Treatment Of Pigmentary Disorders Research Articles

Effects of CE Ferulic® Combined with Microneedling in the Treatment of Pigmentary Disorders: A Monocentric, Split Face, Comparative Study

Pigmentary disorders of the face present a significant challenge in dermatology, impacting the confidence and well-being of affected individuals. Various approaches have been developed to address these concerns, including microneedling and topical vitamin C products. This study involved 15 participants undergoing three treatment sessions over 12 weeks, assessing the efficacy of a combined microneedling and CE Ferulic® serum approach. Clinical evaluation and statistical analysis were conducted before and after the intervention. Significant improvement of akin hyperpigmentation was observed, particularly on the side treated with microneedling and CE Ferulic® serum compared to microneedling alone. The integrated treatment protocol demonstrated a synergistic effect in improving skin texture and appearance. Integrated treatment protocols, such as combining microneedling with CE Ferulic® serum, show promise in managing facial hyperpigmentation disorders. Further research with larger cohorts is warranted to validate these findings and optimize treatment strategies, highlighting the potential of combined therapeutic modalities for achieving optimal clinical outcomes in pigmentary disorder management.

Comparison of the picosecond and Q-switched Nd:YAG lasers in the treatment of pigmentary disorders: a retrospective case series in the Republic of Korea

Comparison of the picosecond and Q-switched Nd:YAG lasers in the treatment of pigmentary disorders: a retrospective case series in the Republic of Korea

Extracts from European Propolises as Potent Tyrosinase Inhibitors.

Tyrosinase is a key enzyme in the melanogenesis pathway. Melanin, the product of this process, is the main pigment of the human skin and a major protection factor against harmful ultraviolet radiation (UVR). Increased melanin synthesis due to tyrosinase hyperactivity can cause hyperpigmentation disorders, which in consequence causes freckles, age spots, melasma, or postinflammatory hyperpigmentation. Tyrosinase overproduction and hyperactivity are triggered by the ageing processes and skin inflammation as a result of oxidative stress. Therefore, the control of tyrosinase activity is the main goal of the prevention and treatment of pigmentation disorders. Natural products, especially propolis, according to their phytochemical profile abundant in polyphenols, is a very rich resource of new potential tyrosinase inhibitors. Therefore, this study focused on the assessment of the tyrosinase inhibitory potential of six extracts obtained from the European propolis samples of various origins. The results showed the potent inhibitory activity of all tested propolis extracts towards commercially available mushroom tyrosinase. The four most active propolis extracts showed inhibitory activity in the range of 86.66-93.25%. Apart from the evaluation of the tyrosinase inhibition, the performed research included UHPLC-DAD-MS/MS (ultra high performance liquid chromatography coupled with diode array detection and tandem mass spectrometry) phytochemical profiling as well as antioxidant activity assessment using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the 2,2"-azino-bis(3-ethylbenzothiazoline-6-sulfuric acid (ABTS) radical scavenging tests. Moreover, statistical analysis was used to correlate the tyrosinase inhibitory and antioxidant activities of propolis extracts with their phytochemical composition. To summarise, the results of our research showed that tested propolis extracts could be used for skin cosmeceutical and medical applications.

Proposal of facial pigmentary unit and facial hyperpigmentation type for Fitzpatrick skin types II-IV.

Studies on facial hyperpigmentation across different facial units are limiting. We aimed to analyze melanin pigmentation images to observe facial pigmentary demarcation lines (FPDLs) and suggest facial hyperpigmentation types for normal individuals. 3D facial melanin pigmentation images of 173 volunteers were obtained and analyzed for the presence of FPDLs. Pigmentation severity was assessed for each of the thirteen facial pigment units. The images were then grouped according to a pattern of hyperpigmentation to suggest three facial hyperpigmentation types-dark spot, photoaging and post-inflammatory hyperpigmentation. Four groups of FPDLs including a novel group I were observed. Nasal, frontal, auricular were the darkest pigmented facial pigment unit, and the anterior neck was the least pigmented. The dark spot type was the most common facial hyperpigmentation type. The photoaging type and the PIH type showed age-dependent distribution, as the photoaging type was more common among the subjects over 40s, and the PIH type was more common in younger subjects. Facial hyperpigmentation among healthy individuals with Fitzpatrick skin types II-IV is often accompanied by FPDLs and categorized into three types. Each type is modeled after the pattern of pigmentation associated with certain dermatological disorders. The practical implications of facial hyperpigmentation types can be resourceful in various fields including prevention and treatment of pigmentary disorders.

