|Diseases And Disorders Of The Skin
Diseases and disorders of the skin can be classified under seven categories:
1. Congenital: Exists at birth, may be inherited.
2. Bacterial: Bacteria are single-celled organisms found both inside and outside the body. Some are harmful and others are good for us. They can invade normal skin areas or wounds.
3. Viral: Viruses are sub-microscopic organisms that can only multiply once inside cells they have invaded.
4. Fungal: An organism that can live on skin, hair and nails and thrives in warm, moist conditions.
5. Pigmentation Disorders: A number of pigments contribute to skin color, for example melanin. This can accumulate more or less intensively in some areas.
6. General: Other features visible on the skin surface which may be considered a disorder.
7. Skin Cancer: There are 3 main types of skin cancer. The leading cause of all types is excessive exposure to sunlight.
Eczema: Eczema can be found all over the body but most often on the inside of the knee (in the popliteal space) and elbow joints, on the face, hands and scalp. The skin becomes extremely dry and itchy causing great discomfort. Skin has scaly dry patches with bleeding at points. Not contagious.
Psoriasis: Chronic inflammatory skin disease characterized by red patches covered with silvery scales that are constantly shed. Size of scales vary from minute spots to quite large sheets of skin. Points of bleeding may occur beneath scales. Affects whole body or specific areas, like face and scalp. Not infectious.
Rosacea: Gives a flushed, reddened appearance. Occurs on the face, this condition can be aggravated by anything causing vasodilation - heat, sunshine, spicy food, alcohol, cold. Affects both men and women especially menopausal women. Not related to acne vulgaris. Not contagious.
Acne vulgaris: Normally caused by hormonal imbalances which increase sebum production leading to blocked glands and infection. The skin has a shiny, sallow appearance with papules, pustules and comedones. It is prone to open pores. Where pustules have cleared there is often pitting and scarring. The main sites for infection are the face, back, chest and shoulders. Not contagious.
Spots: What is a spot?: A bacterial infection of the skin, causing inflammation around a hair follicle.
Carbuncles: A skin infection that often involves a group of hair follicles. The infected material forms a lump which occurs deep in the skin.
Folliculitis: Bacterial infection of the pilo-sebaceous duct (sebaceous gland and hair follicle) causing inflammation. Common in adolescence. Possible link with acne vulgaris.
Impetigo: A bacterial infection causing thin-roofed blisters which weep and leave a thick, yellow crust. Highly contagious.
Syphilis: Syphilis is a bacterial STD which is caught through sexual contact. An open sore (called a chancre) on the genital area is one symptom of the disease.
Chancroid: Raised sore in the vulva or vaginal area, caused by chancroid, a bacterial STD.
Warts: A small horny tumor found on the skin, often on fingers and thumbs. Caused by viral infection. Genital warts are warts which are transferred through sexual contact. Highly contagious.
Verrucas: Warts found on the feet. Highly contagious.
Herpes simplex: A viral infection commonly known as cold sores; not confined to the mouth, can spread over the face and other parts of the body. Genital herpes is an STD which manifests as sores in the genital area. Appears as small blisters which if left alone will dry up leaving a crust which falls off. Highly contagious when active. See, how to treat cold sores.
Herpes zoster: A viral infection commonly known as shingles. Adult form of chicken pox. Usually affects spinal nerves and one side of the thorax. Highly contagious.
Tinea corporis, pedis: Infections which attach themselves to keratinised structures like the skin. Tinea corporis is commonly known as ringworm and can be found anywhere on the body. Tinea pedis is commonly known as athlete's foot. Highly infectious. See, how to treat athlete's foot.
Pediculosis: The infestation with lice resulting in severe itching. This can occur on the head (capitis), body (corporis) and pubic (pubis) areas. Pubic lice, also known as crabs, is an infestation of lice in the hairs of the pubic region.
Scabies: Scabies is a contagious skin infection caused by the itch mite; characterized by persistent itching and skin irritation.
Dermatosis Papulosa Nigra: Is a condition of many small, benign skin lesions, characterized by dark-brown papular lesions on the face and upper body, mainly found on a black skin.
Papilloma: Benign epithelial tumor forming a rounded mass.
Vitiligo: Complete loss of color in well-defined areas of the face and limbs. A form of leucoderma (an abnormal whiteness of the skin due to absence of pigmentation); begins in patches but may converge to form fairly large areas; most obvious in darker skins.
Albinism: Complete lack of melanocytes resulting in lack of pigmentation in skin, hair and eyes. Sufferers have poor eyesight and extreme ultraviolet sensitivity. This is an inherited condition.
Chloasma: Butterfly mask often caused by pregnancy and the contraceptive pill; a hyper pigmentation condition involving the upper cheeks, nose and occasionally forehead. Discoloration usually disappears spontaneously at the end of pregnancy.
Ephelides/Freckles: Small pigmented areas of skin which become more evident on exposure to sunlight and are found in greatest abundance on the face, arms and legs; fair-skinned individuals are more prone to freckles.
Lentigo: Also known as liver spots; dark patches of pigmentation which appear more distinct than freckles and have a slightly raised appearance and more scattered distribution.
