Clinical Evaluation Of 5-aminolevulinic Acid Photodynamic Therapy For The Treatment Of Moderate To Severe Acne Vulgaris

Background: Acne vulgaris is a common chronic inflammatory skin disease of the pilosebaceous follicle.Among them,the patients of moderate and severe acne vulgaris mainly manifested by pustules,cysts and nodules are more likely to form pigmentation and acne scar,which will affect the appearance of patients and have a great impact on the psychology.The treatment protocols of moderate to severe acne vulgaris are limited.Oral retinoids have teratogenic side effects,and antibiotics are susceptible to resistance.In recent years,photodynamic therapy with 5-aminolevulinic acid(ALA-PDT)for the treatment of moderate to severe acne vulgaris has become a new research hotspot due to its advantages of simple operation,mild adverse reactions and repeatable treatments.Objective: The purpose of this study is to evaluate the clinical efficacy and safety of ALA-PDT for the treatment of moderate to severe acne vulgaris.Methods: The moderate to severe acne vulgaris patients meeting the diagnostic criteria were treated with ALA-PDT.Freshly prepared 5% ALA was applied to face and/or neck for 1 hour's incubation with subsequent illumination by a red LED device at a distance of 10-20 cm.A power density of 60-100mw/cm2 was delivered for 20 minutes(the initial treatment started from 60 m W/cm2 for 5 minutes of irradiation,then it increased to 80 m W/cm2 for 15 minutes.The second to fourth treatment was started with 80 m W/cm2 for 5 minutes,and then increased to 100 m W/cm2 for 15 minutes).All patients finished 3 to 4 sessions treatment of ALA-PDT at 7 to 10 days intervals.Before each treatment(T0?AT1?AT2?AT3)and follow-ups at 1,2,3 months after last session(FU1?FU2?FU3),acne lesions were recorded to evaluate the efficacy,respectively.Meanwhile,non-invasive detections were taken by skin moisture and oil tester and VISIA detector.Adverse events and the measures taken were asked and recorded.SPSS 22.0 software was used for statistical analyses,and p<0.05 was considered statistically significant.Results: A total of 116 cases of moderate or severe acne vulgaris patients were included.(1)The efficiencies of all patients at AT1 and AT2 were 5.2% and 29.3%.For patients of PDT3,the efficiencies at FU1-3 were 59.4%,66.7% and 78.3%,respectively.For patients of PDT4,the efficiencies at AT3 and FU1-3 were 51.3%,63.6%,76.5% and 85.7%,respectively.(2)At FU1-3,there was no significant difference in efficacy between PDT3 and PDT4(p>0.05).(3)At the follow-ups after last session of treatment,there was no difference in the efficacy of PDT3 patients at each viewing point(p>0.05),however,the efficacy of PDT4 patients showed an increasing trend(G=0.480,p=0.004).(4)At FU2 and FU3,it was observed that the severity of acne vulgaris was correlated with the treatment effect,that is,the more severe the acne vulgaris was,the higher the efficacy was(FU2: G=0.444,p=0.009;FU3: G=0.520,p=0.011).(5)At FU1-3,the acne lesions were from mild to severe,i.e.,comedos,papulae,pustules and cyst nodules,which were correlated with the treatment effect.The more severe the acne lesions were,the higher the efficacy was(FU1: G=0.354,p=0.000;FU2: G=0.474,p=0.000;FU3: G=0.397,p=0.000).(6)Seventeen patients were followed up for 12 months,it showed that 9 patients were able to maintain ?90% improvement rate,and the number of rashes and skin lesions of most of the remaining patients were significantly reduced compared with the previous ones.(7)The moisture content,oil content,ultraviolet ray spots,brown spots,red areas,and purple texture of the skin of 18 patients of PDT3 were measured.No statistically significant differences were found among the indicators before and after treatment(p>0.05).(8)The adverse reactions of ALA-PDT included local burning sensation,mild pain sensation,mild edema erythema,reactive acne vulgaris,pigmentation,etc.,which can be subsided after symptomatic treatment.Conclusion: The efficiencies of ALA-PDT for the treatment of moderate to severe acne vulgaris at follow-ups of 1,2,3 months after last session were 59.4%-85.7%.No significant changes were observed in skin physiological function indexes,and adverse reactions could be subsided after symptomatic treatments.ALA-PDT is a safe and effective method for the treatment of moderate to severe acne vulgaris.