unfortunately , there is no definite treatment for this disease . despite self - healing nature of this disease , the scar that remains due to the disease can induce many psychosocial problems for patients . cutaneous leishmaniasis scar is an atrophic scar that is formed due to dermal atrophy and destruction of collagen following acute inflammatory reaction . it is shown that application of 65 and 100% trichloroacetic acid ( tca ) can be used for the treatment of atrophic acne scars . one of the other methods that are used extensively for treatment of the atrophic scars , such as those formed due to acne or chicken pox , is high - energy pulsed or scanned co2 laser that can abrade epidermis in one pass . in one study that was performed in 30 patients with acne scar , chicken pox scar and atrophic scar due to heart surgery , 60% improvement in scar appearance was observed following short - pulse and continuous co2 laser . although co2 laser can effectively repair the atrophic scars , some side effects the treatment causes , such as prolonged healing time , resistant erythema and hypopigmentation in 20% of treated cases , should also be considered . we designed the following study to evaluate the effect of focal peeling with tca versus co2 laser in treatment of leishmaniasis scar . this study was a randomized controlled clinical trial that was performed in 92 patients , aged 1850 years , with atrophic leishmaniasis scar . patients with chronic diseases , immunodeficiency , history of hypertrophic scar or keloids , history of isotretinoin use is the last 1 year , pregnancy or lactation were included . , the scar site was first defatted with acetone and then 50% tca was applied to the scar site using cotton applicator . after whitening of the scar , the acid was neutralized using water and petrolatum was then applied . patients were then instructed to apply sunscreen at the morning and noon and hydroquinone 4% cream at the nights . patients were followed every 2 weeks for 3 months and then at 6 months after starting the treatment . for co2 laser treatment , continuous wave co2 laser , 10,600 nm , 3-mm spot size , fluence 5 j / cm , 13 passes , based on depth of the scar was performed . co2 laser treatment was performed only one time and the patients were followed at the start , 3 and 6 months after starting the treatment . in both the groups , any relevant side effect was recorded . digital photography was performed using sony 5 megapixel , dsc - f707 with the same light and angle . improvement in the depth of scar was graded by using a 6-point score as follows : ( 1 = non healing , 2 = 719% improvement , 3 = 2039% improvement , 4 = 4059% improvement , 5 = 6079% improvement , 6 = 80100% improvement ) . data analysis was performed using spss 13 software and statistical tests including t test , wilcoxon and mann - whitney test . overall , 92 patients , aged 1841 years , were evaluated . selected patients had skin type of ii - iv . forty - six patients were treated with 50% tca solution ( 39 females , 7 males ) and 46 patients were treated with co2 laser ( 35 males , 11 females ) . improvement of leishmaniasis scar at 6 months follow up was found to be 48.13 and 44.87% for 50% tca and co2 laser , respectively ( p = 0.55 ) . prevalence distribution of scar improvement based on a 6-point scale is shown in figure 1 . prevalence distribution of scar improvement in the two groups treated with co2 laser and 50% tca solution at 6-month follow up the reduction of scar depth before and after treatment was 1.630.74 ( p = 0.04 ) and 1.341.3 ( p = 0.04 ) ; both were significant as compared with the ones before treatment . however , there was no significant difference between the two methods of treatment regarding reduction of scar depth ( p = 0.813 ) . in the group treated with 50% tca solution , in 76.1% ( 35 patients ) of cases , no side effect was observed and in 23.9% ( 11 patients ) of cases , hyperpigmentation was observed in the scar site [ table 1 ] . prevalence distribution of age , sex and skin type in patients showing hyperpigmentation in the two treatment groups in the group treated with co2 laser , 76.1% ( 35 patients ) had no side effects and in 17.4% ( 8 patients ) hyperpigmentation and in 6.5% ( 3 patients ) resistant erythema was observed . one of the most important foci of cutaneous leishmaniasis is isfahan province , iran . in some villages of isfahan , therapeutic modalities for repairing these scars include peeling , laser , dermabrasion , punch excision , resurfacing and use of soft tissue fillers . application of tca with more than 40% concentration can induce medium depth peeling , and therefore , precipitation of epidermal proteins , coagulative necrosis of epidermal cells and collagen of papillary and upper reticular dermis . also , studies have shown that some clinical effects of tca are due to restoration of dermal structures and increase of collagen , glycosaminoglycans and elastin in the dermis . in another study , application of 50% tca solution in patients with acne scar showed that a patient 's satisfaction ranged from 33.3% after the first treatment session to 80% after the third session . the risk of post inflammatory hyperpigmentation is one of the limiting factors for use of tca solution in treatment of scars . however , the results of the study that was performed by al - waiz et al . showed that postinflammatory pigmentation was cleared in 73.4 after 3 months of treatment . focal tca peeling usually has a few side effects and the area usually heals very fast . co2 laser abrades epidermis and upper dermis without any damage to sebaceous glands , hair follicles and sweat duct , and therefore , causes remodeling of skin and neocollagenesis . our findings showed promising results regarding application of 50% tca solution for treatment of leishmaniasis scars . the results of treatment of leishmaniasis scars with 50% tca solution after 5 monthly applications . photograph b shows the results of treatment , 1 month after the fifth session of the treatment we suggest the use of focal tca peeling for treatment of cutaneous leishmaniasis scars .
background : the scars of the cutaneous leishmaniasis and psychological problems of this disease need different interventions for its correction.aim:our objective in this study was to compare the efficacy of 50% trichloroacetic acid ( tca ) solution and co2 laser for treatment of the atrophic scars due to leishmaniasis.materials and methods : this was a randomized clinical trial performed in 92 patients . 
 patients were randomized into two groups : the first group was treated with 50% tca solution , once monthly and for a maximum of 5 months , and the second group was treated with co2 laser which was performed for only one time . 
 patients were followed - up at 3 and 6 months after starting the treatment . 
 the improvement of scar was graded by a 6-point scale using digital camera and the collected data were analyzed using spss software.results:in this study , 74 females and 18 males were enrolled . 
 the improvement of scar was 48.13% in the tca group and 44.87% in the co2 laser group . 
 this difference was not statically significant ( p = 0.55 ) . 
 there was also no significant difference regarding side effects between these two groups.conclusion:the results of our study showed that efficacy of focal with 50% tca solution is compared with co2 laser in treatment of leishmaniasis scar . 
 because of the low cost and simple application of tca solution in comparison with co2 laser , we suggest use of this treatment for correction of leishmaniasis scar or the atrophic scars .