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G J Groeneveld - One of the best experts on this subject based on the ideXlab platform.
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the ultraviolet b inflammation model Postinflammatory Hyperpigmentation and validation of a reduced uvb exposure paradigm for inducing hyperalgesia in healthy subjects
European Journal of Pain, 2019Co-Authors: Pieter S Siebenga, Guido Van Amerongen, Erica S Klaassen, Marieke L De Kam, Robert Rissmann, G J GroeneveldAbstract:BACKGROUND Pain models are commonly used in drug development to demonstrate analgesic activity in healthy subjects and should therefore not cause long-term adverse effects. The ultraviolet B (UVB) model is a model for inflammatory pain in which three times the minimal erythema dose (3MED) is typically applied to induce sensitization. Based on reports of long-lasting Postinflammatory Hyperpigmentation (PIH) associated with 3MED, it was decided to investigate the prevalence of PIH among subjects who were previously exposed to 3MED at our research centre. In addition, re-evaluation of the UVB inflammation model using a reduced exposure paradigm (2MED) was performed in healthy subjects. METHODS In the first study, all 142 subjects previously exposed to 3MED UVB were invited for a clinical evaluation of PIH. In the second study, 18 healthy subjects were exposed to 2MED UVB, and heat pain detection threshold (PDT) and PIH were evaluated. RESULTS In total, 78 of the 142 subjects responded. The prevalence of PIH among responders was 53.8%. In the second study, we found a significant and stable difference in PDT between UVB-exposed and control skin 3 hr after irradiation; 13 hr post-irradiation, the least squares mean estimate of the difference in PDT ranged from -2.6°C to -4.5°C (p < 0.0001). Finally, the prevalence of PIH was lower in the 2MED group compared to the 3MED group. CONCLUSIONS The 3MED model is associated with a relatively high prevalence of long-lasting PIH. In contrast, 2MED exposure produces stable hyperalgesia and has a lower risk of PIH and is therefore recommended for modelling inflammatory pain. SIGNIFICANCE Postinflammatory Hyperpigmentation is an unwanted long-term side effect associated with the UVB inflammation model using the 3× minimal erythema dose (3MED) paradigm. In contrast, using a 2MED paradigm results in hyperalgesia that is stable for 36 hr and has a lower risk of inducing Postinflammatory Hyperpigmentation.
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The ultraviolet B inflammation model: Postinflammatory Hyperpigmentation and validation of a reduced UVB exposure paradigm for inducing hyperalgesia in healthy subjects.
European Journal of Pain, 2019Co-Authors: Pieter S Siebenga, Guido Van Amerongen, Erica S Klaassen, Marieke L De Kam, Robert Rissmann, G J GroeneveldAbstract:BACKGROUND Pain models are commonly used in drug development to demonstrate analgesic activity in healthy subjects and should therefore not cause long-term adverse effects. The ultraviolet B (UVB) model is a model for inflammatory pain in which three times the minimal erythema dose (3MED) is typically applied to induce sensitization. Based on reports of long-lasting Postinflammatory Hyperpigmentation (PIH) associated with 3MED, it was decided to investigate the prevalence of PIH among subjects who were previously exposed to 3MED at our research centre. In addition, re-evaluation of the UVB inflammation model using a reduced exposure paradigm (2MED) was performed in healthy subjects. METHODS In the first study, all 142 subjects previously exposed to 3MED UVB were invited for a clinical evaluation of PIH. In the second study, 18 healthy subjects were exposed to 2MED UVB, and heat pain detection threshold (PDT) and PIH were evaluated. RESULTS In total, 78 of the 142 subjects responded. The prevalence of PIH among responders was 53.8%. In the second study, we found a significant and stable difference in PDT between UVB-exposed and control skin 3 hr after irradiation; 13 hr post-irradiation, the least squares mean estimate of the difference in PDT ranged from -2.6°C to -4.5°C (p
Iltefat H Hamzavi - One of the best experts on this subject based on the ideXlab platform.
