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Acanthosis nigricans | Acne vulgaris | Acrochordons | Actinic cheilitis | Actinic keratoses | Actinic lentigines | Age Spots (go to actinic lentigines) | Ageing skin | Albinism | Allergy | Alopecia | Alopecia areata | Anaphylaxis | Androgenetic alopecia | Angioedema | Angiokeratomas | Angular cheilitis | Annular erythema | Aphthous ulcers | Aplasia cutis | Athlete's foot (see tinea pedis) | Atopic dermatitis | Atopic eczema (go to atopic dermatitis) | Atrophie blanche

ACANTHOSIS NIGRICANS

This is a skin condition that causes a dark velvety thickening of the skin on the neck, armpits and groin.

    Causes

  • Endocrine of hormonal abnormality.
  • Inherited disorder.
  • Drug induced eg., from nicotinic acid, oral contraceptives and stilboestrol.
  • Obesity when it is called pseudoacanthosis nigricans.
  • Underlying cancer.

    Symptoms

  • Thick, grey or black velvety skin on the neck, groin or armpits.
  • In acanthosis nigricans due to underlying cancer, there may be velvety thickening inside the mouth, as well.
     
    Acanthosis nigricans affecting the armpit in a patient with underlying cancer.
    Click on image for larger view.
    What you can do
  • You chould consult a doctor to determine the cause.
  • Weight reduction may improve pseudoacanthosis nigricans.

    What the doctor may do

  • Determine the cause.
  • Treat the underlying cause.

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ACNE VULGARIS

Acne vulgaris or acne is the medical term for pimples. It usually begins in puberty in both sexes when the adrenal glands (which sit on top of the kidneys) and sex organs start producing androgens (male hormones).

Acne is most common between the ages of 16 - 18 and becomes less common thereafter. However, about 1 in 5 adults, especially women continue to be troubled by acne, although it is usually less severe.

Acne usually affects the face and occasionally, the neck, chest, shoulders and back, as well. Treatment is not a cure but it can the problem and reduce the risk of permanent scars.

    Causes
    The exact cause is unknown but the following factors may play a role:

  • Increased sebum (skin oil) production by the sebaceous glands (skin's oil-glands) under the influence of androgens.
  • Blockage of the hair follicles (skin pores), resulting in comedones (whiteheads and blackheads).
  • Proliferation of Propionibacterium acnes (the acne bacteria) which converts sebum into irritating fatty acids.
  • Inflammation caused by the seepage or release of irritating fatty acids into the dermis, resulting in red papules (red pimples) or pustules ("pusheads") and in some patients, nodules (deep and sometimes painful swellings that look like boils).

    Aggravating factors

  • Family history of severe acne.
  • Stress.
  • Hot, humid environment.
  • Occupational due to exposure to acne causing chemicals such as mineral oil and halogenated aromatic hydrocarbons, including dioxin. The latter causes chloracne.
  • Pre-menstruation.
  • Cosmetics such as moisturisers containing acne causing ingredients such as isopropyl myristate, lanolin, sodium lauryl sulfate, laureth-4, butyl stearate, lauryl alcohol, oleic acid, petroleum oils).
  • Friction from headbands and chin straps.
  • Medications such as lithium (used to treat manic-depressive states), phenytoin (used to treat epilepsy or fits), iodides, anti-tuberculous drugs (ethionamide, rifampicin, isoniazid), B vitamins and cyclosporin (used to prevent the rejection of transplanted organs), systemic steroids, testosterone and anabolic steroids (sometimes abused by athletes and body-builders).
  • Polycystic ovaries which produce androgens (male sex hormones).
  • Excessive production of corticosteroids (Cushing's syndrome).

    Key Points

  • Acne is not caused by uncleanliness, unfulfilled sexual desires or "dirty blood".
  • Acne is not caused by fatty foods or chocolates.
  • Acne gets better eventually or "burns itself out" even without treatment but the scars that result from neglected acne are permanent.
  • Early treatment is advised, especially if the parents have a history of severe acne.
  • There is no quick cure for acne but treatment can control acne and help to prevent severe and permanent scarring.
  • Treatment is often prolonged, spanning many months or even years and relapses are common, requiring retreatment.
  • There is no definite evidence that dietary items cause or flare-up acne. However, there is no harm in avoiding those substances suspected of doing so temporarily to see if there is any change.

