MLST typing of antimicrobial-resistant Propionibacterium acnes isolates from patients with moderate to severe acne vulgaris

Microbiomes in Acne Vulgaris and Their Susceptibility to Antibiotics in Indonesia: A Systematic Review and Meta-Analysis

Hot and humid countries such as Indonesia have a higher prevalence of acne vulgaris (AV). The activity of skin microbes, not only Cutibacterium acnes, contribute to the formation of AV. Topical and oral antibiotics are routinely prescribed to treat AV. As antimicrobial resistance rates increase globally, there are concerns about decreased efficacy. This study intends to systematically evaluate the microbiomes isolated from AV lesions and their antibiotics susceptibility in Indonesia. The data were retrieved through PubMed, EMBASE, Google Scholar, and ScienceDirect searches for articles published until July 2022 using three multiword searches. Sixteen studies published between 2001 and 2022 were identified from which the data were pooled using a random effects model. The pooled prevalence estimates demonstrated that C. acnes, Staphylococcus epidermidis, and Staphylococcus aureus were the three common microbes associated with AV in Indonesia. Tetracyclines had lower resistance rates compared to those of macrolides and clindamycin, with C. acnes showing a resistance rate that is as high as 60.1% against macrolides. C. acnes resistance against minocycline showed an increasing trend, whereas the resistances to doxycycline, clindamycin, and macrolides stagnated. The high resistance prevalence and trends signify a public health concern. The results of this study call for the development of antibiotic stewardship programs in Indonesia, which may lead to improved acne outcomes.

Antibiotic Resistance in Acne: Mechanisms, Complications and Management

Antibiotic resistance in acne was first observed in the 1970s, and since the 1980s has become a major concern in dermatologic daily practice. The mechanisms for this type of resistance include biofilm formation that promotes virulence and the transmission of resistant bacterial strains. Genetic mutations with modification of ribosomal RNA, alteration in efflux pumps, and enzymatic inactivation are able to create resistance to tetracyclines and macrolides. The state of art in acne treatment is no longer to use antimicrobials as monotherapy. There should be a time limit for its use plus the employment of non-antibiotic maintenance. Earlier initiation of oral isotretinoin therapy should be considered in patients with insufficient response to antimicrobials, severe acne, or a history of repeated antimicrobial use. A better understanding of acne pathogenesis, the subtypes of Propionibacterium (also known as Cutibacterium) acnes, homeostasis of the skin microbiota, and the mechanisms of antibiotic resistance would be useful in the selection of narrow-spectrum or species-specific antimicrobials, as well as the non-antimicrobial, anti-inflammatory treatment of acne. A number of novel treatments awaiting clinical proof may include the use of bacteriophages, natural or synthetic antimicrobial peptides, probiotics, and biofilm-targeting agents, as well as the reassessment of phototherapy.

Efficacy and Safety of VB-1953 Topical Gel in Non-Responder Acne Patients with Clindamycin-Resistant Cutibacterium acnes

BACKGROUND AND OBJECTIVES

The emergence of resistant strains of Cutibacterium acnes can limit the efficacy of currently approved antibiotics for acne. VB-1953 is a next-generation antibiotic that exerts a bactericidal effect on resistant C. acnes. In this study, we investigated the safety, tolerability, and efficacy of VB-1953 topical gel in patients with moderate to severe acne having clindamycin-resistant C. acnes.

METHODS

An investigator-initiated, open label, single-arm clinical study was conducted in patients with moderate to severe facial acne vulgaris showing poor or no response to previous clindamycin treatment. Nineteen subjects were enrolled in the study based on laboratory screening for the presence of clindamycin-resistant C. acnes in acne swab samples collected from patients. VB-1953 2% gel was applied on the entire face twice daily over 12 weeks. The primary efficacy endpoints were absolute changes in inflammatory and noninflammatory lesion counts from baseline at week 12, while the secondary efficacy endpoint was the proportion of subjects achieving Investigator Global Assessment success (score of 0 or 1) or a grade 2 or higher improvement from baseline at week 12. The presence and severity of local skin reactions (erythema, edema, scaling/dryness, burning/stinging, pruritus) were evaluated for safety. Additionally, the detection and quantification of drug-resistant C. acnes strains were performed in the laboratory using acne swab samples collected from patients.

