[Acne]. / Akne.

Acne vulgaris is one of the most frequent dermatological diseases with a lifetime prevalence of about 85%. The clinical spectrum shows a great variety. Key factors of pathogenesis are increased sebum production, hyperkeratinization of the follicular infundibulum, inflammatory processes, and a dysbiosis of the skin microbiome. In addition to endogenous factors (e.g., disturbances of the androgen metabolism) or other hormonal changes, exogenous factors (e.g., diet, mechanical irritation or the use of inappropriate cosmetics) can also play an important role. The clinical spectrum is broad, extending from neonatal Acne (A.) to adult A., from comedonal A. to fulminant A., from cosmetic A. to A. excoriée (skin picking disorder). The psychological effects of acne can be profound and can cause a severe reduction in quality of life. Therefore, in addition to an effective therapy with regular medical check-ups and good adherence, it is always necessary to consider psychological aspects.

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.

Biologic Therapy for Hidradenitis Suppurativa Plus Conglobate Acne Associated with SAPHO Syndrome: A Case Report.

is missing (Short Communication).

Expression of Potential Dermal Progenitor Cell Markers in the Tumour and Stroma of Skin Adnexal Malignant and Benign Tumours.

Stem cells are multipotent cells that maintain the skin epidermis including skin appendages such as hair follicle, sebaceous glands, and sweat glands. There is evidence that reciprocal signalling between the epidermis and the dermis plays an important role in skin development, homeostasis, wound repair, and skin cancer. The origin of skin cancer that derive from skin appendages is still controversial, including basal cell carcinoma and even more of rare tumours such as sebaceous carcinomas and whether those tumours originate from resident tissue stem cells. To investigate whether markers reported to label dermal progenitor cells are preserved in the tumour including the tumour stroma of skin adnexal tumours, we tested 45 human basal cell carcinomas, including superficial, nodular, adenoid, infiltrating, and sclerosing types, and further 38 human tumours of skin appendages including 13 sebaceous adenomas and carcinomas, 20 eccrine sweat gland tumours, and 5 pilomatricomas, syringomas, and hair follicle tumours for the expression of the potential dermal and epidermal cell markers CRABP1, Nestin, and Ephrin B2 and compared these findings with healthy, age-related human epidermis. We detected that CRABP1, Nestin, and Ephrin B2 are expressed in the intratumoural stroma as well as the tumour invasive front of skin tumours of appendages and BCCs.

Cytokine and Chemokine Recovery Is Increased by Colloid Perfusates during Dermal Microdialysis.

Cytokines and chemokines play important roles in cell signalling, and microdialysis is a promising tool for monitoring these inflammation markers ex vivo. Therefore, the collecting of these mediators at the highest concentrations possible is crucial. Depending on the size of the mediator of interest, the collection of these high molecular mass molecules has thus far been difficult due to their low recovery, even when using high cut-off (100 kDa) microdialysis membranes. This study aimed to optimize the recovery of various cytokines and chemokines by validating the use of different perfusates in cutaneous microdialysis, and comparing intravenous (i.v.) colloids, crystalloids, and a lipid emulsion formulations that are approved for i.v. METHODS: In vitro and in vivo recovery experiments using six recombinant cytokines varying in molecular size (interleukin-2 (15 kDa), interleukin-6 (20.5 kDa), interleukin-8 (8 kDa), interleukin-12p70 (70 kDa), TNF-α (17.5 kDa), and vascular endothelial growth factor (VEGF) (38 kDa)) were performed in the presence of different perfusates for i.v. APPLICATIONS: Ringer’s lactate, dextran 60 kDa, hydroxyethyl starch 70 kDa, and hydroxyethyl starch 200 kDa solutions as well as a lipid emulsion formulation. Recovery was determined through (i) microdialysis of cytokines and chemokines in Ringer’s lactate solution or human serum in vitro, and (ii) retrodialysis of excised porcine and human skin cadavers in vitro and porcine skin in vivo. Furthermore, we used skin trauma (catheter insertion) and Ultraviolet B irradiation of 3 × 3 cm² skin areas to sample cytokines and chemokines in vivo and compared the amounts that were obtained using crystalloid and colloid perfusates. All the cytokines and chemokines within the dialysates were quantified through a flow cytometry-based bead array assay. RESULTS: Overall, recovery was strongly increased by the colloids, particularly hydroxyethyl starch 70 kDa, in vitro, ex vivo, and in vivo. When compared with the recovery achieved using Ringer’s lactate, this increase was most effective for proteins ranging from 8 to 20.5 kDa. Hydroxyethyl starch 70 kDa significantly increased the recovery of interleukin (IL)-8 in human serum in vitro when compared with Ringer’s lactate. More cytokines and chemokines were recovered using colloids compared with crystalloids. However, the increase in recovery values was lower for IL-12p70 and VEGF. CONCLUSIONS: Regarding the dialysate volumes and final dialysate concentrations, colloid perfusates are overall superior to crystalloid perfusates, such as Ringer’s lactate, when sampling cytokines and chemokines, resulting in higher recoveries. However, the sampling of high-molecular-mass cytokines during microdialysis remains challenging, and experimental in vitro data are not completely comparable with data obtained ex vivo or in vivo.

