Acne vulgaris: a review of antibiotic therapy

Antibiotic resistance in dermatology: The scope of the problem and strategies to address it

Antibiotic resistance is a growing health concern that has attracted increasing attention from clinicians and scientists in recent years. Although resistance is an inevitable consequence of bacterial evolution and natural selection, misuse and overuse of antibiotics play a significant role in its acceleration. Antibiotics are the mainstay of therapy for common dermatoses, including acne and rosacea, as well as for skin and soft tissue infections. Therefore, it is critical for dermatologists and physicians across all disciplines to identify, appropriately manage, and prevent cases of antibiotic resistance. This review explores dermatologic conditions in which the development of antibiotic resistance is a risk and discusses mechanisms underlying the development of resistance. We discuss disease-specific strategies for overcoming resistant strains and improving antimicrobial stewardship along with recent advances in the development of novel approaches to counter antibiotic resistance.

A Polylysine dendrigraft is able to differentially impact Cutibacterium acnes strains preventing acneic skin

With a view to reducing the impact of Cutibacterium acnes on acne vulgaris, it now appears interesting to modify the balance between acneic and non-acneic strains of C. acnes using moderate approach. In the present study, we identified that a G2 dendrigraft of lysine dendrimer (G2 dendrimer) was able to modify membrane fluidity and biofilm formation of a C. acnes acneic strain (RT5), whereas it appeared no or less active on a C. acnes non-acneic strain (RT6). Moreover, skin ex vivo data indicated that the G2 is able to decrease inflammation (IL1α and TLR2) and improve skin desquamation after of C. acnes acneic strains colonization. Then, in vivo data confirmed, after C. acnes quantification by metagenomic analysis, that the G2 cream after 28 days of treatment was able to increase the diversity of C. acnes strains versus placebo cream. Data showed also a modification of the balance expression between C. acnes phylotype IA1 and phylotype II abundances. Taken together, the results confirm the interest of using soft compounds in cosmetic product for modifying phylotype abundances as well as diversity of C. acnes strains could be a new strategy for prevent acne vulgaris outbreak.

Guidance for the pharmacological management of acne vulgaris

INTRODUCTION

Many international guidelines and expert consensuses are available to help the clinician diagnose and treat acne vulgaris; however, a simplified practical guidance that integrates current existing published recommendations is still lacking. This article aims to give practical and simplified insight into the treatment of acne.

AREAS COVERED

Herein, the author discusses the treatment of comedonal, papulopustular, and nodular/cystic/conglobate acne. The author also proposes a simplified treatment escalation strategy that is based on disease severity and extension, starting with topical treatments for mild cases and progressing over to systemic therapies in more severe cases.

EXPERT OPINION

The ideal acne treatment would simultaneously and safely target all the pathogenic factors implicated in the appearance of acne lesions with minimal side effects. Since no such treatment currently exists, combination therapies are usually recommended for most types of acne. A major limitation in choosing an appropriate treatment plan is the discrepant use of classification systems across the published literature making it difficult to draw clear and succinct conclusions about the recommendations given. Acne is not a traditional infectious disease and so while antibiotics may improve symptoms, they do not reliably resolve the condition. Thus, there is currently a tendency to opt for antibiotic-sparing treatment strategies whenever possible.

A systematic review of N-acetylcysteine for treatment of acne vulgaris and acne-related associations and consequences: Focus on clinical studies

