Abstract

PIP: The disease multiple sclerosis (MS) presents problems to the morbid anatomist, the histopathologist, the chemical pathologist, microbiologist, immunologist, and the clinician. The pathology is characterized by patches of demyelination scattered throughout the central nervous system which in the later stages undergo gliosis. The earliest lesions appear to be represented by the penetration of lymphocytes from the blood stream into the brain. At this time there is no diagnostic test, but the majority of patients have an increased level of IgG in the CSF and the presence of oligoclonal bands supports the diagnosis. There is nothing truly pathognomonic in the CSF findings. MS is one of the commonest causes of crippling diseases of adults and is most likely the commonest disease of the central nervous system in adults of 20-50 years. The age of onset peaks at about 30-40 years and is slightly earlier in females than in males. 10% of MS patients have another member of their family affected, but the disease is familial not hereditary. Recent surveys have shown that patients with MS have higher frequencies of some of the histocompatibility genes than have controls. The disease is more prevalent in the northern hemisphere. There is no evidence that the disease occurs in epidemics. An attempt has been made to put together the various factors which may be involved in the etiology of MS. It appears that the geographical distribution of MS is related to the consumption of animal fats which are deficient in unsaturated fatty acids. Consequently, MS is common in Western Europe and North America where the consumption of animal fat is high and uncommon in Asia, Southern Europe, Black Africa, and Japan. There also appears to be a negative correlation between the geographical distribution of MS and that of breastfeeding; areas where breastfeeding is common are also associated with a low intake of animal fats. The question that arises is whether it could be possible that breastfeeding is associated with the development of normal myelin which is not vulnerable to the initiating trauma of MS, while those fed on cow's milk have an inferior type of myelin which is susceptible to damage. This possible explanation will be tested.