Purpose of the study. To study the relationship between the serum level of interleukin-4 (IL-4) and visceral pathology, the nature of the course and clinical forms of SS. Materials and methods. IL-4 was determined in the sera of 60 patients with SS by indirect enzyme-linked immunosorbent assay. Results. The level of IL-4 in the range of 10-1000 pg/ml was detected in 18 out of 60 patients with SS (30%). Distinctive features of this group of patients were a shorter duration of the disease, progression of skin fibrosis and visceral pathology by the time of the examination, and a tendency towards a higher incidence of pulmonary fibrosis

Interleukin-4, T lymphocytes, Fibrosis, Activity, Systemic Scleroderma.