Acne vulgaris is one of the most common dermatologic disorders affects people of all races and ethnicities and has many adverse effects on the quality of life. The increased bacterial resistance to antibiotics has reduced the effectiveness of treatment with these agents. There is an increasing focus on the involvement of oxidative stress in the pathophysiology of acne. This study investigates the effect of N-acetylcysteine (NAC) as an antioxidant in the treatment of acne vulgaris. This systematic review was conducted through a search in databases such as Science Direct, PubMed, Scielo, and Medline using keywords including acne vulgaris, anti and NAC, and all the keywords associated with each of the subtitles. The factors affecting the occurrence and expansion of acne include increased sebum synthesis, hyperkeratinization of pilosebaceous units, colonization with Propionibacterium acnes, and increased release of inflammatory mediators and ROS. Studies have shown that glutathione stimulation following the administration of NAC increases glutathione levels for the detoxification of oxygen-free radicals. Moreover, NAC prevents the synthesis and release of inflammatory cytokines such as TNF-α, IL-8, IL-6, MP9, and IL-1β and has shown antibacterial activities against important bacteria including E. coli, S. epidermidis, Pseudomonas, and Klebsiella. This medication has anti-proliferative effects and is also used for excoriation and PCOD. The results of the present study showed the beneficial effects of using NAC in patients with acne vulgaris in terms of the disease complications and comorbidities. Given its diverse functional mechanisms, this medication can be used to treat acne and its consequences.

Oral Antibiotics for Acne

Oral antibiotics are integral for treating inflammatory acne based on what is understood about the pathogenesis as well as the role of Cutibacterium acnes. However, rising concerns of antibiotic resistance and the perception of "antibiotic phobia" create potential limitations on their integration in an acne treatment regimen. When prescribing oral antibiotics, dermatologists need to consider dosage, duration, and frequency, and to avoid their use as monotherapy. These considerations are important, along with the use of newer strategies and compounds, to reduce adverse-event profiles, antibiotic resistance, and to optimize outcomes. Aside from concomitant medications, allergies, and disease severity, costs and patient demographics can influence variability in prescribing plans. There are multiple published guidelines and consensus statements for the USA and Europe to promote safe antibiotic use by dermatologists. However, there is a lack of head-to-head studies and evidence for comparative superiority of any individual antibiotic, as well as any evidence to support the use of agents other than tetracyclines. Although oral antibiotics are one of the main options for moderate to severe acne, non-antibiotic therapy such as isotretinoin and hormonal therapies should be considered. As newer therapies and more outcomes data emerge, so will improved management of antibiotic therapy to foster patient safety.

Verantwortlicher Umgang mit Antibiotika: Notwendigkeit der Antibiotikareduktion in der Aknetherapie

Der übermäßige oder unkritische weltweite Einsatz von Antibiotika in der Medizin hat die Ausbreitung von Antibiotikaresistenzen beschleunigt. In einigen Bereichen sind viele Antibiotika bei bakteriellen Infektionen, die zuvor noch gut auf antibakterielle Wirkstoffe reagierten, mittlerweile wirkungslos geworden. Dermatologen/Venerologen setzten orale und topische Antibiotika bei der Behandlung von Acne vulgaris routinemäßig ein, obwohl Akne weder eine infektiöse Erkrankung ist noch alleine durch das Propionibacterium getriggert wird. Vielmehr ist sie eine komplexe, chronische entzündliche Hauterkrankung, die durch verschiedene pathogenetische Faktoren wie follikuläre Hyperkeratose, erhöhter Sebumproduktion, bakterielle Proliferation und Entzündung zustande kommt. Folglich sollte eine erfolgreiche Therapie auf die Bekämpfung verschiedener pathogenetischer Faktoren und nicht nur auf die von Propionibacterium acnes abzielen. Daher wurden topische Retinoide und Benzoylperoxid als Mittel der ersten Wahl definiert. Monotherapien mit lokalen Antibiotika sollten insgesamt vermieden werden. Systemische Antibiotika der Tetrazyklin-Gruppe haben bei bestimmen Krankheitsstadien ihren Sinn, ihre Wirkung könnte aber eher auf der antientzündlichen als auf der antibiotischen Reaktion beruhen. Gesundheitsbehörden ermahnen alle Gesundheitsdienstleister, den Einsatz von Antibiotika einzuschränken. Das Nutzen-Risiko-Verhältnis muss bei der Entscheidung für oder gegen eine antibiotische Therapie bei einem einzelnen Patienten immer auch in Bezug auf das öffentliche Interesse am Erhalt der Wirksamkeit von Antibiotika abgewogen werden. Im Folgenden werden das aktuelle Krankheitskonzept zu Acne vulgaris und die sich daraus ableitenden Konsequenzen für den Einsatz von Antibiotika vorgestellt.