Clinical Role of Oral Vitamin C and E Therapy in Skin and Hair Disorders

Clinical Role of Oral Vitamin C and E Therapy in Skin and Hair Disorders

LATS1 Is a Mediator of Melanogenesis in Response to Oxidative Stress and Regulator of Melanoma Growth.

The LATS1 kinase has been described as a tumor suppressor in various cancers. However, its role in melanoma has not been fully elucidated. There are several processes involved in tumorigenesis, including melanin production. Melanin content positively correlates with the level of reactive oxygen species (ROS) inside the cell. Accordingly, the purpose of the study was to assess the role of LATS1 in melanogenesis and oxidative stress and its influence on tumor growth. We have knocked down LATS1 in primary melanocytes and melanoma cells and found that its expression is crucial for melanin synthesis, ROS production, and oxidative stress response. We showed that LATS1 ablation significantly decreased the melanogenesis markers’ expression and melanin synthesis in melanocyte and melanoma cell lines. Moreover, silencing LATS1 resulted in enhanced oxidative stress. Reduced melanin content in LATS1 knocked down tumors was associated with increased tumor growth, pointing to melanin’s protective role in this process. The study demonstrated that LATS1 is highly engaged in melanogenesis and oxidative stress control and affects melanoma growth. Our results may find the implications in the diagnosis and treatment of pigmentation disorders, including melanoma.

Photoablative cosmetic iridoplasty: effective, safe, and predictable\u2014eye color change in 1176 eyes

PurposeTo evaluate photoablative cosmetic iridoplasty (PCI), and its efficacy, safety, predictability, and satisfaction with the 532 nm Crystal Q-switched Nd: Yag laser, with 3–4 ns pulses, for depigmentation of the anterior epithelium of the iris in cases of heterochromia, nevus, or cosmetic indications (eye color change).DesignProspective clinical study on efficacy, safety, predictability, and satisfaction.MethodThe selection of patients was carried out in healthy individuals, over 18 years of age, with iris heterochromia (congenital-7% or acquired, secondary to topical medication-1%, trauma-0.5% or surgery-0.25%), nevus-0.25% and cosmetic cases-91%. Data were collected independently by assistant optometrists and classified in database. Excel statistical program was used to perform a general descriptive study, calculation of correlation factors, and statistical significance analysis between quantitative variables (Student T Test). PCI was performed in 1176 eyes of 588 patients. The procedures were planned in 2–3 phases of 4 consecutive sessions spaced 4–6 months apart. The IRÎZ® (Eyecos®) scanner was used to evaluate the cases, with photography, optical coherence tomography, and pneumotonography modules, along with the following software programs: Predictor®, Simulator® 3D, Analyzer® and Planner® (Eyecos®).ResultsThis study began in 2012, so far 9 years of follow-up, to compare and choose the most suitable among 4 types of lasers to perform cosmetic iridoplasty. Finally, after 5 years, the Crystal Q-switched Nd: Yag at double frequency (532 nm) with 3–4 ns pulses demonstrated the highest efficacy, safety and predictability, so since early 2017 only this equipment has been used. Significant differences were found after 5-year follow-up between 1064, 532, 577 and 532/3–4 ns p = 0.09172, 0.06377 and 0.10183. From 9 January 2017 to 28 February 2020, 1176 eyes have been treated in 588 patients, with a mean age of 33.7 years (SD = 9.68 years, range = 18–70 years). 46.2% were male, and 53.7% were female. The efficacy, as quantified with the Analyzer® comparison software, was nearly 87–95%. There were no significant differences in corrected vision (9 years total follow-up p = 0.78235; last 4 years FU p = 0.99999) and ocular pressure (9 years total FU p = 0.68251; last 4 years FU p = 0.63204) before and after the procedure. The only notable complications (25%) were delayed and brief iritis, which were self-limited with routine topical treatment. The predictability was 80–90%. In the lightest-colored eyes, turquoise blue colors were obtained as a rule, in varying brightness; and in the darkest ones, gray blue tones of varying lightness. The patients’ subjective satisfaction at the end of treatment was 95%.ConclusionAfter 9 years of uninterrupted follow-up, PCI has demonstrated a high effectiveness to selectively depigment superficial melanin of iris, with a high predictability and patient satisfaction, without remarkable long-term complications. Only for a week, appropriate pre- and postoperative medication was necessary to guarantee the absence of discomfort, thus confirming security. PCI is effective, safe, and predictable for the treatment of pigmentary disorders in the iris and for the elective cosmetic indications in eye color change.

