Skin Disorders (Dermatology) 402

Transcription

1 Skin Disorders (Dermatology) 402 By Dr Maxwell Adibe FUNCTIONS OF THE SKIN The skin or the integument is a vital organ A protective wrap Regulates body temperature Senses pain Keeps harmful substances & microorganisms from entering body Provides a shield from harmful effects of the sun Largest organ of the human body FUNCTIONS OF THE SKIN Indicates malfunction within the body through color changes Cyanosis (blue) is lack of O2-cardiovascular problem Jaundice (yellow) indicates liver disease from accumulation of bilirubin in the blood Abnormal redness due to polycythemia, carbon monoxide poisoning, & fever Pallor (whitening) may indicate anemia 1

2 STRUCTURE OF THE SKIN Each layer of skin performs specific tasks OUTERMOST layer is the EPIDERMIS Consists of stratified or squamous epithelium Top layer of epidermis contains KERATIN a tough, fibrous protein that protects skin from harmful substances Bottom layer of epidermis contains MELANIN dark pigment in skin that protects body from harmful rays of the sun II. STRUCTURE OF THE SKIN DERMIS True Skin lies below the epidermis Composed of connective tissue Supports blood & lymph vessels, elastic fibers, nerves, hair follicle, sweat glands & sebaceous (oil) glands SUBCUTANEOUS lies under the dermis Connects the skin to underlying structures (i.e. muscle, fat) Contains adipose (fat cells) tissue helps insulate body from cold & heat Structure of the Skin 2

3 CLASSIFICATIONS OF SKIN DISEASES Skin diseases are identified and classified according to characteristic lesions (size, shape, color & location) and other S & Sx s PRURITIS itching EDEMA swelling ERYTHEMA redness Inflammation usually accompany lesions and are helpful in making a diagnosis (DX) CLASSIFICATIONS OF SKIN DISEASES VESICLES small blister-like eruptions or larger fluid-filled lesions called bullae. PUSTULES lesions that contain pus MACULAR flat lesions PAPULAR raised lesions ERYTHEMATOUS reddened area due to inflammation &/or injury Nodules & tumors hard to the touch Pruritis itching, which accompanies many skin diseases, especially allergic & parasitic What is this? 3

4 Acne Acne Vulgaris Acne is a self-limited disorder primarily of teenagers & young adults. Acne is a disease of pilosebaceous follicles. 4 factors are involved: Retention hyperkeratosis Increased Sebum production Propionbacterium acnes within the follicle Inflammation Acne Vulgaris External Factors that contribute to Acne Oils, greases, dyes in hair products Detergents, soaps, astringents Occlusive clothing: turtlenecks, bra straps Environmental Factors: Humidity & Heavy exercise. Psychological stress Diet is controversial 4

5 Acne Vulgaris Acne vulgaris typically affects those areas of the body that have the greatest number of sebaceous glands: the face, neck, chest, upper back, and upper arms. In addition to the typical lesions of acne vulgaris, scarring and hyperpigmentation can also occur. Hyperpigmentation is most common in patients with dark complexions Acne Vulgaris Classification of Acne Type 1 Mainly comedones with an occasional small inflamed papule or pustule; no scarring present Type 2 Comedones and more numerous papules and pustules (mainly facial); mild scarring Type 3 Numerous comedones, papules, and pustules, spreading to the back, chest, and shoulders, with an occasional cyst or nodule; moderate scarring Type 4 Numerous large cysts on the face, neck, and upper trunk; severe scarring Acne Vulgaris 5

6 What is this? Acne Rosacea Rosacea is an acneiform disorder of middle-aged and older adults. Characterized by vascular dilation of the central face, including the nose, cheek, eyelids, and forehead. The cause of vascular dilatation in rosacea is unknown. The disease is chronic. Acne Rosacea rosacea is a chronic disorder characterized by periods of exacerbation and remission. Increased susceptibility to recurrent flushing reactions that may be provoked by a variety of stimuli including hot or spicy foods, drinking alcohol, temperature extremes, and emotional reactions. The earliest stage of rosacea is characterized by facial erythema and telangiectasias. 6

7 Acne Rosacea Patients with rosacea may develop severe sebaceous gland growth that is accompanied by papules, pustules, cysts, and nodules. The diagnosis of rosacea is based upon clinical findings(1 or more of the following): Flushing (transient erythema) Non-transient erythema Papules and pustules Telangiectasia Acne Rosacea Topical antibiotics or benzoyl peroxide are the initial treatments of choice. Tretinoin cream is used in patients with papular or pustular lesions that are unresponsive to other treatments. The chronicity of rosacea requires that medical therapy be continued long-term, not just for flareups of the condition. What is This? 7

