Clinical staging of melasma / 中华医学美学美容杂志

Objective To investigate the evaluation index of melasma staging by clinical manifestations and non-invasive skin detection technology.Methods A total of 195 patients with a clinical diagnosis of melasma were enrolled from the First Affiliated Hospital of Kunming Medical University.The skin with lesion enlarged,color darker,erythema,red occured after scratching or lesion faded after compressing with glass belonged to the active stage;on the contrary,it was in the stable stage.Reflectance confocal microscopy (RCM),dermoscopy,Mexameter 18 and LAB were used to observe skin lesions of different stage of melasma.Results There were 115 patients (59.0 ％) in the active stage of melasma and 80 patients (41.0 ％) in the stable stage.DMA score in active stage 35.08± 10.59 were significantly higher than that of the stable stage 15.06-4-9.20 (P＜0.05).There were statistically significant difference in the quantity of inflammatory cell and blood vessels between two stages of melasma (P＜0.05).Erythema index (EI) in active stage of melasma 376.35±61.39 were high-er than that of the stable stage 320.364± 62.40 (P＜0.05).A-value in active stage of melasma 13.28± 1.75 were higher than that of the stable stage 12.34± 1.78 (P＜0.05).However,there were no siginificant differences in the quantity of melenin,melanin index (MI),L-value and B-value.Conclusions Melasma could be divided into active stage or stable stage,respectively,according to its clinical manifestations.DMA score,quantity of inflammatory cells and blood vessels,EI and A-value could be used as the reference index of melasma staging.

Efficacy of Tranexamic Acid Containing Oral Medication on Melasma / 대한피부과학회지

BACKGROUND: Melasma causes considerable cosmetic disfigurement and none of the existing treatment modalities are satisfactory. Recently tranexamic acid has been reported to reduce hyperpigmentation in patients with melasma. OBJECTIVE: The purpose of the study was to evaluate the efficacy and safety of tranexamic acid containing oral medication for the treatment of melasma. METHODS: Forty-five female volunteers who had been diagnosed with melasma were enrolled in the present study. Patients were instructed to take medication for 8 weeks. The melanin index (MI) and erythema index (EI) were measured at baseline, and at 4 and 8 weeks. The melasma area and severity index (MASI) was scored at 0, 4, and 8 weeks. Self-satisfaction and safety evaluations were also performed at each visit. RESULTS: The mean MI measured on the lesional skin was decreased at 4 and 8 weeks compared with baseline (p80% of patients were satisfied with the medication. Adverse effects were minimal and two patients dropped out of the study due to drug-related urticaria and unexpected pregnancy. CONCLUSION: Tranexamic acid-containing oral medication is an effective and safe therapeutic modality for the treatment of melasma.

Changes of skin complexion after ultraviolet A (UVA) and ultraviolet B (UVB) exposure / 中华皮肤科杂志

Objective To observe the alteration of skin complexion after UVA and UVB exposure.Methods The back skin of ten females with skin type Ⅲ was subjected to single exposure to solar-simulated UVA of double minimal persistent pigment darkening (MPPD) or UVB of double minimal erythema dose (MED). Skin reflectance was assessed with clinical grading, spectcolometer and Mexameter MX 18 before irra-diation, 6 hours, 1, 7 and 14 days after the irradiation. Results After UVB irradiation, a~* value and erythema index (EI) abruptly increased at 6 hours and peaked on day 2; L~* value sharply declined on day 1; ITA° markedly decreased on day 7; melanin index (MI) declined within the first 2 days, but notably increased on day 7. After UVA irradiation, a~* and El value experienced no apparent changes; L~* value obviously declined at 6 hours; ITA° reached its lowest value on day 14; MI increased only on day 1. Conclusions There is a significant difference in the kinetics and extent of skin complexion changes after UVA and UVB irradiation. EI and a~* value are sensitive and accurate indices for evaluating sunburn, and MI and ITA ° for analyzing tanning.

