Research Article
Comparing the Efficacy of Intra-dermal Platelet Rich Plasma (PRP) Injection versus 35% Trichloroacetic Acid (TCA) for Treatment of Atrophic Acne Scars
- Shaymaa El Mongy Mohamed
- Rania Elsayed Hamed Ali Omar *
- Fatma Faisal El Dakrory
Dermatology, Andrology & STDs Department, Faculty of Medicine, Mansoura University, Egypt.
*Corresponding Author: Rania Elsayed Hamed Ali Omar, Dermatology, Andrology & STDs Department, Faculty of Medicine, Mansoura University, Egypt.
Citation: S.E.M. Mohamed, R.E.H.A. Omar, F.F.E. Dakrory. (2024). Comparing the Efficacy of Intra-dermal Platelet Rich Plasma (PRP) Injection versus 35% Trichloroacetic Acid (TCA) for Treatment of Atrophic Acne Scars. Dermatology Research and Reports, BioRes Scientia Publishers. 3(1):1-11. DOI: 10.59657/2993-1118.brs.24.011
Copyright: © 2024 Rania Elsayed Hamed Ali Omar, this is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Received: August 06, 2023 | Accepted: August 28, 2023 | Published: January 02, 2024
Abstract
Background: Atrophic acne scars are a common concern among individuals of all ages and skin types, impacting both appearance and self-esteem. Platelet-rich plasma (PRP) and trichloroacetic acid (TCA) have gained attention as potential treatments for atrophic acne scars due to their regenerative and collagen-stimulating properties.
Aim of the Work: This study aims to compare the efficacy of intra-dermal PRP injections and 35% TCA in treating atrophic acne scars.
Patients and Methods: A randomized controlled trial involving 60 participants with atrophic acne scars was conducted. The participants were divided into two groups: the first group received intra-dermal PRP injections, while the second group received 35% TCA treatment. The efficacy of both treatments was evaluated based on scar improvement, patient satisfaction, and adverse effects.
Results: The study findings indicate that both PRP injections and TCA treatment significantly improved the appearance of atrophic acne scars. The application of TCA resulted in a significantly higher percentage of scar improvement compared to PRP. Complications were minimal, with a slightly higher incidence observed in the TCA group. These results support the notion that TCA is more effective than PRP in improving the appearance of atrophic acne scars. The findings also highlight the overall safety of both treatments, although TCA carries a slightly higher risk of complications.
Conclusion: This study provides evidence supporting the superior efficacy of TCA over PRP in treating atrophic acne scars. It emphasizes the importance of considering patient satisfaction, demographic factors, and potential complications when choosing between these treatment options.
Keywords: intra-dermal platelet rich plasma (PRP); trichloroacetic acid (TCA); atrophic acne scars
Introduction
Acne Vulgaris (AV), is a long-term skin disease that occurs when hair follicles are clogged with dead skin cells and oil from the skin. It is characterized by blackheads or whiteheads, pimples, oily skin, and possible scarring [1]. Acne sequelae differ according to the duration of inflammation and the site of damage whether dermal or epidermal. Purely epidermal damage is followed by erythema or dyschromia, whereas dermal damage is the actual cause of atrophic scars of different shapes [2]. Scarring occurs in almost 95% of patients with acne. Unfortunately, the atrophic type is often a permanent complication that affects the psychological status of patients negatively [3]. Atrophic acne scars can result from inflammatory skin disease causing sufficient damage to the epidermis and to the dermal collagen. Facial scars resulting from any etiologies are associated with psychological trauma and loss of self-esteem [4]. The main morphological types of atrophic postacne scars are ice pick pitted scars, superficial or deep boxcar scars, and rolling scars. Treatment of each morphological scar type varies, and although one scar type responds to some treatment modality, the same treatment option may not be necessarily effective in other type of scars [5]. A chemical peel is a quick outpatient procedure that can be used to treat acne scarring. Trichloroacetic acid was used conventionally over years in different strengths ranging from 35% to 100% in various application methods [6].
