A 22-year-old woman comes to the physician with her husband for intermittent dizziness, weakness, and unsteady gait for the last several weeks. She has also had visual loss and pain in the right eye that worsens with eye movement for the past 2 days. A year ago, the patient had tingling and numbness of her right hand accompanied by unsteadiness, which improved spontaneously after 3-4 days. She has no other medical problems and does not take any medications. The patient has no significant social or family history. Her temperature is 37.2 C (99 F) , blood pressure is 122/80 mm Hg, pulse is 82/min, and respirations are 16/min. On neurologic examination, her right eye has diminished visual acuity and an afferent pupillary defect. She also has a right arm intention tremor. Both lower extremities have spastic paresis, hyperreflexia, and positive Babinski sign. Item 1 of 5
Which of the following is the most appropriate test to confirm the diagnosis in this patient?

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Explanation: 11ec2b69_bffc_f87b_8f63_1b3705cfb2e9_MD0005_00 This patient likely has multiple sclerosis (MS) as her neurologic deficits are disseminated in time and space. Relapsing-remitting MS is the most common pattern and is characterized by neurologic recovery between episodes of acute exacerbations. Nearly 50% of MS patients develop optic neuritis, which typically presents with monocular visual loss accompanied by eye pain that worsens with eye movement. Patients can also develop transverse myelitis resulting in upper motor neuron signs and sensory loss below the level of spinal involvement. This patient's dizziness and right arm intention tremor are concerning for cerebellar involvement as well. The diagnosis of MS is supported with MRI revealing hyperintense lesions in the brain and/or spinal cord on T2-weighted images. Ovoid-shaped periventricular white matter lesions can be seen in 23%-75% of patients. MRI is superior to CT in evaluating posterior fossa/cerebellar abnormalities and is more sensitive/specific in detecting MS lesions (Choice A). periventricular white matter lesions (Choices B and E) Evoked potentials (eg, visual, auditory, somatosensory) can identify silent central nervous system lesions. Nerve conduction studies and electromyography can be useful in distinguishing neuropathic versus myopathic weakness, respectively. These studies have limited diagnostic utility in the evaluation of MS. (Choice C) Lumbar puncture is not required for the diagnosis of MS and is usually performed in atypical cases to confirm the diagnosis. Oligoclonal bands and elevated IgG index can be seen in >90% of cases. Opening pressure and other cerebrospinal fluid measures are typically normal. Educational objective: MRI is the preferred test to support the diagnosis of multiple sclerosis and typically shows ovoid-shaped periventricular white matter lesions. Lumbar puncture can confirm the diagnosis in equivocal cases and may demonstrate oligoclonal bands and an elevated IgG index. References: Multiple sclerosis: a primary care perspective. (http://www.ncbi.nlm.nih.gov/pubmed/25368924)

A 22-Year-Old Woman Comes to the Physician with Her Husband