Objective Assessment of Erythema caused by Metal Patch Testing using an Erythema Index Meter / Oral Science International

The patch test is the most reliable method for diagnosing a metal allergy. However, interpretation of patch test results depends on the experience of the investigator and on the conditions of the individual patient. In the case of patch tests for metal salts, irritant reactions such as pustular or follicular reactions are quite common. Therefore, one must be careful not to interpret irritant reactions as allergic responses, and objective standards to evaluate erythema in patch tests need to be established.In the present study, we attempted to objectively evaluate patch test results for metal salts using an erythema index meter. We used the Erythema Index Difference (EID) (patch test site erythema index (EI) minus the mean EI of healthy skin outside the patch test area and at the unit tape site) rather than the EI itself in order to eliminate the effects of the patch test unit and individual differences. We measured the EID over time in patients with suspected metal allergies to various metals. Significant differences in EID were observed among ++ assessments, + assessments and irritant reactions based on International Contact Dermatitis Research Group (ICDRG) standards. In considering changes in EID over time, allergic and irritant reactions can be discriminated with high sensitivity (73.3%) and specificity (91.2%).These results suggest that the measurement of erythema over time with an erythema index meter is useful for the objective assessment of metal patch test reactions.

The Skin Irritations of Corrosive and Non-corrosive Irritants in Patients with Sensitive Skin / 대한피부과학회지

BACKGROUND: Sensitive skin is largely agreed to be a lay term used by individuals who have reduced tolerance to frequent or prolonged use of cosmetics and toiletries, with symptoms ranging from subjective neurosensory forms of discomfort such as stinging, burning, itching, tightness and smarting sensations to visible signs of irritation such as erythema and scaling. Although the concept of sensitive skin is intriguing to many dermatologists, the diagnosis is dependant on self-perceived symptoms. Models to define sensitive skin are not standardized, and the term sensitive skin can be misleading. OBJECTIVE: The purpose of this study was to evaluate difference of influence to skin barrier function between corrosive and non-corrosive agents in sensitive skin. METHODS: 0.1%, 0.25%, 0.5%, 2% solution of sodium lauryl sulfate (SLS) and 1%, 2.5%, 5%, 20% solution of nonanoic acid (NAA) were applied on volar forearm skin for 24 hours in healthy controls and self-perceived sensitive skin subjects without underlying problems. Clinical score, transepidermal water loss (TEWL), and erythema-index (E-index) were compared between healthy controls and the sensitive skin group. RESULTS: Clinical scores, TEWL values and E-indices showed a rising curve concentration for each irritant in a similar pattern. There were no significant differences in clinical score and TEWL value between non-sensitive and sensitive skin. In contrast, E-indices evaluated from sensitive skin subjects were much higher than those in a healthy controls. CONCLUSION: An elevated TEWL value indicates barrier impairment. An increase in the erythema parameter shows that cutaneous vascular reactions have an unspecifically exaggerated reaction to various irritants and this induces multifarious inflammatory reactions and vasodilation. Therefore, the results of this study suggest that sensitive skin without underlying disease is derived from cutaneous vascular hyperreactivity and various inflammatory reactions, rather than barrier impairment.

Comparison of Skin Responses for Irritation Produced by Benzalkonium Chloride and Sodium Lauryl Sulfate / 대한피부과학회지

BACKGROUND: With the development of bioengineering techniques for noninvasive characterization of skin pathophysiology, the induction of irritant dermatitis by surfactants has been extensively studied. OBJECTIVE: We performed this study to compare the skin responses in terms of transepidermal water loss (TEWL) and erythema induced by benzalkonium chloride (BAC), a well-known non-corrosive irritant, in comparison with sodium lauryl sulfate (SLS), a representative corrosive irritant. METHOD: We applied 0.1, 0.2, 0.5, 1, and 2% solutions of BAC and SLS on volar forearm skin for 24 hours using a large Finn chamber with filter paper disc on 19 normal healthy subjects. TEWL and erythema index (E-index) were measured prior to testing, then at 30 minutes, one day, two days, three days, one week, and two weeks after the removal of the patches. RESULTS: TEWL values of BAC and SLS patch areas increased with concentration. However, BAC induced a significantly lower TEWL increase than SLS did at the corresponding concentrations. TEWL induced by BAC was highest at 30 minutes after the removal of the patch, whereas TEWL induced by SLS was highest at one day. TEWL values had recovered with the passage of time to baseline values at 2 weeks after removal of the patch at lower concentrations (0.1, 0.2, 0.5%) of SLS, but still showed significantly high TEWL values at 1% and 2% concentration SLS patch areas. TEWL values of BAC in 0.1, 0.2, 0.5 and 1% concentrations had recovered to the baseline values at 2 weeks after the removal of the patch, but not in 2% concentration BAC patch areas. E-indices of BAC and SLS increased with concentration in a similar reaction pattern. E-index induced by BAC was highest at 30 minutes after the removal of the patch, and E-index induced by SLS was highest at 30 minutes or 1 day after the removal of the patch. E-index of each concentration, except 2%, had recovered with the passage of time to baseline values on both BAC and SLS patch areas at 2 weeks, but E-indices of both 2% BAC and SLS did not recover at 2 weeks. CONCLUSION: Benzalkonium chloride showed much less damage to the skin barrier function compared to the corresponding concentration of SLS, whilst they showed a similar degree of erythema. Skin barrier function affected by the corrosive irritant SLS would need a more prolonged recovery time than skin barrier disruption by non-corrosive irritant BAC.

