Efficacy of isobutylamido thiazolyl resorcinol for prevention of laser-induced post-inflammatory hyperpigmentation: A randomized, controlled trial.

BACKGROUND: Q-switched (QS) Nd: YAG laser is one of the treatment options for solar lentigines (SLs). However, the incidence of post-inflammatory hyperpigmentation (PIH) is a common complication, especially in dark-complexioned skin. Isobutylamido thiazolyl resorcinol (ITR) has been reported as a preventive modality for ultraviolet B (UVB)-induced hyperpigmentation. AIMS: This study aims to evaluate the efficacy and safety of ITR for the prevention of laser-induced PIH. PATIENTS/METHODS: A randomized, evaluator-blinded study including 24 subjects with SLs was conducted. Three SLs of each patient were randomized into three groups, which were to apply ITR twice daily, once daily, and no application for 2 weeks. Thereafter, 532-nm QS Nd: YAG laser was performed. Incidence of laser-induced PIH, relative melanin index (RMI), mean luminance score (L*), hyperpigmentation score, and adverse events were recorded for 2 months post-laser. RESULTS: The incidence of PIH at the 4th week after laser treatment was significantly lower in the ITR twice-daily group compared to the no-application group (20.83% vs. 50%, p = 0.028). There was no statistically significant difference in RMI, mean L*, and hyperpigmentation score between treatments at all visits. No serious adverse events were reported regarding ITR application and laser treatment. CONCLUSION: Two-week application of ITR prior to QS: Nd YAG laser treatment may potentially reduce the incidence of PIH. A longer duration of application, including after the laser procedure, may be more beneficial for the prevention of laser-induced PIH.

Genotypic and Phenotypic Characteristics of Co-Trimoxazole-Induced Cutaneous Adverse Reactions.

BACKGROUND: Co-trimoxazole has been reported as a common culprit drug for various cutaneous adverse drug reactions (CADRs). However, information on genotypic and phenotypic characteristics is still limited. We aimed to study clinical characteristics, genetic suitability, laboratory findings, and treatment outcomes in patients with co-trimoxazole-induced CADR and determine variables associated with severe cutaneous adverse reactions (SCARs). METHODS: The medical records of all patients diagnosed with co-trimoxazole-induced CADR during October 2015 and October 2021 were reviewed. Clinical characteristics and laboratory investigation with an emphasis on human leukocyte antigen (HLA) class I and HLA-DRB1 results linked to subtypes of cutaneous adverse reactions were evaluated. RESULTS: Seventy-two patients diagnosed with co-trimoxazole-induced CADR were included in the study. Mean age at diagnosis was 38.0 ± 14.6 years old, and 72% were female. Subtypes of reactions included maculopapular eruption (MPE; 56.9%), drug reaction with eosinophilia and systemic symptoms (DRESS; 23.6%), Stevens-Johnson syndrome (SJS; 12.5%), fixed drug eruption (4.2%), and urticaria (2.8%). Characteristics that were significantly associated with SCARs included male gender (OR = 3.01, 95% CI: 1.04-8.75), HIV infection (OR = 3.48, 95% CI: 1.13-10.75), prophylactic use of co-trimoxazole (OR = 4.89, 95% CI: 1.54-15.57), and co-trimoxazole administration longer than 10 days (OR = 7.65, 95% CI: 2.57-22.78). HLA-B*38:02 was associated with co-trimoxazole-induced SJS, while HLA-A*11:01, HLA-B*13:01, and HLA-DRB1*12:01 were associated with co-trimoxazole-induced DRESS. HLA-B*52:01 was associated with co-trimoxazole-induced MPE. CONCLUSIONS: Co-trimoxazole could induce various phenotypes of CADRs. Genotypic and phenotypic factors that may potentially predict co-trimoxazole-induced SCARs include male gender, HIV infection, prophylactic and prolonged drug use, as well as the presence of HLA-A*11:01, HLA-B*13:01, HLA-B*38:02, or HLA-DRB1*12:01 alleles.

Intralesional Measles, Mumps, Rubella Vaccine versus Tuberculin Purified Protein Derivative Injections in the Treatment of Palmoplantar and Periungual Warts: A Double-Blind Randomized Controlled Trial.

