Background: Fluoroquinolone antibiotics are commonly used to treat infections and are prescribed by general practitioners, medical specialists and surgeons. Tendon injury has been associated with the use of these medications but the risk associated with newer fluoroquinolones has not been established.
Objectives: The aim of this systematic review was to evaluate the evidence from observational studies to determine the strength of the association between fluoroquinolone use and tendinopathy, and to identify risk factors for this complication.
Methods: We searched MEDLINE, EMBASE and the Cochrane Collaboration from inception through May 2013 to identify observational studies focused on tendon injury and fluoroquinolones. Studies with original data were selected for inclusion following the PRISMA guidelines. Of the 560 abstracts screened, 16 relevant studies were independently rated by three authors (WW, AS, DC) using the Newcastle-Ottawa Quality Assessment Scale, and assigned a quality score out of 9. High-quality studies (i.e. scored 4.5 or higher) are summarized in detail in this article. Data were independently extracted by two authors (WW, AS).
Results: Overall, 16 studies were included in our study. Eight were deemed to be of high quality and five specifically evaluated Achilles tendon rupture. In addition, three studies examined Achilles tendinitis, and three included tendon disorders (including any tendon rupture) as an outcome. Results from these studies suggest that individuals exposed to fluoroquinolones are at increased risk for Achilles tendon rupture, particularly within the first month following exposure to the drug (odds ratios ranged from 1.1 to 7.1). One study showed an increased risk of tendon rupture in those over 60 years of age. Five studies stated that individuals taking fluoroquinolones and oral corticosteroids are at increased risk for tendon injury compared with those taking fluoroquinolones alone. Four studies examined the differential effect of a limited number of fluoroquinolones. Ofloxacin had the highest risk of tendon injury in three of the studies.
Limitations: Included studies are observational in nature and rely on self-report, which may lead to misclassification or underestimation of tendon injury.
Conclusions: Observational studies showed an increased risk of tendon injury, including tendon rupture and tendinitis, with exposure to fluoroquinolone antibiotic therapy. Although this complication appears to be rare, concomitant corticosteroids increase the risk for tendon injury, which varies depending on the fluoroquinolone used.