Treatment of acne in children

Acne is a common skin condition in adolescents. It is not uncommon in childhood and it persists into adulthood. A broad range of acne treatments are available and have been shown to be safe and effective in adolescents and adults. However, there is limited literature regarding acne treatment in childhood and its available therapeutic options. It seems reasonable to extrapolate findings of the various studies reported on treatment of acne in the adolescent and adult age group, with the exclusion of the use of tetracycline derivatives. As clinicians, we must be more familiar with the clinical presentation of acne and available treatment options in our younger patients. Early recognition of acne with prompt and appropriate initiation of therapy in childhood will help prevent severe scarring in children.

Staphylococcus aureus in Acne Pathogenesis: A Case-Control Study

BACKGROUND

There is considerable evidence which suggests a possible pathogenetic role for Staphylococcus aureus (S. aureus) in acne vulgaris.

AIM

The study was to determine S. aureus colonization and antibiotic susceptibility patterns in patients with acne and of healthy people.

MATERIALS AND METHODS

In the case-control study, a total of 324 people were screened for nasal carriage of S. aureus: 166 acne patients and 158 healthy persons. One control subject was individually matched to one case. Nasal swabs from anterior nares of individuals were cultured and identified as S. aureus. Antibiotic sensitivity was performed with recognized laboratory techniques.

RESULTS

S. aureus was detected in 21.7% of the subjects in acne, and in 26.6% of control groups. There was no statistical difference in colonization rates between two groups (P=0.3). In patient group, most of S. aureus isolates were resistant to doxicycline and tetracycline (P=0.001), and were more sensitive to rifampicin compared to other drugs. In control samples, the isolated demonstrated higher resistance to cotrimoxazole compared to patient samples (P=0.0001). There was no difference between groups regarding resistance to rifampicin, vancomycin, methicillin, and oxacillin.

CONCLUSION

It is still unclear whether S. aureus is actually a causal agent in the pathogenesis of acne. Based on microbiological data of both healthy and acne-affected persons, we propose that contribution of S. aureus in acne pathogenesis is controversial.

Blue light for infectious diseases: Propionibacterium acnes, Helicobacter pylori, and beyond?

Blue light, particularly in the wavelength range of 405-470 nm, has attracted increasing attention due to its intrinsic antimicrobial effect without the addition of exogenous photosensitizers. In addition, it is commonly accepted that blue light is much less detrimental to mammalian cells than ultraviolet irradiation, which is another light-based antimicrobial approach being investigated. In this review, we discussed the blue light sensing systems in microbial cells, antimicrobial efficacy of blue light, the mechanism of antimicrobial effect of blue light, the effects of blue light on mammalian cells, and the effects of blue light on wound healing. It has been reported that blue light can regulate multi-cellular behavior involving cell-to-cell communication via blue light receptors in bacteria, and inhibit biofilm formation and subsequently potentiate light inactivation. At higher radiant exposures, blue light exhibits a broad-spectrum antimicrobial effect against both Gram-positive and Gram-negative bacteria. Blue light therapy is a clinically accepted approach for Propionibacterium acnes infections. Clinical trials have also been conducted to investigate the use of blue light for Helicobacter pylori stomach infections and have shown promising results. Studies on blue light inactivation of important wound pathogenic bacteria, including Staphylococcus aureus and Pseudomonas aeruginosa have also been reported. The mechanism of blue light inactivation of P. acnes, H. pylori, and some oral bacteria is proved to be the photo-excitation of intracellular porphyrins and the subsequent production of cytotoxic reactive oxygen species. Although it may be the case that the mechanism of blue light inactivation of wound pathogens (e.g., S. aureus, P. aeruginosa) is the same as that of P. acnes, this hypothesis has not been rigorously tested. Limited and discordant results have been reported regarding the effects of blue light on mammalian cells and wound healing. Under certain wavelengths and radiant exposures, blue light may cause cell dysfunction by the photo-excitation of blue light sensitizing chromophores, including flavins and cytochromes, within mitochondria or/and peroxisomes. Further studies should be performed to optimize the optical parameters (e.g., wavelength, radiant exposure) to ensure effective and safe blue light therapies for infectious disease. In addition, studies are also needed to verify the lack of development of microbial resistance to blue light.