BACKGROUND: Palmoplantar and periungual warts tend to be recalcitrant. Intralesional immunotherapy can provide high efficacy with additional benefit to distant warts. However, evidence on comparative effects between intralesional immunotherapy with measles, mumps, rubella vaccine (MMR) and tuberculin purified protein derivative (PPD) and roles of dermoscopy in predicting treatment outcomes in palmoplantar/periungual warts is limited. OBJECTIVES: The study aimed to compare efficacy and safety of intralesional MMR and PPD injections in treatment of palmoplantar/periungual warts and explore associations between dermoscopic findings and treatment outcomes. METHODS: We conducted a double-blind randomized controlled trial involving 40 patients with palmoplantar/periungual warts who were equally assigned to receive MMR or PPD. Intralesional injection was done every 2 weeks until clearance or maximum of 5 treatments. RESULTS: Complete resolution was higher in MMR than PPD group (90.0% vs. 80.0% in index lesion and 81.3% vs. 54.6% in distant lesions, respectively), although the differences were statistically nonsignificant. Dermoscopic findings were not significantly associated with complete resolution. Local swelling, i.e., the most common adverse event, occurred more frequently in PPD (40.0%) than MMR group (10.0%). CONCLUSION: This study suggests that intralesional immunotherapy with either MMR or PPD is efficacious in palmoplantar/periungual warts, with MMR showing a trend toward higher clearance and lower adverse events.

A comparative study of pain perception during the microfocused ultrasound procedure between topical anesthesia and combined topical anesthesia with forced air cooling.

BACKGROUND: The experience of pain during microfocused ultrasound with visualization (MFU-V) treatment is common and crucial for dictating patient satisfaction and retention. OBJECTIVE: To compare the pain perception during the MFU-V procedure between two pain reduction methods (topical anesthesia alone versus combined topical anesthesia with forced air cooling). MATERIALS AND METHODS: This was a prospective, single-blinded, randomized controlled trial. A square area on the inner side of both arms of healthy volunteers was marked as an experimental site and randomly assigned to receive each pain reduction method: topical anesthesia or combined topical anesthesia with forced air cooling. Thereafter, MFU-V was performed with a 4.5 MHz, 4.5 mm transducer (10 lines, 0.9 J) followed by a 7 MHz, 3.0 mm transducer (10 lines, 0.3 J). The visual analog scale (VAS) for pain was measured immediately after 4.5 mm transducer (T1a), immediately after 3.0 mm transducer (T1b), and after the entire procedure (T2). RESULTS: Twenty-one participants with a mean (SD) age of 34.67 (±6.18) years were enrolled. The mean (±SD) pain score of combined topical anesthesia with forced air cooling-treated area was 5.40 (±1.64), 4.80 (±1.63), and 5.40 (±1.56) at T1a, T1b, and T2, respectively. The mean pain score for topical anesthesia-treated areas was 5.89 (±1.45), 5.00 (±1.72), and 5.76 (±1.67) at T1a, T1b, and T2, respectively. There were no statistically significant differences in the pain perception between the two methods. CONCLUSION: The addition of forced air cooling is not beneficial for pain reduction during the MFU-V procedure because its temperature reduction effect cannot be delivered to the deep parts of the skin, which is the target site of MFU-V.

The role of topical capsaicin gel in pain management during microfocused ultrasound treatment for neck laxity.

BACKGROUND: The transient receptor potential vanilloid 1 (TRPV1) provides a heat and pain sensation (nociception). Capsaicin, a TRPV1 agonist, has been shown to induce a refractory period in the nerve terminal expressing TRPV1 and create long-term nerve terminal defunctionalization. OBJECTIVE: To evaluate the efficacy of capsaicin for pain reduction during microfocused ultrasound with visualization (MFU-V) treatment. METHODS AND MATERIALS: A randomized, split-side study including 24 subjects was conducted. A combined 0.025% capsaicin gel and topical anesthetic were randomly applied on one side of the neck, and a topical anesthetic monotherapy was applied on the contralateral side for 30 min before MFU-V treatment. Pain score (visual analog scale, 0-10) was evaluated at T1 (before MFU-V), T2a (after the 4.5-mm transducer treatment), T2b (after the 3.0-mm transducer treatment), and T3 (after the entire treatment). Side effects were recorded. RESULTS: Mean pain scores at T2a for combined and single regimens were 5.19 (±2.26) and 6.91 (±1.72), respectively (p < 0.001). The capsaicin-treated side had a lower pain score at T2b and T3 (p < 0.001). Redness was longer on the capsaicin-treated side (112.67 vs. 10.68 min, p < 0.001). No other adverse events including contact dermatitis were reported. CONCLUSION: A single application of a combined 0.025% capsaicin gel with topical anesthesia produces a significantly lesser pain score during the MFU-V treatment. Defunctionalization of TRPV1 may explain the alleviation of painful sensations caused by heat from MFU-V.

