Melasma (also known as chloasma faciei,James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . or the mask of pregnancy when present in pregnant women) is a tan or dark skin discoloration. Melasma is thought to be caused by sun exposure, genetic predisposition, hormone changes, and skin irritation. Although it can affect anyone, it is particularly common in women, especially pregnant women and those who are taking

oral The word oral may refer to: Relating to the mouth * Relating to the mouth, the first portion of the alimentary canal that primarily receives food and liquid ** Oral administration of medicines ** Oral examination (also known as an oral exam or or ...

or patch

contraceptive Birth control, also known as contraception, anticonception, and fertility control, is the use of methods or devices to prevent unwanted pregnancy. Birth control has been used since ancient times, but effective and safe methods of birth contr ...

s or hormone replacement therapy medications.

Signs and symptoms

The symptoms of melasma are dark, irregular, well-demarcated, hyperpigmented macules to patches. These patches often develop gradually over time. Melasma does not cause any other symptoms beyond the cosmetic discoloration. Patches can vary in size from 0.5 cm to larger than 10 cm depending on the person. Its location can be categorized as centrofacial, malar, or mandibular. The most common is centrofacial, in which patches appear on the cheeks, nose, upper lip, forehead, and chin. The mandibular category accounts for patches on the bilateral rami, while the malar location accounts for patches only on the nose and cheeks.

Cause

The exact cause of melasma is unknown. Melasma is thought to be the stimulation of

melanocyte Melanocytes are melanin-producing neural crest-derived cells located in the bottom layer (the stratum basale) of the skin's epidermis, the middle layer of the eye (the uvea), the inner ear, vaginal epithelium, meninges, bones, and hear ...

s (cells in the dermal layer, which transfer the

pigment A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compou ...

melanin to the keratinocytes of skin) when the skin is exposed to ultraviolet light from the sun. Small amounts of sun exposure can make melasma return to the skin after it has faded, which is why people with melasma often get it again and again, particularly in the summer. Pregnant women often get melasma, or chloasma, known as the mask of pregnancy. Birth-control pills and hormone replacement therapy also can trigger melasma. The discoloration usually disappears spontaneously over a period of several months after giving birth or stopping the oral contraceptives or hormone treatment. Genetic predisposition is also a major factor in determining whether someone will develop melasma. People with the Fitzpatrick skin type III or greater from African, Asian, or Hispanic descent are at a much higher risk than others. In addition, women with a light brown skin type who are living in regions with intense sun exposure are particularly susceptible to developing this condition. The incidence of melasma also increases in patients with

thyroid disease Thyroid disease is a medical condition that affects the function of the thyroid gland. The thyroid gland is located at the front of the neck and produces thyroid hormones that travel through the blood to help regulate many other organs, meaning ...

. It is thought that the overproduction of

melanocyte-stimulating hormone The melanocyte-stimulating hormones, known collectively as MSH, also known as melanotropins or intermedins, are a family of peptide hormones and neuropeptides consisting of α-melanocyte-stimulating hormone (α-MSH), β-melanocyte-stimulating ho ...

brought on by stress can cause outbreaks of this condition. Other rare causes of melasma include allergic reaction to medications and cosmetics.

Addison's disease

Melasma suprarenale (Latin - above the kidneys) is a symptom of

Addison's disease Addison's disease, also known as primary adrenal insufficiency, is a rare long-term endocrine disorder characterized by inadequate production of the steroid hormones cortisol and aldosterone by the two outer layers of the cells of the adrena ...

, particularly when caused by pressure or minor injury to the skin, as discovered by FJJ Schmidt of Rotterdam in 1859.

Diagnosis

Types

The two different kinds of melasma are epidermal and dermal. *Epidermal melasma results from melanin pigment that is elevated in the suprabasal layers of the epidermis. *Dermal melasma occurs when the dermal macrophages have an elevated melanin level. Melasma is usually diagnosed visually or with assistance of a Wood's lamp (340 - 400 nm wavelength). Under Wood's lamp, excess melanin in the epidermis can be distinguished from that of the dermis. This is done by looking at how dark the melasma appears; dermal melasma appears darker than epidermal melasma under the Wood's lamp.

Severity

The severity of facial melasma may be assessed by colorimetry, mexametry, and the melasma area and severity index (MASI) score.

Differential diagnoses

Melasma should be differentiated from freckles, solar lentigo, toxic melanoderma, Riehl's melanosis, post-inflammatory hyperpigmentation, friction melanosis, ochronosis (endogenous and exogenous), cutaneous erythematosus

lupus Lupus, technically known as systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Commo ...

. Additionally, it should not be confused with phytophotodermatosis, pellagra, endogenous phototoxicity,

nevus of Ota Nevus of Ota is a hyperpigmentation that occurs on the face, most often appearing on the white of the eye. It also occurs on the forehead, nose, cheek, periorbital region, and temple. It was first reported by Masao Ōta of Japan in 1939. Cau ...

, ''café au lait'' macules,

seborrheic keratosis A seborrheic keratosis is a non-cancerous (benign) skin tumour that originates from cells, namely keratinocytes, in the outer layer of the skin called the epidermis. Like liver spots, seborrheic keratoses are seen more often as people age. The tu ...

