Professor Belahsen looking at patient x-rays, Fes, Morocco.

MS is a complex disease. Children, teens and adults with MS experience a wide range of different symptoms, and many of these symptoms are common to other conditions too. Diagnosing MS is not simple. Neurologists perform a range of tests that can suggest whether someone has MS (as outlined in the 2017 McDonald diagnostic criteria), but there is no blood test that can diagnose MS and MRI pictures cannot always distinguish MS from other conditions.

When making the diagnosis of MS, adult and pediatric neurologists have to rule out other diseases, ensuring that there is ‘no better explanation’ for the symptoms apart from MS. These possible other explanations are also referred to as “differential diagnoses”.

The first consensus guidelines about the differential diagnosis of MS were published in 2008, and experts agreed there was a need to update these guidelines. This was echoed in a recommendation arising from a meeting that MSIF convened in 2019,  to discuss the key global challenges around access to MS healthcare. In particular, experts believed that the updated guidelines needed to take greater account of differential diagnoses that are more commonly seen in regions of the world such as Africa, South East Asia and the Eastern Mediterranean, and to consider differential diagnoses that vary based on how old a person is with specific attention to children and to older adults.

With the increased knowledge about MS and diseases that can cause similar symptoms, an update to the consensus recommendations was timely. ACTRIMS (the Americas Committee for Treatment and Research in MS) took the lead on this project, and brought together neurologists with experience of MS from many different countries around the world. The MS Differential Diagnosis Consortium – which included the Chair and Deputy Chair of MSIF’s international medical and scientific board (IMSB), Professor Brenda Banwell and Dr Jorge Correale, and was led by multiple world experts in MS – has now published their updated 2023 consensus on the differential diagnosis of MS.

Professor Brenda Banwell, Chair of the IMSB says:

“The new guidelines will serve as a very valuable resource for clinicians worldwide. With the many effective therapies for MS that now exist, it is essential that persons with MS are diagnosed quickly and accurately, so that these therapies can be made available to reduce the impact of this disease.”

The updated guidelines discuss a range of other conditions that have some similarity to MS, and provides detailed guidance about how to distinguish them. In addition, the guidelines note that age, race, ethnicity, genetic ancestry and geographic region are important considerations in MS differential diagnosis. These topics will be explored in greater detail in upcoming manuscripts resulting from the MS Differential Diagnosis Consortium.

Dr Jorge Correale, Deputy Chair of the IMSB says:

“As a neurologist practising in Argentina, I understand the challenges of adapting global guidelines to the local context in different countries. These updated guidelines, and the additional topics that will follow, will help neurologists in all parts of the world to achieve an accurate diagnosis for people with MS.”

We know that guidelines alone are not enough if we want to see real change for people with MS. Data from the Atlas of MS shows there are many different barriers to diagnosing MS across the world, including whether healthcare professionals are aware of the latest guidelines relating to the diagnosis of MS.

Professor Andrew Solomon, lead author of these updated consensus guidelines says:

“It is important now to consider how the updated guidelines can be disseminated as widely as possible, to enable more people with suspected MS to receive a quick and accurate diagnosis of their condition.”

Access the full updated consensus guidelines here: “Differential diagnosis of suspected multiple sclerosis: an updated consensus approach” by Andrew J Solomon, Georgina Arrambide, Wallace J Brownlee, Eoin P Flanagan, Maria Pia Amato, Lilyana Amezcua, Brenda L Banwell, Frederik Barkhof, John R Corboy, Jorge Correale, Kazuo Fujihara, Jennifer Graves, Mary Pat Harnegie, Bernhard Hemmer, Jeannette Lechner-Scott,
Ruth Ann Marrie, Scott D Newsome, Maria A Rocca, Walter Royal III, Emmanuelle L Waubant, Bassem Yamout, and Jeffrey A Cohen is published in Lancet Neurology (published online July 19, 2023).

Find further information about improving access to MS diagnosis here.