolate for interstitial lung disease. Magnetic resonance imaging [] revealed a solitary 27 × 22 mm enhancing right parafalcine lesion with surrounding edema and mass effect causing compression of the right lateral ventricle. The differential diagnosis included a dural-based metastasis or parafalcine meningioma. Due to her respiratory disease she was not fit enough for craniotomy and resection under general anesthesia and thus underwent an awake stereotactic biopsy of the lesion.\nHistopathological examination of the stereotactic biopsies [] showed white matter with diffuse foamy- or rod-shaped cells forming an occasional cluster, a few scattered bizarre gemistocytic astrocytes, and round cells. There were clusters and loose aggregate of round cells within loose fibrillary tissue. A few larger epithelioid cells and bizarre fibrillary cells were present. Necrosis was present and occasional plasma cells were found. There was no evidence of microorganisms and fungi on special stains (Periodic acid-Schiff Gram, Grocott, and Ziehl Neelsen stain). Immunohistochemistry showed a diffuse population of CD68-positive macrophages and histiocytes forming focal dense clusters and aggregate []. These were surrounded by a dense population of CD3-positive T-cells []. An occasional CD79a-positive B-cell was found. The appearances were consistent with a chronic inflammation of granulomatous type.\nShe completed a 3-week course of dexamethasone, 2 mg twice a day, and the hemiparesis resolved completely. Her initial seizures were managed with levetiracetam 500 mg twice a day. Follow-up imaging at 2 months [] revealed a decrease in the size of the lesion, and by 8 months the lesion had completely resolved [].