8 Allergic Contact Dermatitis Contact dermatitis refers to any dermatitis arising from direct skin exposure to a substance. It can be allergic or irritant-induced. An allergen induces an immune response, while an irritant directly damages the skin. Allergic Contact Dermatitis The most common sensitizer in North America is the plant oleoresin urushiol found in poison ivy, poison oak, and poison sumac Other common sensitizers in the US: nickel (jewelry) formaldehyde (clothing, nail polish), fragrances (perfume, cosmetics), preservatives (topical medications, cosmetics), rubber chemicals in shoes (both leather and synthetic) Allergic Contact Dermatitis Treatment Avoidance of exposure to the offending substance. Use of corticosteroids topical or oral in the acute phase of the reaction maybe helpful. Cooling of the skin by using calamine lotion or aluminum acetate 8

9 What is this? Psoriasis Psoriasis is a common chronic skin disorder typically characterized by erythematous papules and plaques with a silver scale. Most of the clinical features of psoriasis develop as a secondary response triggered by T-lymphocytes in the skin. Psoriasis Several clinical types of psoriasis have been described: Plaque psoriasis - symmetrically distributed plaques involving the scalp, extensor elbows, knees, and back. Guttate psoriasis - abrupt appearance of multiple small psoriatic lesions. Pustular psoriasis - most severe form of psoriasis. Characterized by erythema, scaling, and sheets of superficial pustules with erosions. Inverse psoriasis - refers to a presentation involving the intertriginous areas. 9

10 Psoriasis Nail psoriasis -the typical nail abnormality in psoriasis is pitting w/ color changes & crumbling of the nail. Psoriasis Psoriasis Most patients w/ psoriasis tend to have the disease for life. There is variability in the severity of the disease overtime w/ complete remission in 25% of cases. The diagnosis of psoriasis is made by physical examination and in some cases skin biopsy. 10

11 Psoriasis Treatment Treatment modalities are chosen on the basis of disease severity. Topical emmollients, topical Steroids, tar Calcipotriene(Dovonex) affects the growth and differentiation of keratinocytes via its action at the level of vitamin D receptors in the epidermis. Tazarotene, is a topical retinoid, systemic retinoids Methotrexate, cyclosporine Immunmodulator therapy (embrel, remicade) Ultraviolet light. What is this? Vitiligo Vitiligo is an acquired skin depigmentation that affects all races but is far more disfiguring in blacks. The precise cause of vitiligo is unknown Genetic factors appear to play a role percent of patients may have a family history of the disorder. The pathogenesis is thought to involve an autoimmune process directed against melanocytes. 11

12 Vitiligo Peaks in the second and third decades. The depigmentation has a predilection for acral areas and around body orifices (eg, mouth, eyes, nose, anus). The course usually is slowly progressive. The diagnosis of vitiligo is based upon the clinical presence of depigmented patches of skin Vitiligo Repigmentation therapies include: corticosteroids calcineurin inhibitors Ultraviolet light Pseudocatalase cream Surgery minigrafting techiniques Depigmentation therapy w/ hydroquinone What is this? 12

13 Pityriasis Rosea Pityriasis rosea is an acute, self-limited, exanthematous skin disease characterized by the appearance of slightly inflammatory, oval, papulosquamous lesions on the trunk & proximal areas of the extremities. The eruption commonly begins with a "herald" or "mother" patch, a single round or oval, rather sharply delimited pink or salmon-colored lesion on the chest, neck, or back. 2 to 5 cm in diameter. Pityriasis Rosea Pityriasis Rosea A few days later lesions similar in appearance to the herald patch, appear in crops on the trunk & proximal areas of the extremities. The eruption spreads centrifugally or from the top down in just a few days. The long axes of these oval lesions tend to be oriented along the lines of cleavage of the skin, like a christmas tree pattern. Then the lesions fade without any residual scarring. 13

14 Pityriasis Rosea The presence of a herald patch by history or on examination. The characteristic morphology and distribution of the lesions. The absence of symptoms other than pruritus combine to make PR an easy diagnosis in most instances. Pityriasis Rosea Differential Dx include: Psoriasis, secondary syphilis, tinea corporis, Lyme disease, & drug eruptions. Treatment is usually reasurrance. Topical Steroids Antipruitic lotions (prax, pramagel) Phototherapy Erthyromycin in severe cases Rash usually persists for 2-3 months What is this? 14

15 Cellulitis Cellulitis is an infection of the skin with some extension into the subcutaneous tissues. An extremity is the most common location but any area of the body can be involved. Cellulitis Five factors were identified as independent risk factors: Lymphedema Site of entry (leg ulcer, toe web intertriginous, and traumatic wound) Venous insufficiency Leg edema Being overweight Cellulitis Cellulitis is a recognizable clinical syndrome with both local & systemic features. Systemic symptoms include: Fever and chills Myalgias Increased WBC count 15

