Topical antibiotic monotherapy prescribing practices in acne vulgaris

Scientific Rationale and Clinical Basis for Clindamycin Use in the Treatment of Dermatologic Disease

Clindamycin is a highly effective antibiotic of the lincosamide class. It has been widely used for decades to treat a range of skin and soft tissue infections in dermatology and medicine. Clindamycin is commonly prescribed for acne vulgaris, with current practice standards utilizing fixed-combination topicals containing clindamycin that prevent Cutibacterium acnes growth and reduce inflammation associated with acne lesion formation. Certain clinical presentations of folliculitis, rosacea, staphylococcal infections, and hidradenitis suppurativa are also responsive to clindamycin, demonstrating its suitability and versatility as a treatment option. This review describes the use of clindamycin in dermatological practice, the mechanism of protein synthesis inhibition by clindamycin at the level of the bacterial ribosome, and clindamycin's anti-inflammatory properties with a focus on its ability to ameliorate inflammation in acne. A comparison of the dermatologic indications for similarly utilized antibiotics, like the tetracycline class antibiotics, is also presented. Finally, this review addresses both the trends and mechanisms for clindamycin and antibiotic resistance, as well as the current clinical evidence in support of the continued, targeted use of clindamycin in dermatology.

Comparison of dermatologists and family physicians in terms of prescribing antibiotics for the treatment of acne vulgaris

Acne vulgaris (AV) is a common skin disease that is treated both with dermatologists and family physicians (FPs) with different strategies. To assess the antibiotics that are frequently preferred in AV treatment, and the differences between the FPs and dermatologists in treatment were investigated. The physicians were informed about the study, and sent over the internet a multiple-choice questionnaire that consists of 29 questions in total. Afterwards, the answers provided were compared. 201 dermatologists and 147 FPs participated in the study. Dermatologists were found to have preferred topical erythromycin, nadifloxacin, clindamycin, and tetracycline, and systematically doxycycline and azithromycin in adult patients, whereas the FPs were found to have preferred mupirocin, fusidic acid (FA), and oxytetracycline, and systematically tetracycline. Dermatologists were found to have recommended topical clindamycin and erythromycin in pregnant/breastfeeding AV patients, whereas the FPs were found to have recommended FA. Dermatologists were found to have continued the antibiotics for 8 to 12 weeks, whereas the FPs were found to have continued for 1 to 4 weeks. The dermatologists preferred systemic antibiotics in cases with back involvement, moderate to severe AV, and that the FPs preferred them in severe AV. The dermatologists considered that the use of antibiotics alone or long-term were important factors causing antibiotic resistance. There were significant differences between the approaches of dermatologists and FPs to AV treatment. FPs were found to have insufficient information about prevention of antibiotic resistance. Therefore, we think that the continuous training of FPs on dermatology will be beneficial.

Female type of adult acne: Physiological and psychological considerations and management

Today we see more cases of acne after adolescence, with a greater prevalence in females than males. Adult female acne has a distinct clinical presentation and is associated with a number of specific pathophysiological features and gender-specific triggers. The psychological impact of acne is generally significant and largely underestimated; stress during professional and private life, anxiety and sleep quality, in particular, have a reciprocal relationship with disease susceptibility and severity. It is essential to compare with males. Acne in females often causes greater distress in adults than in adolescents. The impact of disease may therefore be greater for female patients, triggering higher levels of psychosocial anguish and increasing the likelihood of sequelae such as skin picking and the risks of cutaneous superinfection, scarring and PIH and acne recurrence. The management of adult female acne should encompass not just medical treatment of the symptoms, but also a comprehensive, holistic approach to the patient as a whole, her individual lifestyle factors and the impact of acne on her quality of life. Future management of this disease should aim to improve patient adherence to therapy and to develop validated outcomes of treatment regarding overall skin appearance and quality of life.

The antimicrobial effect of CEN1HC-Br against Propionibacterium acnes and its therapeutic and anti-inflammatory effects on acne vulgaris