However, these chemical peels usually work best for macular scars, have limited use for deeper atrophic scars, and should be used cautiously in darker-skinned patients because of the potential for pigmentary alterations. Deep chemical peels have fallen out of favor for the treatment of acne scars because of their significant side effect profile, such as dyschromia and scarring [7]. Platelet Rich Plasma (PRP) is a blood product with a high platelet and a normal plasma fibrinogen level. Given the effective factors of PRP in repairing damaged tissues, its application in the field of regenerative medicine has widely been interested over the last three decades [8]. Autologous PRP injection is a safe process, applicable even at outpatient clinic, repeatable and reproducible technique that doesn't require post injection precautions such as avoidance of sun exposure which may interfere with patient usual habits like laser therapy or dermabrasion [9].
Aim of the Work
The aim of this study was to compare the safety and the efficacy of intra-dermal platelet rich plasma (PRP) versus 35% trichloroacetic acid (TCA) for treatment of atrophic post-acne scars.
Patients and Methods
Study design: This study is a prospective comparative study.
Settings (Locality) and duration: Outpatient clinic of Dermatology, Andrology& STDs Department, Mansoura University hospital in the period between January 2022 and December 2022.
Study subjects: The study included 60 patients with atrophic facial acne scars. According to the application of the treatment regimen; we had two groups as follows: Group A:This group (30 patients) were treated with 35% TCA and group B: This group (30 patients) were treated with PRP injection.
Inclusion criteria
Both genders were included, age ≥ 18 years, patients with atrophic facial acne scars and skin types ranging from II to IV.
Exclusion criteria
Receiving any treatment in the last 6 months for their scars, active acne, skin types V and VI, systemic isotretinoin in the past 6 months, history of keloid, history of facial surgery or procedure for scar, pregnancy and lactation, systemic diseases that can impair healing (e.g., Renal and hepatic diseases) and patients using non-steroidal anti-inflammatory drugs and anticoagulant drugs such as aspirin.
Ethical considerations: Informed consent was taken from all patients included in the Study, all precautions were taken for the privacy of patients, all the results were used only for scientific purposes, this study was taken out after agreement of the local ethical committee, acceptance of the IRB of Mansoura Faculty of Medicine was obtained before starting of the research and code number; MS.22.01.1823
Methods
Complete history taking: Name, age, sex, duration of the lesion, progression of the lesion, previous medication or intervention, family history of similar conditions and site of the scar.
Clinical examination
General and Dermatological examination:
General examination: Clinical examination of patients for any signs of systemic diseases.
Dermatological examination: Determination of acne scar severity was done using global acne scar Grading system [10]. The patients were informed about the nature of the procedures, number of sessions and expected side effects of the procedures.
Photography: All photographs were taken for the face using a digital camera (Sony Alpha A6400) using fixed settings, lighting, and patient positioning (front and profile views of the face) for standardization. Photographs were taken before the sessions. Also were taken before and after each session and after the follow up period. Photographic evaluation was done with the same camera by 3 dermatologists.
Treatment regimen
Trichloroacetic acid peel: the face was treated with one pass of 35% TCA soaked gauze, the end point of treatment was the appearance of white frosting,some Patients experienced a stinging and burning sensation, patients were advised to rinse the face with water until clearance of burning sensation, patients were advised to close their eyes during the application of treatment and patients were advised to avoid sun exposure after the session.
Platelet rich plasma regimen
Preparation of PRP: PRP was prepared by double spin method for each session, 10ml blood was withdrawn from the antecubital vein under complete aseptic conditions in 5cm sterile tube prefilled with 3ml of acid citrate dextrose anticoagulant with (1: 10) ratio (anticoagulant: blood), first centrifugation was performed at 1500g for 5min, both Buffy coat and plasma layer was taken for further centrifugation and red cell sediment was discarded, second centrifugation was performed at 4000g for 10min, resulting in the formation of platelet poor plasma above platelet rich zone at the bottom, platelet Poor Plasma was removed and discarded leaving behind a solution of 2ml PRP and then PRP solution was injected.
