A small group of dermatology researchers suggest the rising incidence of antibiotic resistance represents an emergent need to restrict the unapproved use of azithromycin in patients with acne, in a letter to the editor published in the Journal of the European Academy of Dermatology and Venereology.
Currently, azithromycin is approved for acne only in Japan. But studies have consistently shown that rates of resistance to azithromycin are generally similar to rates of resistance to erythromycin, an antibiotic agent that may be the driving force for resistance in acne, it was noted.
In contrast, the widescale use of topical clindamycin in Greece and Spain may have been the contributor to high levels of antibiotic resistance in these regions. Rates of resistance to azithromycin vary in range, including low prevalence rates in Egypt (5.1%) and Australia (8.8%) and high prevalence rates in India (100%) and Mexico (82%).
Several mutations have been associated with resistance to azithromycin, including the 23S rRNA,2058G, Erm(X) coding mutation. Other studies suggest long-term use of macrolides like azithromycin can result in expression of 23S rRNA mutations A2058G, A2059G, and C2611G, the investigators pointed out. This expression is enhanced with the use of clindamycin. According to the study authors, these mutations may explain why long-term use of these agents increases the frequency of resistant mutants as well as clinical failures in patients with acne.
Approved indications for azithromycin include upper and lower respiratory tract infections, tick-borne infections, cat-scratch disease, toxoplasmosis, and urethritis and cervicitis, among several others. As such, the study authors argue that the off-label use of azithromycin and the potential subsequent resistance to the drug could make the management of other disorders more difficult.
The researchers add that the lack of azithromycin’s superiority over cyclines, the proven associated mutations, the drug’s use in other medically important indications, as well as “the documented clinical failures are sufficient reasons to restrict the misuse of this drug except in patients who cannot use cyclines,” such as “pregnant women or children <8 years of age.”
Reference
Sardana K, Mathachan SR, Gupta T. Antibiotic resistance in acne an emergent need to recognize resistance to azithromycin and restrict its unapproved use in acne vulgaris. Published online December 22, 2020. J Eur Acad Dermatol Venereol. doi:10.1111/jdv.17099