16921 Comparison of low-fluence picosecond 1064-nm Nd:YAG laser and picosecond 532-nm Nd:YAG laser in the treatment of pigmentary disorders in Asians: A retrospective analysis

Background: Low-fluence picosecond (LFPS) 1064 nm neodymium: yttrium-aluminum-garnet (Nd:YAG), also known as laser toning, is attracting attention in treatment of pigmented disorders in Asian skin phenotype.

Treatment of pigmentation disorders in association with systemic diseases

Pigmentation disorders are a frequent skin problem and incorporate a broad spectrum of diseases, caused by an abnormal melanin pigmentation or also non-melanin pigmentation of the skin. Both hypermelanosis and hypomelanosis can be hereditary or acquired. This article summarizes the treatment approaches that are used in the majority of acquired pigmentation disorders of the skin. The following forms of hypermelanosis are addressed: lentiginosis, hyperpigmentation due to endocrine disorders or other systemic diseases, drug-induced hyperpigmentation. Acquired hypomelanoses include postinflammatory hypomelanosis, chemical depigmentation, idiopathic guttate hypomelanosis and punctate leucoderma. With reference to non-melanin pigmentation, the exogenous pigmentation due to chemicals, metals and drug exposure are discussed. The treatment is primarily based on finding the cause of the alterations to the pigment. The affected area, age and ethnic origin are also important factors. The spectrum of therapeutic options is broad: topical agents, chemical peeling, systemic agents, laser and light-based treatment. As some of these treatment procedures can have side effects, the availability of a protocol that contains information on the drug concentration, dose, parameters for laser treatment and the number of sessions is important. For every disorder the specific dermatological treatment is presented even when some pigmentation alterations that occur in association with systemic diseases, are cured by the treatment of the primary disease. Most diseases are exacerbated by exposure to UV light. Therefore, sun protection is recommended and a cosmetic coverage is indicated.

Micro Needle Peel: Microneedling Associated to with Chemical Peel in the Treatment of Pigmentation Disorders

Micro Needle Peel: Microneedling Associated to with Chemical Peel in the Treatment of Pigmentation Disorders

Tyrosinase inhibition and anti-melanin generation effect of cinnamamide analogues

Abnormal melanogenesis results in excessive production of melanin, leading to pigmentation disorders. As a key and rate-limiting enzyme for melanogenesis, tyrosinase has been considered an important target for developing therapeutic agents of pigment disorders. Despite having an (E)-β-phenyl-α,β-unsaturated carbonyl scaffold, which plays an important role in the potent inhibition of tyrosinase activity, cinnamic acids have not attracted attention as potential tyrosinase inhibitors, due to their low tyrosinase inhibitory activity and relatively high hydrophilicity. Given that cinnamic acids’ structure intrinsically features this (E)-scaffold and following our experience that minute changes in the chemical structure can powerfully affect tyrosinase activity, twenty less hydrophilic cinnamamide derivatives were designed as potential tyrosinase inhibitors and synthesised using a Horner-Wadsworth-Emmons reaction. Four of these cinnmamides (4, 9, 14, and 19) exhibited much stronger mushroom tyrosinase inhibition (over 90% inhibition) at 25 µM compared to kojic acid (20.57% inhibition); crucially, all four have a 2,4-dihydroxy group on the β-phenyl ring of the scaffold. A docking simulation using tyrosinase indicated that the four cinnamamides exceeded the binding affinity of kojic acid, and bound more strongly to the active site of tyrosinase. Based on the strength of their tyrosinase inhibition, these four cinnamamides were further evaluated in B16F10 melanoma cells. All four cinnamamides, without cytotoxicity, exhibited higher tyrosinase inhibitory activity (67.33 – 79.67% inhibition) at 25 μM than kojic acid (38.11% inhibition), with the following increasing inhibitory order: morpholino (9) = cyclopentylamino (14) < cyclohexylamino (19) < N-methylpiperazino (4) cinnamamides. Analysis of tyrosinase activity and melanin content in B16F10 cells showed that the four cinnamamides dose-dependently inhibited both cellular tyrosinase activity and melanin content and that their inhibitory activity at 25 μM was much better than that of kojic acid. The results of melanin content analysis well matched those of the cellular tyrosinase activity analysis, indicating that tyrosinase inhibition by the four cinnamamides is a major factor in the reduction of melanin production. These results imply that these four cinnamamides with a 2,4-dihydroxyphenyl group can act as excellent anti-melanogenic agents in the treatment of pigmentation disorders.

