Antibiotic Susceptibility of Cutibacterium acnes Strains Isolated from Israeli Acne Patients

Artificial intelligence-accelerated high-throughput screening of antibiotic combinations on a microfluidic combinatorial droplet system

Microfluidic platforms have been employed as an effective tool for drug screening and exhibit the advantages of lower reagent consumption, higher throughput and a higher degree of automation. Despite the great advancement, it remains challenging to screen complex antibiotic combinations in a simple, high-throughput and systematic manner. Meanwhile, the large amounts of datasets generated during the screening process generally outpace the abilities of the conventional manual or semi-automatic data analysis. To address these issues, we propose an artificial intelligence-accelerated high-throughput combinatorial drug evaluation system (AI-HTCDES), which not only allows high-throughput production of antibiotic combinations with varying concentrations, but can also automatically analyze the dynamic growth of bacteria under the action of different antibiotic combinations. Based on this system, several antibiotic combinations displaying an additive effect are discovered, and the dosage regimens of each component in the combinations are determined. This strategy not only provides useful guidance in the clinical use of antibiotic combination therapy and personalized medicine, but also offers a promising tool for the combinatorial screenings of other medicines.

Topical phage therapy in a mouse model of Cutibacterium acnes-induced acne-like lesions

Acne vulgaris is a common neutrophil-driven inflammatory skin disorder in which Cutibacterium acnes (C. acnes) is known to play a key role. For decades, antibiotics have been widely employed to treat acne vulgaris, inevitably resulting in increased bacterial antibiotic resistance. Phage therapy is a promising strategy to combat the growing challenge of antibiotic-resistant bacteria, utilizing viruses that specifically lyse bacteria. Herein, we explore the feasibility of phage therapy against C. acnes. Eight novel phages, isolated in our laboratory, and commonly used antibiotics eradicate 100% of clinically isolated C. acnes strains. Topical phage therapy in a C. acnes-induced acne-like lesions mouse model affords significantly superior clinical and histological scores. Moreover, the decrease in inflammatory response was reflected by the reduced expression of chemokine CXCL2, neutrophil infiltration, and other inflammatory cytokines when compared with the infected-untreated group. Overall, these findings indicate the potential of phage therapy for acne vulgaris as an additional tool to conventional antibiotics.

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.

Antibiotics and Antimicrobial Resistance in Acne: Epidemiological Trends and Clinical Practice Considerations

Antimicrobial resistance is an increasing public health problem worldwide. The interest of a focus on antimicrobial resistance in acne lies on the facts that acne vulgaris (acne) is the most common skin disease worldwide, that the bacterium Cutibacterium acnes (C. acnes, formerly Propionibacterium acnes) plays a key role in the pathogenesis of acne, while at the same time being part of the skin flora, and that antibiotics are commonly recommended for acne treatment. The overuse of topical and/or systemic antibiotics, the long treatment courses used for acne, and the availability of over-the-counter antibiotic preparations, have led to the worldwide emergence of resistant strains in acne patients. In this review, we discuss the epidemiological trends of antimicrobial resistance in acne, the need to avoid the perturbation of the skin microbiome caused by anti-acne antibiotics, and the clinical practice considerations related to the emergence of resistant strains in acne patients. In light of the increasing risk of antimicrobial resistance, raising concerns over the misuse of antibiotics, prescribing patterns can be a critical target for antibiotic stewardship efforts. Also, the selection of non-antibiotic therapies for acne, whenever possible, may offer significant advantages.

Antibiotic Resistance Risk with Oral Tetracycline Treatment of Acne Vulgaris

Almost 1 billion people worldwide have acne, and oral tetracyclines, including doxycycline and minocycline, are effective and frequently prescribed treatments for acne. However, there is growing concern for the development of antibiotic resistance with such widespread utilization by dermatologists. Additionally, tetracyclines are known to have various potential side effects, including gut dysbiosis, gastrointestinal upset, photosensitivity, dizziness, and vertigo. However, in 2018 a novel narrow-spectrum tetracycline, sarecycline, was Food and Drug Administration-approved to treat moderate-to-severe acne vulgaris in patients 9-years-old and above. Sarecycline was designed to target Cutibacterium acnes, the pathogenic bacterium in acne vulgaris, which may reduce the risk of resistance. This paper examines the growing concerns of antibiotic resistance due to oral tetracycline usage in the treatment of acne vulgaris, with a focus on the promising third-generation, narrow-spectrum tetracycline, sarecycline.

Phage Therapy in Israel, Past, Present, and Future

The fascinating scientific history of phage therapy has been documented in numerous publications. In this study, however, we focus on an angle of the story that hitherto has remained relatively neglected, namely, phage therapy treatments, and the protagonists that conducted these in Mandatory-Palestine and subsequently the state of Israel, as part of a global trend. We complete the story by describing efforts in the new era of phage therapy in present-day Israel.

