[Current dermatology guidelines in Germany and Europe : A selection of clinically relevant recommendations]

Clinical practice guidelines are systematically developed decision aids for specific medical conditions. In Germany, national dermatology guidelines are developed chiefly under the aegis of the German Dermatological Society in collaboration with the Professional Association of German Dermatologists. European and international dermatological guidelines also exist and are developed by a range of organisations, such as the European Centre for Guidelines Development, which was founded by the European Dermatology Forum in 2018. In the years 2019 and 2020, new or updated German national guidelines were published on topics such as pathological scars (hypertrophic scars and keloids), cutaneous lupus erythematosus, pyoderma grangrenosum, anal pruritus, anal eczema, anal canal and anal rim carcinomas, as well as the prevention of HPV-associated neoplasms through vaccination, syphilis and the systemic treatment of neurodermitis. A new European guideline on lichen planus closes a gap in the spectrum of guidelines available in Germany. Key recommendations and relevant changes in the guidelines are presented in this article.

Artificial Intelligence in Plastic Surgery: Applications and Challenges

New developments in artificial intelligence (AI) offer opportunities to enhance plastic surgery practice, research, and education. In this article, we review relevant AI tools and applications, including machine learning, reinforcement learning, and natural language processing. Our own Markov decision process for keloid treatment illustrates how these models are developed and can be used to enhance decision-making in clinical practice. Finally, we discuss challenges of implementing AI and knowledge gaps that must be addressed to successfully apply AI in plastic surgery. Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Invited Discussion On: Efficacy and Safety of Intralesional Triamcinolone Versus Combination of Triamcinolone with 5-Fluorouracil in the Treatment of Keloids and Hypertrophic Scars: A Systematic Review and Meta-Analysis

Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The histotopographic features of formation of keloid scars of maxillofacial localization

OBJECTIVE

The aim: Study of the influence of local oxygen deficiency on the features of the formation of keloid scars of the head and neck.

PATIENTS AND METHODS

Materials and methods: The research material was 17 incisional biopsy specimens of keloid scars, which were the highest age categories of patients from 19 to 63 years.

RESULTS

Results: It was revealed that at coloring according to Mallory's technique, sections of fibrinoid swelling of collagen fibers were noted near central homogeneous hyaline masses. The lateral areas of the dermis that adjacent to keloid scar tissue, at coloring by the Hart method, in our modification, were characterized by the separation of the hyalinosis zone from the undamaged dermis by coarse bundles of elastic fibers that are colored in dark purple. The undifferentiated dysplasia of the connective tissue has caused the replacement and obstruction of single vascular components, which has complicated the local oxygen deficiency of keloid-altered tissues.

CONCLUSION

Conclusions: Thus, plasmaragia and the accumulation of protein deposits in the perivascular space determine the inhibition of local hemodynamics, which explains the decrease in oxygen transport to tissues. Decreased oxygenation and increased permeability of the vascular wall causes local hemocirculatory hypoxia.

[Keloid of the external auditory canal]

Own clinical observation of the keloid of the external auditory canal is reported. This is a very rare variant of the localization of this tumor. A description of this neoplasm is rare in domestic and foreign literature.

Site-specific keloid fibroblasts alter the behaviour of normal skin and normal scar fibroblasts through paracrine signalling

Keloid disease (KD) is an abnormal cutaneous fibroproliferative disorder of unknown aetiopathogenesis. Keloid fibroblasts (KF) are implicated as mediators of elevated extracellular matrix deposition. Aberrant secretory behaviour by KF relative to normal skin fibroblasts (NF) may influence the disease state. To date, no previous reports exist on the ability of site-specific KF to induce fibrotic-like phenotypic changes in NF or normal scar fibroblasts (NS) by paracrine mechanisms. Therefore, the aim of this study was to investigate the influence of conditioned media from site-specific KF on the cellular and molecular behaviour of both NF and NS enabled by paracrine mechanisms. Conditioned media was collected from cultured primary fibroblasts during a proliferative log phase of growth including: NF, NS, peri-lesional keloid fibroblasts (PKF) and intra-lesional keloid fibroblasts (IKF). Conditioned media was used to grow NF, NS, PKF and IKF cells over 240 hrs. Cellular behavior was monitored through real time cell analysis (RTCA), proliferation rates and migration in a scratch wound assay. Fibrosis-associated marker expression was determined at both protein and gene level. PKF conditioned media treatment of both NF and NS elicited enhanced cell proliferation, spreading and viability as measured in real time over 240 hrs versus control conditioned media. Following PKF and IKF media treatments up to 240 hrs, both NF and NS showed significantly elevated proliferation rates (p<0.03) and migration in a scratch wound assay (p<0.04). Concomitant up-regulation of collagen I, fibronectin, α-SMA, PAI-1, TGF-β and CTGF (p<0.03) protein expression were also observed. Corresponding qRT-PCR analysis supported these findings (P<0.03). In all cases, conditioned media from growing marginal PKF elicited the strongest effects. In conclusion, primary NF and NS cells treated with PKF or IKF conditioned media exhibit enhanced expression of fibrosis-associated molecular markers and increased cellular activity as a result of keloid fibroblast-derived paracrine factors.

