This month's news from across the specialty
What's hot
March 1, 2020
In this monthly column, members of Dermatology World's Editorial Advisory Workgroup identify exciting news from across the specialty.
There are relationships of psoriasis lesions with candida, staph aureus, and now bacteriophages. Our understanding of the interplay between our skin and the microbiome is greatly expanding. This movement is being supported by improved genetic methods that permit the identification and relative quantification of very small amounts of DNA. The geographic expanse of our cutaneous anatomy is being explored to define the microbiome as a complex and extensive ecosystem with energy pyramids like prairies and rain forests.
A recent study described the relative populations of bacteriophages in psoriasis patients comparing lesional skin to healthy skin from contralateral sites, and healthy skin from unaffected family members (doi:10.1016/j.jid.2019.05.023). This study first mirrors multiple previous studies that described the dysbiosis of the bacterial populations in psoriasis lesions. New in this work, the bacteriophage populations are also found to be distinct between lesional, non-lesional, and unaffected family samples. Like many great experiments, this insight appears obvious when the study is completed — as bacteriophages selectively target individual species of bacteria. In the setting of persisting inflammatory cycles — where the end of the cycle is more important than the beginning — these microbiome populations may inform treatment decisions in treatment refractory psoriasis. The authors also propose and have applied for a patent for future psoriasis treatments that deliver bacteriophages to target specific bacteria species.
Behçet’s syndrome is a multisystem vasculitis that is as vexing to diagnose as it is to treat. The long list of therapeutic options at first glance offers hope in the fight against a disease well known for painful recurrent oral and genital ulcerations. However, we know all too well that this is a testimony to the lack of reliable options.
Apremilast, a phosphodiesterase 4 inhibitor, was approved by the FDA in 2019 for oral ulcers associated with Behçet’s syndrome. This approval stemmed from the results of a randomized, double-blind, placebo-controlled, phase 3 trial that was conducted in 53 centers across 10 countries from 2014 to 2017 (N Engl J Med. 2019; 381:1918-28). 207 biologic naïve patients who had Behçet’s syndrome with active oral ulcers, but no major organ involvement, received either apremilast 30mg or placebo, administered orally, twice daily for 12 weeks, followed by a 52-week extension phase.
The primary endpoint was the total number of oral ulcers during the 12-week placebo-controlled period: 129.5 for apremilast versus 221.1 for placebo (least-squares mean difference, -92.6; 95% CI -130.6 to -54.6; P<0.001). Six weeks into the trial, 30% of patients treated with apremilast were free of oral ulcers and remained ulcer free for at least six more weeks, versus only 5% of the placebo group. By week 12, 53% in the apremilast group versus 22% in the placebo group were clear of oral ulcers. Apremilast treatment was also associated with decreased oral ulcer pain and improvement in quality of life. There was a trend toward decreased genital ulcers in the apremilast group, but the trial was not designed to detect a significant change in this measure.
Side effects with apremilast treatment included diarrhea, nausea, and headache. There was no evidence of worsening uveitis or other major organ flare with apremilast treatment. How apremilast performs in real-world treatment, and in patients with severe systemic involvement, remains to be seen.
Similar to the search of Ponce De Leon’s fountain of youth, there is a constant search for the “latest and greatest” technology to fend off the signs of facial aging. Thread lifts have started to gain attention yet again as an option for redraping the skin. Unlike their permanent predecessor (Aptos threads) and those requiring both entry and exit points (Silhouette suture), PDO is a synthetic polymer of p-dioxanone that is absorbed via hydrolysis and has a single site of entry. These threads have adherent wedge-shaped cones that, once anchored in place, have a very high tensile strength with minimal tissue reactivity. Upon appropriate placement they can improve the descent of facial laxity.
Although widely mentioned in the lay press, there is very little published in the scientific literature about the product, the technique, efficacy, and longevity, and to date, they are solely approved for soft tissue wound approximation. Theoretically, the aesthetic purpose of the barbed suture is to maintain tissue tension without slipping, lifting the cheek and jowl areas. This ambulatory procedure requires insertion of the thread protected by an overlying cannula; once in the proper vector and subdermal space, the cannula is removed and the thread remains intact in the tissue. The overlying skin is digitally massaged so that the cogs can adequately adhere to the dermis and the residual tail of the thread is cut so that it is buried subdermally not extruding from the skin. Threads are available in multiple lengths and diameters and the number used at one time is contingent upon facial anatomy and realistic expectations of moderate improvement of laxity. Post-operative instructions are limited to restriction of exertional activity. There is much technique variability and reported adverse events include ecchymosis and edema. There is mention of dimpling.
However, what is not well discussed is the fate of the redundant skin that has been repositioned. Histologically, at three months in the guinea pig model, the thread is enveloped by a homogenous fibrous capsule and the cog induces fibrosis with an accompanying inflammatory cell aggregation. This reaction pattern increased vascular structures, dermal thickness consisting of collagen Type I. By seven months, the synthetic threads were difficult to locate, and the neo-collagenases improved the overall skin texture and tautness (Derm Surg. 2017; 43:74-80). The preliminary results demonstrating an immediate cutaneous lift seem to be impressive; what remains to be evaluated is if this is a consequence of edema and if the clinical results can withstand the scrutiny of time.
Contact dermatitis, both irritant and allergic, is very common in health care workers. Hand dermatitis is a frequent occupational problem in hospital workers who wear occlusive gloves, wash their hands frequently, and come in contact with many allergens. Classically, gloves have been felt to be a common cause of contact dermatitis in health care workers. Two recent articles in Dermatitis point to hand hygiene, disinfectants, and scrubs as important potential sources of allergens. Hand hygiene is important in the fight against hospital acquired infections. Hand hygiene can be with waterless cleansers, water-needed soaps, surgical scrubs, and other disinfectants. The most common allergens in waterless skin soaps were found to be fragrances, tocopherol, and sodium benzoate. Fragrances were also a top allergen in water-needed skin soaps, as were chloroxylenol, propylene glycol, and cocamidopropyl betaine. Skin disinfectant allergens were led by chlorhexidine, cocamide diethanolamine, and fragrance (2019. Nov/Dec. (6): 336-41). In a related article focusing on allergic contact dermatitis to operating room scrubs and disinfectants, several allergens were noted including cocamide diethanolamide, fragrance, lanolin, propylene glycol, alkyl glucosides, and sorbic acid derivatives (2019. Nov/Dec (6): 363-70). As physicians, we need to keep in mind the many allergens that health care workers frequently encounter as we evaluate them for occupationally related dermatitis. In addition to gloves, the many types of products used in the important practice of hand hygiene are potential allergens. Patch testing and the use of products with low allergen content, as noted in these articles, are useful in the management of these patients.
