Light and laser therapy for acne: sham or science? facts and controversies

Acne Treatment With Light Absorbing Gold Microparticles and Optical Pulses: An Open-Label European Multi-Centered Study in Moderate to Moderately Severe Acne Vulgaris Patients

BACKGROUND AND OBJECTIVE

Recently, a novel acne treatment based on selective photothermolysis of pilosebaceous units with follicular delivery of inert gold microparticles as an exogenous chromophore and diode laser pulses has been developed. To evaluate the efficacy and safety of a single monotherapy treatment regimen with gold microparticles and diode laser exposure in patients with moderate and moderately severe acne. Further, to evaluate the added benefit of a second treatment regimen combined with pharmaceutical acne treatment in patients with inadequate initial response.

MATERIALS AND METHODS

Patients with moderate and moderately severe facial acne were recruited in this open-label, pilot study. A single treatment regimen consisted of three weekly facial treatments with topically applied gold microparticles and diode laser pulses. Outcome measures were the proportion of patients with ≥40% improvement in number of acne lesions (weighted lesion count [WLC]) at 12 weeks (single treatment regimen, primary outcome measure), 24, and 36 weeks from baseline (two treatment regimens), safety, and patient satisfaction.

RESULTS

A total of 28 patients were enrolled in the study (18 males, 10 females, 19 patients with moderate acne severity, 9 with moderately severe, mean age: 19.8 years). Twenty-five patients underwent analysis for outcome measures. After a single monotherapy treatment regimen, 76% patients (19/25) achieved ≥40% reduction in WLC (mean WLC reduction: 63%; SD: 13%). Of the patients undergoing two treatment regimens (n = 9 patients), 56% experienced a reduction in acne lesion burden (WLC) ≥40% at 24 weeks and 89% 36 weeks post-baseline. Mean pain score was 4.0 (SD: 1.3), and transient erythema and perifollicular edema were commonly noted after treatment. Most patients (81%) were either "satisfied" or "very satisfied" with the treatment.

CONCLUSION

Acne therapy based on selective photothermolysis with gold microparticles shows promise and may be used in treatment of moderate to moderately severe acne. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Do Dermatologic Diagnosis Change in Hot vs. Cold Periods of The Year? A Sub-Analysis of the DIADERM National Sample (Spain 2016)

BACKGROUND

Knowledge of seasonal variation of cutaneous disorder may be useful for heath planning and disease management. To date, however, descriptions of seasonality including all diagnoses in a representative country sample are very scarce.

OBJECTIVES

To evaluate if clinical dermatologic diagnosis in Spain change in the hot vs. cold periods.

MATERIALS AND METHODS

Survey based on a random sample of dermatologists in Spain, stratified by area. Each participant collected data during 6 days of clinical activity in 2016 (3 in the cold period of the year, 3 in the hot period). Clinical diagnoses were coded using ICD-10.

RESULTS

With a 62% response proportion, we got data on 10999 clinical diagnoses. ICD-10 diagnostic groups that showed changes were: other benign neoplasms of skin (D23), rosacea (L71) and other follicular disorders (L73), which were more common in the hot period and acne (L70) which was more frequent in the cold period. We describe differences in the paediatric population and in private vs. public practice. Some of these differences might be associated to differences in the population demanding consultations in different periods.

CONCLUSIONS

The frequency of most clinical diagnosis made by dermatologists does not change over the year. Just a few of the clinical diagnoses made by dermatologists show a variation in hot vs. cold periods. These variations could be due to the diseases themselves or to seasonal changes in the demand for consultation.

Topical, Biological and Clinical Challenges in the Management of Patients with Acne Vulgaris

Acne vulgaris is one of the most common chronic inflammatory skin disorders among adolescents and young adults. It is associated with substantial morbidity and, rarely, with mortality. The exact worldwide incidence and prevalence are currently unknown. Current challenges involve improving understanding of the underlying pathophysiology of acne vulgaris and developing a practical treatment consensus. Expert panel discussions were held in 2013 and 2014 among a group of scientists and clinicians from the Omani and United Arab Emirate Dermatology Societies to ascertain the current optimal management of acne vulgaris, identify clinically relevant end-points and construct suitable methodology for future clinical trial designs. This article reviews the discussions of these sessions and recent literature on this topic.

Acne Treatment Based on Selective Photothermolysis of Sebaceous Follicles with Topically Delivered Light-Absorbing Gold Microparticles

The pathophysiology of acne vulgaris depends on active sebaceous glands, implying that selective destruction of sebaceous glands could be an effective treatment. We hypothesized that light-absorbing microparticles could be delivered into sebaceous glands, enabling local injury by optical pulses. A suspension of topically applied gold-coated silica microparticles exhibiting plasmon resonance with strong absorption at 800 nm was delivered into human pre-auricular and swine sebaceous glands in vivo, using mechanical vibration. After exposure to 10-50 J cm(-2), 30 milliseconds, 800 nm diode laser pulses, microscopy revealed preferential thermal injury to sebaceous follicles and glands, consistent with predictions from a computational model. Inflammation was mild; gold particles were not retained in swine skin 1 month after treatment, and uptake in other organs was negligible. Two independent prospective randomized controlled clinical trials were performed for treatment of moderate-to-severe facial acne, using unblinded and blinded assessments of disease severity. Each trial showed clinically and statistically significant improvement of inflammatory acne following three treatments given 1-2 weeks apart. In Trial 2, inflammatory lesions were significantly reduced at 12 weeks (P=0.015) and 16 weeks (P=0.04) compared with sham treatments. Optical microparticles enable selective photothermolysis of sebaceous glands. This appears to be a well-tolerated, effective treatment for acne vulgaris.