16 Cellulitis Local findings typical of cellulitis: Macular erythema that is largely confluent Generalized swelling of the involved area Warmth to the touch of the involved skin Tenderness in the affected area Tender regional lymphadenopathy is common Lymphangitis may be present Abscess formation also may be present Cellulitis Cellulitis in the majority of patients is caused by beta-hemolytic streptococci groups A, B, C, G, and Staphylococcus aureus. Other less common pathogens include H.flu, P.aeruginosa, Aermonas hydrophilia, Pasturella multocida. Cellulitis Diagnosis is clinical Treatment: Anti-strep/Anti- staph Cefazolin Nafcillin Clindamycin Vancomycin Fluoroquinolones (3 rd & 4 th generations) Macrolides (erythromycin, azithromycin) Duration of treatment is usually days 16

17 What is this? Erysipelas Erysipelas is a characteristic form of cellulitis that affects the superficial epidermis, producing marked swelling. Bacterial Organisms: Beta-hemolytic streptococci group A Group C & G less commonly Staph. Aureus Streptococcus pneumoniae, enterococci, gram negative bacilli Erysipelas The erysipelas skin lesion has a raised border which is sharply demarcated from normal skin. This is its most unique feature and allows it to be distinguished from other types of cellulitis. The demarcation is sometimes seen at bony prominences. The affected skin is painful, edematous, intensely erythematous, and indurated (peau d'orange appearance). 17

18 Erysipelas The face historically was the most common area of involvement. Erysipelas is diagnosed clinically It can mimic other skin conditions: Herpes zoster (5 th cranial nerve) Contact Dermatitis Urticaria Erysipelas Treatment: Penicillin is the preferred treatment Erythromycin Clindamycin Fluoroquinolones Erysipelas does have the propensity of recur. What is this? 18

19 Ecthyma Ecthyma is an ulcerative pyoderma of the skin caused by group A beta-hemolytic streptococci. Because ecthyma extends into the dermis, it is often referred to as a deeper form of impetigo. Preexisting tissue damage (excoriations, insect bites, dermatitis) & immunocompromised states ( diabetes, neutropenia) predispose patients to the development of ecthyma. Ecthyma Ecthyma begins as a vesicle or pustule overlying an inflamed area of skin that deepens into a dermal ulceration with overlying crust. A shallow, punched-out ulceration is apparent when adherent crust is removed. The deep dermal ulcer has a raised and indurated surrounding margin. Ecthyma lesions can remain fixed in size or can progressively enlarge to cm in diameter. Ecthyma heals slowly and commonly produces a scar. Regional lymphadenopathy is common. Ecthyma Treatment: Topical mupirocin ointment Gentle surgical debridement Oral/IV antibiotics Penicillin Clindamycin Macrolides Cefazolin 19

20 What is this? Tinea Vesicolor Tinea versicolor is a common superficial infection caused by the organism Pityrosporum orbiculare. Which is a saprophytic yeast that is part of the normal skin flora. Tinea Vesicolor Lesions can be hypopigmented, light brown, or salmon colored macules. A fine scale is often apparent, especially after scraping. Individual lesions are typically small, but frequently coalesce. Lesions are limited to the outermost layers of the skin. 20

21 Tinea Vesicolor Most commonly found on the upper trunk & extremities, & less often on the face and intertriginous areas. While most patients are asymptomatic, some complain of mild pruritus The diagnosis of tinea versicolor is confirmed by direct microscopic examination of scale with 10 % potassium hydroxide (KOH). Tinea Vesicolor The differential diagnosis includes seborrhea, eczema, pityriasis rosea, and secondary syphilis. Treatment includes topical antifungals. Oral antifungals can be used for more extensive disease: Ketocanozole 400mg x 1 dose. Fluconazole and itraconazole are also effective. What is this? 21

22 Cutaneous Warts Cutaneous warts AKA verrucae are caused by HPV which infects the epithelium of skin and mucus membranes. Cutaneous warts occur most commonly in children and young adults. Also more common among certain occupations such as handlers of meat, poultry, and fish. Predisposing conditions include atopic dermatitis & any condition in which there is decreased cellmediated immunity. Cutaneous Warts Infection with HPV occurs by skin-to-skin contact Incubation period following exposure in 2-6 months. Warts can have several different forms based upon location & morphology (flat, mosaic, and filiform warts) Lesions may occur singly, in groups, or as coalescing lesions forming plaques. Cutaneous Warts The diagnosis of verrucae is based upon clinical appearance. Scrape off any hyperkeratotic debris & reveal thrombosed capillaries (seeds). The wart also will obscure normal skin markings 22