Propionibacterium acnes is a commensal bacterium, which is involved in acne inflammation. An antimicrobial peptide named CEN1HC-Br, which was isolated and characterized form the green sea urchin, has been shown to possess broad-spectrum antibacterial activity. Little is known concerning the potential effects of its antibacterial and anti-inflammatory properties against P. acnes. To examine the potency of CEN1HC-Br in acne treatment, we conducted experiments to analyze the antibacterial and anti-inflammatory activities of CEN1HC-Br both in vitro and in vivo. The antimicrobial activity of CEN1HC-Br was evaluated by minimal inhibitory concentration (MIC) assays using the broth dilution method. To elucidate the in vitro anti-inflammatory effect, HaCaT cells and human monocytes were treated with different concentration of CEN1HC-Br after stimulation by P. acnes. The expression of TLR2 and the secretion of the pro-inflammatory cytokines IL-6, IL-8, IL-1β, TNF-α, IL-12, respectively, were measured by enzyme immunoassays. An evaluation of P. acnes-induced ear edema in rat ear was conducted to compare the in vivo antibacterial and anti-inflammatory effect of CEN1HC-Br, the expression of IL-8, TNF-α, MMP-2 and TLR2 was evaluated by immunohistochemistry and real time-PCR. CEN1HC-Br showed stronger antimicrobial activity against P. acnes than clindamycin. CEN1HC-Br significantly reduced the expression of interleukin IL-12p40, IL-6, IL-1β, TNF-α and TLR2 in monocytes, but they were not influenced by clindamycin. Both CEN1HC-Br and Clindamycin attenuated P. acnes-induced ear swelling in rat along with pro-inflammatory cytokines IL-8, TNF-α, MMP-2 and TLR2. Our data demonstrates that CEN1HC-Br is bactericidal against P. acnes and that it has an anti-inflammatory effect on monocytes. The anti-inflammatory effect may partially occur through TLR2 down-regulation, triggering an innate immune response and the inhibition of pro-inflammatory cytokines.

Filling in Pediatric Acne Practice Gaps: A Prospective Multicenter Study of Case-Based Education

PURPOSE

Studies have documented practice gaps in acne management between pediatricians and dermatologists. Evidence-based recommendations for acne management were published by the American Acne and Rosacea Society and the American Academy of Pediatrics in 2013. We assess the impact of a case-based learning intervention on pediatrician knowledge and treatment of acne in accordance with published recommendations.

METHODS

Participants were recruited at four conferences for pediatric providers. Knowledge of the recommendations and confidence in utilizing them was assessed. Five case-based questions were presented, with providers choosing acne treatments before, immediately after, and 3 months after a case-based educational presentation. Answer selections consistent with the recommendations were scored as correct, and all responses were evaluated for patterns of medication selection.

RESULTS

A total of 150 individuals participated, most with over 10 years experience. Knowledge of the recommendations and confidence in prescribing acne therapy was poor. The average preintervention management selections were 70% correct, increasing significantly to 86% 3 months after intervention (p < .01). The most significant improvements were demonstrated in provider's ability to choose regimens for moderate acne consistent with published recommendations, and in recommendation-consistent usage of retinoids and benzoyl peroxide (p < .05). Persisting practice gaps included a reluctance to use topical retinoids in preadolescents and lack of initiating oral combination therapies in patients with severe acne.

CONCLUSIONS

A case-based educational intervention significantly increased providers choosing acne treatments in accordance with evidence-based recommendations in an examination setting. Limitations of the study include an inability to assess actual provider prescribing behavior through this methodology.

The extinction of topical erythromycin therapy for acne vulgaris and concern for the future of topical clindamycin

OBJECTIVE

This study aims to evaluate changes in topical antibiotic prescribing trends for acne.

METHODS

We retrospectively reviewed the National Ambulatory Medical Care Survey data from 1993 to 2012 for all visits in which acne vulgaris was the primary diagnosis.

RESULTS

Acne vulgaris represented an estimated 94.5 million (92.3, 96.8) visits during the 20-year study period. Bivariate analysis showed that over time erythromycin use declined (p < 0.001) and clindamycin use rose (p = 0.10). Multivariate analysis showed that the likelihood of erythromycin use declined to near zero (p < 0.001), whereas clindamycin utilization increased (p < 0.05). PubMed searches of "erythromycin AND resistance" and "clindamycin AND resistance" demonstrated increasing publication frequency by year, fit with sigmoidal functions (erythromycin: R²=0.93 and clindamycin: R²=0.94). Yearly publications consistently exceeded 100 papers for erythromycin and clindamycin resistance in 1983 and 2003, respectively, roughly corresponding to the interval between reports of their utility in acne.

CONCLUSIONS

Our findings suggest topical erythromycin use for acne has essentially ceased. By contrast, clindamycin use is increasing. Current recommendations discourage topical antibiotic monotherapy in favor of combination therapy with benzoyl peroxide and topical retinoids. Our group's previous work demonstrated that this trend is indeed occurring.

Vacuum Sealing Drainage Treatment Combined with Antibiotic-Impregnated Bone Cement for Treatment of Soft Tissue Defects and Infection

Background

This study aimed to evaluate the combined effect of vacuum sealing drainage (VSD) and antibiotic-loaded bone cement on soft tissue defects and infection.

