Facial Pigmentation

Author : Dr. Vibhu Mendiratta

Face is the key to fortune as the old saying goes. The saying becomes further more relevant in the present day times as possessing attractive external persona and cosmetic appeal have become essential for professional and personal success . A tiny facial blemish or an innocuous spot , scar or imperfection can shatter self esteem or erode the confidence of an individual thus resulting in poor quality of life.

Nature has blessed Asian skin with color which protects us from the harmful effects of UV light and helps in vitamin D synthesis . Skin Color is contributed by – melanin, hemoglobin and carotenoids , former being the most important determinant of skin color. All races have equal number of color producing cells known as melanocytes irrespective of their skin color, however it is the size and arrangement of these tiny sacs which carry the melanin pigment in them ( melanosomes) that determines the final color of skin. Caucasians or white races have smaller melanosomes which lie in one place in contrast to the darker races which have larger melanosomes that lie scattered throughout the pigment cell . The “pigment factory “ or the melanocytes lie in the superficial layer of skin called the epidermis . The production of melanin depends on several external and internal factors. The melanocytes can be easily stimulated to produce more melanin by ultraviolet rays in the sun light, frictional force on skin, chemical injury , hormonal changes during pregnancy , drugs , autoimmune diseases such as thyroid etc.

Facial hyperpigmentation implies pigmentation or darkening of skin involving predominantly the face and the neck . Pigmentation is quite common in Indians and often turns out to be a complex diagnostic problem. Genetic and racial factors are important.

Causes of facial pigmentation can be broadly classified into

• Congenital- Refers to conditions that are usually present at birth or appear in the first few years of life. Some of them are familial namely melanocytic naevi or the pigmented moles while others are isolated abnormalities. Pigmentation can only be limited to skin or it may be associated with abnormalities in brain, eyes, ears , teeth and the musculoskeletal systems . Pigmented moles, cafe- au-lait macules, lentigines are some common spotty pigmentary problems which may involve the face.
• Acquired – Comprises of conditions that appear later on in life . The cause may be genetic but is external in most of the cases. Pigmentation may be progressive, may show gradual darkening and spread to other areas , may have associated symptoms like photosensitivity , itching , burning etc. Establishing the cause in acquired pigmentation requires a detailed personal history and some lab tests . Melasma, toxic melanosis, pigmented cosmetic dermatitis and post inflammatory and drug induced pigmentation are some common conditions in the Indian scenario.

CONGENITAL :

Naevus of ota- It is a congenitally acquired speckled grayish - blue pigmentation, predominantly involving sclera, conjunctiva, forehead, scalp, alae nasi and ears. The distribution is mainly restricted to distribution of trigeminal nerve. This disorder is most common in Asian people.It is usually not visible at birth, but become progressively darker in childhood and persist in adult life.

Café- au lait macules ( CALMS)- Are flat, brownish macules which are well marginated and the size may vary from .5mm to > 1.5 mm. Number can be variable ( one – many) . More than 6 CALMS > 1.5 mm are indicative of Neurofibromatosis
.
Conginatal melanocytic naevus- Are brownish to grayish –blue patches, plaques or papules . They may be small in size or as large as 20 cm. Some of these show excessive localized hair growth ( hypertrichosis) . These moles show increased skin rugosity with time , darkening of color and giant naevi may also develop melanoma.

ACUIRED CONDITIONS

• PATCHY PIGMENTATION / SPOTS

EPHILEDS/FRECKELS- It is a light colored , poorly defined , pale brown, macular lesion, usually less than 3mm in diameter which appears on sun exposed sites such as face , arms and hands during period of UV exposure.It is commonly seen in individuals who have red or light colored skin and hair. Freckles concentrate over the centrofacial area and tend to fade or become lighter in winter months.

LENTIGINES-These are also hyperpigmented macular skin lesions which occur over both exposed and the sun protected areas namely face, extremities, trunk and mucosae . Lentigines persist throughout the year and do not fade away as . there is an increased proliferation of melanocytes in response to sun exposure in faired skinned people. Lentiginosis may be seen in some inherited genetic syndromes like Peutz- Jegher’s syndrome, Cronkhite- Canada syndrome where lentiginosis is seen in association with intestinal polyps.

• DIFFUSE PIGMENTATION

MELASMA: It is also known as mask of pregnancy. It is a multifactorial disorder and can be seen in anemia, thyroid gland dysfunction, after anticonvulsant and oral contraceptive therapy . This common acquired facial hypermelanosis is seen in both men and women but is more common in the latter. It occurs mainly in sun exposed facial skin , occasionally affecting the forearms. Many cases are attributed to pregnancy . It is not uncommon at any time during the years of reproductive activity and has been attributed, without acceptable proof, to a variety of ovarian disorders. It affects the upper lip, cheeks, forehead and chin and is more apparent following sun exposure. Melasma can be superficial ( epidermal ) or mixed ( epidermal – dermal ) or dermal when the pigmentation is in the dermis . Dermal melasma appears grayish blue in color and is quite challenging to treat. In superficial melasma, the affected skin is brown in colour. The pigmentary changes are seen over the cheeks, nose, forehead and the chin. Melasma is usually bilateral .

RIEHL’S MELANOSIS– It is a distinctive pattern of grey-brown facial pigmen- tation. The condition is more frequent in women. Exposure to industrial solvents containing tar derivatives, photosensitizers in cosmetics and fragrances are suspected to be the cause. Brownish-grey pigmentation develops quite rapidly over the greater part of the face but is more intense on the forehead and temples. Smaller pigmented macules, often perifollicular, lie beyond the indefinite margin. The pigmentation may extend to the chest, neck and scalp, and occasionally involves hands and forearms. Horny plugs fill the follicles and there may be some scaling.

