According to a study from Regina E. Abotsi and colleagues, resistance to azithromycin (AZM) and other antibiotics such as tetracyclines and lincosamides is a pressing concern in the long-term use of AZM for treating patients with chronic lung diseases (CLD). Abotsi and collaborators evaluated the effect of a 48-week AZM regimen on the carriage and antibiotic resistance of common respiratory bacteria among children with human immunodeficiency virus (HIV)-associated CLD. Their study, published in ERJ Open Research, reported higher AZM resistance in several bacterial species.

Patients with HIV-associated CLD were randomized to receive either weekly AZM or a placebo for 48 weeks. Follow-up was performed until 72 weeks post-intervention. The researchers collected nasopharyngeal (NP) swabs and sputa samples at enrollment, 48 weeks, and 72 weeks to assess the primary outcomes of prevalence and antibiotic resistance of Streptococcus pneumoniae (SP), Staphylococcus aureus (SA), Haemophilus influenzae (HI) and Moraxella catarrhalis (MC). Carriage and resistance comparisons were performed with mixed-effects logistic regression and Fisher’s exact test.

Among the 347 patients (AZM = 174; placebo = 173), the study’s authors observed that NP carriage was significantly lower in the AZM arm compared to the placebo arm for SP (18% vs. 41%; p <0.001), HI (7% vs. 16%; p = 0.01), and MC (4% vs. 11%; p = 0.02). However, SP resistance to AZM or tetracycline was higher in the AZM group (p <0.0001). Lastly, carriage of SA resistant to AZM, tetracycline, and clindamycin was significantly higher in the AZM arm and persisted through the 72-week follow-up.

The study’s authors added that similar carriage and resistance results were observed in the sputa samples. Ultimately, their findings led them to conclude that “the persistence of antibiotic resistance and its clinical relevance for future infectious episodes requiring treatment needs further investigation.”

Source: ERJ Open Research

https://doi.org/10.1183/23120541.00491-2021