Classification, diagnosis, and differential diagnosis of multiple sclerosis.

PURPOSE OF REVIEW The increasing availability of effective therapies for multiple sclerosis as well as research demonstrating the benefits of early treatment highlights the importance of expedient and accurate multiple sclerosis diagnosis. This review will discuss the classification, diagnosis, and differential diagnosis of multiple sclerosis. RECENT FINDINGS An international panel of multiple sclerosis experts, the MS Phenotype Group, recently revised the multiple sclerosis phenotypic classifications and published their recommendations in 2014. Recent research developments have helped improve the accuracy of multiple sclerosis diagnosis, especially with regard to differentiating multiple sclerosis from neuromyelitis optica spectrum disorders. SUMMARY Current multiple sclerosis phenotypic classifications include relapsing-remitting multiple sclerosis, clinically isolated syndrome, radiologically isolated syndrome, primary-progressive multiple sclerosis, and secondary-progressive multiple sclerosis. The McDonald 2010 diagnostic criteria provide formal guidelines for the diagnosis of relapsing-remitting multiple sclerosis and primary-progressive multiple sclerosis. These require demonstration of dissemination in space and time, with consideration given to both clinical findings and imaging data. The criteria also require that there exist no better explanation for the patient's presentation. The clinical history, examination, and MRI should be most consistent with multiple sclerosis, including the presence of features typical for the disease as well as the absence of features that suggest an alternative cause, for a diagnosis of multiple sclerosis to be proposed.