Chronic inflammatory demyelinating polyneuropathy evolving to primary CNS lymphoma

A 56-year-old woman presented with 3 months history of all four limbs' numbness in glove and stocking distribution. A week before admission, she developed all four limbs' weakness and numbness. Brain and whole spine imaging revealed no lesions, and cerebrospinal fluid showed high protein. A nerve conduction study revealed severe sensorimotor polyneuropathy, and she was diagnosed with chronic inflammatory demyelinating polyneuropathy. We treated her with plasma exchange and later developed bilateral pulmonary embolism, deep venous thrombosis and worsening of weakness. The second set of seven sessions of plasma exchange gave her improvement in muscle strength. However, after a chest infection, another neurological deterioration occurred. The third set of plasma exchanges resulted in excellent response. Nineteen months into her illness she developed a headache followed by left upper limb weakness and focal seizures with left side involvement. Brain imaging revealed a right frontal enhancing lesion that required resection, and biopsy showed diffuse large B-cell lymphoma. She was treated with chemotherapy and whole-brain radiation therapy and remained with left-sided weakness.