RESULTS

The occurrence of treatment-emergent adverse events or changes in vital signs, physical examinations, and urinalysis for any of the patients during the course of the entire study were clinically insignificant. Topical application of 2% VB-1953 topical gel resulted in a significant reduction of mean absolute inflammatory and noninflammatory lesion counts by 53.1% and 52.2%, respectively (p < 0.0001 for both), with an Investigator Global Assessment success of 26.3% at week 12 compared with baseline. Resistant bacteria were reduced by (94.3 ± 1%; p < 0.05) within 12 weeks of treatment with VB-1953.

CONCLUSION

These results indicate that VB-1953 topical gel can be a safe and effective therapy for moderate to severe acne with underlying resistant C. acnes in subjects who had not responded to previous antibiotic treatments.

Evaluating FMX-101 as a promising therapeutic for the treatment of acne

INTRODUCTION

Oral minocycline is a mainstay of therapy for moderate-to-severe acne; however, systemic side effects which include hepatotoxicity, lupus-like syndrome, drug hypersensitivity syndrome, autoimmune hepatitis, polyarteritis nodosa, gastrointestinal side effects and skin hyperpigmentation are of concern. Topical antibiotics commonly used in acne, such as erythromycin and clindamycin, present high P. acnes resistance rates which has opened the market for new topical antibiotics. FMX-101 is a novel topical minocycline foam that has shown promising results in phase I, II and III trials for the treatment of moderate-to-severe acne with a better safety profile than oral minocycline.

AREAS COVERED

The author provides an overview FMX-101 including its clinical efficacy and safety. The author then provides their expert opinion on this treatment and its potential for the treatment option for acne.

EXPERT OPINION

The topical foam formulation of FMX-101 has been shown to reduce both inflammatory and non-inflammatory lesions and to improve IGA scores in patients with moderate-to-severe acne without significant systemic absorption thus limiting associated side effects. Overall, the proven efficacy and safety profile of FMX-101, together with the low systemic absorption, high skin tolerability and cosmetically acceptable foam formulations render this novel therapy an important addition to the acne treatment armamentarium.

Cutibacterium acnes Isolates from Deep Tissue Specimens Retrieved during Revision Shoulder Arthroplasty: Similar Colony Morphology Does Not Indicate Clonality

Cutibacterium acnes is the most common bacterium associated with periprosthetic shoulder infections. Sequencing of C. acnes has been proposed as a potential rapid diagnostic tool and a method of determining subtypes associated with pathogenicity and antibiotic resistance patterns. When multiple deep samples from the same surgery are culture positive for the same species and the isolates show the same culture phenotype, it is typically assumed that these isolates are clonal. However, it is well-known that C. acnes is not clonal on the skin of most individuals. We hypothesized that the C. acnes bacteria recovered at the time of revision shoulder arthroplasty would often represent more than one subtype, and we tested this hypothesis in this work. For patients undergoing revision shoulder arthroplasty, multiple samples from the surgical field were taken. For those patients with multiple samples that were culture positive for C. acnes, isolates from each sample were subjected to full genome sequencing. Of 11 patients, 5 (45%) had different subtypes of C. acnes within the deep tissues even though the colony morphology was similar. One patient had four subtypes in the deep tissues, while four patients had two different subtypes. Up to four different subtypes of C. acnes were observed in the deep tissues of a single patient. Clonality of C. acnes isolates from deep specimens from a potential periprosthetic shoulder infection cannot be assumed. Sequence-based characterization of virulence and antibiotic resistance may require testing of multiple deep specimens.

Potential Role of the Microbiome in Acne: A Comprehensive Review

Acne is a highly prevalent inflammatory skin condition involving sebaceous sties. Although it clearly develops from an interplay of multiple factors, the exact cause of acne remains elusive. It is increasingly believed that the interaction between skin microbes and host immunity plays an important role in this disease, with perturbed microbial composition and activity found in acne patients. Cutibacterium acnes (C. acnes; formerly called Propionibacterium acnes) is commonly found in sebum-rich areas and its over-proliferation has long been thought to contribute to the disease. However, information provided by advanced metagenomic sequencing has indicated that the cutaneous microbiota in acne patients and acne-free individuals differ at the virulent-specific lineage level. Acne also has close connections with the gastrointestinal tract, and many argue that the gut microbiota could be involved in the pathogenic process of acne. The emotions of stress (e.g., depression and anxiety), for instance, have been hypothesized to aggravate acne by altering the gut microbiota and increasing intestinal permeability, potentially contributing to skin inflammation. Over the years, an expanding body of research has highlighted the presence of a gut–brain–skin axis that connects gut microbes, oral probiotics, and diet, currently an area of intense scrutiny, to acne severity. This review concentrates on the skin and gut microbes in acne, the role that the gut–brain–skin axis plays in the immunobiology of acne, and newly emerging microbiome-based therapies that can be applied to treat acne.