Incobotulinum Toxin Type A for Treatment of Ultraviolet-B-Induced Hyperpigmentation: A Prospective, Randomized, Controlled Trial.

Incobotulinum toxin A (IncoBoNT-A) is effective in preventing ultraviolet B (UVB)-induced hyperpigmentation. This prospective, randomized, controlled study aimed to evaluate the effect of IncoBoNT-A on the treatment of UVB-induced hyperpigmentation in 15 volunteers. Five hyperpigmentation squares (2 × 2 cm) were induced by local UVB on the abdomen at baseline. At Day 7, each site was randomized to receive no treatment (control), normal saline, or intradermal IncoBoNT-A injection with 1:2.5, 1:5, and 1:7.5 dilutions (12, 6, and 4 units, respectively). The mean lightness index (L*), hyperpigmentation improvement score evaluated by blinded dermatologists, and participant satisfaction scores were obtained at Days 21, 28, and 35. At Day 21, improvements in mean L* of 1:2.5, 1:5, and 1:7.5 IncoBoNT-A-treated, saline-treated, and control sites were 14.30%, 12.28%, 6.62%, 0.32%, and 4.98%, respectively (p = 0.86). At Day 28, the improvement in mean L* in IncoBoNT-A-treated groups was superior to that in the other groups. In terms of the hyperpigmentation improvement score, 12 participants (80%) experienced better outcomes with the IncoBoNT-A-injected site compared with the other sites. IncoBoNT-A, especially at higher concentrations, showed some positive effects on the treatment of UVB-induced hyperpigmentation. This may serve as an adjuvant treatment for hyperpigmentary conditions that are aggravated by UVB.

Study of botulinum toxin type A for the treatment of ultraviolet B-induced hyperpigmentation: A prospective, randomized, controlled trial.

BACKGROUND: Botulinum toxin type A (BTX-A) has been used experimentally under various dermatological conditions. Recent studies have revealed a preventive effect of BTX-A against ultraviolet B (UVB)-induced skin hyperpigmentation. OBJECTIVE: We examined the effect of BTX-A for the treatment of UVB-induced hyperpigmentation in humans. MATERIAL AND METHODS: A prospective, double-blind, randomized controlled trial was conducted. UVB irradiation induced five separate hyperpigmented squares on the abdomen. Seven days after irradiation, all squares were randomly assigned to five intervention groups: control, 0.9% normal saline injection, 12 units (1:2.5), 6 units (1:5), and 4 units (1:7.5) of onabotulinum toxin injections. The lightness index (L*), hyperpigmentation improvement score rated by a blinded physician, and participant satisfaction scores were obtained at 14, 21, and 28 days after injection. RESULTS: Fifteen participants (mean age 36.9 years, Fitzpatrick skin types III-IV) completed the study. The BTX-A (1:2.5)-treated site had a lower degree of hyperpigmentation at all time points, as measured by mean L* and hyperpigmentation improvement scores. However, there were no statistically significant differences between the groups. Participants were most satisfied with the control site. CONCLUSION: Intradermal BTX-A injection had no therapeutic effect on UVB-induced hyperpigmentation. However, the role of BTX-A injections in the treatment of other hyperpigmentary conditions requires further elucidation.

Randomized, evaluator-blinded comparative study of a potassium titanyl phosphate (KTP) 532-nm picosecond laser and an alexandrite 755-nm picosecond laser for the treatment of solar lentigines in Asians.