Injection: After cleaning the face with spirit, it was anesthetized using a topical anesthetic cream for about 45 minutes, PRP was injected intradermally through a 30G sterile disposable needle (insulin syringe) deep to each scar on both cheeks, the amount injected was sufficient to elevate the scar and the end point was taken as the elevation of scar, total amount injected was 3-4 mL depending on the number of scars, after injecting, the site was gently massaged and compressed for a few seconds to control the bleeding and the patients were advised to use topical antibiotic after the session.
Treatment duration and follow up: All patients were exposed to four treatment sessions at 4 week’s intervals, when there was complete cure before completion of 4sessions, treatment was stopped, the cases were followed for three months to monitor the improvement of the scar and the side effects of TCA when developed.
Statistical Analysis: The collected data was revised, coded, and tabulated using Statistical package for Social Science (IBM Corp. Released 2017. IBM SPSS Statistics for Windows, Version 25.0. Armonk, NY: IBM Corp.). Data were presented and suitable analysis was done according to the type of data obtained for each parameter.
Normality of data: Shapiro-Wilk test was done to test the normality of data distribution.
Descriptive statistics: Mean, Standard deviation (± SD), median, minimum and maximum for distributed numerical data and frequency and percentage of non-numerical data.
Results
Figure 1: Study flow chart.
"The study included 60 patients (23 males, 37 females) with atrophic acne scars, who met the inclusion criteria. They were randomly assigned to two groups: Group A (n=30) received 35% TCA treatment, and Group B (n=30) received PRP injection.
Table 1: Complications among patients with atrophic acne scars.
| All cases n=60 | ||
| № | % | |
| Complication | ||
| No | 58 | 96.7 |
| Yes | 2 | 3.3 |
Table 2: Demographic data among patients treated with TCA and PRP
| TCA n=30 | PRP n=30 | Test (p) | |||
| № | % | № | % | ||
| Sex | |||||
| Male | 12 | 40.0 | 11 | 36.7 | x2=0.071 p=0.791 |
| Female | 18 | 60.0 | 19 | 63.3 | |
| Age (years) | |||||
| Mean ± SD. | 27.70 ± 9.06 | 27.03 ± 9.19 | t=0.283 p=0.778 | ||
| Median (Range) | 24.50 (16.0–50.0) | 24.50 (13.0–45.0) | |||
| Marital status | |||||
| Married | 18 | 60.0 | 18 | 60.0 | x2=0 p=1.000 |
| Single | 12 | 40.0 | 12 | 40.0 | |
SD. Standard deviation, Range: Min. – Max; X2, chi square test; t Student-t test; p<0>
Table 3: Baseline scar score difference between patients treated with TCA and PRP
| Score of scars | TCA n=30 | PRP n=30 | Test (p) |
| Before treatment | |||
| Mean ± SE. | 3.33 ± 0.17 | 3.0 ± 0.18 | U=357.0 p=0.139 |
| Median (Range) | 4.0 (1.0 – 4.0) | 3.0 (1.0 – 4.0) |
SE. Standard error, Range: Min. – Max; U, Mann-Whitney; p<0>
Table 4: Scar score among patients treated with TCA and PRP after therapy
| Score of scars | TCA n=30 | PRP n=30 | Test (p1) |
| Before treatment | |||
| Mean ± SE. | 3.33 ± 0.17 | 3.0 ± 0.18 | U=357.0, p1=0.139 |
| Median (Range) | 4.0 (1.0 – 4.0) | 3.0 (1.0 – 4.0) | |
| After treatment | |||
| Mean ± SE. | 1.87 ± 0.16 | 2.47 ± 0.18 | U=598.0, P2=0.020* |
| Median (Range) | 2.0 (0.0 – 3.0) | 2.0 (0.0 – 4.0) | |
Test P2 | Z=0.0 P3<0> | Z=0.0 P4<0> |
SE. Standard error, Range: Min. – Max. U Mann-Whitney; Z: Wilcoxon test; p<0>
Figure 2: Line chart for scar score among patients treated with TCA and PRP.
