Information
Editors
Skin Colour Changes and Pigmentary Disorders
Essentials
- Pigmentary disorders may cause locally or generally darker (hyperpigmentation) or lighter (hypopigmentation) skin.
- Even though the skin lesions are usually asymptomatic, they may affect the patient's quality of life significantly (cosmetic disturbance and psychosocial problems).
- Drugs and certain systemic diseases may cause generalized or local changes of skin colour.
Pathogenesis
- Changes in skin colour are usually due to increased or decreased amounts of melanin pigment and/or of melanocytes (hyperpigmentation or hypopigmentation, respectively).
- Chronic abrasion may lead to thickening of the epidermis, causing visible hyperpigmentation (e.g. calluses, mechanical abrasion, neurodermatitis).
- In generalized pigmentary disorders the cause may be hormonal (e.g. melanocyte stimulation caused by high levels of melanocyte-stimulating hormone [MSH] in patients with hypocortisolism, or melasma during pregnancy).
- Skin colour may also change due to metabolic products accumulating in the skin (such as bilirubin in patients with jaundice or iron in patients with haemochromatosis).
Diagnosis
- The diagnosis is usually based on the patient history and clinical picture.
- What colour are the skin lesions? Is the pigmentary disorder local or generalized? How have the skin lesions developed? Does their location change?
- Does the patient have any history of diagnosed skin disorders, such as vitiligo or atopic eczema?
- Has the patient developed skin reactions in association with sun exposure? Are the locations typical for photodermatitis (face, neck, chest, arms)?
- Is it an acquired or a congenital disorder? Is there any family history of pigmentary disorders?
- Hormonal changes, oral contraceptives or pregnancy
- Oral medication or topical skin treatment, including natural drugs and treatments, sunscreen ointments and cosmetics
- Examine the whole skin and mucosa, including the palms and soles of the feet.
Localized darkening of the skin (hyperpigmentation)
Most common causes
- Pityriasis versicolor Pityriasis Versicolor
- Reddish brown, slightly scaly patches
- Most often on the upper trunk, neck and proximal parts of the limbs
- N.B.: Hypopigmentation may also occur (see below)
- Melasma (Image 1)
- Clearly defined, light brown, hyperpigmented patches
- In areas of the skin exposed to the sun, usually the face
- May appear during pregnancy or after using hormonal contraception.
- Postinflammatory hyperpigmentation: when healing, many skin disorders may leave slowly fading dark patches; eczemas, psoriasis Psoriasis, purpura Easy Bruising, Petechiae and Ecchymoses, lichen ruber planus Lichen Planus, for instance.
- Physiological changes in pigmentation during pregnancy Skin Problems during Pregnancy
- Café au lait spots
- Clearly defined light brown patches on the trunk or the limbs (Image 2)
- Single patches are quite common; numerous patches in a child or adolescent may suggest neurofibromatosis.
Less common causes
- Diabetic dermopathy: clearly defined light brown patches on both legs
- Acanthosis nigricans (Images 3 4)
- Dark discolouration of armpits and groin
- May cause warty thickening of the skin.
- May be idiopathic but is usually due to obesity or type 2 diabetes.
- When occurring as a new symptom in an adult may represent a paraneoplastic phenomenon.
- Allergic contact eczema (Riehl melanosis) Allergic Contact Dermatitis
- In areas of skin exposed to sun allergic contact eczema may cause patchy hyperpigmentation.
- This usually represents contact allergy to cosmetic ingredients (such as perfumes or preservatives).
- Photocontact dermatitis (Berloque dermatitis) Photodermatitis
- May be caused by perfumes, sunscreen chemicals, analgesic gels or ointments.
- In addition, some plants may cause what is called phytophotodermatitis.
- Drug-induced photodermatitis Photodermatitis: diffuse hyperpigmentation may develop in light-exposed areas after eczema.
- Fixed drug eruption (erythema fixum; Image 5)
- Appears always in the same place after drug intake.
- May leave a slowly fading dark patch on healing.
- Becker's naevus
- Usually appears in childhood but may become darker in teen years or early adulthood.
- Most commonly occurs in the shoulder or flank area.
- Poikiloderma of Civatte (Image 6)
- Reddish brown, reticular hyperpigmentation, skin atrophy and telangiectasia on the cheeks and neck
- In adults and elderly people
- Cause unclear; considered to be due to chronic photodamage.
