May 30, 2012
A diagnosis of MS sometimes occurs in people who are later found to not have the disease. Andrew Solomon, MD (University of Vermont College of Medicine) and colleagues at Oregon Health and Science University evaluated survey results from 122 doctors specializing in MS to find out why and how often this happens. Survey results were published early online on May 11, 2012 in the journal Neurology.
Background: Diagnosing multiple sclerosis can be challenging, and is made after considering many types of information, including neurological exam, symptoms, MRI scans, and laboratory assessments. Through international initiatives launched by the National MS Society, the diagnostic criteria for MS were developed and updated in 2010, and guidance on ways to differentiate MS from look-alike disorders were published in 2008. Being incorrectly diagnosed with MS can have important psychological, economic, and treatment implications for individuals and their families.
Study: Dr. Solomon and colleagues conducted an online survey of MS specialists, largely in the United States. Of 242 individual neurologists originally contacted, 122 completed the survey. MS specialists are often consulted after a person has initially been diagnosed by a non-specialist. The survey focused on determining how often MS specialists encounter patients who are misdiagnosed with MS, and the characteristics of these patients.
The results showed that:
• Almost all (95%) of the survey respondents had encountered at least one patient who had been misdiagnosed with MS, and about 40% had seen 3 to 5 patients over the last year that they felt had been misdiagnosed with MS.
• Most reported that a portion of those they felt had been misdiagnosed with MS were taking an MS disease-modifying therapy; about one-quarter of the respondents reported that three-quarters of the misdiagnosed patients were taking disease-modifying therapy that was inappropriate in the absence of MS.
• Most found it challenging to inform individuals that they did not have MS, but most did so. Around 14% of respondents had chosen not to inform some patients of the misdiagnosis for a variety of reasons, including risk of psychological harm to the patient; consequences of benefits and finances that would negatively impact the patient; and belief that “undoing” the diagnosis should be the responsibility of the physician who originally made the diagnosis.
• Alternative and likely diagnoses made by respondents for patients incorrectly identified as having MS included non-specific brain abnormalities, small blood vessel ischemic disease, migraines, psychiatric diseases, fibromyalgia, neuromyelitis optica, and several others.
Comment: An accompanying editorial by Richard Rudick, MD (Cleveland Clinic; Chair of the National MS Society’s Research Programs Advisory Committee) and Aaron Miller, MD (Mount Sinai School of Medicine, New York; Chief Medical Officer of the National MS Society) notes that because there is still no definitive diagnostic test for MS, the problem of misdiagnosis persists, possibly because of over-reliance on MRI imaging. They recommend that physicians perform thoughtful and complete assessments of symptoms and laboratory results when making a diagnosis, in light of the fact that although early initiation of disease-modifying drugs in people with definite MS is beneficial, there should be a high level of confidence in the diagnosis before a person goes on long-term disease-modifying therapies, the use of which “entails risk, discomfort, inconvenience, and high cost.”