Can colchicine response be predicted in familial Mediterranean fever patients?

OBJECTIVES: The aims of this study were to explore whether the demographic and clinical features of paediatric familial Mediterranean fever (FMF) patients with different colchicine response vary or not and to determine whether colchicine response can be predicted in FMF patients.

METHODS: Files of patients who have been on colchicine therapy for at least 6 months were retrospectively evaluated. Patients were divided into two groups: group I included patients with no attacks after colchicine and group II comprised patients with ongoing attacks. Thereafter group II was further divided into two groups according to the reduction rate of attack frequency: group IIA (>50%) and group IIB (≤50%).

RESULTS: The study group comprised 221 FMF patients (116 females, 105 males). There were 131 patients in group I and 90 patients in group II (54 in group IIA and 36 in group IIB). Leg pain and M694V homozygosity were more frequent in group II (P < 0.05). Final colchicine doses, disease severity scores and number of patients with elevated acute phase reactant levels (attack-free period) were significantly higher and colchicine compliance was lower in group II when compared with group I (P < 0.05). Erysipelas-like erythema (ELE), leg pain and protracted arthritis/protracted febrile myalgia/vasculitis were more frequently detected in group IIB (P < 0.05).

CONCLUSION: Colchicine response is excellent in the majority of FMF patients, however, colchicine unresponsiveness cannot be predicted easily at onset. More rarely encountered clinical findings such as ELE, leg pain and protracted complaints and M694V homozygosity may be a clue for less colchicine response.