A – Z of Skin

Information for Skin, Hair and Nail Conditions

WHAT IS THE A-Z OF SKIN?

The A to Z of Skin information has been developed to help you understand more about common skin conditions and problems, and how these may be treated.

Both common and medical names have been included to help your search, as well as the names of medications and treatments. There are also a number of cosmetic topics which explain the latest treatments for cosmetic concerns related to the skin. Many College dermatologists have contributed to the information on this site.

The process has been overseen by a committee of dermatologists to ensure that the final versions are both accurate and user friendly. Particular thanks go to Dr Pam Brown, Dr Peter Berger, Dr Davin Lim, Dr Michelle Rodrigues, Dr Yin Vun, Conjoint Associate Prof Orli Wargon and Dr Eleni Yiasemides (Chair). The A to Z information is currently under development. Please check back on a regular basis for updates and the addition of new topics.

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  • Palmar hyperhidrosis

    Palmar hyperhidrosis, or excessive hand sweating, is a common condition affecting 1-3% of the population. It usually starts in childhood or adolescence. Sweaty hands can significantly affect a person socially and emotionally.

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  • Palmoplantar keratoderma

    Palmoplantar keratoderma is the name given to a group of conditions where there is abnormal thickening of the skin on the palms of the hands and soles of the feet.

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  • Palmoplantar pustulosis

    Palmoplantar pustulosis (PPP) is a chronic pustular condition affecting the palms of the hands and/or soles of the feet. It may occur with psoriasis or without any other skin disease.

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  • Palpable migrating erythema

    Palpable migrating erythema also known as erythema annulare centrifugum (EAC), refers to an annular (ring-shaped) erythematous (red) skin eruption that tends to spread outwards whilst clearing centrally.

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  • Panniculitis

    Panniculitis refers to a group of conditions characterised by inflammation of the fat layer below the skin (sub-cutaneous fat). It can be localised to a particular part of the body or involve larger areas.

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  • Papular acrodermatitis of childhood

    Papular acrodermatitis of childhood also known as Gianotti-Crosti syndrome is the name given to a rash which is caused by a viral infection. It is typically found on the legs, buttocks, arms and face of children aged 6 months to 14 years. The condition usually clears spontaneously and without treatment over a period of 12 weeks.

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  • Papular dermatoses of pregnancy

    Papular dermatoses of pregnancy is also known as atopic eruption of pregnancy. This is the most common of the pregnancy dermatoses (incidence 1:300-3000).

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  • Papular urticaria

    Papular urticaria is a term used to describe hypersensitivity or an allergic reaction to insect bites manifested by recurrent and persistent itchy lumps or fluid filled blisters.

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  • Paraneoplastic pemphigus

    Paraneoplastic pemphigus is a rare, severe blistering condition of the mucosal surfaces and skin associated with an underlying cancer.

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  • Parvovirus B19 infection

    Parvovirus B19 infection also known as erythema infectiosum, is usually a harmless childhood viral infection characterised by a classic slapped-cheek appearance or a lacy patterned rash. The infection can be associated with fevers.

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  • Pearly penile papules

    Pearly penile papules are very small skin coloured lesions on the end part of the penis (glans)

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  • Pediculosis

    Pediculosis is the medical term for an infection or infestation with lice which are blood feeding parasites.

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  • Pemphigoid gestationis (PG)

    Pemphigoid gestationis (PG) is a relatively rare pregnancy dermatosis characterised by blisters

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  • Pemphigus foliaceus

    Pemphigus foliaceus is a rare autoimmune blistering disease which is characterised by superficial blisters, erosions and crusts on the skin.

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  • Pemphigus vulgaris

    Pemphigus vulgaris is a rare autoimmune blistering disease which is characterised by blisters, erosions and crusts in the mouth and on the skin.

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  • Periadenitis mucosa necrotica recurrens (PMNR)

    Periadenitis mucosa necrotica recurrens (PMNR) also known as Aphthous ulcers, are a common problem with a higher prevalence in high socio-economic areas.

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  • Perioral dermatitis

    Perioral dermatitis is a common inflammatory rash that occurs around the mouth area. Other affected areas include around the nose, chin and eyes.

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  • Periorificial dermatitis

    Periorificial dermatitis also known as perioral dermatitis is a common inflammatory rash that occurs around the mouth area. Other affected areas include around the nose, chin and eyes.

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  • Perlèche

    Perlèche also known as angular cheilitis, is an inflammation of the corners of the mouth, often bilateral (it often affects both corners of the mouth). The condition presents with redness and irritation.

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  • Perniosis

    Perniosis also known as chilblains, are itchy, red swollen tender areas of skin that develop on the exposed skin of fingers, toes or rims of ears after exposure to cold at temperatures above O° Celsius.

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  • Persistent palmoplantar pustulosis

    Persistent palmoplantar pustulosis also known as palmoplantar pustulosis (PPP), is a chronic pustular condition affecting the palms of the hands and/or soles of the feet. It may occur with psoriasis or without any other skin disease.

