[Pathogenesis of multiple sclerosis. Work-hypotheses and experimental data]

In spite of a history of more than 100 years, the pathoaetiology of multiple sclerosis is still unknown today. Research is based on three working hypotheses, i.e. on an immunopathological disease origin, on the conception that MS, as an infectious disease, is caused by a specific pathogen (slow virus infection) and on the assumption of a disturbance of basal metabolism or utilisation. The present position of the scientific foundation of the working hypotheses is presented in detail and supplemented by the results of our own investigations. Of particular interest are the geomedical studies which show that MS occurs more frequently in temperate climatic regions. In Europe, a latitude of 46 degrees forms a conspicuous boundary; in the USA this boundary is found at 38 degrees. North of this line there is a morbidity rate of 30 to 60 patients per 100 000 inhabitants, while south of it 15 cases at most per 100 000 inhibitants are found. Asia, especially in China and Japan, and tropical countries, where Multiple Sclerosis is practically unknown in the native populations, are exceptions. The observation that immigrants from areas with a low MS incidence into regions with a high risk of MS fall ill with the disease after years remains also unexplained. These peculiarities have given rise to the consideration whether there is a still unknown factor in the soil of high-risk areas or a specific pathogenic spectrum. In this connection, the question is also discussed whether the risk of MS in northern countries is associated with the excessive consumption of animal fat. The possible therapeutic and prophylactic significance of unsaturated fatty acids is emphasized. Our own results with the Schilling-test, determination of gastric acids, rubella titres in serum and cerebrospinal fluid, the immunofluorescence test of the serum and CSF, determination of tissue antigens (HLA) in families with multiple incidence of Multiple Sclerosis are discussed. On evaluation of a large series of patients, it is striking that Multiple Sclerosis and juvenile diabetes seem to be mutually exclusive (Schrader). Likewise, in MS statistics no other immunopathologic disease such as rheumatic diseases or bronchial asthma was found. Interestingly, also in 400 MS patients examined, hyperuricaemia or gout, which are widespread among the populace, were not found in a single case.