Resveratrol as a Multifunctional Topical Hypopigmenting Agent.

Melanin is produced in melanocytes and stored in melanosomes, after which it is transferred to keratinocytes and, thus, determines skin color. Despite its beneficial sun-protective effects, abnormal accumulation of melanin results in esthetic problems. A range of topical hypopigmenting agents have been evaluated for their use in the treatment of pigmentary disorders with varying degrees of success. Hydroquinone (HQ), which competes with tyrosine, is the main ingredient in topical pharmacological agents. However, frequent occurrence of adverse reactions is an important factor that limits its use. Thus, efforts to discover effective topical hypopigmenting agents with less adverse effects continue. Here, we describe the potential of resveratrol to function as an effective hypopigmenting agent based on its mechanism of action. Resveratrol is not only a direct tyrosinase inhibitor but an indirect inhibitor as well. Additionally, it can affect keratinocytes, which regulate the function of melanocytes. Resveratrol regulates the inflammatory process of keratinocytes and protects them from oxidative damage. In this way, it prevents keratinocyte-induced melanocyte stimulation. Furthermore, it has a rescuing effect on the stemness of interfollicular epidermal cells that can repair signs of photoaging in the melasma, a typical pigmentary skin disorder. Overall, resveratrol is a promising potent hypopigmenting agent.

Evolution of the Picosecond Laser: A Review of Literature.

Picosecond pulse duration lasers (PS) have altered the field of dermatology. PS were initially used in tattoo removal, to optimize efficacy and reduce side effects with nanosecond domain lasers. More recently, they have been demonstrated to be effective in the treatment of pigmentary disorders, acne scarring, and photoaging. In this article, we critically analyze the published data on the many uses of picosecond lasers in dermatology. A systematic review of PubMed was conducted using the following search terms: "picosecond," "picosecond laser," "picosecond laser dermatology," "picosecond laser pigment/pigmentation," and "picosecond laser tattoo removal." Articles ranged from 1988 until 2017. Forty-one articles were identified, and 27 met inclusion criteria for review. Indications for the PS included a variety of dermatologic applications include tattoo removal, benign pigmented lesions/pigmentary disorders, acne scarring, and photoaging. Most studies demonstrated safe and effective treatment. The development of the picosecond pulse duration is a breakthrough innovation in laser technology, changing the scope of laser treatment. Encouraging findings in tattoo pigment clearance spurred the use of PS in a wider array of dermatologic issues. The increasingly positive results and low incidence of adverse effects further substantiates PS efficacy for a variety of dermatologic uses.

Chemical Peeling with a Modified Phenol Formula for the Treatment of Facial Freckles on Asian Skin.

Chemical peeling is an efficient method for the treatment of pigment disorders. For freckles, medium-depth to deep peeling using a phenol solution is one of the most effective chemical peels, and modifications of facial skin can be observed up to 20years after peeling. However, applying phenol to the skin may cause serious side effects. Phenol peeling has been rarely used in Asia due to its tendency to cause permanent pigmentary changes and hypertrophic scars. In total, 896 Chinese inpatients with facial freckles were enrolled in this study. The phenol formula was modified with crystalline phenol, dyclonine, camphor, anhydrous alcohol and glycerin and adjusted to a concentration of 73.6-90.0%. The entire peeling treatment was divided into two procedures performed separately on 2days. All patients exhibited 26% or greater improvement, and 99.66% of patients exhibited 51% or greater improvement (good and excellent). Scarring and systemic complications were not observed in any patient. The modified phenol formula is very effective and safe for the treatment of facial freckles in Asian patients. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Quercetin as a tyrosinase inhibitor: Inhibitory activity, conformational change and mechanism

Quercetin, a flavonoid compound, was found to inhibit both monophenolase and diphenolase activities of tyrosinase, and its inhibition against diphenolase activity was in a reversible and competitive manner with an IC50 value of (3.08±0.74)×10−5molL−1. Quercetin bound to tyrosinase driven by hydrophobic interaction, thereby resulted in a conformational change of tyrosinase and its intrinsic fluorescence quenching. Tyrosinase had one binding site for quercetin with the binding constant in the order of magnitude of 104Lmol−1. The molecular docking revealed that quercetin bound to the active site of tyrosinase and chelated a copper with the 3′, 4′-dihydroxy groups. It can be deduced that the chelation may prevent the entrance of substrate and then inhibit the catalytic activity of tyrosinase. These findings may be helpful to understand the inhibition mechanism of quercetin on tyrosinase and functional research of quercetin in the treatment of pigmentation disorders.