BACKGROUND: Various pigment-specific lasers can be used to treat solar lentigines. However, the most effective treatment options remain to be explored to reduce complications, such as postinflammatory hyperpigmentation, especially in dark-skinned patients. OBJECTIVES: This study aims to compare the efficacy and safety between the KTP 532-nm picosecond laser and the alexandrite 755-nm picosecond laser for the treatment of solar lentigines in Asians. MATERIALS AND METHODS: Thirty patients who had at least two solar lentigines on their arms were enrolled. A total of 30 paired lentiginous lesions were randomly selected for a single treatment with either a KTP 532-nm picosecond laser or an alexandrite 755-nm picosecond laser. Mean luminance score (L*) was evaluated at baseline and at 6 and 12 weeks to determine treatment efficacy. Improvement was assessed by a blinded physician using a 5-point score. Satisfaction was rated by patients using a visual analog scale. All adverse events were documented. RESULTS: All 30 patients completed the study. Both lasers showed significant improvement in mean L* from baseline (p < 0.001). With the parameter settings employed, lesions treated with the alexandrite 755-nm picosecond laser showed greater improvement in mean L* when compared with treatment with the KTP 532-nm picosecond laser at 12 weeks follow-up (p = 0.002). According to physician scoring, more than 50% improvement was observed in 25 and 19 lesions of the alexandrite 755-nm picosecond laser group and the KTP 532-nm picosecond laser group, respectively. Adverse events did not differ between groups. A significantly higher satisfaction score was observed with the alexandrite 755-nm picosecond laser at the last visit (p = 0.038). CONCLUSION: Both types of picosecond laser may be used to treat solar lentigines. Proper treatment settings and endpoint observation are the most important factor to achieve a successful outcome.

A single-blinded, randomized, controlled trial comparing efficacy between low-fluence alexandrite 755-nm picosecond laser and low-fluence neodymium-doped yttrium aluminum garnet (Nd:YAG) 1064-nm picosecond laser for the treatment of ultraviolet B-induced hyperpigmentation.

BACKGROUND: Hyperpigmentation is a common concern of patients in dermatology clinics. Although there are many treatment options, lasers are considered a promising therapy for various hyperpigmentary conditions. OBJECTIVES: This study aims to evaluate the efficacy of alexandrite 755-nm picosecond and neodymium-doped yttrium aluminum garnet (Nd:YAG) 1064-nm picosecond lasers for the treatment of ultraviolet B (UVB)-induced hyperpigmentation in Asians. MATERIALS AND METHODS: A randomized, single-blinded study was conducted. UVB-induced hyperpigmentation was performed in three spots by narrowband UVB. After 2 weeks, these three spots were allocated into 755-treated, 1064-treated, and control sites. Patients received weekly laser treatments for five sessions. Follow-ups were scheduled at 1 and 2 months after the last session. RESULTS: Twenty patients attended the study. Overall, 755-nm and 1064-nm picosecond lasers showed a significant improvement in the mean lightness index (L*) compared to the control site, which started at Day 49 and Day 77, respectively. The mean L* of the 755-nm-treated site was also higher than that of the 1064-nm-treated site at Day 105 (p ≤ 0.001). Initially, the mean L*, physician's visual analog scale (VAS), and patient satisfaction with the 1064-nm picosecond laser were better than those with the 755-nm picosecond laser. Nevertheless, an inversion of the mean L* and VAS was noted at Day 49, whereas the mean patient satisfaction was noted at Day 77. In the subgroup analysis, a 755-nm picosecond laser effectively treated Fitzpatrick skin types (FPTs) III and IV. However, the mean L* of the 1064-nm picosecond laser was not significantly different from that of the control for FPT4. CONCLUSION: The alexandrite 755-nm picosecond and Nd:YAG 1064-nm picosecond lasers appear to be effective and safe modalities for treating UVB-induced hyperpigmentation. With the setting employed in this study, the outcome after the 755-nm picosecond laser treatment seemed superior to that of the 1064-nm picosecond laser treatment, especially for FPT4.

A study of combined microfocused ultrasound and hyaluronic acid dermal filler in the treatment of enlarged facial pores in Asians.