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Trichloroacetic acid model to accurately capture the efficacy of treatments for Postinflammatory Hyperpigmentation
Archives of Dermatological Research, 2020Co-Authors: Alexis B. Lyons, Tasneem F. Mohammad, Taylor L. Braunberger, Indermeet Kohli, Amanda F. Nahhas, Cynthia L. Nicholson, Nathan T. Nartker, Krishna Modi, Mary S. Matsui, Iltefat H HamzaviAbstract:Postinflammatory Hyperpigmentation (PIH) occurs following cutaneous injury and is common following resolution of acne especially in patients with skin of color. The objective of this study was to further validate a trichloroacetic acid (TCA)-induced PIH model and compare it to acne-induced PIH using topical bakuchiol, a botanical extract that has been shown to have antimicrobial, anti-inflammatory, antioxidant, and antiacne properties. A prospective, non-randomized clinical trial was conducted on subjects with skin phototypes IV–VI with a history of acne-induced PIH. Subjects applied bakuchiol or vehicle cream twice daily to 2 acne-induced and 2 TCA-induced PIH lesions for 28 days with a third lesion serving as a control in each group. Degree of improvement was defined as the change in the Investigator Global Assessment (IGA) score over 28 days of treatment. Twenty subjects (6 males, 14 females) completed the study. For TCA-induced PIH sites, there was a statistically significant ( p 0.05). TCA-induced PIH sites were uniform in size and pigment intensity thereby allowing better comparison among sites. This emphasizes the relevance of using this model for PIH which may help reduce the barriers in clinical trials and help improve access to treatments for patients who suffer from PIH. The results suggest that topical bakuchiol may decrease the severity of PIH.
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The Role of Sunscreen in Melasma and Postinflammatory Hyperpigmentation.
Indian Journal of Dermatology, 2020Co-Authors: Sakeena Fatima, Tasneem F. Mohammad, Taylor L. Braunberger, Iltefat H HamzaviAbstract:Photosensitive conditions such as melasma and Postinflammatory Hyperpigmentation (PIH) are exacerbated by exposure to ultraviolet (UV) rays and visible light making sunscreen use an essential component of treatment. This is especially true in skin of color patients who are less likely to use photoprotection, even if diagnosed with these photoexacerbated conditions. We aimed to evaluate the body of literature to provide evidence for the use of sunscreen in the treatment of melasma and PIH. We reviewed English articles from PubMed, Journals@Ovid Full Text, and Embase using the search terms “sunscreen” and either “melasma” “PIH,” or “post-inflammatory Hyperpigmentation.” Nine relevant publications provide evidence that a broad spectrum of protection, including UVA, UVB, and visible light within sunscreens can play an adjuvant role in therapy for melasma and PIH by stabilizing and improving these pigmentary disorders in skin of color patients. This review illustrates the advantages and limitations of sunscreen use, as well as practice gaps in photoprotection in the skin of color patients with melasma and PIH.
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Laser Treatments for Postinflammatory Hyperpigmentation: A Systematic Review.
JAMA Dermatology, 2017Co-Authors: Oma Agbai, Iltefat H Hamzavi, Jared JagdeoAbstract:Importance Lasers are gaining interest as a treatment option for Postinflammatory Hyperpigmentation (PIH) but can pose a clinical dilemma given the risk for laser-induced or exacerbated PIH. Objective To assess the clinical evidence for the use of lasers in the treatment of PIH. Evidence Review A systematic review was performed by searching PubMed databases from January 1, 1990, through May 31, 2016. Included studies involved laser treatment for PIH with the degree of pigmentation as a measure of outcome. The search was filtered to include only clinical studies written in the English language. Study methods were analyzed and the reproducibility of the studies was graded. Outcome measures varied from study to study and included concentration of melanin and hemoglobin, patient satisfaction questionnaires, clinical photography, subjective clinical improvement, light microscopy, melanin index, reflectance spectroscopy, and/or skin biopsy evaluated by a blinded dermatopathologist. Findings Of 1295 results, 20 unique studies with 224 patients met the inclusion criteria. These studies included 1 randomized clinical observer-blinded study (6 patients), 4 nonrandomized clinical trials (133 patients), 1 cohort study (34 patients), 7 case series (44 patients), and 7 case reports (7 patients). Multiple lasers were studied; however, most of the studies were not methodologically rigorous. Some studies showed no improvement or worsening of PIH after laser treatment. The most extensively studied device was the Q-switched Nd:YAG laser, which has shown promising results based on multiple outcome measures as listed above. Conclusions and Relevance Some lasers may be beneficial in the treatment of PIH. The evidence suggests that additional studies would be required to determine the benefit of laser treatment of PIH.
