Systemic lupus erythematosus and systemic scleroderma in patients from the aboriginal people and the newcomers of Yakutia under the extreme conditions of the far north.

There is some information on the course of two main forms of large collagenoses-systemic lupus erythematosus (SLE) and systemic scleroderma (SSD) under the conditions of the North of the Asian part of Russia (Yakutia) in this paper. Seventy-nine cases (59 SLE patients and 20 SSD patients) belonging to different ethnic groups were studied. There were 47 patients of Yakutian nationality, among them SLE 38 patients and SSD nine patients. There were 32 patients (SLE-21, and SSD-11) migrant Europeans. It has been proved that the aboriginal people of the North are more subject to SLE and SSD diseases as compared to the migrants. It has also been proved that the greater spreading of the diseases, with the collagen metabolism disturbance in the first ethnic group, including Marfan's syndrome and rheumatoid arthritis may be explained by genetic peculiarities. Some ethnically stipulated differences in clinical manifestations of two large collagenosis were revealed. Thus, during SLE smaller frequency of the skin impairment in the Yakuts (due to natural hyperpigmentations) is connected with the considerable frequency of large joints impairment and more frequent course of SLE similar to rheumatoid variant with typical wrist deformation. One-third SLE and SSD patients of Yakut nationality reveal "overlap-syndrome", which are typical of other collagenoses, the so-called overlap-syndrome. Some industrial factors (dust of silicon dioxide, vibration, hydrocarbon compounds) are the main reason for the diseases among the newcomers migrants of Russian and Ukranian nationality. One case of silico-lupus was revealed.(ABSTRACT TRUNCATED AT 250 WORDS)