In the second part of our MD P&P article on multiple sclerosis, our panelists discuss the role of the McDonald criteria, clinically definite MS, and the impact of the disease.
Multiple sclerosis (MS) is a chronic autoimmune disorder that affects the central nervous system, resulting in inflammation and damage to myelin and neurons within the nervous system. While the exact cause of MS is unknown, environmental, viral, and genetic factors are all thought to play important roles.
MD Magazine: Peers and Perspectives recently convened three of the nation’s leading MS experts: Douglas Jeffery, MD, PhD, neurologist for Advance Neurology and Pain, Cornerstone Health Care; R. Philip Kinkel, MD, director of the MS program at Beth Israel Deaconess Medical Center, Harvard Medical School; and Robert Zivadinov, MD, PhD, professor of neurology at the University at Buffalo, State University of New York. The panel was moderated by Peter Salgo, MD, a professor of anesthesiology and internal medicine at Columbia University.
Too Much Attention to McDonald Criteria?
To establish some context for the discussion, Salgo asked if there was a difference between the McDonald criteria and clinically definite MS. “The traditional criteria that my colleagues were alluding to is the clinical definition of MS, which, broadly speaking, can be stated as a syndrome that is consistent with inflammatory demyelination, that is disseminated throughout the central nervous system in space, meaning different areas of the central nervous system, and over a time interval,” replied Kinkel. He added that the way neurologists diagnose MS has evolved over time to allow ancillary measures, predominantly the MRI, to substitute for clinical measures of dissemination in space and time.
“That’s a very different scenario than when I was in medical school or even fairly recently,” noted Salgo. The McDonald criteria have both pros and cons, said Kinkel. “The benefit of criteria that allow you to diagnose earlier is that you can potentially apply treatments earlier,” he said, adding that the downside is an incomplete understanding of risk factors for future disease progression.
Kinkel provided two extreme patient scenarios. “We could see an individual who comes in with an optic neuritis, and on an MRI scan they have a solitary lesion abutting the periventricular white matter. You see another individual just like that who comes in, and they have more lesions that you can count,” he said, pointing out that both individuals have a 90% chance of developing MS. “However, the patient with more lesions would have a far greater chance of having progressive disease and a far greater chance of having disability at the 15-year point than the other individual.”
“At those extreme levels, we can make some judgments and some predictions,” Kinkel said. “But the problem is that most people fall somewhere in between, and we don’t have the best measures to define who will develop problems.”
Zivadinov added that he felt the criteria are being revised too frequently. All three panelists agreed that neurologists sometimes pay too much attention to criteria and not enough to their patients’ symptoms.
How should early MS be differentiated from some other disorder that would require a different treatment regimen, Salgo asked.
“One of the tenets in the diagnosis of MS states that you have to have lesion dissemination in time and in space and the absence of a more likely explanation,” replied Jeffery, adding that other disease processes, which can mimic multiple sclerosis, have to be ruled out. “One of the most relevant mimics that have come to light recently is Sjögren’s syndrome, which can produce spinal cord lesions that look very much like MS lesions.”
What Is the Impact of MS?
What is the predominant impact of the early stages of MS, especially in young patients, asked Salgo.
“There are huge consequences with MS,” replied Jeffery, pointing out that one of the condition’s earliest-presenting symptoms is severe fatigue, which can impair patients’ daily functioning and ability to work. “They may have problems with pain, bladder dysfunction, bowel dysfunction, sexual dysfunction, and cognitive function.” Early on, he added, most patients report that their memory has deteriorated even though their neuropsychological exam reveals little.
Kinkel added that mood disorder is another prominent early symptom of MS often overlooked by clinicians. “Depression and anxiety occur in early MS way out of proportion to either the chronicity of the disease state or the severity of the impairment,” he said. Could an MS patient’s mood disorder be attributed to an anatomic problem in the brain, or would it be better understood as a response to a horrifying diagnosis, Salgo asked.
“I think it’s both,” replied Jeffery. “When patients have widespread inflammatory changes in their nervous system, it triggers many of these symptoms. He added that some of these symptoms can be ameliorated by effective therapies.
Is There a Role for Primary Care Providers?
Salgo then shifted the conversation to the role of primary care providers (PCPs). “They have experience in chronic disease and in chronic medication management,” he said. “Do you see primary care physicians playing a more predominant role in managing patients with MS?"
“No,” said Jeffery. “I think most primary care physicians are scared to death of an MS patient. They have no idea what to do with them, and they’re worried that anything they do could make it worse.”
Salgo then asked whether PCPs should be more involved in caring for patients with MS.
"Neurology has taken too much of a back seat in medical education, so many primary care physicians feel inadequate to the task", said Kinkel. “And then you throw in something such as MS, which has so many weird effects or perceived weird effects. We’re handling calls all the time. ‘Why am I having this rippling in my belly muscles? Why am I having this pain here? Why am I having this electrical shock here?’”
Kinkel agreed, recalling how frequently his MS patients report that their dentists can’t find a cause for their facial pain—little surprise given that dentists receive little education about trigeminal neuralgia. “They’ll pull a couple of teeth before they figure out that maybe it is time to consult a neurologist,” he said, adding that since PCPs usually defer to neurologists, “traditionally, we’ve been the patient’s primary care physician.”
1. Kurtzke JF. Rating neurologic impairment in multiple sclerosis: an expanded disability status scale (EDSS). Neurology. 1983;33:1444-1452.
2. Brex PA, Ciccarelli O, O’Riordan JI, et al. A longitudinal study of abnormalities on MRI and disability from multiple sclerosis. N Engl J Med. 2002;346:158-164.
We want to know what you think:Do you pay more attention to the McDonald criteria or your patients’ symptoms when diagnosing MS?To read the rest of this article, click here.