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Postinflammatory Hyperpigmentation: A comprehensive overview: Treatment options and prevention.
Journal of the American Academy of Dermatology, 2017Co-Authors: Suteeraporn Chaowattanapanit, Narumol Silpa-archa, Indermeet Kohli, Henry W. Lim, Iltefat H HamzaviAbstract:Postinflammatory Hyperpigmentation (PIH) occurs after various dermatoses, exogenous stimuli, and dermatologic procedures. The clinical course of PIH is chronic and unpredictable, although the probability of resolution of epidermal Hyperpigmentation is better than those of dermal Hyperpigmentation. PIH can be prevented or alleviated. When it does occur, the underlying inflammatory conditions should be sought and treated as the first step to reduce the progression of inflammation and PIH (which is an inflammatory consequence). If the inflammatory conditions subsides or there is no evidence of inflammation at the time of diagnosis, the treatments of PIH should be considered as the next step. Understanding the available treatment options helps the physician choose the appropriate treatment for each patient. Having a reproducible model for PIH is essential for the development of treatment modalities. The second article in this 2-part continuing medical education series on PIH specifically addresses the evidence that supports medical and procedural treatments of PIH and other forms of acquired Hyperpigmentation. It also describes a PIH model and provides an algorithm for clinical practice along with discussion about the prevention of PIH.
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Postinflammatory Hyperpigmentation: A comprehensive overview: Epidemiology, pathogenesis, clinical presentation, and noninvasive assessment technique.
Journal of the American Academy of Dermatology, 2017Co-Authors: Narumol Silpa-archa, Suteeraporn Chaowattanapanit, Indermeet Kohli, Henry W. Lim, Iltefat H HamzaviAbstract:Postinflammatory Hyperpigmentation (PIH) commonly occurs after various endogenous and exogenous stimuli, especially in dark-skinned individuals. PIH is one of the most common complications of procedures performed using laser and other light sources. The severity of PIH is determined by the inherent skin color, degree and depth of inflammation, degree of dermoepidermal junction disruption, inflammatory conditions, and the stability of melanocytes, leading to epidermal and dermal melanin pigment deposition. The depth of melanin pigment is the key factor to predict prognosis and treatment outcome. Epidermal Hyperpigmentation fades more rapidly than dermal Hyperpigmentation. Various inflammatory disorders can eventually result in PIH. The evaluation of pigmentation using noninvasive tools helps define the level of pigmentation in the skin, pigmentation intensity, and guides therapeutic approaches. This first article in this 2-part series discusses the epidemiology, pathogenesis, etiology, clinical presentation, differential diagnoses, and investigation using noninvasive assessment techniques that objectively determine the details of pigmentation.
Valerie D. Callender - One of the best experts on this subject based on the ideXlab platform.
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Therapeutic Insights in Melasma and Hyperpigmentation Management
Journal of drugs in dermatology : JDD, 2019Co-Authors: Kimberly A. Huerth, Shahzeb Hassan, Valerie D. CallenderAbstract:Melasma and Postinflammatory Hyperpigmentation (PIH) are the most common forms of dyschromia in patients with skin of color. Both are associated with a high psychological burden of disease. To exacerbate this burden, the need for treatment is chronic, and the results are often suboptimal in the eyes of the patient. Successful treatment is therefore contingent upon a correct diagnosis, patient education, and a carefully considered therapeutic approach. The latter is often multimodal in its design, incorporating sun protection, topical and systemic medications, and in some cases, procedural intervention. Although topical hydroquinone is a mainstay of treatment for melasma and PIH, there are alternatives that have emerged as of late that have shown varying degrees of promise, both in terms of safety and efficacy. In this article, we review the epidemiological, clinical, and histologic features of melasma and Postinflammatory Hyperpigmentation, and discuss important considerations for both established and emerging treatments for these vexingly common and difficult to treat conditions.
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Polypodium leucotomos as an Adjunct Treatment of Pigmentary Disorders.