Topical antimicrobial treatment of acne vulgaris: an evidence-based review

Topical antimicrobial treatment is indicated for mild to moderate acne vulgaris. Our literature review includes searches of Ovid, MEDLINE, EMBASE, and the databases of the Cochrane Library. A detailed search strategy is included. All searches were limited to controlled trials and systematic reviews. No year limits were applied to the searches, but we focused on trials, guidelines, and reviews published since 2004, the year that the last review of topical antimicrobials was published in this journal. Several controlled trials demonstrate that benzoyl peroxide, topical antibiotics, and topical retinoids used in combination provide the greatest efficacy and safety profile for the treatment of mild to moderate acne, but there are few trials directly comparing different combinations of these topical therapies with one another. Additionally, robust studies comparing cost and efficacy of generic combinations of the above agents with proprietary fixed-dose combination therapies that may increase compliance are also lacking. Although they have not been extensively studied, alternative agents including dapsone, salicylic acid, azelaic acid, and zinc are safe and efficacious when combined with traditional therapies.

Antibiotic susceptibility in prostate-derived Propionibacterium acnes isolates

The aim of this study was to determine antibiotic susceptibility of Propionibacterium acnes isolates from prostate. Prostate-derived P. acnes isolates (n = 24, Umeå & Örebro, Sweden, 2007-2010) and a panel of control strains (n = 25, Sweden) collected from skin and deep infections were assessed for resistance to penicillin G, piperacillin-tazobactam, imipenem, gentamicin, azithromycin, erythromycin, vancomycin, ciprofloxacin, moxifloxacin, tetracycline, tigecycline, fusidic acid, clindamycin, rifampicin, linezolid, daptomycin, trimethoprim-sulfamethoxazole, and metronidazole. In addition, the isolates were tested for inducible clindamycin resistance. All prostate derived P. acnes isolates displayed wild-type distribution of MIC-values, without evidence of acquired resistance. In the reference panel, 5 of 25 isolates had acquired macrolide resistance with cross-resistance to azithromycin, clindamycin, and erythromycin. In addition, one of these isolates was resistant to tetracycline.

Acne vulgaris: pathogenesis, treatment, and needs assessment

Acne vulgaris is a common skin condition with substantial cutaneous and psychologic disease burden. Studies suggest that the emotional impact of acne is comparable to that experienced by patients with systemic diseases, like diabetes and epilepsy. In conjunction with the considerable personal burden experienced by patients with acne, acne vulgaris also accounts for substantial societal and health care burden. The pathogenesis and existing treatment strategies for acne are complex. This article discusses the epidemiology, pathogenesis, and treatment of acne vulgaris. The burden of disease in the United States and future directions in the management of acne are also addressed.

Treating acne with antibiotic-resistant bacterial colonization

INTRODUCTION

Acne is a chronic skin disorder of the pilosebaceous unit; it has a multifactorial pathogenesis. Propionibacterium acnes within the follicle is considered to be a triggering factor of inflammation in acne. Antibiotics have been the primary treatment against P. acnes for more than 40 years. However, a gradual increase in the prevalence of antibiotic-resistant strains of P. acnes has been observed.

AREAS COVERED

This review discusses the pathophysiology of antibiotic-resistant acne development. It focuses on strategies to minimize the development of resistance and, most importantly, confront the development of antibiotic-resistant acne. The literature search was conducted up to August 2010, using the search terms 'acne', 'antibiotic-resistant acne' and 'bacterial resistance'.

EXPERT OPINION

Antibiotic-resistant acne is a real phenomenon. Strategies to prevent and confront it should include not only the use of certain treatment regimens but also rational prescribing policies, combination therapies, use of antibacterial non-antibiotic agents and treatment options targeting all the pathogenetic components of acne. Benzoyl-peroxide-based treatment is the most evidence-based approach. Oral isotretinoin remains the most efficacious option for severe acne.