Treatment of pigmentary disorders in patients with skin of color with a novel 755 nm picosecond, Q‐switched ruby, and Q‐switched Nd:YAG nanosecond lasers: A retrospective photographic review

Laser procedures in skin of color (SOC) patients are challenging due to the increased risk of dyspigmentation and scarring. A novel 755 nm alexandrite picosecond laser has demonstrated effectiveness for tattoo removal and treatment of acne scars. No studies to date have evaluated its applications in pigmentary disorders. The purpose of this retrospective study was to evaluate the safety profile and efficacy of the picosecond alexandrite laser compared to the current standard treatment, Q-switched ruby and neodynium (Nd):YAG nanosecond lasers, for pigmentary disorders in SOC patients. A retrospective photographic and chart evaluation of seventy 755 nm alexandrite picosecond, ninety-two Q-switched frequency doubled 532 nm and 1,064 nm Nd:YAG nanosecond, and forty-seven Q-switched 694 nm ruby nanosecond laser treatments, in forty-two subjects of Fitzpatrick skin types III-VI was conducted in a single laser specialty center. The picosecond laser was a research prototype device. Treatment efficacy was assessed by two blinded physician evaluators, using a visual analog scale for percentage of pigmentary clearance in standard photographs. Subject assessment of efficacy, satisfaction, and adverse events was performed using a questionnaire survey. The most common pigmentary disorder treated was Nevus of Ota (38.1%), followed by solar lentigines (23.8%). Other pigmentary disorders included post-inflammatory hyperpigmentation, congenital nevus, café au lait macule, dermal melanocytosis, Nevus of Ito, and Becker's nevus. Clinical efficacy of the Q-switched nanosecond lasers and picosecond laser treatments were comparable for lesions treated on the face with a mean visual analog score of 2.57 and 2.44, respectively, corresponding to approximately 50% pigmentary clearance. Subject questionnaires were completed in 58.8% of the picosecond subjects and 52.0% of the Q-switched subjects. Eighty four percent of subjects receiving Q-switched nanosecond laser treatments and 50% of the subjects receiving alexandrite 755 nm picosecond laser treatments felt satisfied to completely satisfied. Side effects observed in subjects treated with the alexandrite 755 nm picosecond laser were similar to those commonly observed and reported with the nanosecond Q-switched technology. All side effects were temporary, resolving within one month, and no long-term complications were noted. All patients who were very satisfied with their picosecond laser treatment for Nevus of Ota noted a delayed improvement only after 3 months. The 755 nm alexandrite picosecond, 694 nm ruby, 532 nm, and 1064 nm neodynium:YAG nanosecond lasers appear to be safe and effective modalities for removal of pigmentary disorders in skin of color patients with no long-term complications if used appropriately. This study demonstrates the potential of the 755 nm alexandrite picosecond laser in further clinical applications beyond tattoo removal. While the Q-switched lasers were effective, promising results were also observed using an early version of the novel picosecond laser for the removal of pigmentary lesions in SOC patients. As we continue to improve our understanding of the 755 nm picosecond laser, this device may prove to be a safe and effective alternative to the Q-switched lasers for the treatment of facial pigmented lesions in patients with skin of color.

(Z)-2-(Benzo[d]thiazol-2-ylamino)-5-(substituted benzylidene)thiazol-4(5H)-one Derivatives as Novel Tyrosinase Inhibitors.

Inhibiting tyrosinase is an important goal to prevent melanin accumulation in skin and thereby to inhibit pigmentation disorders. Therefore, tyrosinase inhibitors are an attractive target in cosmetics and treatments for pigmentation disorders. However, only a few tyrosinase inhibitors are currently available because of their toxic effects to skin or lack of selectivity and stability. Here, we newly synthesized thirteen (Z)-2-(benzo[d]thiazol-2-ylamino)-5-(substituted benzylidene)thiazol-4(5H)-one derivatives and examined their effect on melanogenesis. Of these compounds, MHY2081 had the strongest inhibitory effect on tyrosinase without cytotoxicity in B16F10 melanoma cells. Consistently, melanogenesis was notably decreased by MHY2081 treatment. As an underlying mechanism, docking simulation showed that compared to kojic acid, a well-known competitive tyrosinase inhibitor which forms a hydrogen bond and aromatic interaction with tyrosinase, MHY2081 has stronger affinity with tyrosinase by forming three hydrogen bonds and a hydrophobic interaction with residues of tyrosinase. In parallel with this, Lineweaver-Burk plot analysis showed that MHY2081 is a strong competitive inhibitor of tyrosinase. In conclusion, MHY2081 may be a novel tyrosinase inhibitor for prevention and treatment of pigmentation disorders.