Patients treated with TCA demonstrated a higher percent improvement in scar scores compared to the PRP group.
Table 5: Percent improvement of scar score among patients treated with TCA and PRP
| Score of scars | TCA n=30 | PRP n=30 | Test (p) |
| Percent improvement | |||
| Mean ± SE. | 46.39 ± 3.80 | 17.78 ± 4.26 | U=148.5 p<0> |
| Median (Range) | 50.0 (0.0 – 100.0) | 0.0 (0.0 – 100.0) |
SE. Standard error, Range: Min. – Max., U, Mann-Whitney; *: Significant <0>
Figure 3: Boxplot for percent improvement of scar score among patients treated with TCA and PRP.
Complications were observed in two TCA-treated cases, while there were no complications in the PRP group.
Table 6: Complications among patients treated with TCA and PRP
| TCA n=30 | PRP n=30 | Test (p) | |||
| № | % | № | % | ||
| Complication | |||||
| No | 28 | 93.3 | 30 | 100.0 | x2=2.069 p=0.492 |
| Yes | 2 | 6.7 | 0 | 0.0 | |
X2, chi square test; p<0>
Patient satisfaction was significantly higher in the TCA group compared to the PRP group.
Table 7: Patient satisfaction among patients treated with TCA and PRP
| TCA n=30 | PRP n=30 | Test (p) | |||
| № | % | № | % | ||
| Patient satisfaction | |||||
| No | 3 | 10.0 | 22 | 73.3 | x2=24.754, p<0> |
| Yes | 27 | 90.0 | 8 | 26.7 | |
X2, chi square test; p<0>
Figure 4: Column chart for patient satisfaction among patients treated with TCA and PRP.
No significant associations were found between the percent improvement of scar scores and demographic data, course, complications, or patient satisfaction in the TCA group.
Table 8: Association between percentage of clinical improvement of scar score and demographic data in patients treated by TCA.
| % Improvement of scar score | Test (p) | |||
| Mean ± SE. | Median | Range | ||
| Sex | ||||
| Male, n=12 | 40.28 ± 4.68 | 50.0 | 0.0 – 50.0 | U=127.0, p=0.439 |
| Female, n=18 | 50.46 ± 5.41 | 50.0 | 25.0 – 100.0 | |
| Marital status | ||||
| married, n=18 | 44.91 ± 5.27 | 50.0 | 0.0 – 100.0 | U=117.5, p=0.692 |
| single, n=12 | 48.61 ± 5.51 | 50.0 | 25.0 – 100.0 | |
| Special habit | ||||
| No, n=26 | 48.72 ± 3.89 | 50.0 | 25.0 – 100.0 | U=32.5, p=0.245 |
| Yes, n=4 | 31.25 ± 11.97 | 37.50 | 0.0 – 50.0 | |
SE. Standard error, Range: Min. – Max; U, Mann-Whitney.
Table 9: Association between percentage of clinical improvement of scar score and course in patients treated by TCA.
| % Improvement of scar score | Test (p) | |||
| Mean ± SE. | Median | Range | ||
| Course | ||||
| Progressive, n=11 | 46.97 ± 2.03 | 50.0 | 33.33 – 50.0 | U=90.5, p=0.553 |
| Stationary, n=19 | 46.05 ± 5.96 | 50.0 | 0.0 – 100.0 | |
SE. Standard error, Range: Min. – Max; U, Mann-Whitney.
Table 10: Association between percentage of clinical improvement of scar score and complications in patients treated by TCA.
| % Improvpement of scar score | Test (p) | |||
| Mean ± SE. | Median | Range | ||
| Complication | ||||
| No, n=28 | 46.73 ± 4.05 | 50.0 | 0.0 – 100.0 | U=24.5, p=0.777 |
| Yes, n=2 | 41.67 ± 8.33 | 41.67 | 33.33 – 50.0 | |
SE. Standard error, Range: Min. – Max; U, Mann-Whitney.
