Author Topic: Myelocortical MS (MCMS), new MS subtype?  (Read 44 times)

0 Members and 0 Guests are viewing this topic.

Online agate

  • Administrator
  • *****
  • Posts: 8561
  • MS diagnosed 1980
  • Location: Pacific Northwest
MS Speaks--online for 13 years

SPMS, diagnosed 1980. Avonex 2001-2004. Copaxone 2007-2010.

Online agate

  • Administrator
  • *****
  • Posts: 8561
  • MS diagnosed 1980
  • Location: Pacific Northwest
MS Speaks--online for 13 years

SPMS, diagnosed 1980. Avonex 2001-2004. Copaxone 2007-2010.

Online agate

  • Administrator
  • *****
  • Posts: 8561
  • MS diagnosed 1980
  • Location: Pacific Northwest
From NEJM Journal Watch, September 25, 2018:


Multiple sclerosis with reduced neuronal densities and lack of cerebral demyelination
Robert T. Naismith, MD, reviewing Trapp BD et al., Lancet Neurol 2018 Oct 1


Multiple sclerosis (MS) is an autoimmune demyelinating disease characterized by white matter plaques with variable loss of axons. Investigators evaluated the pathologic characteristics of patients who appeared not to have demyelinating white matter lesions at autopsy.

Of 100 patients with MS who underwent autopsy, 12 had no visible white matter lesions on gross inspection of 1 cm slices; these patients were classified as having myelocortical MS (mMS). The mMS cases were matched with 12 individuals with typical MS (tMS), based on visible white matter lesions at autopsy.


The most common clinical phenotype in mMS was secondary progressive MS, but relapsing remitting and primary progressive MS were also represented. Cerebral white matter lesion area in mMS was 0.4 cm2 per hemisphere ó much less than the 14.14 cm2 in tMS. In the spinal cord, demyelination occupied 3.8% of the area per patient in mMS versus 13.8% in tMS. Subpial lesions were fewer in mMS as well, occupying 4.5% per patient compared with 9.7% for tMS. Neuronal density was reduced in layers III, V, and VI in mMS, but only in layer V in tMS, compared with healthy controls. Imaging parameters suggested a trend toward fewer T2 and T1 lesions in mMS. Investigators found similar measures in brain parenchyma fraction between mMS and tMS, and slightly increased cortical thickness in mMS compared with typical MS. Despite matching MRI T2-weighted lesions in mMS to the brain slices, the authors found no demyelination in those regions.


COMMENT

At autopsy, a small proportion of MS patients appeared to have neuronal degeneration without concomitant demyelinating disease. These mMS patients appeared similar to those with tMS in disease course and MRI findings. This study raises the question as to whether all MS is the same. Perhaps some patients have a primary neurodegenerative condition. Alternatively, neuronal degeneration may exist on a continuum, with cerebral-white-matter-dependent and independent pathways.


EDITOR DISCLOSURES AT TIME OF PUBLICATION
Disclosures for Robert T. Naismith, MD at time of publication

Consultant / Advisory board Alkermes; Acorda Therapeutics; Bayer HealthCare; Biogen Idec; EMD Serono; Genzyme Corp./Sanofi; Genentech; Novartis
Speakerís bureau Acorda Therapeutics; Biogen Idec; Genentech; Genzyme Corp./Sanofi

Grant / Research support  National Multiple Sclerosis Society; National Institutes of Health

CITATION(S):
Trapp BD et al. Cortical neuronal densities and cerebral white matter demyelination in multiple sclerosis: A retrospective study. Lancet Neurol 2018 Oct 1; 17:870. (https://doi.org/10.1016/S1474-4422(18)30245-X)

Note: The above link leads to the entire article.
« Last Edit: September 26, 2018, 07:39:05 pm by agate »
MS Speaks--online for 13 years

SPMS, diagnosed 1980. Avonex 2001-2004. Copaxone 2007-2010.