High Rates of Macrolide Resistance Detected in Acne-Causing Bacteria

The prevalence of macrolide resistance among Cutibacterium acnes (C. acnes) strains is higher than previously reported, study data published in Frontiers in Public Health suggests. Screening for macrolide resistance in patients with acne may reduce macrolide misuse and improve clinical response, the researchers wrote.

Macrolides have been a front-line acne treatment for more than 50 years. However, the growing prevalence of antibiotic resistant Propionibacterium acnes has made appropriate macrolide use more difficult. To better guide acne treatment, investigators developed the Cutibacterium acnes quantitative PCR (qPCR)-based antibiotics resistance assay (ACQUIRE). ACQUIRE is capable of detecting the presence of macrolide-resistant C. acnes using samples from patient’s acne lesions. To test the utility of this assay, investigators conducted a cross-sectional observational study of patients treated for acne at participating dermatology centers in Changsha, China from 2017 to 2020. Eligible patients were 12 to 50 years of age and had moderate to severe acne per the global acne grading system.

Specimens were obtained from a total of 915 patients with acne, of whom 525 were women and 390 were men. Mean age at testing was 24.1 ± 5.7 years. Per ACQUIRE results, the C. acnes 23S recombinant DNA (rDNA) point mutation rate was much higher than previously reported, with 52% of patients carrying at least 1 mutation. Macrolide-resistant genotypes were detected in 75.5% of tested samples. The most frequently detected macrolide-resistant determinant was the ermX gene, present in 53% patients. Results from this study suggest to the researchers that more prevalent 23S rDNA mutations have driven a higher rate of macrolide resistance in C. acnes.

As the investigators explained, the ACQUIRE assay enables providers to test for macrolide resistance, thus limiting the use of ineffective antibiotics. However, large-scale randomized clinical trials are necessary to prove the efficacy of ACQUIRE in guiding acne treatment.

“As a supplement to the current acne treatment algorithm, ACQUIRE can be used whenever a macrolide agent is intended to be prescribed, including topical and oral agents, and leave the rest of treatment options uninfluenced, which made it easy to integrate ACQUIRE into current treatment modalities and guidelines,” investigators wrote. “By eliminating antibiotic misuse, ACQUIRE can make acne treatment more effective with less cost and shortened course of the disease, representing an opportunity to improve the quality of care.”

Reference

Zhang J, Yu F, Fu K, et al. C. acnes qPCR-based antibiotics resistance assay (ACQUIRE) reveals widespread macrolide resistance in acne patients and can eliminate macrolide misuse in acne treatment. Front Public Health. Published online March 18, 2022. doi:10.3389/fpubh.2022.787299