Effects of Skin Temperature on UV-induced Erythema and pigmentation in Human Skin in Vivo / 대한피부과학회지

BACKGROUND: Skin temperature at UV radiation exposure influences acute skin reaction such as erythema and pigmentation. As most biochemical systems are affected by temperature, thermal change preceding or following UV exposure could influence the responses in the way to cause vascular blood flow and change the inflammatory response OBJECTIVE: To investigate the influence of thermal change on UV-induced erythema and pigmentation by using objective and quantitative method METHODS: A sunlight fluorescent sunlamp (Waldmann UV 800) was used as a UV light source. Multiple sites of the lower back were irradiated with an increasing doses of UV, which were preceded or followed by heating or cooling. With a reflectance spectrophotometer, we assessed erythema and melanin indices at control, 0.1, 0.5, 1.0 and 2.0 MED dose-exposed sites. RESULTS: Compared with the only UV-exposed group, skin warming or cooling groups generally showed elevated acute erythema reaction with higher erythema indices. However, thermal changes preceding or following UV exposure had little effect on pigmentation except the post-warming group with UV exposure of 2 MED dose after 2 weeks. Our results indicate that altering the skin temperature modulates the degree of UV-induced erythema, but generally not skin pigmentation. CONCLUSION: The results in this study show that environmental factors such as heat or cooling have modulating effects on UV-induced skin reaction. These interactions should be considered when dealing with the effects of natural sun exposure or phototherapy.

Perturbation and Recovery of the Skin Barrier Function After Tape Stripping and Sodium Lauryl Sulfate Irritation / 대한피부과학회지

BACKGROUND: The main function of the stratum corneum is to serve as a barrier preventing the penetration of irritants and transepidermal water loss (TEWL). Previous studies have shown that the cutaneous barrier disruption by application of acetone or sodium lauryl sulfate (SLS) and tape stripping leads to various metabolic changes. Recent studies showed that there was some difference in the recovery rate between tape-stripped groups and acetone-treated groups, and an individual irritant not only exerted rather specific morphologic effects on the cellular components of the keratinocyte but also induced distinct morphological alterations of the different components of the stratum corneum. In other words, this data suggested that individual irritants could show different cutaneous barrier recoveries. OBJECTIVE: This study was done to compare the recovery rate after cutaneous barrier disruption between a tape-stripped group and a SLS irritated group, and to test the relationship among baseline TEWL, TEWL after the SLS irritation, recovery of TEWL, and number of strippings needed to increase TEWL up to 20g/m2/h. METHODS: The permeability barrier of normal human skin was disrupted by tape stripping and patch of SLS and the recovery rate was assessed by measure of TEWL and erythema (E-) index. RESULTS: The number of tape strippings needed to increase TEWL up to 20g/m2/h was 32.7+-9.6 (20-50). The recovery rate of TEWL was 56.85+-17.97% twenty-four hours after tape stripping and 51.55+/-24.73% after patch removal, and 82.70+/-8.70% and 76.61+/-11.14% four days after tape stripping and patch removal. There was no significant difference in the recovery rate of TEWL after the two methods of epidermal barrier perturbation. All the correlations among baseline TEWL, TEWL after the SLS irritation, recovery of TEWL, and number of strippings were not significant statistically. E-index after the tape stripping was 12.07+/-2.95 and higher than that after removal of SLS, 11.20+/-2.51. There was irregular recovery of E-index in the SLS irritated group, but not irregular in the tape-stripped group. There was no significant difference in the recovery rate between the two groups. CONCLUSION:There was no significant difference in the recovery rates of TEWL and E-index between the tape-stripped group and the SLS irritated group. We suggest that TEWL measurements may be more desirable than the measurement of E-index in the study of perturbation and recovery of the skin barrier function.

