Potential quinolone-induced cartilage toxicity in children

Drug-Induced Musculoskeletal Disorders

Drug-induced musculoskeletal disorders represent a broad clinical spectrum, from asymptomatic biological abnormalities to severe and even life-threatening diseases. Since an increasing number of drugs have been implicated in inducing rheumatic symptoms and/or syndromes, this review is not meant to be exhaustive, bearing in mind that the development of any musculoskeletal disorder should be considered as possibly related to a medication. The purpose of this article is to provide an overview of the more frequent drug-induced musculoskeletal disorders. These include: (i) arthralgias and arthropathies, including chondropathies and inflammatory arthritis; (ii) connective tissue diseases, especially lupus-like syndromes; (iii) periarticular disorders, including tendinopathies, enthesopathies and frozen shoulder; (iii) bone diseases, such as osteoporosis, osteomalacia and osteonecrosis; and (iv) myopathies. Although virtually all drug classes may induce musculoskeletal disorders, a significant part of them are related to corticosteroids, vaccines, antibacterials and lipid-lowering agents. Knowledge of drug-induced musculoskeletal disorders avoids carrying out unnecessary investigations, and allows optimal management of the patients, i.e. early discontinuation of the offending agent, adequate treatment monitoring and/or intervention with appropriate preventive actions.

Veterinary pharmacovigilance. Part 6. Predictability of adverse reactions in animals from laboratory toxicology studies

Toxicological studies are conducted on constituents of veterinary medicinal products for a number of reasons. Aside from being a requirement of legislation, they are carried out for predictive purposes in the assessment of user safety or for the determination of consumer safety, for example, in the elaboration of maximum residue limits or tolerances. Alternatively, the results of toxicology studies may be available as they have been generated for registration of the drug for human medicinal purposes. This paper examines if the results of such studies have any predictive value for adverse reactions, which might occur during clinical use in animals. A number of adverse reactions, notably the Type A (toxicology or pharmacology dependent) should be predictable from these laboratory studies. However, as with human pharmaceutical products, they have less utility in predicting Type-B reactions (idiosyncratic in nature).

Destruction and loss of bronchial cartilage in cystic fibrosis

We studied by means of serial sections of intact isolated bronchi, the distribution and morphology of bronchial cartilage in lobar and segmental airways of 6 patients with cystic fibrosis (CF). Findings were compared to those of 4 young adults without CF who served as controls. Compared to the controls, cartilage in CF airways extended for a shorter absolute distance along the bronchial tree and disappeared at a more proximal branching level. Loss of cartilage appeared to correlate with the severity of bronchiectasis. In proximal airways chronic inflammation, destruction and fibrous replacement of cartilage preceded its disappearance. Immunohistochemical staining indicated that cells of monocyte/macrophage lineage (CD68, MAC387 positive) were most closely associated with chondrolysis. Dystrophic calcification and ossification were more commonly seen in CF bronchi and dystrophic calcification was present even in the lobar branches. Destruction of bronchial cartilage is the result of sustained bronchial infection and chronic inflammation and is an additional contributory factor to bronchiectasis and airway instability in patients with CF.

Sequential ciprofloxacin therapy in pediatric cystic fibrosis: comparative study vs. ceftazidime/tobramycin in the treatment of acute pulmonary exacerbations. The Cystic Fibrosis Study Group

BACKGROUND

Cystic fibrosis patients have chronic bacterial infections of the respiratory tract, most commonly Pseudomonas aeruginosa. Although controversial, administration of antibiotic therapy during acute pulmonary exacerbations is standard practice. Fluoroquinolones are currently not indicated for use in young children because of the observation of arthropathy and damage to growing cartilage in beagle puppies. Because of its activity against P. aeruginosa and excellent oral bioavailability, ciprofloxacin offers a unique therapeutic alternative for this patient population.

OBJECTIVE

This prospective, randomized, double blind study compared the efficacy and safety of sequential intravenous/oral ciprofloxacin vs. ceftazidime/tobramycin in hospitalized pediatric cystic fibrosis patients with an acute pulmonary exacerbation associated with P. aeruginosa infection.

METHODS

One hundred thirty patients (ages 5 to 17 years) were randomized to receive either i.v. ciprofloxacin 10 mg/kg every 8 h for 7 days followed by oral ciprofloxacin 20 mg/kg every 12 h for a minimum of 3 days or i.v. ceftazidime 50 mg/kg every 8 h plus i.v. tobramycin 3 mg/kg every 8 h for a minimum of 10 days. Clinical, bacteriologic and safety responses were assessed throughout the study.

RESULTS

All 84 patients (median age, 11 years; range, 5 to 17 years) valid for efficacy in both treatment groups demonstrated clinical improvement. Five patients experienced clinical relapses (3 ciprofloxacin, 2 ceftazidime/tobramycin) by the 2- to 4-week follow-up. Intent-to-treat analysis demonstrated similar clinical findings between the two treatment groups at both the end of therapy and follow-up. Clinical improvement correlated with improvement in pulmonary function studies and the acute clinical scoring system but not with bacteriologic eradication of Pseudomonas. DNA profiles demonstrated that irrespective of colony morphology, usually one clonal strain was associated with each patient's pulmonary exacerbation. Treatment-associated musculoskeletal events occurred with equal frequency (22% vs. 21%) in both study drug groups (n = 129), and arthralgias were within the range of rates for cystic fibrosis arthropathy. None of these events required study drug discontinuation.

CONCLUSION

Sequential i.v./oral ciprofloxacin monotherapy offers a safe and efficacious alternative to standard parenteral therapy for acute pulmonary exacerbations in pediatric cystic fibrosis patients.