Inflammation in the meninges linking to Grey matter pathology

Howell OW, Schulz-Trieglaff EK, Carassiti D, Gentleman SM, Nicholas R, Roncaroli F, Reynolds R.

Extensive grey matter pathology in the cerebellum in multiple sclerosis is linked to inflammation in the subarachnoid space.

Neuropathol Appl Neurobiol. 2014. doi: 10.1111/nan.12199. [Epub ahead of print]

Multiple Sclerosis (MS) is a progressive inflammatory neurological disease affecting myelin, neurons and glia. Demyelination and neurodegeneration of cortical grey matter contributes to a more severe disease and inflammation of the forebrain meninges associates with pathology of the underlying neocortical grey matter, particularly in deep sulci. We assessed the extent of meningeal inflammation of the cerebellum, another structure with a deeply folded anatomy, to better understand the association between subarachnoid inflammation and grey matter pathology in progressive MS.
METHODS:We examined demyelinating and neuronal pathology in the context of meningeal inflammation in cerebellar tissue blocks from a cohort of 27 progressive MS cases previously characterized on the basis of the absence/ presence of lymphoid-like aggregates in the forebrain meninges, in comparison to 11 non-neurological controls.
RESULTS:Demyelination and meningeal inflammation of the cerebellum was greatest in those cases previously characterised as harbouring lymphoid-like structures in the forebrain regions. Meningeal inflammation was mild to moderate in cerebellar tissue blocks and no lymphoid-like structures were seen. Quantification of meningeal macrophages, CD4+, CD8+ T lymphocytes, B cells and plasma cells revealed that the density of meningeal macrophages associated with microglial activation in the grey matter, and the extent of grey matter demyelination correlated with the density of macrophages and plasma cells in the overlying meninges, and activated microglia of the parenchyma.
CONCLUSIONS:These data suggest that chronic inflammation is widespread throughout the subarachnoid space and contributes to a more 
severe subpial demyelinating pathology in the cerebellum.

Cortical lesions in the grey matter have been linked by some people to the presence of inflammation in the spaces surrounding the brain, notably the presence of B cell structures in the sulci (folds of the brain). This study looked in the cerebellum another folded structure and found the same thing. 

Will it be repeated by other pathologists..based on past record some will and some won't. 

This makes it very difficult to model because there is not sufficient uniform opinion of what is occurring in MS. Pathologists need to get their thinking caps on and get some agreement.