Inhibition of melanogenesis by 2-[4-(5-chlorobenzo[d]thiazol-2-yl)phenoxy]-2-methylpropanoic acid (MHY908).

Tyrosinase inhibitors might have potential use in cosmetic and medicinal products for the prevention of pigmentation disorders. However, only a few inhibitors are currently used due to their cytotoxicity, and lack of selectivity and stability. In this study, we synthesized several tyrosinase inhibitors and investigated their activity. To investigate the action of 2-[4-(5-chlorobenzo[d]thiazol-2-yl)phenoxy]-2-methylpropanoic acid (MHY908) specifically in the inhibition of melanogenesis, a mushroom tyrosinase activity assay was performed. We confirmed the inhibitory effect of MHY908 at various melanin concentrations using α-MSH-induced melanoma cells. Our results indicate that MHY908 potently inhibited mushroom tyrosinase activity (IC50=8.19μM) in a dose-dependent manner. Through a docking simulation, we also analyzed its binding mode to inhibit tyrosinase activity. MHY908 also decreased melanin synthesis without inducing cytotoxicity. These results suggest that MHY908 is a good candidate for prevention and treatment of pigmentation disorders.

Q-Switched Neodymium-Doped Yttrium Aluminum Garnet Laser Therapy for Pigmented Skin Lesions: Efficacy and Safety

Nepalese population with Fitzpatrick skin types III-V has high prevalence of pigmentary disorders and it is a growing cosmetic concern. Q-Switched Neodymium- Doped Yttrium Aluminum Garnet (QS Nd-YAG) laser is an efficacious tool in the treatment of pigment disorders. To highlight the efficacy and safety profile of various pigment disorders. A prospective study done in Dhulikhel Hospital, Kathmandu University Hospital from January 2009 to January 2011. Patients undergoing laser for pigmented skin lesions were followed for response and safety profile. We included total 270 patients in the study with various disorders especially nevus, tattoos and melasma. Settings were repeated at 3-4 weeks interval and response was evaluated on clinical basis. Efficacy was then evaluated according to various parameters. For nevus, total 840 treatment sessions had been performed with an average of 6.88 sessions (range 3-11). Nd: YAG laser was very efficacious in removal of blue and black colored tattoos with an average of 7.9 and 9.5 sessions respectively. However, red mixed with blue and or green tattoos were relatively resistant to treatment and required average 10.33 treatment sessions. Melasma and freckles both responded to the therapy but recurrence rate was high. Our results indicate that QS Nd: YAG laser is an effective modality for pigment disorders among Nepalese population. Nevus and melasma respond well but recurrence rate of melasma is high. Blue tattoos respond well while mixed colored tattoos are quite resistant to Nd: YAG laser alone. Transient pain and temporary hyperpigmentation are common side effects.

Disorders of Pigmentation

Skin color is highly individual and the variations are controlled by numerous genes. The different skin colors result from the size and number of melanosomes and do not mirror the amount of melanocytes. Disorders of pigmentation can result from migration abnormalities of melanocytes from the neural crest to the skin during embryogenesis. In addition, impairment of melanosome transfer to the surrounding keratinocytes, an alteration in melanin synthesis and a defective degradation or removal of melanin may lead to abnormal skin pigmentation. Immunologic or toxic mediated destructions of melanocytes can end in pigmentation disorders. Disorders of pigmentation are classified in hypo- or hyperpigmentation which can occur as a genetic or acquired disease. They can manifest locally or diffuse. Congenital hypopigmentation can be restricted to the skin as in piebaldism or they represent a systemic disease as in Menkes disease or phenylketonuria. Localized hypo- or hyperpigmentation in children may serve as markers for systemic diseases. Ash-leaf hypopigmentation are characteristic for tuberous sclerosis and more than 5 café-au-lait spots suggest neurofibromatosis 1 (von Recklinghausen disease). The most common autoimmune-induced depigmentation is vitiligo. Generalized hyperpigmentation only rarely reflects a primary genetic disorder but is most often from acquired diseases as in Addison disease, secondary hemochromatosis or primary biliary cirrhosis. Treatment of pigmentation disorders are based on a diagnosis which sometimes allow a specific intervention. Cosmetically acceptable results are difficult to obtain.