Moles (papilloma): Common occurrence on the face and body and present in several different forms, varying in size, color and vascular appearance. Flat moles are called sessile whilst those raised above the surface, or attached by a stalk are pedunculated. See, what are skin moles?
Naevae: Birth mark; if pigmented may occur on any part of the body and are often found on the neck and face, being sometimes associated with strong hair growth. Vary in size from pinhead to several centimeters and in rare cases may be extremely large. Pigmentation varies from light brown to black. Strawberry naevae (pink or red birth marks) often affect babies, eventually disappearing after a few years.
Port wine stain: A large area of dilated capillaries causing a pink to dark red skin color which makes it contrast vividly with the surrounding skin. The stain is commonly found on the face.
Blisters: An elevation of the skin filled with serous fluid. Did you know? The surface of a blister is made of raised epidermis and the fluid inside it is serum. How to treat blisters.
Cyst: A harmless swelling filled with air, fluids or semi-solid material. The cyst is enclosed by a layer of epidermis which can be removed painlessly because it contains no nerves or blood vessels.
Keloid scars: A scar that forms at the site of a healed wound. Keloids are rubbery, firm raised areas of skin that can vary in color.
Striae: Another name for stretch marks. .
Skin tags: Medically termed verrucae filliformis, skin tags are small flaps of excess skin typically found in the neck, groin and armpits. They are harmless and may eventually fall off.
Xanthomas: Raised bumps in the skin that contain yellow fatty deposits, linked to high levels of cholesterol.
Burns: Skin injury caused by exposure to flame, heat or friction.
Cellulitis: Inflammation of tissues beneath the skin. It is characterized by fever, redness, swelling and pain.
Staph Infection: Methicillin-resistant Staphylococcus aureus (MRSA): A dangerous, potentially life-threatening infection caused by Staphylococcus aureus bacteria (commonly called a Staph infection) that is resistant to the broad spectrum antibiotics commonly used to treat it.
Pressure sores/bed sores: Ulcers (open sore) that appear on areas of the skin which are under pressure from lying in bed, wearing a cast, sitting in wheelchairs, or being immobile for long periods of time.
Broken capillaries: Appear as small thin threads under the skin, typically on the face. Sometimes referred to as spider veins. It happens when the tiny blood vessels (capillaries) near the surface of the skin dilate. This may be hereditary or caused by other factors such as spicy foods or drinking too much alcohol.
Crow's feet: Fine lines (wrinkles) around the eyes caused by habitual expressions (squinting or laughing) and daily movement. The premature appearance of crow's feet may be due to eye strain and is often associated with edema (swelling) around and under the eyes. See, What are wrinkles?
UV/Sun damage: UV rays stimulate rapid production of the basal cells. This in turn causes the stratum corneum to thicken and dry out. Over exposure to UVA can lead to premature ageing and over-exposure to UVB is linked to skin cancer. See, how to treat sunburn.
Urticaria - hives, nettle rash: Usually an allergic reaction to a product, food or plant. Urticaria is characterized by welts which are pinkish in color. Very itchy. Can lead to secondary infection by bacteria through scratching.
Allergic reaction: When the skin or body is irritated, it produces histamine (part of the defense mechanism) in the skin. This can cause red, blotchy patches on the skin, stinging, watery, eyes, swellings and a runny nose. Reaction can be slight or intense.
Comedones/blackheads: Blackheads are caused by a build-up of oil secretions which have become trapped in the hair follicles and have subsequently dried out and hardened. The dark color comes from oxidation (contact with the air). More common in puberty when oil production is naturally higher.
Dermatitis: Allergic inflammation of the skin. Main symptom is erythema - skin redness, itching and skin lesions. Also known as contact dermatitis, there are many causes including clothing, cosmetics, chemicals, plants and drugs. Not contagious.
Milia/whiteheads: Tiny white bumps on the skin. Whiteheads form when sebum (oil) becomes trapped in a blind duct with no surface opening. The condition is most common on dry skin and milia appear on the eyelids and between the eyebrows. Milia can form after injury, e.g. sunburn on the face or shoulders, and are sometimes widespread.
Bromidrosis/osmidrosis: Fetid or foul-smelling perspiration which is caused by decomposition of the sweat and cellular debris by the action of bacteria and yeasts.
Anhidrosis: The reduced ability or inability to sweat.
Hyperhidrosis: Is the condition characterized by abnormally increased perspiration.
Basal cell carcinoma:
Occurs on exposed parts of the skin, especially face, nose, eyelid, cheek.
Squamous cell carcinoma:
Squamous cells are those found on the surface of the body, on the top layer of the skin. Squamous cell carcinoma is said to be caused by sunlight, chemicals or physical irritants. It starts very small but grows rapidly, becoming raised.
A malignant tumor of melanocytes. It usually develops in a previously benign mole. The mole has become larger and darker, ulcerated and the tumor eventually spreads.
Other Useful Articles
What is my skin type? Oily, sensitive or dry?
When does the skin start to age? Early signs of crows feet and wrinkles.
Treatments for female hair loss: Tips and medical treatments.
How to treat rashes: General rashes caused by hives, allergies and so on.
What ingredients are in skin creams? Understanding the active ingredients in your moisturizer.