Eczema in Psoriatico: An Important Differential Diagnosis Between Chronic Allergic Contact Dermatitis and Psoriasis in Palmoplantar Localization.

Differential diagnosis of palmoplantar non-pustular psoriasis and chronic allergic contact dermatitis (ACD) and the combination of these conditions, termed "eczema in psoriatico" (EIP), is difficult, especially in cases of isolated involvement. A blind re-evaluation of 63 archived formalin-fixed palmoplantar samples, previously diagnosed clinically as either psoriasis or chronic ACD, was performed. Samples were allocated to histopathological diagnoses of psoriasis, contact dermatitis or EIP. Immunohistological stainings were performed for better characterization. Immunochemistry of EIP revealed features that overlapped contemporarily with psoriasis (cytokeratin 17 (CK17), Ki67, interleukin (IL)-8, IL-17, IL-23) and with ACD (CD1a, major histocompatibility complex (MHC) class I, MHC class II, epidermal T-cell subsets). Surprisingly, a significantly much higher number of dermal CD8+ T cells was found in EIP than in ACD and psoriasis. In conclusion, this study provides insight into the immunohistological differentiation of palmoplantar psoriasis, chronic ACD and EIP.

Practical management of acne for clinicians: An international consensus from the Global Alliance to Improve Outcomes in Acne.

Scientific advances are continually improving the knowledge of acne and contributing to the refinement of treatment options; it is important for clinicians to regularly update their practice patterns to reflect current standards. The Global Alliance to Improve Outcomes in Acne is an international group of dermatologists with an interest in acne research and education that has been meeting regularly since 2001. As a group, we have continuously evaluated the literature on acne. This supplement focuses on providing relevant clinical guidance to health care practitioners managing patients with acne, with an emphasis on areas where the evidence base may be sparse or need interpretation for daily practice.

Anti-acne drugs in phase 1 and 2 clinical trials.

INTRODUCTION: Despite the impressive increase of knowledge on acne etiology accumulated during the last 20 years, few efforts have been overtaken to introduce new therapeutic regiments targeting the ideal treatment of acne. The increasing emergence of microbial resistance associated with antibiotics, teratogenicity, particularly associated with systemic isotretinoin, and the need for an adverse drug profile, which can be tolerated by the patient, make the need of new pathogenesis relevant anti-acne agents an emerging issue. Areas covered: A search for phase 1 and 2 acne treatment trials in the US National Institutes of Health database of clinical trials and the European Medicines Agency database with the key words 'acne' and 'treatment' was carried out, on 6 January 2017. Expert opinion: The detected trials mostly investigate topical agents that may act via sebosuppressive effects, antimicrobial properties or anti-inflammatory actions. The compounds under investigation include olumacostat glasaretil, cortexolone 17α-propionate, stearoyl-CoA desaturase 1 inhibitors, agents affecting the melanocortin system, omiganan, and minocycline. Systemic studied anti-acne drugs include finasteride, biologics, low dose anti-inflammatory antibiotics, and leukotriene B4 inhibitors.

