Résumé
Interleukin 10 [IL10] is a key cytokine that is abnormally produced in autoimmune diseases. In this study IL10 was measured in 98 children chosen from the pediatric department, Ain Shams University and Maadi Armed Forces Hospital. Thirty four had rheumatic fever [RF], twelve had systemic lupus erythematosus [SLE], twelve had juvenile rheumatoid arthritis [JRA] and forty healthy age and sex matched controls. Patients with RF were further subcategorized into 17 patients with active RF and 17 patients with past history of RF [PHRF]. IL10 relation to the clinical diagnosis, disease activity and laboratory investigations were assessed. Investigations for RF patients included : ESR, CRP, ASOT, Chest and heart x-ray and echocardiography, while SLE and JRA patients had the following done: CBC, ESR, urine analysis, urinary proteins, renal functions, antinuclear factor, antids DNA, antiSm, anticardiolipin antibodies, complement level and rheumatoid factor IL10 was significantly increased in RF, SLE and JRA patients when compared to the control group [P < 0.01]. SLE patients had the highest levels followed by JRA then RF patients. Patients with serious manifestations as rheumatic carditis and those with SLE associated with organ involvement [central nervous system and or renal affection] showed an increase in the mean IL10 than other patients of the same group. Patients with rheumatic arthritis [known to heal without tissue damage] had normal IL10 levels. On the other hand patients with polyarticular JRA had the highest IL10 levels followed by the systemic onset and pauciarticular types. A positive correlation was present between IL10 values and the duration of the disease in JRA and RF and the number of RF attacks IL10 had also a positive correlation with the disease activity scoring system in SLE but not in JRA. Laboratory investigations didn't correlate with IL10 level in all groups except for antiSm and antids DNA antibodies among SLE patients. These results highlight the involvement of IL10 in the immune dysregulation of RF, SLE and JRA. It increased with enhanced tissue damage. Because the basic immunologic defects in SLE, JRA and RF are different, the role of IL10 in each disease is probably different. Whereas it exaggerates SLE symptoms, it is thought to be beneficial in JRA. The role of IL10 or IL10 antagonists in the treatment of these autoimmune disorders remains to be elucidated