The Journal of clinical and aesthetic dermatology, 2014Co-Authors: Mark S. Nestor, Valerie D. Callender, Vivian W Bucay, Joel L. Cohen, Neil S. Sadick, Heidi A. WaldorfAbstract:Introduction: Extracts of the tropical fern Polypodium leucotomos appear to possess beneficial properties for the skin attributed to the presence of numerous compounds within the extract that have antioxidant and photoprotective properties. Orally administered Polypodium leucotomos may provide protection against the detrimental photoaging effects of sunlight and can also help reduce the frequency and severity of polymorphous light eruption. Polypodium leucotomos has also been shown to be beneficial for the prevention and potential treatment of several aesthetically relevant conditions. Objective: The purpose of this review is to investigate the beneficial role of Polypodium leucotomos as an adjunct treatment for vitiligo, melasma, and Postinflammatory Hyperpigmentation. Results: Based on a review of relevant literature including the results of a randomized, placebo-controlled study, the oral administration of Polypodium leucotomos significantly improved the severity of melasma in women after 12 weeks. Three randomized, double-blind, placebo-controlled studies have demonstrated significant improvements in vitiligo when oral Polypodium leucotomos therapy was combined with psoralens plus ultraviolet A and narrowband ultraviolet B. No controlled studies have assessed the efficacy of Polypodium leucotomos for the treatment of Postinflammatory Hyperpigmentation; however, its known antioxidant and anti-inflammatory properties and demonstrated effectiveness for melasma support its use for treating this condition. No adverse events have been associated with the use of Polypodium leucotomos. Conclusion: In addition to preventing many harmful effects associated with sunlight exposure, orally administered Polypodium leucotomos also appears to provide adjunctive benefits in treating vitiligo, melasma, and may have the potential to help with Postinflammatory Hyperpigmentation.
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Postinflammatory Hyperpigmentation
American Journal of Clinical Dermatology, 2011Co-Authors: Valerie D. Callender, Erica C. Davis, Sharleen St. Surin-lord, Marissa MaclinAbstract:Postinflammatory Hyperpigmentation (PIH) is a reactive hypermelanosis and sequela of a variety of inflammatory skin conditions. PIH can have a negative impact on a patient’s quality of life, particularly for darker-skinned patients. Studies show that dyschromias, including PIH, are one of the most common presenting complaints of darker-skinned racial ethnic groups when visiting a dermatologist. This is likely due to an increased production or deposition of melanin into the epidermis or dermis by labile melanocytes. A variety of endogenous or exogenous inflammatory conditions can culminate in PIH and typically most epidermal lesions will appear tan, brown, or dark brown while dermal hypermelanosis has a blue-gray discoloration. Depigmenting agents target different steps in the production of melanin, most commonly inhibiting tyrosinase. These agents include hydroquinone, azelaic acid, kojic acid, arbutin, and certain licorice (glycyrrhiza) extracts. Other agents include retinoids, mequinol, ascorbic acid (vitamin C), niacinamide, N -acetyl glucosamine, and soy, and these products depigment by different mechanisms. Certain procedures can also be effective in the treatment of PIH including chemical peeling and laser therapy. It is important to note that these same therapeutic modalities may also play a role in causing PIH. Lastly, those lesions that are not amenable to medical or surgical therapy may experience some improvement with cosmetic camouflage.
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Postinflammatory Hyperpigmentation: A Review of the Epidemiology, Clinical Features, and Treatment Options in Skin of Color
The Journal of clinical and aesthetic dermatology, 2010Co-Authors: Erica C. Davis, Valerie D. CallenderAbstract:Postinflammatory Hyperpigmentation is a common sequelae of inflammatory dermatoses that tends to affect darker skinned patients with greater frequency and severity. Epidemiological studies show that dyschromias, including Postinflammatory Hyperpigmentation, are among the most common reasons darker racial/ethnic groups seek the care of a dermatologist. The treatment of Postinflammatory Hyperpigmentation should be started early to help hasten its resolution and begins with management of the initial inflammatory condition. First-line therapy typically consists of topical depigmenting agents in addition to photoprotection including a sunscreen. Topical tyrosinase inhibitors, such as hydroquinone, azelaic acid, kojic acid, arbutin, and certain licorice extracts, can effectively lighten areas of hypermelanosis. Other depigmenting agents include retinoids, mequinol, ascorbic acid, niacinamide, N-acetyl glucosamine, and soy with a number of emerging therapies on the horizon. Topical therapy is typically effective for epidermal Postinflammatory Hyperpigmentation; however, certain procedures, such as chemical peeling and laser therapy, may help treat recalcitrant Hyperpigmentation. It is also important to use caution with all of the above treatments to prevent irritation and worsening of Postinflammatory Hyperpigmentation.
