Background: Familial Mediterranean Fever (FMF) is a systemic relapsing autoinflammatory disorder. Adenosine deaminase (ADA) is an enzyme widely distribute in tissues and body fluids. Circulating levels of ADA have been shown to increase in several inflammatory conditions. This study was designed to evaluate the serum ADA in patients with FMF during acute attacks and attack-free periods.
Methods: The study groups comprised 23 FMF patients in attack-free period (male/female: 11/12), 30 FMF patients in attack period (male/female: 11/19) and 20 healthy control (male/female:10/10). The groups were similar for age, gender and disease duration.
Results: The mean age of FMF patients in attack-free period, patient with acute attack were 34.3+/-11.7 and 29.4+/-11.1 respectively. The disease durations were 13.1+/-10.2 and 8.2+/-7.6 years for patients in attack-free periods and patients with acute FMF attack, respectively. Patients with acute attack had significantly higher ADA levels than both patients with attack-free periods and healthy controls (for each, p<0.001).
Conclusion: In this study we demonstrated that FMF patients with acute attacks had higher serum ADA levels than attack-free periods and healthy controls. It is likely that ADA may have a role in the cytokine network of the inflammatory cascade of FMF. Also, elevated ADA levels may be a part of the activated Th1 response in the disease. ADA may be used as a supportive marker to differentiate FMF attacks from attack-free periods. Further larger-scale studies are needed to support this result.