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.

Kinetic Profile of Inflammation Markers in Human Skin In vivo Following Exposure to Ultraviolet B Indicates Synchronic Release of Cytokines and Prostanoids.

Ultraviolet B (UVB) irradiation affects epidermal cells, which respond via a cascade of inflammation markers. After initial in vitro and ex vivo experiments, this study used cutaneous microdialysis to generate a kinetic profile for 16 cytokines and 4 prostanoids in human skin in vivo. Skin areas 9 cm2 were irradiated with UVB (2× minimal erythematous dose) 16 h after catheter placement in the dermis of the volar forearms of healthy volunteers. Dialysates were collected at 4-h intervals up to 64 h and analysed for 5- and 8-iso-PGF2α, 9α,11α-PGF2α and PGE2 by gas chromatography-mass spectrometry (GC/MS). Dialysates were also analysed for interleukin (IL)-1ß, IL-2, IL-3, IL-4, IL-5, IL-6, IL-8, IL-10, tumour necrosis factor (TNF)-α, Fas ligand (FasL), interferon-γ-inducible protein-10 (IP-10), monocyte chemoattractant protein 1 (MCP-1), RANTES, eotaxin, and granulocyte-macrophage colony-stimulating factor (GM-CSF) using a multiplex-based cytometric-bead-array. In conclusion, 3 peaks with synchronic release of T helper (TH) 1-directed inflammatory cytokines and prostanoids could be detected post-UVB: an early phase (4-12 h), an intermediate phase (16-24 h) and a late phase (32-40 h). A TH2-directed cytokine response was detectable at intermediate and late phases.

Effects of Topical Tacrolimus and Polyunsaturated Fatty Acids on In Vivo Release of Eicosanoids in Atopic Dermatitis During Dermal Microdialysis.

Atopic dermatitis (AD) is a multifactorial inflammatory skin disease with release of distinct inflammatory signals. This study investigated the presence of eicosanoids in AD skin and the effect of topical agents with potential to suppress inflammation. Twelve patients with moderate AD received topical treatment on either arm with tacrolimus 0.1% ointment or a lotion containing 12% ω-6 fatty acids (polyunsaturated fatty acids; PUFA) twice daily for 5 consecutive days. Interstitial fluid was collected in vivo via dermal microdialysis from 4 defined skin areas: lesional, non-lesional and topically treated skin (tacrolimus or PUFA). Markers of oxidative stress (F2-isoprostanes; 5- and 8-prostaglandin F2α) and inflammation (9α,11α-prostaglandin F2α; and prostaglandin E2) were determined by gas chromatography-mass spectrometry. All eicosanoid levels were reduced in non-lesional and tacrolimus-treated skin. A significant reduction was observed in total F2-isoprostanes; 9α,11α-prostaglandin F2α; and prostaglandin E2 in non-lesional skin and in 9α,11α-prostaglandin F2α in tacrolimus-treated compared with untreated AD skin. In conclusion, treatment with tacrolimus compared with PUFA appears to suppress eicosanoids more efficiently in AD skin.

Efficacy of adapalene/benzoyl peroxide combination in moderate inflammatory acne and its impact on patient adherence.

BACKGROUND AND OBJECTIVES: Adapalene 0.1 %/benzoyl peroxide (BPO) 2.5 % (Epiduo®) is the first, fixed-dose topical combination gel developed for the once-daily treatment of acne. The objective of this observational study was to assess efficacy and patient adherence under daily clinical practice conditions in a large population of young adults and adolescents (12 to 20 years) with moderate inflammatory acne. PATIENTS AND METHODS: A total of 2 780 patients receiving adapalene-BPO were evaluated in this multicenter, open-label, prospective non-interventional observational study. Observation time per patient was approximately 12 weeks. Assessment parameters included changes in acne severity, treatment success, safety, and therapeutic adherence. RESULTS: After 12 weeks, the majority of patients (91.5 %) showed improvement of acne under adapalene-BPO treatment, with an initial therapeutic response noted after a median time of 14 days. Overall, 21.8 % of participants displayed complete resolution of visible acne lesions. Treatment adherence was assessed as good in 63.2 % of patients. The majority of individuals (69.5 %) experienced no or only mild local skin irritations. No serious adverse drug reactions (ADR) were reported during the course of the study. CONCLUSIONS: Adapalene-BPO is effective and safe in the treatment of moderate inflammatory acne. The fixed-dose combination and easy application simplifies the therapeutic regimen, leading to good treatment adherence in the majority of patients.

