Skin diseases

1. Skin diseases Group Presentation Bench # 1 Marie-Josee Lizaire Aaron Nicholas Kent …… Miami Dade College Spring Term 2008-2 Anatomy & Physiology I Lab / Monday 2:30PM Prof. Fernandez Clemente April 2009

2. Sclerotic skin diseases Skin diseases associated with post-transplant immunosuppression Cutaneous T-Cell Lymphoma Acne Atopic dermatitis (Eczema) Pruritus (itch) including: Psoriasis Allergic contact dermatitis dry skin prurigo nodulaaris urticaria dermatitis herpetiformis lichen simplex Definition Skin : the primary interface between the body and the environment is susceptible to disorders caused by chemical and microbial agents, thermal andelectromagnetic radiation, and mechanical trauma. The most damaging consequence of the disruption of skin is invasion by pathogenic microorganisms, and the need for an effective means of protection against this challenge has been a fundamental force behind the evolution of the immune system. Types of Skin diseases

3. Acne • Aggravating factors • Genetic factors (family members have bad acne) • Hormonal factors (higher levels of androgenic hormones) due to: • Polycystic ovaries (common) • Enzyme deficiency eg sterol hydroxylase deficiency (very rare) • Excessive corticosteroids • Psychological stress and depression • Environmental factors such as: • High humidity causing swelling of the skin • Cosmetics especially certain moisturisers, foundation and pomades (watch out for lanolin, petrolatum, vegetable oils, butyl stearate, lauryl alcohol and oleic acid) • Petroleum oils • Pressure from headbands & chin straps (eg: "fiddler's neck") • Dietary factors such as • excessive dairy products (controversial). Most people develop acne during adolescence (most prevalent in those aged 16 to 18 years). Acne usually becomes less of a problem after the age of 25 years, although about 15% of women and 5% of men continue to have acne as adults. Individual acne lesions usually last less than two weeks but the deeper papules and nodules may persist for months. Acne vulgaris (a common type of acne ) may occur on the face, chest, back and sometimes even more extensively. Several types of acne spots occur, often at the same time. Causes • higher levels of sex hormones at puberty • Convertion of theses hormones in the skin to dihydrotestosterone (DHT) which stimulates oil glands to enlarge. • Production of sebum. • Development of comedones • Types • Non-inflammatory lesions • Inflammatory lesions : Bacteria and comedonal debris cause acne pimples or pustules • Comedones and inflammatory lesions are usually considered separately. • Secondary lesions

4. What does acne look like?

5. Atopic dermatitis (eczema) What is atopic dermatitis? • It is a chronic, itchy skin condition that is very common in children but may occur at any age. • Also known as eczema and atopic eczema, it is the most common form of dermatitis. • Usually occurs in people who have an 'atopic tendency‘, i.e. who may develop any or all of three closely linked conditions; atopic dermatitis, asthma and hay fever (allergic rhinitis). • It is not contagious! It arises because of a complex interaction of genetic and environmental factors. These include skin irritants, the weather, temperature and non-specific triggers: see Causes of atopic dermatitis. • Infants less than one year old often have widely distributed eczema. The skin is often dry, scaly and red with small scratch marks made by sharp baby nails. • Many children develop a 'nummular' pattern of atopic dermatitis. This refers to small coin-like areas of eczema scattered over the body. These round patches of eczema are dry, red and itchy and may be mistaken for ringworm (a fungal infection). • Adults who have atopic dermatitis may present in various different ways. They may continue to have a diffuse pattern of eczema but the skin is often more dry and lichenified than in children.

6. What does atopic dermatitis look like?

7. Pruritus : an unpleasant sensation on the skin that provokes the desire to rub or scratch the area to obtain relief. It can cause discomfort and frustration; in severe cases it can lead to disturbed sleep, anxiety and depression. Causes Hormonal - 2% of pregnant women have pruritus without any obvious dermatological cause. In some cases the itch is due to cholestasis (pooling of bile in the gall bladder and liver). It usually occurs in the 3rd trimester and is relieved after giving birth. - Itch is a common symptom of menopause. Exposure related (Insects and infestations) Systemic diseases (kidney, liver, endocrine/metabolic, blood, nervous system) Localised pruritus Scalp Back Arm Hand Groin Anus Leg Feet Pruritus (itch)

8. What does pruritis (itch) / psoriasis look like?

9. Measures of Prevention and Treatment Acne • Acne may be considered mild, moderate or severe. • Comedones and inflammatory lesions are usually considered separately. • Apply an oil-free moisturizer only if the affected skin is obviously peeling. • Avoid applying oily cosmetics such as foundation or sunscreen • Antiseptic washes (Suitable topical agents for mild acne without prescriptions) • Blue light acne treatment is a new procedure recently found to be safe and helpful for mild to moderate acne. • Antibiotics such as tetracycline, minocycline, doxycycline or erythromycin (as Suitable oral medications) • Treatment for severe acne requires oral treatment • Sunlight is anti-inflammatory and can help briefly. However, exposure to ultraviolet radiation results in ageing skin and can eventually lead to skin cancer. • Comedones can be expressed or removed by cautery or diathermy. • Lasers and other light systems appear helpful for acne • Which treatment is best depends on the patient's age and sex, the extent and the severity of the acne. .

10. Psoriasis Avoid precipitating factors such as rough clothing or fabrics, overheating, and vasodilators if they provoke itching (e.g. caffeine, alcohol, spices). Fingernails should be kept short and clean. If the urge to scratch is irresistible then rub the area with your palm Topical treatment for pruritus: Cool the skin with wet dressings or a tepid shower Calamine lotion: avoid on dry skin and limit use to a few days (contains phenol) Menthol/camphor lotion: gives a chilling sensation Regular use of emollients, especially if skin is dry Mild topical corticosteroids for short periods Medications For severe pruritus (disturbed sleep) : treatment with oral medication Aspirin: effective if kinin or prostaglandin mediated pruritus (but may aggravate itch in some patients). Doxepin or amitriptyline: tricyclic antidepressants with effective antipruritic action. Antihistamines Anti-epileptic drugs such as gabapentin and pregabalin (some patients). Thalidomide (very successful in treating nodular prurigo and chronic pruritus of various kinds). Opioid antagonists such as butorphanol intranasal spray and naltrexone tablets Available treatment and Medications

11. References • The New England Journal of Medicine http://content.nejm.org/cgi/content/extract/341/24/1817 http://dermnetnz.org/acne/acne-causes.html http://search.atomz.com/search/?sp_a=sp1001e79f&sp_f=iso-8859-1&sp_q=eczema