OCHRONOSIS-It is a bluish grey pigmentation of skin, due to deposition of homogentisic acid in connective tissue. It can be ether due to exogenous or endogenous cause. Exogenous ochronosis is seen with use of hydroquinone prepration and phenol. Exogenous ochronosis is becoming increasingly common in the modern times due to indiscriminate use of skin lightening creams for a prolonged period . Higher concentrations of hydroquinone ( > 2%) are more likely to cause this pigmentation. Milder cases show only macular spotty pigmentation whilst more advanced cases develop irregular stippling, papulation and pigmented colloid milia. These features tend to be most prominent over cheeks and temples.

LICHEN PLAUS PIGMENTOSUS-This disorder is commonly seen in India and Middle East. The macular hyperpigmentation involves chiefly the face, neck and upper limbs, although it can be more widespread, and varies from slate grey to brownish black; it is mostly diffuse, but reticular, blotchy and perifollicular forms are seen. Mucosal involvement can be seen in some cases.

ADDISONS DISEASE-hyperpigmentation in Addison disease is diffuse brownish colour. Predominantly affect sun exposed part. It is more prominent over the creases of palm and soles. Involvement of mucosa like oral, genital mucosa is common. Other features suggestive of Addison disease should be looked in such cases.The hypermelanosis is the result of increased secretion of melanotrophic hormones by the pituitary. Affected patients have elevated plasma levels of β-MSH-like immunoreactivity.

CUSHING SYNDROME-Pigmentation is of similar pattern as seen in Addison disease. Seen in around 10% patient of cushing syndrome. It results from increased secretion of ACTH and β-MSH by the pituitary and may suggest the presence of a pituitary tumour. The hair is often darker and there are sometimes multiple lentigines and longitudinal pigmented bands in the nails.

HYPERTHYROIDISM- Facial Pigmentation is seen in about 10% cases of primary thyrotoxicosis. It can be diffuse Addisonian like pigmentation, but involvement of mucosa, nipple and genitalia is less common.The eyelids are occasionally conspicuously pigmented (Jellinek’s sign). Some patients show chloasmal rather than diffuse pigmentation.

HYPERMELANOSIS ASSOCIATED WITH OTHER SYSTEMIC DISEASE

NEOPLASTIC DISEASE-Oat cell carcinoma of the bronchus is associated with pigmentation due ectopic secretion of ACTH. There will be cachectic state with diffuse pigmentation as in Addison’s disease. There can be diffuse slate grey colour pigmentation secondary to melanoma and melanogenuria.

LYMPHOMA –Diffuse Addisonian pigmentation can be a rare manifestation of Hodgkin’s disease (10%) and 1 or 2% cases of lymphosarcoma and lymphatic leukaemia. Diffuse progressive hyperpigmentation with pigmented purpura like lesion can also be a manifestation of mycosis fungoides.

SYSTEMIC SCLEROSIS, SCLERODERMA AND MORPHOEA- Diffuse pigmentation of face involving predominantly forehead and lateral aspect of cheek and extremity is commonly seen. Reticulate pigmentation of upper back and chest is not uncommon. Along with pigmentation skin is bound down and indurated. Hyperpigmentation in systemic sclerosis is seen most commonly in patients with pigmented skin, and is less common in whites.Keratinocyte endothelin-1 production has been implicated as playing a central role in the pathogenesis of cutaneous hyperpigmentation in systemic sclerosis, as has local expression and systemic release of a stem cell factor.Pigmentation may also be a conspicuous feature of morphoea and is occasionally the presenting symptom.

LUPUS ERYTHEMATOSUS-In systemic lupus erythematosus, diffuse pigmentation of light-exposed skin occurs in about 10% of cases. It may gradually darken, although the disease is controlled by treatment.

RENAL FAILURE –Diffuse hyperpigmentation of face and hand is common in chronic renal disease.

ANAEMIA-Vitamin B 12 deficiency can cause mottle and dapple pigmentation of face, hand and feet. Occasionally folic acid deficiency can cause diffuse pigmentation.

PRIMARY BILIARY CIRRHOSIS-Hyperpigmentation is particularly striking on sun-exposed sites.

APPROACH TO PATIENT
History :

• Ethnicity- pigmentary disorders are more common in fair skinned people
• Onset of pigmentation- congenital / acquired
• Aggravation with sun exposure – present in cases of freckels
• Associated with pregnancy
• History of OCP intake
• History of topical hydroquinone application, application of hair dye
• History of multiple cosmetic usage
• History related to any systemic illness

Treatment

• General measures- Photoprotection, avoidance of aggravating factors(if any)
• Medical treatment-
• Broad spectrum sunscreens
• Hydroquinone 4%- efficacy of treating melasma with 4% hydroquinone, for 3 months, is well demonstrated by placebo controlled trials.

Side effects- local irritation, exogenous ochronosis

• Retinoic acid- 0.1% retinoic acid can be use
• Triple combination- hydroquinone 4%, tretinoin 0.05%, flucinolone acetonide 0.01% (modified kligman’s formula) can be used once at night for melasma, riehls melanosis, and in some cases of lichen planus pigmentosus.

Side effects- burning and irritation, ochronosis(with prolonged application)

• Azelaic acid- 20% azelaic acid as a depigmenting agent, azelaic acid is moderately effective in treatment of melasma.
• Retinoic acid- 0.1% can be used in solar lentigenosis with moderate benefit.
• Lasers- A variety of lasers are available for treating the hyperpigmentation which include Q – switched ruby laser, Erbium Yag Laser .