- Erythromelanosis follicularis faciei
- Reddish brown, patchy hyperpigmentation, telangiectasia and follicular papules on both cheeks and temples and below the eyes
- In adolescence or early adulthood; more common in men
- Probably hereditary
- Erythema dyschromicum perstans (ashy dermatosis)
- Oval or round greyish brown hyperpigmented patches appear on the trunk, more rarely on the limbs or the face.
- Cause unclear
- Has a chronic course
Localized lightening of the skin (hypopigmentation)
Most common causes
- Pityriasis versicolor Pityriasis Versicolor
- May also cause light, slightly scaly patches on the skin.
- Vitiligo Vitiligo
- Asymptomatic, clearly defined white patches usually symmetrically on the limbs, on the trunk, in the navel area and on the nipples, on the face around the mouth and eyes
- Postinflammatory hypopigmentation: when healing, many skin disorders, such as psoriasis and atopic eczema, may leave slowly fading, white patches.
- Pityriasis alba
- Slightly scaly, white patches predominantly on the face and upper limbs
- Cause unknown; it may represent postinflammatory hypopigmentation and be associated with atopic eczema.
- Has a chronic course
Less common causes
- Depigmented naevi (halo naevi): a white, annular patch develops around a naevus.
- Idiopathic guttate hypomelanosis
- Small white patches on the limbs in photodamaged skin in the elderly
- Clinical picture resembling confetti
- Some topical drugs may cause white patches (retinoids, benzoyl peroxide and azelaic acid used for the treatment of acne, and topical and injectable glucocorticoids, for instance).
- Progressive macular hypomelanosis
- Asymptomatic white patches on the trunk, neck and proximal limbs, often merging in the midline
- Usually in people with dark skin
- Cause unclear
- Piebaldism
- Pigmentary disorder with autosomal dominant inheritance
- White patches, most commonly on the scalp or facial area from birth
- Hair or eyebrows grow white in the affected areas (poliosis).
- May also occur on the trunk and limbs.
- The location of the lesions does not change.
- White patches in patients with tuberous sclerosis: white (ash-leaf) spots from birth on the trunk and limbs; additionally facial fibromas and epilepsy
- Leprosy (tuberculoid leprosy) Bacterial Diseases in Warm Climates
- White patches predominantly on the limbs, with reduced skin sensation and reduced sweating
- May occur in immigrants
Generalized (diffuse) pigmentary disorders
- Usually diffuse, symmetric changes in skin colour.
- If there is an underlying systemic disease, the pigmentary disorder appears as a new symptom in a patient with other findings, as well.
Hyperpigmentation
- Drug-induced diffuse hyperpigmentation
- Most commonly caused by antimalarial drugs, hydroxychloroquine, amiodarone, minocycline, anticancer drugs, chlorpromazine, tricyclic antidepressants or antiepileptic drugs
- Addison's disease Addison's Disease and other Conditions Inducing Hypocortisolism
- Diffuse darkening of the skin, particularly in the creases on the palms and on the soles of the feet
- Gingival and oral mucosal hyperpigmentation as a new symptom
- Vitamin B12 deficiency Megaloblastic Anaemia
- Diffuse darkening of the skin and Addison's disease-like clinical symptoms and findings
- Other symptoms include anaemia, neurological symptoms and atrophic glossitis
- Acromegaly due to a pituitary tumour Pituitary Tumours and Cushing's syndrome Cushing's Syndrome: diffuse darkening of the skin due to melanocyte-stimulating hormone (MSH) secretion
- Haemochromatosis Haemochromatosis
- Diffuse bronze or slate grey darkening of the skin, 'bronze diabetes'
- Predominantly on areas exposed to light: the face, neck, upper limbs
- Patchy hyperpigmentation of the mucosa
- Porphyria cutanea tarda Porphyrias (Image 7)
- Melasma-type patchy hyperpigmentation of the face
- Chronic renal failure Treatment of Chronic Renal Failure
- Diffuse yellowish brown hyperpigmentation of the skin
- Liver disorders (cirrhosis of the liver Cirrhosis of the Liver, liver cancer and metastases, primary biliary cholangitis Primary Biliary Cholangitis)
Hypopigmentation
- Hypothyroidism Hypothyroidism
- The skin may be pale, dry and scaly.
