Introduction
The colour of skin and hair is mainly due to the amount of brown melanin pigment mixed with blue (from reduced haemoglobin), red (from oxyhaemoglobin) and yellow (from carotenoids in the diet). The amount of melanin is determined by constitutional colour (white, brown or black skin) and skin phototype.
Increase in melanin (hyperpigmentation, hypermelanosis) can be due to an increased number of pigment cells (melanocytes) or from increased production of melanin.
Reduction in melanin results in pale patches (hypopigmentation, hypomelanosis). White skin or white patches (depigmentation, leukoderma) are due to an absence of melanocytes or loss of melanin in the epidermis. See DermNet's article on pigmentation disorders for more details.
Generally dark skin
- Acromegaly
- Addison disease
- Drug-induced pigmentation (phenothiazines, silver, chemotherapy)
- Haemochromatosis
- Ichthyosis
- Sézary syndrome
- Porphyria cutanea tarda
- Systemic sclerosis
- Wilson disease
Darker skin patches
- Acanthosis nigricans
- Acquired dermal macular hyperpigmentation
- Alkaptonuria
- Becker naevus
- Berloque dermatitis
- Confluent and reticulated papillomatosis
- Congenital naevi
- Dark circles under the eyes
- Diffuse melanosis cutis
- Dowling-Degos disease
- Fixed drug eruption
- Erythema ab igne
- Erythrasma
- Flagellate erythema
- Freckles, lentigines
- Gastrointestinal stromal tumour (GIST) — cutaneous hyperpigmentation disease associated with mastocytosis and c-kit mutation
- Idiopathic eruptive macular hyperpigmentation
- Laugier-Hunziker syndrome
- Lichen planus pigmentosa
- Lipodermatosclerosis
- Maculopapular cutaneous mastocytosis
- Melanoma
- Melasma
- Moles
- Mongolian spot
- Morphoea (morphea)
- Naevi of Ota and Ito
- Neurofibromatosis
- Ochronosis
- Pigmented contact cheilitis
- Pigmented purpura
- Pityriasis versicolor (tinea versicolor)
- Poikiloderma of Civatte
- Postinflammatory (trauma, burns, skin disease)
- Prurigo pigmentosa
- Purpura
- Segmental pigmentation disorder
- Systemic sclerosis
- Terra firma-forme dermatosis
- Tinea nigra
- Urticaria pigmentosa
Pale or white skin/patches
- Albinism
- Atrophie blanche
- Bleaching creams
- Contact leukoderma
- Degos disease
- Griscelli syndrome
- Halo moles
- Hermansky-Pudlak syndrome
- Hypomelanosis of Ito
- Idiopathic guttate hypomelanosis
- Leprosy
- Leukoderma
- Lichen sclerosus
- Lupus erythematosus
- Topical medications including topical retinoids, topical steroids, benzoyl peroxide, azelaic acid, hydroquinone
- Morphoea
- Mycosis fungoides
- Naevus anaemicus
- Naevus depigmentosus
- Piebaldism
- Pityriasis alba
- Pityriasis versicolor
- Poliosis
- Postinflammatory hypopigmentation (trauma, burns, skin disease especially atopic eczema, seborrhoeic dermatitis, discoid eczema, contact dermatitis, psoriasis, pityriasis rosea)
- Progressive macular hypopigmentation
- Sarcoidosis
- Segmental pigmentation disorder
- Systemic sclerosis
- Tinea corporis
- Tuberous sclerosis (ashleaf spots)
- Vitiligo
- Waardenburg syndrome