How to Correct a Misdiagnosis of MS

HILTON HEAD, SC—Given the lack of a definitive diagnostic test for multiple sclerosis (MS), diagnosing the disease can prove difficult. When considering symptoms, signs, and MRI findings that are suggestive of MS, clinicians must rely on their clinical judgment and experience, skillful interpretation of tests, and knowledge of and willingness to consider alternative diagnoses. Because of the subjective judgments involved and the many conditions that may mimic MS, it is not surprising that physicians sometimes misdiagnose MS, said Harold Moses, MD, at Vanderbilt University’s 41st Annual Contemporary Clinical Neurology Symposium.

A study by Solomon et al suggests ways to reduce the likelihood of misdiagnosis, said Dr. Moses, Associate Professor of Neurology at Vanderbilt University in Nashville. “Neurologists should … avoid overreliance on MRI changes as the principal support for an MS diagnosis,” he said. “Nonspecific or atypical MRI findings should be interpreted cautiously. A diagnosis of MS should not be made or reinforced in patients with psychiatric conditions without evidence for MS.”

For patients with emotional distress and psychologically based functional disability who do not meet diagnostic criteria for MS, a diagnosis of MS should be avoided. When MS remains a possibility, the patient should be informed of that fact and followed with clinical assessment and, if appropriate, MRI, Dr. Moses added. “Neurologists should be open in admitting and discussing uncertainty with patients,” he said. “It’s important to be honest in … indicating the need for further testing or observation over time. When emotional factors are thought to contribute [to a patient’s symptoms], treatments should be directed at these issues concurrently.”

First, Do No Harm

Psychiatrists and other therapists may be able to help patients when the diagnosis remains an open question. “MS disease-modifying drugs should be prescribed only for patients who have definitive evidence for MS or for those who present with classical clinically isolated syndromes—optic neuritis, transverse myelitis, and brainstem events—accompanied by appropriate changes on MRI,” Dr. Moses said.

Challenging cases include asymptomatic patients with MRI findings; patients with a first occurrence of symptoms, especially when the presentation is atypical; and patients with mimics of MS, such as vasculitis. Neurologists should be vigilant to identify mimics, particularly because these conditions may be treatable. The presence of psychiatric illness also may create challenging clinical scenarios.

“Psychologic and psychiatric factors may be present, but that patient may still have MS…. The question is, how do you tease out why that person is not doing well—that discordance, if you will, between how their MRI and exam are versus how they feel and how they are functioning.”

A Survey of Specialists

Solomon et al conducted a cross-sectional, internet-based survey of 242 MS specialists. Of the 50.4% of physicians who responded, 95% reported evaluating within the past year at least one patient who had been diagnosed with MS but who they felt strongly did not have the disease. More than 90% of respondents reported the use of disease-modifying therapy (DMT) in a proportion of these patients, and 94% found clinical encounters with these patients to be of an equal or greater challenge than making a new diagnosis of MS. A smaller proportion of respondents (14%) reported that, in some cases, they withheld telling a patient their opinion that the patient did not have MS.