Fluoroquinolone-associated Tendinopathy

The fluoroquinolones (FQs) are used to treat a wide rangeof infections because of their excellent gastrointestinal absorption, superior tissue penetration and broad-spectrum activity.Recently, FQ-associated tendinopathy and tendon rupture havebeen reported, especially in the elderly and patients with diabetes and renal failure. However, these adverse effects do notappear to be widely known among physicians. Because of thefrequent use of FQs in clinical practice, physicians should beaware of their potential for severe disability from tendon rupture. Achilles tendinopathy or rupture is among the most serious side effects associated with FQ use, with reports markedlyinc r e a s ing, e spe c i a l ly wi th the us e of c iprof loxa c in. Thehistopathologic findings include degenerative lesions, fissures,interstitial edema without cellular infiltration, necrosis andneovascularization. There are possible molecular mechanismsaccounting for FQ-associated tendinopathy. First, ciprofloxacin mediates inhibition of cellproliferation and G2/M cell cycle arrest in tendon cells by down-regulation of cyclin B andcyclin-dependent kinase 1. Second, ciprofloxacin inhibits the spead and migration of tenocytes by down-regulation of focal adhesion kinase phosphorylation. Third, ciprofloxacinenhances the enzymatic activity of matrix metalloproteinase-2 with degradation of type Icollagen. Management of FQ-associated tendinopathy includes immediate discontinuation ofFQs, rest, non-steroidal anti-inflammatory drugs, physical modalities and eccentric strengthening exercise. Tendon rupture may require surgical intervention.