    Symptoms

  • Comedones - open comedones (blackheads) and closed closed comedones (whiteheads).
  • Red papules (red bumps or pimples).
  • Pustules (pusheads).
  • Nodules (large swellings that may be painful and look like boils).
  • Cysts (fluid-filled swellings).
  • Seborrhoea (increased oiliness) is frequently present.
  • In a severe type of acne known as acne conglobata, there are multiple nodules, cysts and abscesses. Acne fulminans is even more severe. It looks like acne conglobata but is associated with fever and joint pains.
     

     

     

    Moderately severe acne showng inflamed papules.
    Click on image for larger view.

     

     

     

    Cyst near the eye.
    Click on image for larger view.

     
    Complications
  • Colour changes - postinflammatory erythema (red blotches), postinflammatory hyperpigmentation (dark blotches) and postinflammatory hypopigmentation (lightened blotches). These are temporary.
  • Scarring - depressed pock-like scars, pitted scars, ice pick scars and keloids. Scars are permanent but can be improved with treatment.
  • Loss of self-esteem

    What you can do

  • You should consult a doctor if you have severe acme or want faster results.
  • Clean with a medicated cleanser/soap.
  • Apply topical keratolytics (peeling agents) containing benzoyl peroxide, sulphur or salicylic acid.
  • See a doctor if these measures don't help or if the acne is very severe and is causing scarring.
  • Do not pick or squeeze acne as this causes more inflammation and increases the risk of scarring.
  • Emotional stress can worsen acne. Learn to cope with stress.
  • Some drugs can make acne worse. Check with your doctor.
  • Many cosmetic ingredients can cause acne so switch products if you notice more acne appearing.
  • Avoid using moisturisers routinely. If you must, use only water-based moisturisers and check that the label says "non-comedogenic" or "non-acnegenic". Preferably, they should not contain the acne-causing ingredients above.
  • The use of make-up is permissable if they are water-based or oil-free and non-comedogenic.

    What the doctor may do

  • Counsel you about acne.
  • Perform blood tests if there is evidence of excessive hormones and pelvic ultrasound if he suspects polycystic ovaries.
  • Prescribe topical (applied) or oral (taken by mouth) antibiotics, topical tretinoin (vitamin A acid), oral isotretinoin (another vitamin A acid), oral antiandrogens (used only in women only).
  • Inject intralesional steroids into nodules, cysts and keloids (lumpy scars).
  • Perform surgery to drain cysts (rarely necessary nowadays with new and more effective medication) or to improve scars.
  • Perform chemical peels and laser resurfacing to improve acne scars.

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ACROCHORDONS

Acrochordon (papilloma) is the medical term for a skin tag. This is a harmless skin growth, commonly seen in middle-aged adults.

    Causes
    Uncertain but the following factors appear to influence it's development:-
  • Familial tendency.
  • Obesity.

    Symptoms

  • Small fleshy skin-coloured tags.
  • Occur on areas subjected to friction such as the neck, armpits, groins and under the breasts and occasionally, on the eyelids as well.
  • They may increase in numbers during pregnancy.
     

    Acrochordons (skin tags) on the neck.
    Click on image for larger view.
    Complications
  • Torsion (twisting on itself) causing inflammation and pain.

    What you can do

  • You can consult a doctor for removal.
  • Do nothing since skin tags are cosmetic in nature.

    What the doctor may do

  • Remove them using surgical excision, electrosurgery, carbon dioxide laser or liquid nitrogen.

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ACTINIC CHEILITIS

This is a form of actinic keratosis affecting the lower lip. Like actinic keratoses, it is also more common among fair-skinned individuals, especially those of Celtic origin.

    Cause

  • Sun-damage.

    Symptoms

  • Redness, scaling, cracking and crusting of the lower lip.

    Complications

  • May develop into a squamous cell cancer.

    What you can do

  • You should consult a doctor.
  • Use sunscreen-containing lip balms or lip sticks.

    What the doctor may do

  • Perform a skin biopsy to confirm the diagnosis.
  • Counsel you about sun protection.
  • Excise (cut) or treat with the carbon dioxide laser or electrosurgery.