BLIMP1 is required for postnatal epidermal homeostasis but does not define a sebaceous gland progenitor under steady-state conditions.

B-lymphocyte-induced nuclear maturation protein 1 (BLIMP1) was previously reported to define a sebaceous gland (SG) progenitor population in the epidermis. However, the recent identification of multiple stem cell populations in the hair follicle junctional zone has led us to re-evaluate its function. We show, in agreement with previous studies, that BLIMP1 is expressed by postmitotic, terminally differentiated epidermal cells within the SG, interfollicular epidermis, and hair follicle. Epidermal overexpression of c-Myc results in loss of BLIMP1(+) cells, an effect modulated by androgen signaling. Epidermal-specific deletion of Blimp1 causes multiple differentiation defects in the epidermis in addition to SG enlargement. In culture, BLIMP1(+) sebocytes have no greater clonogenic potential than BLIMP1(-) sebocytes. Finally, lineage-tracing experiments reveal that, under steady-state conditions, BLIMP1-expressing cells do not divide. Thus, rather than defining a sebocyte progenitor population, BLIMP1 functions in terminally differentiated cells to maintain homeostasis in multiple epidermal compartments.

Not all acne is acne vulgaris.

BACKGROUND: Acne is the most common skin disease in adolescence, with a prevalence of nearly 100%. About 60% of affected adolescents have mild acne for which they use non-prescription preparations without consulting a physician. The remaining 40% constitute the population of acne patients seen in medical practice. The course of acne can be either acute or chronic; its manifestations can appear in waves, sometimes with dramatically severe inflammation leading rapidly to scarring. Acne often has adverse emotional consequences. Its treatment is markedly better than in the past because of new pharmacological and physicochemical approaches and because evidence-based guidelines are now available. METHOD: This article is based on a selective review of the literature and also incorporates the authors' own clinical and scientific experience. RESULTS: Acne vulgaris of grade I or II in an adolescent is generally not hard to treat. In contrast, the more severe grades III and IV and conglobate acne often present a therapeutic challenge, as they are associated with varying constellations of acute lesions, scarring, inflammation, and emotional disturbances. These conditions often require systemic treatment with tetracyclines, which are especially useful because of their para-antibiotic antiinflammatory effect. Severe cases must be treated with isotretinoin. Women can benefit from anti-androgenic contraceptive drugs. Retinoids or azelaic acid are used in maintenance therapy to suppress the formation of microcomedones, the precursor stage of acne lesions. CONCLUSION: A variety of effective treatments for acne are available, depending on the severity of the condition.

c-MYC-induced sebaceous gland differentiation is controlled by an androgen receptor/p53 axis.

Although the sebaceous gland (SG) plays an important role in skin function, the mechanisms regulating SG differentiation and carcinoma formation are poorly understood. We previously reported that c-MYC overexpression stimulates SG differentiation. We now demonstrate roles for the androgen receptor (AR) and p53. MYC-induced SG differentiation was reduced in mice lacking a functional AR. High levels of MYC triggered a p53-dependent DNA damage response, leading to accumulation of proliferative SG progenitors and inhibition of AR signaling. Conversely, testosterone treatment or p53 deletion activated AR signaling and restored MYC-induced differentiation. Poorly differentiated human sebaceous carcinomas exhibited high p53 and low AR expression. Thus, the consequences of overactivating MYC in the SG depend on whether AR or p53 is activated, as they form a regulatory axis controlling proliferation and differentiation.