Familial Mediterranean fever is a hereditary disease, characterized by recurrent episodes of inflammation. Colchicine, the mainstay of therapy, is administered continuously to all diagnosed FMF patients. Drug-drug interaction between colchicine and clarithromycin, resulting in colchicine intoxication, has been noted, mainly in association with gout and pneumonia. In FMF, this adverse event has been scarcely described. We present and characterize six patients with clarithromycin-related colchicine intoxication, aiming mainly at characterizing the FMF-specific features of this event. This study is a retrospective analysis, based on clinical and hospital records of all FMF patients admitted to one hospital during 2002-2015, for colchicine intoxication, precipitated by consumption of clarithromycin. All six patients were women who received colchicine for FMF, and clarithromycin for Helicobacter pylori (HBP) gastric infection. Their daily dosages of colchicine ranged from 1.5 to 2.5 mg. Two had mild FMF, two moderate and two severe diseases. Colchicine intoxication occurred despite intact kidney function and was characterized by abdominal pain, diarrhea, weakness, rhabdomyolysis, hepatitis, kidney impairment and bone marrow injury. It is concluded that clarithromycin-induced colchicine intoxication is a hazard in FMF. It occurs despite normal kidney function and standard colchicine dose and is associated with female sex and moderate to severe FMF.
Keywords: Clarithromycin; Colchicine; Drug toxicity; Drug–drug interaction; Familial Mediterranean fever; Helicobacter pylori.