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  • Photodynamic therapy

    Photodynamic therapy is a treatment for various skin conditions. It requires a combination of a medication and the application of energy to create a chemical reaction that targets certain growths or skin conditions. The medication is applied usually in a cream formulation and the energy is obtained from a strong light source.

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  • Phototherapy

    Phototherapy uses different wavelengths of ultraviolet light to treat widespread skin diseases that cause inflammation (redness, scaling, itching, tenderness and swelling) in the surface and deeper layers of the skin, as well as conditions that cause loss of colour.

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  • Pigmentation of Pregnancy

    Pigmentation of pregnancy also known as Melasma appears as patchy shades of brown pigmentation on sun exposed areas of the face.

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  • Pigmented purpuric dermatosis

    Pigmented purpuric dermatosis is an uncommon condition that affects all races and ages. It usually manifests as small or large patches of cayenne pepper coloured spots and pigmentation. The skin rash is usually found on the lower limbs but may also involve the trunk.

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  • Pimples

    Pimples also known as acne is a very common skin condition that usually begins in adolescence. The hair follicle and its associated oil (sebaceous) gland become blocked and inflamed.

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  • Pityriasis Alba

    Pityriasis alba is a benign and very common, self-resolving, eczematous (mild dermatitis) rash that most commonly affects children and young adults. It is more noticeable in people with skin of colour (pigmented skin).  

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  • Pityriasis rosea

    Pityriasis rosea is a common self-resolving rash that usually occurs in children and young adults but can occur at any age. Individuals are generally otherwise well.

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  • Pityriasis Rubra Pilaris

    Pityriasis Rubra Pilaris is a rare scaly red/orange rash which is mildly itchy and can progress to cover most of the body. The cause of pityriasis rubra pilaris is unknown. It is not infectious.

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  • Pityriasis versicolor

    Pityriasis versicolor is a common skin rash in puberty and early adult life but can occur in infants. It is more common in warm humid environments and may be seasonal. Most people with this condition are concerned about the appearance of the rash. Sometimes it may cause minor symptoms such as scaling, itch or irritation. It can be much more widespread if there is a problem with the immune system.

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  • Plantar hyperhidrosis

    Plantar hyperhidrosis is a common condition affecting 1-3% of the population. The condition usually starts in childhood or adolescence.  It can cause significant physical limitations and predispose to bacterial and fungal infections and friction blisters.

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  • Plumber’s itch

    Plumber’s itch also known as cutaneous larva migrans, is an itchy localised skin infestation caused by the penetration and migration of animal hookworm larvae through the skin.

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  • Poikiloderma of Civatte

    Poikiloderma of civatte was first described in 1923 and refers to redness and mottled pigment on the sides of the neck. The area under the chin is usually unaffected.

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  • Polymorphic eruption of pregnancy

    Polymorphic eruption of pregnancy (PEP) is a relatively common pregnancy dermatosis that causes very itchy red bumps to appear over the abdomen.

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  • Polymorphic light eruption

    Polymorphic light eruption is a sunlight-sensitive rash (photodermatosis) on skin that has been exposed to sunlight. As the name “polymorphic” suggests, the rash can present in many different forms from tiny red pin-head sized spots through to large patches of redness.

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  • Polymorphous light eruption

    Polymorphous light eruption also known as Polymorphic light eruption is a sunlight-sensitive rash (photodermatosis) on skin that has been exposed to sunlight. As the name “polymorphic” suggests, the rash can present in many different forms from tiny red pin-head sized spots through to large patches of redness.

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  • Pompholyx

    Pompholyx is an often recurrent and frequently extremely itchy disorder characterised by tiny blisters and bumps on the sides of fingers, toes, palms and soles.

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  • Porphyria cutanea tarda

    Porphyria cutanea tarda (PCT) is a rare condition which is characterised by blistering and fragility of the skin in sun exposed areas.

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  • Port-wine stain

    A port-wine stain is a pink to red flat patch on the skin which has well-defined edges.  It is a true birthmark present in 3 to 5 per 1000 newborn babies. It is permanent and its area will increase in proportion to general body growth.

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  • Post endoscopic thoracic sympathectomy (ETS) sweating

    Post endoscopic thoracic sympathectomy (ETS) sweating also known as compensatory hyperhidrosis, is a common post-surgical complication of endoscopic thoracic sympathectomy (ETS surgery).

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  • Post-adolescent acne

    Post-adolescent acne also known as adult acne, is acne that continues past the ages of 18 to 20 or starts in the early 20s in individuals who may not have had a previous problem with acne.

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  • Post-inflammatory hyperpigmentation

    Damage to the skin from trauma or inflammation may result in discolouration of the affected area.  Compared with normal skin, these areas may appear slightly darker in colour (hyperpigmentation).

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  • Post-inflammatory hypopigmentation

    Damage to the skin from trauma or inflammation may result in discolouration of the affected area.  Compared with normal skin, these areas may appear slightly lighter (hypopigmentation).