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Postinflammatory Hyperpigmentation: evolving combination treatment strategies.
Cutis, 2006Co-Authors: Susan C. Taylor, Cm, Roberts We, Marta I Rendon, Valerie D. Callender, Fu J, Shalita ArAbstract:Abstract Postinflammatory Hyperpigmentation (PIH) is a common acquired excess of pigment in the epidermal and/or dermal layers of the skin. Lesions persist for extended periods if untreated, thus therapy is warranted. Topical monotherapies include the standard bleaching agent hydroquinone (HQ) as well as retinoids. Recently, several fixed-dose combination products were introduced to the armamentarium: HQ 4%-retinol 0.15% in a microsponge formulation; HQ 4%-retinol 0.3%; mequinol 2%-tretinoin (RA) 0.01%; and fluocinolone acetonide (FA) 0.01%, HQ 4%, and RA 0.05%. Recent findings have suggested that mequinol 2%-RA 0.01% solution is a promising alternative for the treatment of PIH.
Pieter S Siebenga - One of the best experts on this subject based on the ideXlab platform.
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the ultraviolet b inflammation model Postinflammatory Hyperpigmentation and validation of a reduced uvb exposure paradigm for inducing hyperalgesia in healthy subjects
European Journal of Pain, 2019Co-Authors: Pieter S Siebenga, Guido Van Amerongen, Erica S Klaassen, Marieke L De Kam, Robert Rissmann, G J GroeneveldAbstract:BACKGROUND Pain models are commonly used in drug development to demonstrate analgesic activity in healthy subjects and should therefore not cause long-term adverse effects. The ultraviolet B (UVB) model is a model for inflammatory pain in which three times the minimal erythema dose (3MED) is typically applied to induce sensitization. Based on reports of long-lasting Postinflammatory Hyperpigmentation (PIH) associated with 3MED, it was decided to investigate the prevalence of PIH among subjects who were previously exposed to 3MED at our research centre. In addition, re-evaluation of the UVB inflammation model using a reduced exposure paradigm (2MED) was performed in healthy subjects. METHODS In the first study, all 142 subjects previously exposed to 3MED UVB were invited for a clinical evaluation of PIH. In the second study, 18 healthy subjects were exposed to 2MED UVB, and heat pain detection threshold (PDT) and PIH were evaluated. RESULTS In total, 78 of the 142 subjects responded. The prevalence of PIH among responders was 53.8%. In the second study, we found a significant and stable difference in PDT between UVB-exposed and control skin 3 hr after irradiation; 13 hr post-irradiation, the least squares mean estimate of the difference in PDT ranged from -2.6°C to -4.5°C (p < 0.0001). Finally, the prevalence of PIH was lower in the 2MED group compared to the 3MED group. CONCLUSIONS The 3MED model is associated with a relatively high prevalence of long-lasting PIH. In contrast, 2MED exposure produces stable hyperalgesia and has a lower risk of PIH and is therefore recommended for modelling inflammatory pain. SIGNIFICANCE Postinflammatory Hyperpigmentation is an unwanted long-term side effect associated with the UVB inflammation model using the 3× minimal erythema dose (3MED) paradigm. In contrast, using a 2MED paradigm results in hyperalgesia that is stable for 36 hr and has a lower risk of inducing Postinflammatory Hyperpigmentation.
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The ultraviolet B inflammation model: Postinflammatory Hyperpigmentation and validation of a reduced UVB exposure paradigm for inducing hyperalgesia in healthy subjects.
