Hypercoagulability: interaction between inflammation and coagulation in familial Mediterranean fever

Abstract
Familial Mediterranean fever (FMF) patients in clinical remission are reported to have increased baseline inflammation. Normal function of the natural anticoagulant pathways is particularly needed in diminishing inflammatory responses. In the presence of subclinical inflammation, natural anticoagulant response may be exaggerated. We aimed to observe the anticoagulant–procoagulant status in attack-free FMF patients. Twenty-seven FMF patients diagnosed in accordance with Tel-Hashomer criteria, and 26 healthy controls were included. All patients were attack-free under regular colchicine treatment. Amyloidosis, autoimmunity, accompanying liver and renal disease, and vasculitis were excluded. Predisposing factors for thrombosis were not present. Acute phase reactants (APRs), anticardiolipin antibody positivity, prothrombin time (PT), activated prothrombin time, thrombin time (TT) and d-dimer, protein C activity, activated protein C resistance, free protein S, antithrombin, lupus anticoagulant, human prothrombin fragment F 1 + 2, and human thrombin/antithrombin III complex were analyzed for all subjects. APRs were comparable with controls. Autoimmune markers were negative in all. Anti-streptolysin titers were significantly different than the control group. PT, TT, protein C activity, and F 1 + 2 levels were significantly different from those of healthy controls. Shortened PT and TT, decreased protein C activity vs increased levels of F 1 + 2 suggested a hypercoagulable state in our patients. The hypercoagulable state detected in FMF patients suggests that screening with abnormal coagulation tests may be beneficial for tracing the future consequences of subclinical inflammation in these patients. Studies covering larger groups of patients are needed to verify the currently observed hypercoagulable status in FMF.