- Pituitary failure (hypopituitarism Pituitary Tumours)
- Diffuse lightening of the skin
- Albinism, other genetic syndromes and metabolic disorders: diffuse hypopigmentation usually since birth
Jaundice
- Jaundice A Patient with Jaundice (Icterus)
- Cholestasis, liver disorders and liver metastases may cause also diffuse yellowish brown darkening of the skin.
- Hypercarotenaemia
- Excessive intake of carrots or other food or natural products containing carotenes
- Diabetes, liver or kidney disease, hypothyroidism
- Elastosis (Image 8)
- Chronic exposure to sunlight, particularly on the face of elderly people
- Deep furrows and yellowish skin tone
Workup
- Further tests are rarely needed; the clinical picture is decisive.
- In pityriasis versicolor and seborrhoeic eczema, Malassezia yeast may be seen on microscopy (native fungal examination) but fungal culture may still be negative. The diagnosis is based on clinical features.
- Histological examination of a skin biopsy specimen may be helpful if a specific skin disorder is suspected. The biopsy specimen should be taken at an active stage of the disease.
- Epicutaneous and/or photopatch tests may be indicated if allergic contact dermatitis is suspected.
- If a pigmentary disorder due to an internal disease is suspected, targeted, stepped laboratory tests should be performed, as necessary.
Treatment
Hyperpigmentation
- Treatment of pityriasis versicolor Pityriasis Versicolor
- Sun protection and use of a suitable sunscreen ointment often help.
- Causal treatment (visceral diseases; avoidance of causative factor in allergic contact dermatitis, photodermatitis, drug-induced pigmentary disorders)
- In the case of postinflammatory pigmentary disorders, treatment of the causative skin disease. The response for the actual pigmentary disorder is often poor but the skin tone often evens out within 6-12 months.
- For local hyperpigmentation (melasma, postinflammatory hyperpigmentation) there is evidence of the efficacy of (2-4%) hydroquinone ointments Interventions for Melasma. Hydroquinone may require special permit.
- In Finland, hydroquinone can no longer be prescribed for extemporaneous compounding. A hydroquinone-containing combination cream (Pigmanorm®) is available with special permit for compassionate use. A thin layer of the ointment is applied once daily, at night, in courses of 1-3 months until the skin area becomes lighter.
- There is also some evidence for the efficacy of topical treatment with azelaic acid or retinoids (e.g. 0.025% or 0.05% tretinoin ointment).
- For example, once daily, at night, in courses of 1-3 months, depending on response
- In severe cases, topical treatment has been combined with glycolic acid peeling and laser treatments (possibly available through private health care only).
Hypopigmentation
- Treatment of pityriasis versicolor Pityriasis Versicolor
- Treatment of vitiligo Vitiligo
- For hypopigmentation of other causes, there are no evidence-based treatments available.
- Covering treatment and makeup
Specialist consultation
- For severe pigmentary disorders or ones causing significant psychosocial suffering, consultation of a dermatologist should be considered.
References
- Rivas S, Pandya AG. Treatment of melasma with topical agents, peels and lasers: an evidence-based review. Am J Clin Dermatol 2013;14(5):359-76. [PubMed]
- Rajaratnam R, Halpern J, Salim A et al. Interventions for melasma. Cochrane Database Syst Rev 2010;(7):CD003583. [PubMed]
- Jutley GS, Rajaratnam R, Halpern J et al. Systematic review of randomized controlled trials on interventions for melasma: an abridged Cochrane review. J Am Acad Dermatol 2014;70(2):369-73. [PubMed]
- Kang HY, Valerio L, Bahadoran P et al. The role of topical retinoids in the treatment of pigmentary disorders: an evidence-based review. Am J Clin Dermatol 2009;10(4):251-60. [PubMed]
- Whitton M, Pinart M, Batchelor JM et al. Evidence-based management of vitiligo: summary of a Cochrane systematic review. Br J Dermatol 2016;174(5):962-9. [PubMed]
- Hu SW, Bigby M. Pityriasis versicolor: a systematic review of interventions. Arch Dermatol 2010;146(10):1132-40. [PubMed]
- Ezzedine K, Whitton M, Pinart M. Interventions for Vitiligo. JAMA 2016;316(16):1708-1709. [PubMed]