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ACTINIC KERATOSES

Actinic keratoses or solar keratoses are precancerous skin growths found on areas most exposed to the sun such as the face, ears, sides of the neck and back of the hands and forearms. The term actinic cheilitis is used when it affects the lower lip. Actinic keratoses are more common in the elderly because of years of exposure to the sun and in fair-skinned individuals, especially those of Celtic origin.

    Cause

  • Sun-damage.
     
    Symptoms
  • Red or yellow-brown, scaly patches which feel coarse like sandpaper.
  • Other signs of chronic sun damage such as solar elastosis, senile comedones (whiteheads and blackheads) and telangiectasias may be present.
  • Cutaneous horns are a variety of actinic keratoses. They project out of the skin rather like a small horn.
     
     
    Actinic keratosis on the scalp
    Click on image for larger view
    Complications
  • May develop into a squamous cell cancer.

    What you can do

  • You should consult a doctor.
  • Protect your skin against further sun-damage (see sun protection).

    What the doctor may do

  • Perform a skin biopsy to confirm the diagnosis.
  • Counsel about sun protection.
  • Treat with topical 5-fluorouracil, liquid nitrogen, electrosurgery and curettage (scraping), dermabrasion (skin planing), laser resurfacing or chemical peels.
  • Examine the skin carefully for skin cancers.
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ACTINIC LENTIGINES

Actinic lentigines, senile lentigines, solar lentigines, "liver spots" and "age spots" are different terms for the same condition. They occur on the sun-exposed skin of the middle-aged and elderly.

    Causes

  • Sun-damage.

    Symptoms

  • Light or dark brown blotches measuring 4 - 30 mm in size.
  • Affects the sun-exposed areas, especially the face, back of the hands, the forearms, upper back and chest.
  • Signs of chronic sun-damage such as telangiectasias, solar elastosis and coarse wrinkles are often present.
      Actinic lentigines.
    Click on image for larger view.
    What you can do
  • You can consult a doctor for remioval.
    Protect your skin against further sun-damage (see sun protection ).

    Caution
  • Lentigo maligna appears as a slowly growing flat dark patch with an irregular and indistinct border and various shades of brown, tan and black. It occurs most commonly on the face or neck of an elderly person and can develop into malignant melanoma.

    What the doctor may do

  • Perform a skin biopsy if the diagnosis of lentigo is uncertain or if there is a possibility of lentigo maligna.
  • Counsel about sun protection.
  • Remove or lighten for cosmetic reasons using a number of different methods:
     

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AGEING SKIN

Skin ageing may be divided into two types:

  • Intrinsic ageing which is genetically determined and
  • Photoageing (dermatoheliosis) which is caused by excessive exposure to the sun. Fair-skin individuals and those occupationally or recreational exposed to the sun are likely to develop photoageing early. Eighty per cent of the signs of ageing is believed to be caused by sun damage. Accordingly, the best way to delay ageing is to minimise exposure to the sun (see sun protection).

    Symptoms
    The symptoms depend on the site of damage:
     
  • Epidermis (superficial skin)
     
  • Melanocytes (pigment cells)
     
  • Connective tissue
      Coarse wrinkles due to photoageing.
    Click on image for larger view.
  • Sebaceous glands
     
  • Hair
     
  • Blood vessels
     
  • Subcutaneous fat
    • Fat atrophy leading to sunken cheeks, thinned skin.

    What you can do

    Obviously you cannot prevent ageing but the following measures may help:
     
  • Avoid sun-damage (see sun protection).
  • Get enough sleep and rest.
  • Exercise
  • Healthy diet.
  • Don't smoke.
  • Don't take too much alcohol.
  • Don't do drugs.

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ALBINISM

This is a rare inherited condition caused by the partial or total lack of melanin. The most common form of albinism is called oculocutaneous albinism. Partial albinism is much rarer and affects only the skin, the hair or the eyes. Ocular albinism affects the eyes alone.

    Causes

  • Inherited defect in the synthesis of the skin pigment, melanin. Oculocutaneous albinism and ocular albinism have different modes of inheritance - autosomal dominant, autosomal recessive or X-linked.

    Symptoms

  • In severely affected cases, the skin and hair are snowy white.
  • The iris (the area of the eyes surrounding the pupil) and the retina (back of the eyes) are white and the eyes cannot tolerate bright lights and are affected by nystagmus (abnormal jerky eye movements), squint and myopia (short-sightedness).
  • Ocular albinism affects the eyes alone.