Cutaneous Irritation to Alpha Hydroxy Acids in Normal Human Skin / 대한피부과학회지

BACKGROUND: Alpha hydroxy acids (AHAs) are known to diminish corneocyte cohesion at the innermost levels of the stratum corneum and have been used in the treatment of various disorders of keratinization. However, their effect on skin barrier function and their irritant potential is not fully understood. OBJECTIVE: Our study was done to evaluate the skin irritancy of AHAs in normal human skin. METHODS: Patches with 1%, 5% and 10% solutions of lactic acid (LA) and glycolic acid (GA) were applied to the volar forearm of 20 healthy volunteers for 24 hours using large Finn chambers with filter paper. Visual scores, erythema (E-) index and transepidermal water loss (TEWL) were measured at 30 min, 24 h and 48 h after removal of the patches. RESULTS: The results are summarized as follows. 1. Visual scores were 0.1+/-0.3 (1%), 0.5+/-0.6 (5%) and 1.1+/-0.8 (10%) at 24 h after removal of LA, and were 0.2+/-0.4 (1%), 0.6+/-0.6 (5%) and 1.0+/-0.7 (10%) at 24 h after removal of GA. They were increased in proportion to the concentrations and there were significant differences in skin responses between the control and each concentration of the solutions. 2. E-indices were 9.1+/-2.1 (control), 8.8+/-1.8 (1%), 9.0+/-2.6 (5%) and 10.5+/-3.9 (10%) at 24 h after removal of LA, and were 9.4+/-1.8 (control), 9.3+/-2.3 (1%), 10.0+/-3.0 (5%) and 11.1+/-3.5 (10%) at 24 h after removal of GA. They were not increased in the patch areas of 1% and 5% solutions in both the LA and GA group, but were significantly increased in the patch areas of 10% solutions in both the LA and GA group. 3. TEWL values were 7.3+/-2.3 (control), 8.3+/-4.0 (1%), 9.8+/-4.5 (5%) and 16.7+/-9.1 (10%) at 24 h after removal of LA, and were 8.1+/-3.2 (control), 7.8+/-3.8 (1%), 8.6+/-3.0 (5%) and 10.9+/-4.1 (10%) at 24 h after removal of GA. They were not increased in the patch areas of 1% LA, 1% GA and 5% LA, but there were high significant differences between the controls and 10% solutions of both LA and GA. CONCLUSION: Visual scores were increased in all concentrations of AHAs tested, but the increase in E-index and TEWL values were not significant or minimal in 1% and 5% solutions of AHAs. These findings suggest that AHAs could be classified as non-corrosive irritants.

The Skin Responses to Dimethyl Sulfoxide in Normal Human Forearm Skin

BACKGROUND: Dimethyl sulfoxide (DMSO) is a strong urticariogenic agent and a primary irritant. A DMSO test which measures erythema and wheal responses in skin after exposure for 5 min could be a simple and easy method in evaluating cutaneous irritation. Several non-invasive bioengineering methods for the evaluation of skin irritancy have been developed in recent decades. OBJECTIVE: To evaluate whether the DMSO test using filter paper discs instead of the open well with measurements of transepidermal water loss (TEWL) and erythema index (E-index) could be useful to study skin irritancy. METHODS: Twenty healthy volunteers (19-29 years, 10 males and 10 females) with no history of atopic dermatitis were included. DMSO solutions (90%, 95%, and 100%) of 60l were applied to the left volar forearm for 5 min using filter paper discs (12mm) for large Finn chamber. Visual scores (whealing scores and erythema), TEWL and E-index were measured at 30 min after removal of the filter papers. RESULTS: The number of subjects showing erythema and wheals after DMSO exposure were: 6 (30%), 8 (40%) with 90% DMSO solution; 14 (70%), 15 (75%) with 95% DMSO solution; and 20 (100%), 20 (100%) with 100% DMSO solution, respectively. Whealing scores were 0.5±0.6 (90%), 1.4±1.1 (95%), 3.5±0.9 (100%), and erythema ones were 2.9±4.9 (90%), 7.7±7.2 (95%), 20.0±6.5 (100%). E-index results were 10.0±3.4 (90%), 10.9±3.1 (95%), 12.3±2.7 (100%), and TEWL values were 14.6±4.9 (90%), 21.0±8.8 (95%), 44.9±15.3 (100%). As the DMSO concentrations were increased, there were significant increases in whealing scores, and erythema and TEWL values. E-index results were not significant, but showed a rising score tendency. There were no significant differences between the males and the females. CONCLUSION: DMSO testing may be a quick and simple method to assess cutaneous irritation. Also, TEWL measurements may be more accurate and sensitive than those of E-index measurement in the assessment of erythema and wheals. DMSO testing using filter paper discs with TEWL measurement could be a useful method in the study of cutaneous irritation.