Part I Antimicrobial resistance: Bacterial pathogens of dermatologic significance and implications of rising resistance

Although the COVID-19 pandemic has been the defining global health crisis of our time, public health officials have been sounding the alarm of another ominous threat for years: an impending antimicrobial resistance crisis. In dermatology, antibiotics are often used for prolonged courses in the treatment of skin and soft tissue infections and common inflammatory skin conditions, increasing the risk of microbiome alteration and antibiotic-related adverse effects, all while exerting consequential selective pressures on both pathogenic and bystander bacteria. In this review, we hope to raise awareness of the crisis of antimicrobial resistance and review resistance concerns related to dermatology-relevant bacterial pathogens.

Sarecycline Demonstrates Clinical Effectiveness against Staphylococcal Infections and Inflammatory Dermatoses: Evidence for Improving Antibiotic Stewardship in Dermatology

Tetracycline class antibiotics are widely used for multiple skin diseases, including acne vulgaris, acne rosacea, cutaneous infections, inflammatory dermatoses, and autoimmune blistering disorders. Concerns about antibiotic resistance and protecting the human/host microbiome beg the question whether broad-spectrum tetracyclines such as doxycycline and minocycline should be prescribed at such a high rate by dermatologists when a narrow-spectrum tetracycline derivative, sarecycline, exists. We evaluated the clinical effectiveness of oral sarecycline against cutaneous staphylococcal infections, eyelid stye, and mucous membrane pemphigoid to determine whether sarecycline is a viable option for clinicians to practice improved antibiotic stewardship. We observed significant improvement in staphylococcal infections and inflammatory dermatoses with courses of oral sarecycline as short as 9 days, with no reported adverse events. These clinical findings are consistent with in vitro microbiological data and anti-inflammatory properties of sarecycline. Our data provides a strong rationale for clinicians to use narrow-spectrum sarecycline rather than broad-spectrum tetracyclines as a first-line agent in treating staphylococcal skin infections and inflammatory skin diseases for which tetracyclines are currently commonly employed. Such advancement in the practice paradigm in dermatology will enhance antibiotic stewardship, reduce risk of antibiotic resistance, protect the human microbiome, and provide patients with precision medicine care.

A Janus-Faced Bacterium: Host-Beneficial and -Detrimental Roles of Cutibacterium acnes

The bacterial species Cutibacterium acnes (formerly known as Propionibacterium acnes) is tightly associated with humans. It is the dominant bacterium in sebaceous regions of the human skin, where it preferentially colonizes the pilosebaceous unit. Multiple strains of C. acnes that belong to phylogenetically distinct types can co-exist. In this review we summarize and discuss the current knowledge of C. acnes regarding bacterial properties and traits that allow host colonization and play major roles in host-bacterium interactions and also regarding the host responses that C. acnes can trigger. These responses can have beneficial or detrimental consequences for the host. In the first part of the review, we highlight and critically review disease associations of C. acnes, in particular acne vulgaris, implant-associated infections and native infections. Here, we also analyse the current evidence for a direct or indirect role of a C. acnes-related dysbiosis in disease development or progression, i.e., reduced C. acnes strain diversity and/or the predominance of a certain phylotype. In the second part of the review, we highlight historical and recent findings demonstrating beneficial aspects of colonization by C. acnes such as colonization resistance, immune system interactions, and oxidant protection, and discuss the molecular mechanisms behind these effects. This new insight led to efforts in skin microbiota manipulation, such as the use of C. acnes strains as probiotic options to treat skin disorders.

Antibacterial Mechanisms and Efficacy of Sarecycline in Animal Models of Infection and Inflammation

Prolonged broad-spectrum antibiotic use is more likely to induce bacterial resistance and dysbiosis of skin and gut microflora. First and second-generation tetracycline-class antibiotics have similar broad-spectrum antibacterial activity. Targeted tetracycline-class antibiotics are needed to limit antimicrobial resistance and improve patient outcomes. Sarecycline is a narrow-spectrum, third-generation tetracycline-class antibiotic Food and Drug Administration (FDA)-approved for treating moderate-to-severe acne. In vitro studies demonstrated activity against clinically relevant Gram-positive bacteria but reduced activity against Gram-negative bacteria. Recent studies have provided insight into how the structure of sarecycline, with a unique C7 moiety, interacts with bacterial ribosomes to block translation and prevent antibiotic resistance. Sarecycline reduces Staphylococcus aureus DNA and protein synthesis with limited effects on RNA, lipid, and bacterial wall synthesis. In agreement with in vitro data, sarecycline demonstrated narrower-spectrum in vivo activity in murine models of infection, exhibiting activity against S. aureus, but reduced efficacy against Escherichia coli compared to doxycycline and minocycline. In a murine neutropenic thigh wound infection model, sarecycline was as effective as doxycycline against S. aureus. The anti-inflammatory activity of sarecycline was comparable to doxycycline and minocycline in a rat paw edema model. Here, we review the antibacterial mechanisms of sarecycline and report results of in vivo studies of infection and inflammation.