Activities of ten essential oils towards Propionibacterium acnes and PC-3, A-549 and MCF-7 cancer cells

Ten essential oils, namely, mint (Mentha spicata L., Lamiaceae), ginger (Zingiber officinale Rosc., Zingiberaceae), lemon (Citrus limon Burm.f., Rutaceae), grapefruit (Citrus paradisi Macf., Rutaceae), jasmine (Jasminum grandiflora L., Oleaceae), lavender (Mill., Lamiaceae), chamomile (Matricaria chamomilla L., Compositae), thyme (Thymus vulgaris L., Lamiaceae), rose (Rosa damascena Mill., Rosaceae) and cinnamon (Cinnamomum zeylanicum N. Lauraceae) were tested for their antibacterial activities towards Propionibacterium acnes and in vitro toxicology against three human cancer cell lines. Thyme, cinnamon and rose essential oils exhibited the best antibacterial activities towards P. acnes, with inhibition diameters of 40 ± 1.2 mm, 33.5 ± 1.5 mm and 16.5 ± 0.7 mm, and minimal inhibitory concentrations of 0.016% (v/v), 0.016% (v/v) and 0.031% (v/v), respectively. Time-kill dynamic procedures showed that thyme, cinnamon, rose, and lavender essential oils exhibited the strongest bactericidal activities at a concentration of 0.25% (v/v), and P. acnes was completely killed after 5 min. The thyme essential oil exhibited the strongest cytotoxicity towards three human cancer cells. Its inhibition concentration 50% (IC₅₀) values on PC-3, A549 and MCF-7 tumor cell lines were 0.010% (v/v), 0.011% (v/v) and 0.030% (v/v), respectively. The cytotoxicity of 10 essential oils on human prostate carcinoma cell (PC-3) was significantly stronger than on human lung carcinoma (A549) and human breast cancer (MCF-7) cell lines.

Inhibitory effects of Fortunella japonica var. margarita and Citrus sunki essential oils on nitric oxide production and skin pathogens

A number of essential oils from citrus peels are claimed to have biological activities. Citrus peel, called 'Jin-Pi', is used in traditional medicine for digestion, severe cold, and fever. However, the antibacterial activities against skin pathogens and anti-inflammatory effects of the essential oils of Citrus sunki (JinGyul) and Fortunella japonica var. margarita (GumGyul) have not yet been described. Therefore, in this study, the essential oils of the citrus species C. sunki (CSE) and F. japonica var. margarita (FJE), both native to the island of Jeju, Korea, were examined for their anti-inflammatory and antimicrobial activities against skin pathogens. Four human skin pathogenic microorganisms, Staphylococcus epidermidis CCARM 3709, Propionibacterium acnes CCARM 0081, Malassezia furfur KCCM 12679, and Candida albicans KCCM 11282, were studied. CSE and FJE exhibited strong antimicrobial activity against most of the pathogenic bacteria and yeast strains that were tested. Interestingly, CSE and FJE even showed antimicrobial activity against antibiotic-resistant S. epidermidis CCARM 3710, S. epidermidis CCARM 3711, P. acnes CCARM9009, and P. acnes CCARM9010 strains. In addition, CSE and FJE reduced the lipopolysaccharide (LPS)-induced secretion of nitric oxide (NO) in RAW 264.7 cells, indicating that they have anti-inflammatory effects. We also analysed the chemical composition of the oils by gas chromatography-mass spectrometry (GC-MS) and identified several major components, including dl-limonene (68.18%) and beta-myrcene (4.36%) for CSE, and dl-limonene (61.58%) and carvone (6.36%) for FJE. Taken together, these findings indicate that CSE and FJE have great potential to be used in human skin health applications.