BACKGROUND: Enlarged facial pores are a common cosmetic complaint in practice. Microfocused ultrasound with visualization (MFU-V) and low-degree crosslinked hyaluronic acid filler (L-HA) injection has recently become a popular procedure for skin rejuvenation. The effectiveness of the combined MFU-V and L-HA injection in the treatment of enlarged pores has not been evaluated. OBJECTIVES: To compare the efficacy of MFU-V monotherapy (single technique) and MFU-V combined with L-HA injection (combined technique) for the treatment of enlarged facial pores in Asians. METHODS: We conducted a randomized, single-blinded, split-face study on participants with enlarged facial pores. Each side of the face was randomly assigned to treatment with one session of single technique or combined technique. Pore volume was objectively measured by an Antera 3D® system. Subjective assessment was evaluated by one-blinded physician using a pore grading score (0-4). Patients rated the improvement in terms of satisfaction using the visual analog scale (VAS, 0-10). RESULTS: Forty-six participants completed the study. The mean pore volume of both sides declined with statistical significance at every visit compared to baseline, with the lowest mean at 4 months post-treatment. The combined technique showed a lower mean pore volume than single technique throughout the follow-ups. Physician's subjective evaluation showed no statistically significant difference between the two techniques. The patient satisfaction score showed a similar trend to the mean pore volume, with a statistically significant difference at 4 and 6 months post-treatment. CONCLUSIONS: Both techniques are effectively minimize enlarged facial pores. The combined technique resulted in more patient satisfaction.

Application of Topical Immunotherapy in the Treatment of Alopecia Areata: A Review and Update.

Treatment of extensive or recalcitrant alopecia areata (AA) is a major clinical challenge. Even after thorough investigation of several medications, its treatment outcomes have remained unsatisfactory. While there is no US Food and Drug Administration-approved medication for AA yet, topical immunotherapy has been a well-documented treatment option. Dinitrochlorobenzene, squaric acid dibutylester, and diphenylcyclopropenone are three substances that have demonstrated efficacy in the treatment of extensive or recalcitrant AA. Despite being commonly used, the mechanism underlying topical immunotherapy is not well-elucidated and a wide range of clinical efficacies have been reported in the literature. The aim of this review was to summarize and update the pharmacology, mechanism of action, therapeutic efficacy, and tolerability of topical immunotherapy in the treatment of AA.

Rituximab Therapy for Treatment of Pemphigus in Southeast Asians.

BACKGROUND: Rituximab provides more effective and less adverse effects than the standard dose of corticosteroids, but evidence on its efficacy and safety in the Thai population is lacking. OBJECTIVE: To evaluate the efficacy and safety of rituximab in the treatment of pemphigus and also to determine prognostic factors linked to the treatment outcomes. METHODS: Pemphigus patients who received rituximab from November 2017 to December 2020 were retrospectively reviewed. The outcome was evaluated by using early (end of consolidation phase [ECP]) and late endpoints (complete remission [CR] on/off therapy, immunological remission [IR], and relapse). Adverse events were noted. Prognostic factors associated with remission and relapse were analyzed. RESULTS: Of 53 pemphigus patients, all attained ECP within 1.61 months. Almost 80% achieved CR on therapy within a median time of 6.36 months, while 33.9% reached CR off therapy in 19.74 months. Nearly half had IR within a median time of 6.88 months. Relapse occurred in 33.3% with a median time of 14 months. In multivariate analysis, receiving rituximab within 12 months of disease duration was more likely to achieve CR off therapy and IR (hazard ratio [HR] 3.79; 95% confidence interval [CI] 1.38, 10.42; P = 0.01 and HR 2.74; 95% CI 1.12, 6.69; P = 0.027, respectively), whereas older patients and positive anti-desmoglein 1 levels at the time of CR were predictive indicators for relapse (HR 1.07; 95% CI 1.01, 1.13; P = 0.036 and HR 4.38; 95% CI 1.24, 15.46; P = 0.022, respectively). The treatment-related adverse effects occurred in 33.9%. CONCLUSION: Rituximab is effective and safe in Thai pemphigus patients. Early administration of rituximab was a predictor of clinical and immunological remission. Older age and persistently positive anti-Dsg1 were correlated with disease relapse.