The criteria for diagnosing relapsing forms of MS require evidence of at least two separate areas of damage in the central nervous system (CNS) that have occurred at different points in time, with no other possible explanation. Because people with PPMS do not experience easily identifiable — or easily countable — inflammatory attacks (also called relapses or exacerbations) in the CNS, the physician must look for somewhat different evidence in order to make the diagnosis:
- At least one year of progressively worsening neurologic symptoms that look like MS, AND
- Two out of three of the following:
- Nine or more MS-like brain lesions on magnetic resonance imaging (MRI) or at least 4 MS-like brain lesions + positive results on visual evoked potential (VEP) testing indicating impaired transmissions in the optic nerve.
- MS-like spinal-cord lesions on MRI
- Analysis of cerebrospinal fluid (obtained by lumbar puncture, often called “spinal tap”) indicating an abnormal immune response in the central nervous system that is consistent with MS
This means that diagnosing PPMS can sometimes take a fairly long time — particularly if the person has only recently begun to experience neurologic symptoms.
Please explore the following pages to learn more about PPMS.
- How primary-progressive MS differs from relapsing forms of MS
- How primary-progressive MS is treated
- Research in primary-progressive MS
- FAQ’s about primary-progressive MS