The best questions often stem from the inquisitive learner. As educators, we love—and are always humbled—by those moments when we get to say, “I don’t know.” For some of these questions, some may already know the answers. For others, some may never have thought to ask the question. For all, questions, comments, concerns, and critiques are encouraged. Welcome to the Kids Korner.

Question #1: What’s the deal with fluoroquinolones and bones/tendons in children?

Fluoroquinolones were spin-offs of antimalarial drugs and were approved for use in children in the 1960s. According to reviews by Burkhardt et al and Patel et al, quinolone-induced arthropathy changes have been seen in nearly all laboratory animals studied, particularly in weight-bearing joints and only in juvenile animals.^1,2 There are a number of case reports referenced by these authors that demonstrate that these joint changes can occur in children and adolescents. In these cases, joint complaints resolved with drug cessation. Also, the majority of these cases were cystic fibrosis patients who had received prolonged courses of fluoroquinolones.

In regard to pediatric findings, a study by Hampel et al retrospectively looked at 1,795 patients younger than 17 years of age and reported adverse events.³ The incidence of adverse events was 10.9 percent. While most adverse events were nausea, vomiting, and diarrhea, only 1.5 percent of the total population developed arthralgia. The median duration of ciprofloxacin treatment was 23 days. While this study was sponsored by Bayer—the maker of Cipro—these rates do appear to be consistent with other studies.²

In certain clinical scenarios, the use of a fluoroquinolone in a child may be necessary and appropriate, and the practitioner shouldn’t live in terror of destroying a child’s hopes of playing professional sports.

There are also prospective studies on this topic. A multicenter observational study by Chalumeau et al looked at potential adverse events between fluoroquinolone-exposed and control subjects (n=276 exposed; n=249 control).⁴ Patients were younger than 19 years of age, and the incidence of musculoskeletal adverse events was low (3.8 percent) but still higher than the incidence previously reported in adults (0.01 percent to 0.2 percent). All the bone/joint adverse events were transient. Another prospective study by Noel et al was a nonblinded, multicenter, randomized study of 2,523 children that looked at the association of levofloxacin with four different joint/bone complaints: tendinopathy, arthritis, arthralgia, and gait abnormality.⁵ Joint/bone complaints in weight-bearing joints were present in 2.9 percent of levofloxacin-exposed patients versus 1.6 percent of control patients. There were no abnormalities on computed tomography and magnetic resonance imaging scans of patients evaluated for these bone/joint complaints. All symptoms resolved with cessation of the drug.

Summary

Studies suggest a small—but statistically significant—increase in arthropathy/arthritis in children who take fluoroquinolones. It is predominately in weight-bearing joints but also transient. In certain clinical scenarios, the use of a fluoroquinolone in a child may be necessary and appropriate, and the practitioner shouldn’t live in terror of destroying a child’s hopes of playing professional sports.