23 Cutaneous Warts Differential Diagnosis: Lichen Planus Seborrheic Keratosis Acrochordon or skin tag Clavus or corn Treatment Spontaneous regression in 2/3 over 2yrs Salicylic acid, liquid nitrogen, cantharidin Immunotherapy, intralesional injections What is this? Secondary Syphilis Syphilis is a chronic infection caused by the bacterium Treponema pallidum which is sexually transmitted. Syphilis occurs in 3 stages: 1 st stage is characterized by the classic chancre, which is a 1-2cm ulcer with raised indurated borders, usually painless and occurs at site of innoculation. Heals spontaneously. 23

24 Secondary Syphilis Secondary Syphilis Secondary or systemic syphilis is characterized by a rash. The rash is classically a symmetric papular eruption involving the entire trunk & extremities including the palms and soles. Systemic symptoms include fever, headache, malaise, anorexia, sore throat, myalgias, & weight loss. Lymphadenopathy (inquinal, axillary) So-called "moth-eaten" alopecia Condyloma lata, grayish white lesions involving the mucus membranes Secondary Syphilis 24

25 Secondary Syphilis Diagnosis at this stage is usually by serologic testing but darkfield microscopy can also be done for direct visualization of spirochete. Non-treponemal testing: Veneral disease research laboratory (VDRL) Rapid plasma reagent (RPR) Treponemal testing: Fluorescent treponemal antibody absorption test Microhemagglutination test for antibodies Seconday Syphilis Treatment T.Pallidum remains very sensitive to PCN. Long-acting benzathine penicillin G should be used. If documented chancre was done in the past 1 yr, one IM dose is appropriate. If neither of the above applies this needs to treated as latent syphilis and 3g weekly doses must be given. Doxycycline, erythromycin or zithromycin in pen allergic patients x 14 days. What is this? 25

26 Herpes Zoster Reactivation of endogenous latent infection within the sensory ganglia results in herpes zoster or "shingles", a syndrome characterized by a painful, unilateral vesicular eruption in a restricted dermatomal distribution. How the virus emerges from latency is not clearly understood. Patients frequently experience a prodrome of fever, pain, malaise and headache which precedes the vesicular dermatomal eruption by several days. Herpes Zoster The rash initially appears along the dermatome as grouped vesicles or bullae which evolve into pustular or occasionally hemorrhagic lesions within three to four days. The thoracic and lumbar dermatomes are the most commonly involved sites of herpes zoster. The complications of herpes zoster include ocular, neurologic, bacterial superinfection of the skin and postherpetic neuralgia Herpes Zoster Treatment Antivirals: Acyclovir Famciclovir Valacyclovir Antivirals w/ corticosteroids Analgesics: opioids/acetominophen 26

27 What is this? Actinic Keratosis Actinic keratoses (AKs) are premalignant lesions that develop only on sun-damaged skin. AKs appear as patches of hyperkeratosis with some surrounding erythema on sun-exposed areas of the head and neck, forearms and hands, and upper back. Actinic Keratosis 27

28 Actinic Keratosis The differential diagnosis of AKs includes seborrheic keratoses, verruca vulgaris, SCC, and superficial BCC. The treatment of AKs begins with prevention. Avoiding sun exposure sunscreens reduce the development of AKs, Active treatment of AKs depends upon the size of the lesion and the number of lesions present. Liquid Nitrogen Surgical curettage Chemotherapy (5-FU, diclofenac, imiquimod) Dermabrasion Photodynamic therapy Which one is which? Basal Cell Carcinomas begins as small shiny nodules and grows slowly. It is the most common form of skin cancer. Frequently, the central portion breaks down to form an ulcer with a reddish-purple scab. These tumors usually remain fairly localized and rarely spread elsewhere. 28

29 Squamous Cell Carcinoma is another common form of skin cancer. When these tumors first appear they are firm to the touch. They appear most often on sun-exposed areas of your body. Squamous cell carcinoma evolves very slowly through a premalignant stage known as a solar or actinic keratosis. Untreated, significant numbers of these lesions can metastasize to distant sites. Tumors on the lower lip and ears are at higher risk to spread. Malignant Melanoma is the most dangerous form of skin cancer. They arise from either pre-existing moles or normal skin. Malignant melanoma, like basal and squamous carcinomas, is linked to overexposure to the sun. But it can appear any place on your body. When detected early & with proper treatment, the recovery rate from this form of skin cancer can be very high. References Harrison s 15 th Edition. Principles of Internal Medicine Up to Date Emedicine Dermatology Pearls Adult and Pediatric 29

30 Thank You 30