CliniCal FoCus

January 2015 PraCTICaL DErMaTOLOGy 47

Antibiotic resistance has quickly developed into one of the most important global problems in the practice of medicine. According to a report from the Centers for Disease Control and Prevention in 2013, an esti-

mated two million illnesses and 23,000 deaths developed from infections with resistant bacteria.1 Antibiotic resistance has been prioritized by the science ministers of the G8 countries and deemed by the World Health Organization (WHO) as a rapidly evolving health issue extending far beyond the human health sector” that requires “urgent action... at the highest political level.”2,3 This article will explore the global implications for antibiotic resistance, assess the next steps, and examine the relevance for our own specialty.

Running the numbeRs on Antibiotics

Since the first observations in 1979, data collected from acne patients in several countries has revealed a growing emergence of antibiotic-resistant isolates of P. acnes. The worldwide preva-lence rate has been reported to increase from 20 percent 1978 to 62 percent in 1996.4-6 Erythromycin is particularly problem-atic in treating acne, as most P. acnes bacteria demonstrate high levels of resistance.11 While resistance to various topical antibiotics is a global phenomenon, it is perhaps most note-worthy in the United States.5

In 2012, healthcare providers prescribed more than 260 million courses of antibiotics in 2012.7 Of these prescriptions, dermatologists prescribed 9.6 million of these courses. While dermatologists represent only one percent of all health care professionals in the United States, they prescribe almost five percent of antibiotics. Oral and topical antibiotics account for 54 percent of acne prescriptions in dermatology. If you include fixed dose combination topics drugs, 66 percent of all derma-

tology prescriptions written for acne contain an antibiotic. In 2012, tetracyclines (including doxycycline and minocycline) account for 70 percent of oral antibiotics prescriptions, fol-lowed by cephalosporins, which accounted for 11 percent.

Antibiotics in DeRmAtologyAntibiotic monotherapy is not recommended to treat acne

because of the risk of developing resistant bacteria. Application of topical antibiotics has been shown to promote resistant flora in skin of treated site12,13 and oral antibiotics affects flora on all body sites.14,15 Moreover, antibiotic monotherapy is not as effective as combination therapy with other agents, such as benzoyl peroxide. One meta-analysis found only an incre-mental benefit in adding clindamycin to benzoyl peroxide (BPO), with no benefit in within the first two to four weeks and marginal benefit after 10-12 weeks.8 Moreover, one study looking at mild to moderate acne demonstrated similar effi-cacy between oral doxycycline 100 mg daily and BPO 5%.9 In another study evaluating five different acne regimens, topical BPO and a combination BPO and erythromycin were found to have similar efficacy to oral antibiotics.10

While antibiotic resistant P. acnes is a known phenomenon, the question that arises is whether this is clinically meaningful. At this point, we do not know. P. acnes is a low risk bug that can be considered “antisocial.” As such, the risk of spreading resistance from P. acnes to other organisms is low.

Collateral damage to commensal skin flora is the major issue with antibiotic monotherapy. Both correct and incorrect use of antibiotics for the treatment of acne can promote antibac-terial resistance.18 In other words, whether the antibiotic is being prescribed for an anti-microbial or anti-inflammatory reason, their use promotes resistance among even normal skin

As antibiotic resistance increasingly poses significant challenges, dermatologists should

make necessary adjustments in the treatment of acne.

by JoshuA ZeichneR, mD

addressing antibiotic resistance in acne regimens