Multiple_sclerosis_PPMS_Criteria
Primary Progressive MS (PPMS) constitutes about 10% of MS cases and is characterized by a gradual increase in disability, often presenting as spinal cord syndrome. Diagnosed based on patient history and the McDonald criteria, it requires evidence of one-year progression and two out of three indicators: specific MRI lesions and cerebrospinal fluid oligoclonal bands. PPMS affects both genders equally, typically beginning around age 40.
Primary Progressive MS (PPMS) Overview
Primary progressive MS (PPMS) represents about 10% of MS cases. PPMS is characterised by progressive accumulation of disability from onset of the disease with occasional plateaus or temporary minor improvements. A diagnosis of primary progressive MS is made based on patient history, with no imaging or exam findings which distinguish PPMS from RRMS. PPMS is further classified as either active (with occasional relapses and/or evidence of new MRI activities) or not active. (1, 2)
Demographics and Clinical Presentation of PPMS
The mean age at onset of PPMS is approximately 40 years, which is about 10 years older than the mean age of RRMS patients and PPMS occurs equally in females and males, while RRMS occurs mainly in females. (3, 4) The most common clinical presentation of PPMS is spinal cord syndrome which worsens over months or years with asymmetric spastic paraparesis, gait difficulty and no clear sensory level. (5)
Diagnostic Criteria for PPMS
For diagnosis of PPMS, the McDonald criteria require evidence of 1 year of disease progression plus two of the three following criteria:
1-One or more hyperintense T2 MRI lesions characteristic of MS in one or more of the periventricular, cortical, juxtacortical or infratentorial regions.
2-Two or more hyperintense T2 MRI lesions in the spinal cord.
3-Presence of cerebrospinal fluid specific oligoclonal bands. (6)
References
1-Leary SM, Miller DH, Stevenson VL, et al. Interferon beta-1a in primary progressive MS: an exploratory, randomized, controlled trial. Neurology 2003; 60:44.
2-Buchter B, Dunkel M, Li J. Multiple sclerosis: a disease of affluence? Neuroepidemiology. 2012;39:51–6.
3-Montalban X. Overview of European pilot study of interferon beta-Ib in primary progressive multiple sclerosis. Mult Scler 2004; 10 Suppl 1:S62; discussion 62.
4-Luna G, Alping P, Burman J, et al. Infection Risks Among Patients With Multiple Sclerosis Treated With Fingolimod, Natalizumab, Rituximab, and Injectable Therapies. JAMA Neurol 2019.
5-Hawker K, O'Connor P, Freedman MS, et al. Rituximab in patients with primary progressive multiple sclerosis: results of a randomized double-blind placebo-controlled multicenter trial. Ann Neurol 2009; 66:460.
6-Polman CH, Reingold SC, Banwell B, Clanet M, Cohen JA, Filippi M, Fujihara K, Havrdova E, Hutchinson M, Kappos L, Lublin FD, Montalban X, O’Connor P, Sandberg-Wollheim M, Thompson AJ, Waubant E, Weinshenker B, Wolinsky JS. Diagnostic criteria for multiple sclerosis: 2010 revisions to the McDonald criteria. Ann Neurol. 2011;69:292–302.