Table 11: Association between percentage of clinical improvement of scar score and patient satisfaction in patients treated by TCA.
| % Improvement of scar score | Test (p) | |||
| Mean ± SE. | Median | Range | ||
| Patient satisfaction | ||||
| No, n=3 | 16.67 ± 8.33 | 25.0 | 0.0 – 25.0 | U=77.0, p=0.005* |
| Yes, n=27 | 49.69 ± 3.63 | 50.0 | 25.0 – 100.0 | |
SE. Standard error, Range: Min. – Max; U, Mann-Whitney. *: Significant <0>
Clinical Results
Group A: Treated with 35% TCA
Figure 5: A 28 years old female with atrophic acne scars.
A: Before treatment, Goodman and Baron Global classification of acne scars (4).
B: At the end of follow up with good improvement, Goodman and Baron classification (2).
Figure 6: A 24 years old female with atrophic acne scars.
A: Before treatment, Goodman and Baron Global classification of acne scars (4).
B: At the end of follow up with excellent improvement, Goodman and Baron classification (2).
Group B: Treated with PRP injection
Figure 7: A 45 years old female with atrophic acne scars.
A: Before treatment, Goodman and Baron Global classification of acne scars (4).
B: At the end of follow up with moderate improvement, Goodman and Baron classification (3).
Figure 8: A 37 years old male with atrophic acne scars.
A: Before treatment, Goodman and Baron Global classification of acne scars (3).
B: At the end of follow up with moderate improvement, Goodman and Baron classification (2).
Discussion
Atrophic acne scars are a common problem affecting individuals of all ages and skin types. These scars can have a significant impact on the appearance and self –esteem of individuals, leading them to seek treatment options to improve their appearance [11]. Autologous PRP provided a full array of potential bioactive growth factors and chemokines released on platelet activation, which aid in quick wound healing and actively reduce atrophic acne scarring [12]. Chemical peeling is a quick outpatient procedure that can be used to treat acne scarring. Trichloroacetic acid was used conventionally over years in different strengths ranging from 35% to 100% in various application methods [6]. The aim of present study is to compare the efficacy of intradermal PRP injection versus 35% TCA for the treatment of post acne atrophic scar. This study was carried out on 60 patients with atrophic acne scars. All patients were recruited from those attending the outpatient clinic of Dermatology, Andrology &STDs Department, Mansoura University Hospitals, Mansoura, Egypt. The patients were divided into two groups; The first group was treated with PRP injection, and the second group was treated with 35% TCA.
In the current study, Scar score after treatment improved significantly at both groups, However, there was a statistically significant difference of acne scar grade post treatment between the two groups. The TCA group showed significantly better score than PRP group (mean =1.87 versus 2.47, P1= 0.020). Our study found that the application of TCA resulted in a statistically significant higher percent improvement in scar score compared to PRP (46.4% versus 17.8%, P <0>25% improvement (fair response), despite the overall clinical improvement being more than 50%, which is consistent with the results of our study [15]. noticed improvement of acne scarring by PRP intradermal injection, while using PRP for skin rejuvenation. They were the first to recommend further trials to examine the benefit of injecting PRP in acne scars, which support the results of our study [6]. found that intra-dermal PRP was significantly better at 12 and 24 weeks after treatment as compared to 50% TCA applied by CROSS technique, and it was seen that mean scar score at 12 weeks was 14.15 ± 3.05 vs. 17.57±4.51 (p <0>
According to a study done by [16], they compared PRP with 100% TCA applied by CROSS technique. They further found that, in grade I acne scar, there were no cases, in grade 2, efficacy of PRP vs. 100% TCA was 40% vs. 33%, in grade 3 it was 33% vs. 40%, and in grade 4, it was 26.7
Conclusion
Both PRP and TCA are effective treatment options for reducing the severity of atrophic acne scars. However, TCA was found to be more effective than PRP in producing a greater percent improvement of scar score. Furthermore, patient satisfaction was found to be an important outcome measure to consider when evaluating treatment effectiveness.
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