Weakness and Punctate Enhancement

Abstract

A 40-year-old man sought care for a 3-year history of tingling in his cheeks and face, with progressive urinary urgency. He had a 1-year history of progressive binocular diplopia and ataxia. On examination, he had decreased vibration sensation in his toes and a mild broad-based gait. Magnetic resonance imaging of the brain indicated mild fluid-attenuated inversion recovery abnormality with punctate postgadolinium enhancement, primarily in the pons. Spinal fluid analysis showed 2 white blood cells/µL with 95% lymphocytes, protein value of 32 mg/dL, 0 unique oligoclonal bands, and normal immunoglobulin G index. Pontine biopsy showed a polyclonal lymphocytic infiltrate, with a small polyclonal B-cell infiltrate. The patient was treated with intravenous methylprednisolone. His symptoms markedly improved, and repeated brain magnetic resonance imaging showed resolution of the enhancing lesions. Six months later he had progressive ataxia and pseudobulbar affect. Repeated brain magnetic resonance imaging showed a recurrence of the punctate enhancing lesions in the pons. A diagnosis of chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids was made. The patient was treated with weekly intravenous methylprednisolone, oral methotrexate, and folic acid supplementation. After 6 weeks, the methylprednisolone infusion interval was lengthened. Serial magnetic resonance imaging for 16 years after the original disease presentation showed no recurrence of enhancing brain lesions. Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids is an inflammatory brainstem disorder of unknown cause. It presents with a progressive pontocerebellar dysfunction associated with punctate enhancing lesions centered on the pons and cerebellum.