Acne, the Skin Microbiome, and Antibiotic Treatment

Acne vulgaris is a chronic skin disorder involving hair follicles and sebaceous glands. Multiple factors contribute to the disease, including skin microbes. The skin microbiome in the follicle is composed of a diverse group of microorganisms. Among them, Propionibacterium acnes and Malassezia spp. have been linked to acne development through their influence on sebum secretion, comedone formation, and inflammatory response. Antibiotics targeting P. acnes have been the mainstay in acne treatment for the past four decades. Among them, macrolides, clindamycin, and tetracyclines are the most widely prescribed. As antibiotic resistance becomes an increasing concern in clinical practice, understanding the skin microbiome associated with acne and the effects of antibiotic use on the skin commensals is highly relevant and critical to clinicians. In this review, we summarize recent studies of the composition and dynamics of the skin microbiome in acne and the effects of antibiotic treatment on skin microbes.

Propionibacterium acnes and Acne Vulgaris: New Insights from the Integration of Population Genetic, Multi-Omic, Biochemical and Host-Microbe Studies

The anaerobic bacterium Propionibacterium acnes is believed to play an important role in the pathophysiology of the common skin disease acne vulgaris. Over the last 10 years our understanding of the taxonomic and intraspecies diversity of this bacterium has increased tremendously, and with it the realisation that particular strains are associated with skin health while others appear related to disease. This extensive review will cover our current knowledge regarding the association of P. acnes phylogroups, clonal complexes and sequence types with acne vulgaris based on multilocus sequence typing of isolates, and direct ribotyping of the P. acnes strain population in skin microbiome samples based on 16S rDNA metagenomic data. We will also consider how multi-omic and biochemical studies have facilitated our understanding of P. acnes pathogenicity and interactions with the host, thus providing insights into why certain lineages appear to have a heightened capacity to contribute to acne vulgaris development, while others are positively associated with skin health. We conclude with a discussion of new therapeutic strategies that are currently under investigation for acne vulgaris, including vaccination, and consider the potential of these treatments to also perturb beneficial lineages of P. acnes on the skin.

Understanding the role of Propionibacterium acnes in acne vulgaris: The critical importance of skin sampling methodologies

Acne vulgaris is a chronic inflammatory skin condition classified by the Global Burden of Disease Study as the eighth most prevalent disease worldwide. The pathophysiology of the condition has been extensively studied, with an increase in sebum production, abnormal keratinization of the pilosebaceous follicle, and an inflammatory immune response all implicated in its etiology. One of the most disputed points, however, is the role of the gram-positive anaerobic bacterium Propionibacterium acnes in the development of acne, particularly when this organism is also found in normal sebaceous follicles of healthy skin. Against this background, we now describe the different sampling strategies that have been adopted for qualitative and quantitative study of P acnes within intact hair follicles of the skin and discuss the strengths and weaknesses of such methodologies for investigating the role of P acnes in the development of acne.

Canadian Clinical Practice Guidelines for Rosacea

Rosacea is a chronic facial inflammatory dermatosis characterized by background facial erythema and flushing and may be accompanied by inflammatory papules and pustules, cutaneous fibrosis and hyperplasia known as phyma, and ocular involvement. These features can have adverse impact on quality of life, and ocular involvement can lead to visual dysfunction. The past decade has witnessed increased research into pathogenic pathways involved in rosacea and the introduction of novel treatment innovations. The objective of these guidelines is to offer evidence-based recommendations to assist Canadian health care providers in the diagnosis and management of rosacea. These guidelines were developed by an expert panel of Canadian dermatologists taking into consideration the balance of desirable and undesirable outcomes, the quality of supporting evidence, the values and preferences of patients, and the costs of treatment. The 2015 Cochrane review "Interventions in Rosacea" was used as a source of clinical trial evidence on which to base the recommendations.