European Journal of Pain, 2019Co-Authors: Pieter S Siebenga, Guido Van Amerongen, Erica S Klaassen, Marieke L De Kam, Robert Rissmann, G J GroeneveldAbstract:BACKGROUND Pain models are commonly used in drug development to demonstrate analgesic activity in healthy subjects and should therefore not cause long-term adverse effects. The ultraviolet B (UVB) model is a model for inflammatory pain in which three times the minimal erythema dose (3MED) is typically applied to induce sensitization. Based on reports of long-lasting Postinflammatory Hyperpigmentation (PIH) associated with 3MED, it was decided to investigate the prevalence of PIH among subjects who were previously exposed to 3MED at our research centre. In addition, re-evaluation of the UVB inflammation model using a reduced exposure paradigm (2MED) was performed in healthy subjects. METHODS In the first study, all 142 subjects previously exposed to 3MED UVB were invited for a clinical evaluation of PIH. In the second study, 18 healthy subjects were exposed to 2MED UVB, and heat pain detection threshold (PDT) and PIH were evaluated. RESULTS In total, 78 of the 142 subjects responded. The prevalence of PIH among responders was 53.8%. In the second study, we found a significant and stable difference in PDT between UVB-exposed and control skin 3 hr after irradiation; 13 hr post-irradiation, the least squares mean estimate of the difference in PDT ranged from -2.6°C to -4.5°C (p
Kotaro Yoshimura - One of the best experts on this subject based on the ideXlab platform.
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a prospective randomized controlled study of oral tranexamic acid for preventing Postinflammatory Hyperpigmentation after q switched ruby laser
Dermatologic Surgery, 2011Co-Authors: Harunosuke Kato, Jun Araki, Hitomi Eto, Kentaro Doi, Rintaro Hirai, Shinichiro Kuno, Takuya Higashino, Kotaro YoshimuraAbstract:BACKGROUND Postinflammatory Hyperpigmentation (PIH) is the most common skin complication in Asians after invasive cosmetic treatments. OBJECTIVE To determine whether oral tranexamic acid (TA) reduces the incidence of PIH after Q-switched ruby laser (QSRL) treatment. METHODS AND MATERIALS Thirty-two Japanese women underwent QSRL treatment for senile lentigines on the face. They were randomly divided into two groups that did (n=15) and did not (n=17) receive oral TA treatment (750 mg/d) for the first 4 weeks after QSRL treatment. Nineteen participants had melasma-like maculae at baseline. Clinical and colorimetric assessments were performed at baseline and 2 and 4 weeks later. RESULTS Pigmentation was effectively treated using QSRL at 2 weeks, but PIH was frequently seen at 4 weeks. There was no significant difference in the incidence of PIH between participants who received oral TA and those who did not. The presence of melasma did not influence the effectiveness of the treatment. CONCLUSION Although oral TA has been reported to have depigmentation effects, it may not be effective for preventing PIH after QSRL. Considering the dosage and duration of treatment, an optimal protocol may be needed to induce the efficacy of this treatment to achieve the PIH-preventing effect of oral TA.
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A Prospective Randomized Controlled Study of Oral Tranexamic Acid for Preventing Postinflammatory Hyperpigmentation After Q‐Switched Ruby Laser
Dermatologic Surgery, 2011Co-Authors: Harunosuke Kato, Jun Araki, Hitomi Eto, Kentaro Doi, Rintaro Hirai, Shinichiro Kuno, Takuya Higashino, Kotaro YoshimuraAbstract:BACKGROUND Postinflammatory Hyperpigmentation (PIH) is the most common skin complication in Asians after invasive cosmetic treatments. OBJECTIVE To determine whether oral tranexamic acid (TA) reduces the incidence of PIH after Q-switched ruby laser (QSRL) treatment. METHODS AND MATERIALS Thirty-two Japanese women underwent QSRL treatment for senile lentigines on the face. They were randomly divided into two groups that did (n=15) and did not (n=17) receive oral TA treatment (750 mg/d) for the first 4 weeks after QSRL treatment. Nineteen participants had melasma-like maculae at baseline. Clinical and colorimetric assessments were performed at baseline and 2 and 4 weeks later. RESULTS Pigmentation was effectively treated using QSRL at 2 weeks, but PIH was frequently seen at 4 weeks. There was no significant difference in the incidence of PIH between participants who received oral TA and those who did not. The presence of melasma did not influence the effectiveness of the treatment. CONCLUSION Although oral TA has been reported to have depigmentation effects, it may not be effective for preventing PIH after QSRL. Considering the dosage and duration of treatment, an optimal protocol may be needed to induce the efficacy of this treatment to achieve the PIH-preventing effect of oral TA.