, Civatte's poikiloderma, acquired bilateral nevus of ota-like macules (

Hori's nevus Hori's nevus (also known as "Acquired bilateral nevus of Ota-like macules") is a cutaneous condition characterized by multiple brown–gray to brown–blue macules, primarily in the malar region of the face. See also * Nevus of Ota * List of cut ...

), periorbital hyperpigmentation, erythrose pigmentaire peribuccale of Brocq, erythromelanosis follicularis faciei, facial acanthosis nigricans, and actinic lichen planus. Also, cases of drug-induced pigmentation have been reported, caused by amiodarone, or hydroquinone-induced exogenous ochronosis (see ochronosis treatment)

Treatment

Assessment by a dermatologist can help guide treatment. Treatments to hasten the fading of the discolored patches include: * Topical depigmenting agents, such as

hydroquinone Hydroquinone, also known as benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, a derivative of benzene, having the chemical formula C6H4(OH)2. It has two hydroxyl groups bonded to a benzene ring in a ''pa ...

(HQ) either in over-the-counter (OTC - 2%) or prescription (4%) strength. HQ inhibits tyrosinase, an enzyme involved in the production of

melanin Melanin (; from el, μέλας, melas, black, dark) is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino ...

. *

Tretinoin Tretinoin, also known as all-''trans'' retinoic acid (ATRA), is a medication used for the treatment of acne and acute promyelocytic leukemia. For acne, it is applied to the skin as a cream, gel or ointment. For leukemia, it is taken by mouth f ...

, a

retinoid The retinoids are a class of chemical compounds that are vitamers of vitamin A or are chemically related to it. Retinoids have found use in medicine where they regulate epithelial cell growth. Retinoids have many important functions throughout ...

, increases skin cell (keratinocyte) turnover. This treatment is not used during pregnancy due to risk of harm to the fetus. *

Azelaic acid Azelaic acid (AzA) is an organic compound with the formula HOOC(CH2)7 COOH. This saturated dicarboxylic acid exists as a white powder. It is found in wheat, rye, and barley. It is a precursor to diverse industrial products including polymers a ...

(20%) is thought to decrease the activity of melanocytes. *

Tranexamic acid Tranexamic acid (TXA) is a medication used to treat or prevent excessive blood loss from major trauma, postpartum bleeding, surgery, tooth removal, nosebleeds, and heavy menstruation. It is also used for hereditary angioedema. It is taken ei ...

by mouth has shown to provide rapid and sustained lightening in melasma by decreasing melanogenesis in epidermal melanocytes. *

Cysteamine hydrochloride Cysteamine is a chemical compound that can be biosynthesized in mammals, including humans, by the degradation of coenzyme A. The intermediate pantetheine is broken down into cysteamine and pantothenic acid. It is the biosynthetic precursor to ...

(5%) over-the-counter Mechanism of action seems to involve inhibition of melanin synthesis pathway * Kojic acid (2%) OTC * Flutamide (1%) * Chemical peels * Microdermabrasion to

dermabrasion Dermabrasion is a type of surgical skin planing, generally with the goal of removing acne, scarring and other skin or tissue irregularities, typically performed in a professional medical setting by a dermatologist or plastic surgeon trained speci ...

(light to deep) * Galvanic or ultrasound facials with a combination of a topical crème/gel, either in an aesthetician's office or as a home massager unit *

Laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The ...

but not intense pulsed light (which can make the melasma darker)

Effectiveness

Evidence-based reviews found that the most effective therapy for melasma includes a combination of topical agents. Triple combination creams formulated with

tretinoin Tretinoin, also known as all-''trans'' retinoic acid (ATRA), is a medication used for the treatment of acne and acute promyelocytic leukemia. For acne, it is applied to the skin as a cream, gel or ointment. For leukemia, it is taken by mouth f ...

, and a steroid component have shown to be more effective than dual combination therapy or hydroquinone alone. More recently, a systematic review found that oral medications also have a role in melasma treatment, and have been shown to be efficacious with a minimal number and severity of adverse events. Oral medications and dietary supplements employed in the treatment of melasma include

tranexamic acid Tranexamic acid (TXA) is a medication used to treat or prevent excessive blood loss from major trauma, postpartum bleeding, surgery, tooth removal, nosebleeds, and heavy menstruation. It is also used for hereditary angioedema. It is taken ei ...

, '' Polypodium leucotomos'' extract, beta‐carotenoid,

melatonin Melatonin is a natural product found in plants and animals. It is primarily known in animals as a hormone released by the pineal gland in the brain at night, and has long been associated with control of the sleep–wake cycle. In vertebrat ...

, and procyanidin. Oral procyanidin combined with vitamins A, C, and E shows promise as safe and effective for epidermal melasma. In an 8-week randomized, double-blind, placebo-controlled trial in 56 Filipino women, treatment was associated with significant improvements in the left and right malar regions, and was safe and well tolerated. In all of these treatments, the effects are gradual and a strict avoidance of sunlight is required. The use of broad-spectrum sunscreens with physical blockers, such as titanium dioxide and zinc oxide, is preferred, because UV-A, UV-B, and visible lights are all capable of stimulating pigment production. Many negative side effects can go along with these treatments, and treatments often are unsatisfying overall. Scarring, irritation, lighter patches of skin, and contact dermatitis are all commonly seen. Patients should avoid other precipitants, including hormonal triggers. Cosmetic camouflage can also be used to hide melasma.

References

External links

* {{Infants and their care Disturbances of human pigmentation Human pregnancy