Cutaneous Irritation to Sodium Lauryl Sulfate and Sodium Lauroyl Glutamate / 대한피부과학회지

BACKGROUND: Sodium lauryl sulfate(SLS) is the most widely utilized model for studying acute and cumulative irritation. Sodium lauroyl glutamate(SLG) has exhibited a low irritation potential and an anti-irritating effect on other anionic surfactants. OBJECTIVE: Our study was done to compare the skin irritancy of SLS and SLG using non-in- vasive techniques. METHODS: Patches with 1% SLS and SLG solution were applied to the volar forearm of 20 healthy volunteers for 24 h. Finn chambers with 8mm(20pl) and 12mm(60pl) inner diameters were used. Visual scores, transepidermal water loss(TEWL) and an erythema(E)-index were measured at 30 min after removal of the patches, and every 24hours(h) up to 4 days. RESULTS: The results are summarized as follows. 1. Visual scores were 0.20+0.30(8mm) and 0.73+0.34(12mm) at 24 h after removal of 1% SLS and were 0.15+0.29(8mm) and 0.30+0.41(12mm) at 24 h after removal of 1% SLG. They were increased at 30 min and 24 h after removal and decreased towards normal at 4 days after removal. By chamber size, the skin response with large Firin chamber(12mm) increased more significantly than with the small Finn chamber(8mm). In the small Finn chamber, there were no significant differences in the skin response between 1% SLS and 1% SLG. In the large Finn chamber, the skin response with 1% SLS increased more significantly than with 1% SLG. 2. TEWL values were 11.14+4.77(8mm) and 20.48+10.61(12mm) at 24 h after removal of 1 % SLS and were 10.38+3.99 and 14.87+7.46 at 24 h after removal of 1% SLG. They were increased at 30 min after removal and decreased towards normal 4 days after removal. By chamber size, their results were the same as the visual scores. Also, on comparison between 1% SLS and 1% SLG, their results were the same as the visual scores. 3. E-index was 10.05+2.70(8mm) and 11.15+2.56(12mm) at 24 h after removal of 1% SLS and was 10.15+2.16 and 10.60+2.26 at 24 h after removal of 1% SLG. They were increased at 30 min after removal and decreased towards normal 4 days after removal. By chamber size, their results were the same as the visual scores. In the small and large Finn chamber, there were no significant differences in the skin response between 1% SLS and 1% SLG. CONCLUSION: SLS is more irritating than SLG. The large Finn chamber may be more suitable to yield positive irritant reactions than the small Finn chamber. Also, TEWL measurements may be a more accurate and sensitive method than the E-index.

Erythema and Melanin Index According to UVB Radiation Doses by Use of a Reflectance Spectrophotometer in Korean Young Adults / 대한피부과학회지

BACKGROUND: Methods of estimating the erythema and pigmentation reactions, such as MPE (Minimal Perceptible Erythema), ME(Minimal Erythema Dose) and MMD(Minimal Melanogenic Dose), are vulnerable to the variations of subjective visual measurements. OBJECTIVE: By using objective and quantitative methods, the erythema and pigmentaton responses were investigated. METHODS: A sunlight, fluorescent lamp(Waldmann UV 800) was used as a UVB light source. Multiple sites of the lower back were irradiated with an increasing dose by a constant amount, With a reflectance spectrophotometer (DermaSpectrometer(R)), erythema and melanin indices at control, MPE, MED, MMD sites were assessed. The dose-response angle of erythema and pigmentation were calculated. RESULTS: The erythema and pigmetation indices at the control, MPE, MED and MMD sites were 8.7+/-2.0AU/30.5+/-2.6AU, 10.5+/-2.7AU/32.6+/-3.6AU, 13.2+/-3.5AU/32.6+/-3.3AU, and 10.4+/-3.0AU/ 33.5+/-2.7AU, respectively. The calculated dose-response angle accurately measured the response of skin to UVB irradiation. CONCLUSION: In this study, use of a reflectance spectrophotometer appeared to be a more sensitive and effective method than visual assessment, in addition, dose-response angles may be an objective index for determination of skin responses to UVB irradiation.