Material/Methods

This prospective non-blinded study recruited 46 patients with soft tissue defects and infection from January 2010 to May 2014 and randomly divided them into experimental and control groups (n=23). Patients in the experimental group were treated with VSD and antibiotic-loaded bone cement, while the patients in the control group were treated with VSD only.

Results

In the experimental group, the wound was healed in 23 cases at 4 weeks postoperatively, of which direct suture was performed in 12 cases, and additional free flap transplantation or skin grafting was performed in 6 cases and 5 cases, respectively. No infection reoccurred in 1-year follow-up. In the control group, the wound was healed in 15 cases at 6 weeks postoperatively, of which direct suture was performed in 8 cases, and additional free flap transplantation or skin grafting was performed in 3 cases and 4 cases, respectively. In the other 8 cases the wound was healed at 8 weeks postoperatively. Infection reoccurred in 3 cases during the follow-up. The experimental group had significantly fewer VSD dressing renewals, shorter time needed until the wound was ready for surgery, shorter duration of antibiotic administration, faster wound healing, and shorter hospital stay than the control group (p<0.01).

Conclusions

The combination of VSD and antibiotic bone cement might be a better method for treatment of soft tissue defects and infection.

The P450 system and mTORC1 signalling in acne

In this issue, Hellmann-Regen et al. suggested that anti-acne effects of erythromycin and tetracyclines may be related to their inhibitory effect of cytochrome P450-mediated degradation of all-trans-retinoic acid (ATRA). We have recently proposed that all anti-acne agents function by attenuation of increased mTORC1 signalling. This commentary links the P450 system to mTORC1 regulation in acne. Drug-mediated induction of P450 activity or P450 mutants with increased catabolic activity may reduce cellular ATRA levels and FoxO1 expression, thus reducing FoxO-mediated mTORC1 inhibition. In contrast, agents blocking ATRA degradation such as erythromycin and tetracyclines may improve acne by increasing FoxO1 expression with consecutive inhibition of mTORC1 signalling.

Emerging drugs for the treatment of acne

INTRODUCTION

Acne is the most common skin condition in the US. The mainstay of acne therapy includes: topical retinoids, topical antibiotics, benzoyl peroxide (BP), and oral isotretinoin for severe cases. Although these treatment options are highly effective they do have certain drawbacks. Current acne treatment regimens often require patients to use multiple medications, some of which may have irritating side effects. Furthermore, Propionibacterium acnes resistance to antibiotics has become an increasing problem due to the rise in antibiotic use.

AREAS COVERED

New therapies that have either been released onto the market or that are being developed include: adapalene-BP combination agent, dapsone 5% gel, minocycline foam, topical nitric oxide-releasing agent, cortexolone 17 α-propionate, and CIP isotretinoin. Some of these new therapies address the challenges faced with existing treatment options. For instance, the relatively new combination therapy, adapalene-BP, limits antibiotic resistance and also helps simplify treatment regimens. The newly developed topical nitric oxide-releasing agent also holds potential in limiting antibiotic resistance.

EXPERT OPINION

Many of the new therapies discussed in this paper are still in early stages of testing so it is difficult to predict their outlook; however, based on preliminary findings, these therapies seem to be promising.

Recent advances in acne pathogenesis: implications for therapy

Acne pathogenesis is a multifactorial process that occurs at the level of the pilosebaceous unit. While acne was previously perceived as an infectious disease, recent data have clarified it as an inflammatory process in which Propionibacterium acnes and innate immunity play critical roles in propagating abnormal hyperkeratinization and inflammation. Alterations in sebum composition, and increased sensitivity to androgens, also play roles in the inflammatory process. A stepwise approach to acne management utilizes topical agents for mild to moderate acne (topical retinoid as mainstay ± topical antibiotics) and escalation to oral agents for more resistant cases (oral antibiotics or hormonal agents in conjunction with a topical retinoid or oral isotretinoin alone for severe acne). Concerns over antibiotic resistance and the safety issues associated with isotretinoin have prompted further research into alternative medications and devices for the treatment of acne. Radiofrequency, laser, and light treatments have demonstrated modest improvement for inflammatory acne (with blue-light photodynamic therapy being the only US FDA-approved treatment). However, limitations in study design and patient follow-up render these modalities as adjuncts rather than standalone options. This review will update readers on the latest advancements in our understanding of acne pathogenesis and treatment, with emphasis on emerging treatment options that can help improve patient outcomes.