[Inhibitory effect of Typhonium gigantewm Engl. on in vitro cultured human keloid fibroblasts]

OBJECTIVE

To study the inhibitory effect of Typhonium gigantewm Engl. (AEoTGE) on the proliferation and apoptosis of KFB in vitro and to survey the death rate.

METHODS

Samples of hypertrophic scars were collected and cultured. Only 4-8 passage cells were selected for experiment. Inverted microscope and transmission electron microscope were used to observe the morphogenesis and ultrastructure of KFB. The KFB cells were treated with AEoTGE in different concentrations(3. 125,6.250, 12.500, 25.000, 50. 000,100.000 g/L) for 24 hours. The effect of AEoTGE on the proliferation and the IC50 of KFB was observed with MTT assay and EdU. The effect of AEoTGE on apoptosis of KFB was detected by flow cytometry.

RESULTS

It showed that AEoTGE could inhibit the proliferation of KFB in an concentration-dependent style within the range of 3. 125-100.000 g/L. The AEoTGE could obviously increase the apoptosis rate of the KFB compared with blank control group(P <0.05). The IC50 of AEoTGE was 35 g/L. FITC-Annexin V/PI showed that apoptosis rate of KFB in the AEoTGE group was (72. 07 +/- 0. 70)% , while it was 23. 5% in blank control group (P < 0. 05).

CONCLUSIONS

AEoTGE could significantly inhibit the proliferating activity and induce apoptosis of KFB after co-culture for 24 hours. The IC50 is 35 g/L and the rate of apoptosis is (72.07 +/- 0.70)%.

Complications of bone-anchored hearing devices

Complications of bone-anchored hearing devices occur with both soft tissue and bone. Soft tissue complications are much more common and most often involve irritation of the skin surrounding the implant. Other complications include: skin flap necrosis, wound dehiscence, bleeding or hematoma formation, and persistent pain. Bone complications are classified as either early or late. Early complications are due to failure of osseointegration, while late complications are usually the result of either chronic infection or trauma. Pediatric patients are a unique group of implant patients and are more likely to have complications of both soft tissue and bone. Most complications can be managed in the office with topical therapy and wound care, although revision surgery may be required in extensive skin overgrowth cases. Proper patient selection, meticulous surgical technique, and patient hygiene around the implant are the most critical aspects in minimizing complications in patients with osseointegrated implants.

Buttonhole cannulation technique in a patient with keloid scarred skin on home hemodialysis: a case study

The buttonhole cannulation technique is the recommended and preferred approach for patients with an arteriovenous fistula on home hemodialysis; however, keloid formation from previous access techniques may preclude buttonhole cannulation. This case study details how buttonhole cannulation can be successful despite keloid formation in a patient on home hemodialysis.

A wound contraction experimental model for studying keloids and wound-healing modulators

Preventing and treating hypertrophic and keloid scars is difficult because of the lack of knowledge about their genesis. Tissue repair can be studied with biocompatible matrices and ex vivo cultures of different cell types. We used an experimental model where collagen gels populated by human fibroblasts underwent progressive contraction, allowing the study of wound healing remodeling. The fibroblast-populated lattices showed the greater contraction of the gel populated by fibroblasts from keloids versus fibroblasts from normal skin. Moreover, fibroblast growth factor (FGF) and transforming growth factor beta (TGF-beta) involved in scar formation were added to the collagen gels populated by normal skin fibroblasts. TGF-beta caused an increase in gel contraction; FGF did not. The mean percentages of contraction of the gels populated by keloid fibroblasts were very similar to the percentages of gels populated by normal skin fibroblasts with added TGF-beta. These observations confirm the existing hypothesis that TGF-beta may be involved in keloid formation.

Clinical quiz. Rubinstein-Taybi syndrome (synonyms: broad thumbs and great toes, characteristic facies, and mental retardation -- broad thumb-hallux syndrome)

A 28-year-old mentally retarded, institutionalised woman was referred to us for evaluation of multiple plantar warts and ingrown nails of both great toes. The patient was born to unrelated parents of North African origin and had one brother and three half-brothers, all of whom were healthy. Physical examination revealed short stature, slight obesity, facial abnormalities (Fig. 1), short and broad thumbs and big toes (Figs. 2 and 3). A keloid was found on the right forearm, that had developed after surgical correction of a fracture (Fig. 4). Ill-defined hyperpigmented macules were observed on the trunk. The patient also presented pruritic eczematous lesions of the limbs and the back that had been present for some years and were recurrent despite treatment with emollients and local steroids. Androgenetic-type alopecia of moderate severity was seen on the vertex of the scalp. Past medical history included polydactylism of the feet and clinodactyly of the thumbs (both corrected surgically), respiratory tract infections, Wolf-Parkinson-White syndrome and refractive errors necessitating glasses.