    Complications

  • There is a high risk of skin cancer developing in oculocutaneous albinism because the skin lacks the melanin that shields off harmful ultraviolet rays.

    What you can do

  • You should consult a doctor.
  • Protection against the sun is very important because of the risk of skin cancer developing (see sun protection).

    What the doctor may do

  • Provide genetic counseling and advice on sun-protection.
  • Follow-up closely for the developing of skin cancers.

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ALLERGY

Allergy is an abnormal reaction to substances that are normally harmless or beneficial to the body.

    Cause
  • Normally, our bodies produce antibodies in response to attack by a potentially harmful foreign substance such as viruses and bacteria. In the case of an allergy, however, antibodies are produced against substances that are harmless or good for the body (for example, food items or a particular treatment). These antibodies combine with the substance (known medically as the allergen) and this sets off a chain of chemical reactions that lead to the release of histamine, the chemical that produces most of the symptoms of an allergy. The allergen may be a substance taken into the body such as a drug or food item, dust, venom from an insect bite (see bites and stings) or a substance that has been in contact with the skin such as costume jewelry, cosmetics or plants (see contact dermatitis). Theoretically, any substance can cause an allergy, including one the person has taken or been in contact with before without problems.

    Symptoms

  • Contact dermatitis - Eczema or itchy red scaly or weepy patches.
  • Urticaria (weals or nettle rash).
  • Morbilliform (measles like) rash.
  • Purpura.
  • Vasculitis.
  • Erythema multiforme.
  • Erythema nodosum.
  • Fixed drug eruption.

    Complications

  • Anaphylaxis - A severe reaction resulting in shock, suffocation and even death.

    What you can do

  • You should consult a doctor.
  • Take antihistamine to relieve itch.
  • Apply calamine lotion.
  • Go to the nearest Accident and Emergency Department if you have generalised urticaria or swelling of the eyelids, lips or difficulty breathing or if there are signs of anaphylaxis developing.

    What the doctor may do

  • Hospitalise severe cases of allergy.
  • Give antihistamine injections.
  • Prescribe systemic steroids.
  • Determine the cause of the allergy with the aid of patch tests, skin tests (prick or intradermal tests) or RAST tests if necessary.
  • Desensitise selected cases. This is done by injecting small doses of an allergen in order to train the body to accept it. However, desensitisation is only available for some allergens such as house dust, poison ivy and bee and wasp stings and there is a small risk of desensitisation causing a severe reaction.

    Prevention

  • Avoid the substances you are allergic to.
  • Apply for a medical alert (for example, Medik Awas) card and carry it on your person all the time. Get the application form from your doctor.
  • Inform your doctor, dentist, and pharmacist each time you see them.
  • Inform your relatives about your allergy, as well.

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ALOPECIA

Alopecia is the medical term for hairloss. Doctors divide alopecia into non-scarring and scarring alopecia. Scarring alopecia is due to inflammation causing scarring and destruction of the hair follicles. The causes include:

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ALOPECIA AREATA

Alopecia areata causes hairloss in round patches. It usually affects young adults and children and may be associated with a family history of alopecia areata or other autoimmune disorders (self-allergies) such as vitiligo and thyroid disease (Hashimoto's thyroiditis).

    Cause

  • Alopecia areata is believed to be an autoimmune disorder in which the body produces antibodies that attack the hair follicles as though they were foreign.

    Symptoms

  • Solitary or multiple well-defined circular bald patches on a normal or occasionally, slightly reddish skin.
  • Broken hairs may be seen in the bald patch. They have broken-off stubbled ends and are often referred to as exclamation mark hairs because of their appearance.
  • The scalp is most commonly affected. Less commonly affected areas include the eyebrows, eyelashes, pubic hair and beard.
Complications
Alopecia areata may occasionally lead to widespread hairloss causing:
  • Alopecia totalis which causes total baldness of the scalp.
  • Alopecia universalis where the hairloss affects the entire body including eyebrows, armpit and the pubic hair.
       

    Muliple patches of alopecia areata.
    Click on image for larger view.
     

    Severe alopecia areata progressing to alopecia universalis.
    Click on image for larger view.