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  • Post-Inflammatory Pigmentation

    Damage to the skin from trauma or inflammation may result in discolouration of the affected area. Compared with normal skin, these areas may appear slightly darker in colour (hyperpigmentation) or slightly lighter (hypopigmentation).

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  • Pregnancy dermatoses

    Pregnancy dermatoses are rashes that only occur in pregnancy. There are four main conditions: Atopic eruption of pregnancy; Polymorphic eruption of pregnancy; Pemphigoid gestationis; Intrahepatic cholestasis of pregnancy.

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  • Prickly heat

    Prickly heat also known as miliaria, is a group of skin conditions that arise from blockage of sweat ducts.

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  • Primary Cutaneous B-Cell Lymphoma (PCBCL)

    Tumours of the lymph nodes and lymphatic system are called “lymphomas”. B-cell lymphomas are caused by an excess of B-cell lymphocytes, a type of white blood cell.

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  • Primary neuroendocrine carcinoma of the skin

    Primary neuroendocrine carcinoma of the skin also known as merkel cell carcinoma, is a very uncommon type of aggressive skin cancer.  It presents most commonly in elderly fair-skinned individuals, particularly in sun-exposed areas on the head, neck and limbs.

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  • prurigo gravidarum

    Prurigo gravidarum also known as Intrahepatic cholestasis of pregnancy, is a rare liver condition which causes an itchy skin. There is no rash but the skin may show scratch marks (excoriations) or become yellow (jaundiced).

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  • Prurigo nodularis

    Prurigo nodularis is an intensely itchy, abraded (severely scratched-looking) rash characterised by discreet, thickened and leathery nodules or bumps. The condition usually occurs on the outer surfaces of the arms and legs. It is considered to be a localised form of lichen simplex chronicus which is a chronic condition characterised by itchy and thickened skin.

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  • Prurigo of pregnancy

    Prurigo of pregnancy is also known as atopic eruption of pregnancy. This is the most common of the pregnancy dermatoses (incidence 1:300-3000).

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  • Pruritic folliculitis of pregnancy

    Pruritic folliculitis of pregnancy is also known as atopic eruption of pregnancy. This is the most common of the pregnancy dermatoses (incidence 1:300-3000).

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  • Pruritic urticarial papules and plaques of pregnancy (PUPPP)

    Pruritic urticarial papules and plaques of pregnancy also known as polymorphic eruption of pregnancy, is a relatively common pregnancy dermatosis that causes very itchy red bumps to appear over the abdomen.

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  • Pruritus ani

    The term "pruritus ani" refers to an 'itchy bottom'. This is a common and distressing problem for many people. It occurs most commonly in middle-aged white men. There are many simple things that can be done to help ease the symptoms. However, treatment may not completely cure the problem.

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  • Pruritus with no rash

    Pruritus means itch. Itching is a very common symptom of skin conditions such as eczema, scabies, insect bites and hives. These skin conditions are characterised by the presence of a rash.

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  • Pseudofolliculitis barbae

    Pseudofolliculitis barbae is a chronic inflammation of hair-bearing areas of the skin caused by ingrown hairs that develop after shaving or plucking.

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  • Pseudopelade in African Americans

    Pseudopelade in African Americans also known as Central centrifugal cicatricial alopecia (CCCA) is a chronic and progressive type of scarring alopecia that results in permanent hair loss. CCCA most commonly starts in the centre of the scalp and, without treatment, expands over time causing an irreversible area of baldness. It is most commonly seen in middle-aged African women.

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  • Pseudopelade of the Central Scalp

    Pseudopelade of the central scalp also known as Central centrifugal cicatricial alopecia (CCCA) is a chronic and progressive type of scarring alopecia that results in permanent hair loss. CCCA most commonly starts in the centre of the scalp and, without treatment, expands over time causing an irreversible area of baldness. It is most commonly seen in middle-aged African women.

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  • Psoriasis

    Psoriasis is a lifelong skin condition characterised by the development of red scaly areas of skin. About 50% of people affected with psoriasis have changes to their nails and about 25% of people have pain, swelling and tenderness of their joints.

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  • Pustular eruption

    Pustular eruption also known as Acute generalised exanthematous pustulosis (AGEP) is a rare skin condition triggered predominantly by medications (incidence 3 to 5:1,000,000 per year), mainly in adults. AGEP is rarely fatal.

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  • Pustulosis palmaris et plantaris

    Pustulosis palmaris et plantaris also known as palmoplantar pustulosis (PPP), is a chronic pustular condition affecting the palms of the hands and/or soles of the feet. It may occur with psoriasis or without any other skin disease.

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  • Pyoderma gangrenosum

    Pyoderma gangrenosum is a rare cause of chronic, recurrent and painful non-infectious skin ulcers. It is classified as a neutrophilic dermatosis (skin disorder that has dense infiltration of inflammatory cells called neutrophils).

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  • Pyogenic Granuloma

    A pyogenic granuloma is a common benign (not malignant) growth of blood vessels on the skin. It appears as a single fast growing red nodule that commonly bleeds. Whilst benign, pyogenic granulomas can be distressing due to their appearance and fast growth.

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