Assessing potential human health hazards and benefits from subtherapeutic antibiotics in the United States: tetracyclines as a case study

Many scientists, activists, regulators, and politicians have expressed urgent concern that using antibiotics in food animals selects for resistant strains of bacteria that harm human health and bring nearer a "postantibiotic era" of multidrug resistant "super-bugs." Proposed political solutions, such as the Preservation of Antibiotics for Medical Treatment Act (PAMTA), would ban entire classes of subtherapeutic antibiotics (STAs) now used for disease prevention and growth promotion in food animals. The proposed bans are not driven by formal quantitative risk assessment (QRA), but by a perceived need for immediate action to prevent potential catastrophe. Similar fears led to STA phase-outs in Europe a decade ago. However, QRA and empirical data indicate that continued use of STAs in the United States has not harmed human health, and bans in Europe have not helped human health. The fears motivating PAMTA contrast with QRA estimates of vanishingly small risks. As a case study, examining specific tetracycline uses and resistance patterns suggests that there is no significant human health hazard from continued use of tetracycline in food animals. Simple hypothetical calculations suggest an unobservably small risk (between 0 and 1.75E-11 excess lifetime risk of a tetracycline-resistant infection), based on the long history of tetracycline use in the United States without resistance-related treatment failures. QRAs for other STA uses in food animals also find that human health risks are vanishingly small. Whether such QRA calculations will guide risk management policy for animal antibiotics in the United States remains to be seen.

Emerging drugs for acne

Acne vulgaris is a common skin disorder that affects most individuals at some point in their lives. It may result in significant morbidity, including cutaneous scarring and psychological impairment. Current treatments include topical retinoids, benzoyl peroxide, topical and systemic antibiotics, and systemic isotretinoin. There are growing concerns of rising antibiotic resistance, significant side effects of isotretinoin therapy, and lack of safe and effective treatment for pregnant females. Recent advances in the pathogenesis of acne have led to a greater understanding of the underlying inflammatory mechanisms and the role the Propionibacterium acnes and biofilms. This has led to the development of new therapeutic targets. This article reviews emerging treatments of acne, including topical picolinic acid, topical antibiotic dapsone, systemic zinc salts, oral antibiotic lymecycline, new formulations of and synergistic combinations of benzoyl peroxide, photodynamic therapy with topical photosensitizers and potential acne vaccines.

Optimizing use of oral antibiotics in acne vulgaris

Oral antibiotics are commonly used to treat acne vulgaris, primarily in patients presenting with moderate to severe facial or truncal disease severity. These agents are most appropriately used in combination with a topical regimen containing benzoyl peroxide and a topical retinoid. The most common oral antibiotics for treating acne vulgaris are the tetracycline derivatives, although macrolide agents such as erythromycin have also been used extensively. Over the past 4 decades, as the sensitivity of Propionibacterium acnes to several oral and topical antibiotics has decreased, the efficacy of oral tetracycline and erythromycin has markedly diminished, leading to increased use of doxycycline, minocycline, and other agents, such as trimethoprim/sulfamethoxazole.

Acne through the ages: case-based observations through childhood and adolescence

Acne vulgaris is a common disorder that affects more than 17 million individuals in the United States. Knowledge of the disease is an important part of clinical practice, particularly for the pediatric practitioner. Contrary to common belief, acne is not a disease limited to adolescents and young adults but can occur at any stage of life. This article is a case-based review of acne during childhood and adolescence. Workup is based on age and concurrent physical findings, whereas therapy depends on the type of skin lesions along with patient characteristics and preferences.

Systemische Aknetherapie

The development of scarring in inflammatory acne may induce permanent disfigurement and considerable psychosocial impact on the lives of affected individuals. The early use of systemic acne therapy can help to prevent these unfortunate consequences. Antiinflammatory antibiotics such as tetracyclines are required in moderate to severe papulopustular acne. The recommended treatment duration is 3 months; combination with topical retinoids and benzoyl peroxide increases the speed and efficacy of lesion reduction and helps to prevent bacterial resistance. Oral isotretinoin is the treatment of choice in severe acne resistant to adequate conventional therapy. Hormonal treatment represents an alternative regimen for women with acne and is the first choice in late-onset acne and in those with clinical signs of hyperandrogenism.