Levels of interleukin-6 (IL-6) and its soluble receptor (sIL-6R) in familial Mediterranean fever (FMF) patients and their first degree relatives

• Published in: Clinical and experimental rheumatology 2004-07, Vol.22 (4 Suppl 34), p.S34-S36
• Main Authors: Oktem, S, Yavuzsen, T U, Sengül, B, Akhunlar, H, Akar, S, Tunca, M
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Enzyme-Linked Immunosorbent Assay; Familial Mediterranean Fever - genetics; Familial Mediterranean Fever - immunology; Female; Genetic Predisposition to Disease; Heterozygote; Humans; Interleukin-6 - blood; Male; Middle Aged; Nuclear Family; Receptors, Interleukin-6 - blood
• ISSN: 0392-856X

Familial Mediterranean Fever (FMF) is a hereditary disease characterized by recurrent inflammatory attacks. A subclinical inflammation may persist in periods between the attacks and heterozygotes may have higher than normal levels of acute phase proteins. We investigated the levels of interleukin-6 (IL-6) and its soluble receptor (sIL-6R) in FMF patients and their obligatory carrier relatives. Serum levels of IL-6 and sIL-6R were measured during acute attacks (n = 18) and in attack-free FMF patients (n = 26), obligatory carriers of FMF (n = 17) and normal controls (n = 11). The median levels of IL-6 were significantly higher (45.71 pg/ mL, p = 0.001) during acute attacks of FMF only, and were normal (0.01 pg/ mL) in the other groups studied. There was no statistically significant difference in the median sIL-6R values between any of the groups (p = 0.22). IL-6 was extremely elevated during FMF attacks but could not detect hypothetical "subclinical" inflammation during attack-free intervals or in the heterozygote relatives of patients. Serum levels of sIL-6R were comparable in all four groups.