POMC and fibroblast biology

We evidenced in vitro proopiomelanocortin (POMC) mRNA-transcription in human dermal fibroblasts using Northern blot hybridization. Modulation of POMC gene expression by cytokines (transforming growth factor-beta, TGF-beta, and tumor necrosis factor-alpha, TNF-alpha) was investigated by incubating human normal fibroblasts with 1 and 10 ng/ml cytokines, either alone or in combination, for 24 hours. Our results show that dermal fibroblasts express POMC at significant levels under unstimulated conditions. POMC steady-state levels were significantly reduced by addition of TGF-beta. On the other hand, TNF-alpha exerted a stimulatory effect on POMC mRNA transcription, partially counteracting the effect of TGF-beta. These data provide the first demonstration of POMC gene expression in cultured skin fibroblasts. The opposite regulatory effect of TGF-beta and TNF-alpha, two cytokines primarily involved in extracellular matrix regulation, suggests a possible role for POMC-derived peptides in fibroblast activity. We also investigated POMC mRNA expression in keloid-derived fibroblasts in culture, and its regulation by TGF-beta added at the highest concentration documented for inhibition. Keloid-derived fibroblasts showed clearly detectable levels of POMC mRNA in basal conditions, and no alteration of POMC gene expression was observed when TGF-beta was added in culture. The altered TGF-beta regulation of POMC mRNA levels suggest that POMC-derived peptides may play a role in the pathogenesis of keloid formation through an autocrine/paracrine network, resulting in modulation of extracellular matrix synthesis.

Tamoxifen downregulates TGF-beta production in keloid fibroblasts

Keloids occur only in humans and are characterized by fibroblast overproduction of collagen types I and III. Keloid fibroblasts have been shown to make elevated levels of transforming growth factor beta (TGF-beta), a growth factor known to promote extracellular matrix production and fibrosis. Thus, the pathophysiology underlying keloid formation may be driven by the biological activity of TGF-beta. Tamoxifen, a synthetic, nonsteroidal antiestrogen has been shown to inhibit keloid fibroblast proliferation and decrease collagen production. The purpose of this study was to determine if a mechanism by which tamoxifen decreases keloid collagen production is through a downregulation of TGF-beta. Through a luciferase TGF-beta bioassay we found that 4 microM of tamoxifen generated a 49% reduction in total TGF-beta activity and 8 microM generated an 85% reduction compared with controls. Thus we propose that one of the mechanisms by which tamoxifen decreases keloid fibroblast collagen synthesis is by decreasing TGF-beta production.

Skin disorders in black children

Recently, progress and developments have been made in six skin conditions relevant to black children. Infantile acropustulosis may either be idiopathic or may be a sequela of scabies in young infants. The approach to small- or medium-sized congenital melanocytic nevi in black children must be different because the risk for malignant transformation into melanoma is exceedingly small. Keloids and hypertrophic scars in children are effectively treated with silicone gel sheeting. Tinea capitis caused by Trichophyton tonsurans remains to be a very common infection among black children. The newer systemic antifungal agents have no significant advantage over griseofulvin. Hair problems resulting from grooming practices or hair styling are preventable. For postinflammatory hyperpigmentation, azelaic acid holds promise.

Plastic surgery research

Several areas of plastic surgery research, both in and out of the basic science laboratory, have been highlighted. Progress is being made in our ability to produce biologic structures to replace destroyed or damaged ones in vitro, our ability to manipulate the genetic structure of cells, and our ability to define and potentially manipulate the wound healing process in normal and abnormal healing states. More is also being learned about the biology of nerve repair, the physiologic response to silicone implants, and the mechanism of reperfusion injury. Virtual surgery may become a major part of the planning, performance, and teaching of surgical procedures in the future. Outcomes need to be better defined to prove the value of what plastic surgeons do to increasingly skeptical third parties, and progress is being made in this area as well. These areas represent only a few aspects of what is new in plastic surgery research, but they at least provide a window into the field and demonstrate the increasing sophistication of work being done in all areas. This work, as well as work in other areas, will undoubtedly affect clinical practices in the near future.

Deep fungal infections in the tropics

Although tropical deep fungal infections are uncommonly identified in North America, these disorders are a diagnostic and therapeutic challenge to the clinician. Presented in this article is information on the management of patients suffering from mycetoma, chromomycosis, African histoplasmosis, or keloidal blastomycosis.