Disease Of Skin Appendages General hospital of Tianjin medical university Suju Luo

Normal skin skin appendages ★sebaceous ★hair ★sweat gland

Disease Of Skin Appendages 1 Disorders of sebaceous glands(acne vulgaris ; rosacea; seborrheic dermatitis) 2 Disorders of sweat glands(hyperhidrosis, hypohidrosis, miliaria) 3 Disorders of hair (alopecia areata, alopecia androgenitica, hypercrichosis and hirsutism)

acne vulgaris

Acne Vulgaris Acne vulgaris is a follicular disorder, a disease of the pilosebaceous unit. Characterized by comedones (whitehead or blackhead), papules, pustules ,cysts, nodules, and scars. Sites of predilection are face, neck, and upper trunk

Acne Vulgaris Pathogenesis: ★follicular epidermal hyperproliferation, obstruction of the pilosebaceous canal ★excessive sebaceous gland secretion ★ inflammation ( arising as a result of leakage of contents of the pilosebaceous follicle into the surrounding dermis) ★the presence of Propionibacterium acnes

The process of inflammatory acne formation excessive production of sebum and keratin obstruction of the pilosebaceous canal rupture of the follicular wall, releasing the contents into the dermis and initiating an inflammatory response papules, pustules ,cysts

Acne Vulgaris the comedones, open or closed

Inflammatory acne

upper trunk.

Treatment topical treatment is needed for mild acne  benzoyl peroxide-containing preparations topical antibiotics-erythromycin and tetracycline topical vitamin A acid-tretinoin ④antiseptics and keratolytics

Treatment systemic treatment is needed for moderate acne and severe acne antibiotics---minocycline or erythromycin hormones---Dianette retinoids and isotretinoin for severe or persistent cases

Treatment Stepped care ★for mild acne topical preparations only ★for moderate acne topical preparations + systemic antibiotics ★for severe acne topical preparations + systemic antibiotics +/or isotretinoin if necessary use hormones(Dianette) for female case

Rosacea

Rosacea Introduction: relatively common woman more than man man more severe and complications such as keratitis and rhinophyma

two cardinal clinical components of the disease: ★(1)Vascular change consisting of persistent erythema and flush. ★(2)acneiform eruption presents as papules, pustules, nodules, cyst and sebaceous hyperplasia

Rosacea Clinical features: (1)30-50 years old people affected (2)mainly on the area of the nose, cheeks, chin and forehead (3)flushing and erythema first persistent erythema, telangiectasia，papules and pustules, nodules and cysts rhinophyma no comedones and seborrhoea (4)ocular complications

erythema , papules and pustules , telangiectasia

on the butterfly area of the face, flushing, erythema ,papules and pustules

severe Rosacea ,on the butterfly area of face flushing and erythema , papules and pustules, rhinophyma.

Treatment Topical treatment Systemic treatment 0.75% metronidazole, 5%benzoyl peroxide et al. Systemic treatment antibiotics---minocycline or erythromycin or metronidazole isotretinoin Laser surgery or electrocoagulation Surgery

1 Disorders of sebaceous glands ★ seborrheic dermatitis ★ acne vulgaris ★ rosacea

Seborrheic dermatitis

Seborrheic dermatitis Clinical features: characterized by erythematic, yellowish, greasy scales with pruritus, burning and dryness distributed over the sebaceous sites (the scalp, the faces, the nasolabial folds, eyebrows, ears, upper trunk and flexures.

Pathogenesis: linked with yeast Malassezia, immunologic abnormalities, sebaceous activity and patient susceptibility Variants: Infantile seborrheic dermatitis Seborrheic dermatitis of adolescents and adults

Infantile seborrheic dermatitis due to the transplacental transfer of maternal androgens to the newborn which stimulate the sebaceous glands marked by erythematous, adherent, waxy scaling of the scalp may also develop circumscribed, yellow red, scaly plaques over the trunk, diaper area and flexural folds

Seborrheic dermatitis of adolescents and adults non inflammatory, greasy desquamation over the scalp→scaling and inflammation occur in other seborrheic areas: eyebrows, base of eyelashes, nasolabial folds, external ear canals, posterior auricular fold and presternal area

Treatment ＊topical steroids ＊respond to tar shampoos, 2.5 percent selenium sulfide ＊Systemic ketoconazole

Disorders of sweat glands eccrine glands sweat glands apocrine glands

Disease Of eccrine sweat glands most numerours eccrine sweat glands on the palms, soles and in the axillae important role in manitaining homeostatic balance and temperature control

Disease Of eccrine sweat glands (1)Hyperhidrosis excessive production of eccrine sweat in response to heat or emotional stimuli caused by enhanced perspiration from the eccrine glands generalized (caused by heat) localized (caused by emotional stimuli)

(2)Hypohidrosis and anhidrosis presents as dry and coarse skin with scaling, mild itching or fever Heat stroke--severe case Treatment-- cool bath, air conditioning, light clothing

Disorders of eccrine sweat glands (3) Miliaria Miliaria crystallina: small crystal clear vesicle-- the level of block of the sweat duct is within the stratum corneum

Disorders of hair alopecia areata male pattern baldness

Alopecia Areata General character: ＊ atopy and autoimmune mechanism ＊ offen affect children and young adults ★ one or more well-demarcated bald areas ★the affected scalp is normal ★ self-limited disease （hair regrowth）

Alopecia areata Treatment: topical minoxidil (stimulates the hair follicles, 2%-5%) topical steroids

Alopecia androgenetica / Male pattern baldness/ female baldness

Male pattern baldness ＊the main area of loss in men is the crown,with some frontal recession ＊commonly in men, occasionally in postmenopausal women ＊ increase with age ＊an androgen dependent inherited disorder

Excessive growth of hair hirsutism hypertrichosis

Hirsutism ＊an excessive growth of body hair in women or children in an androgen induced hair pattern (upper lip, chin, sideburn areas, neck, chest, et al)

Hypertrichosis a generalized or localized pattern of non-androgen-dependant excessive hair growth in a male or female without evidence of masculinism or menstrual abnormality

Question What are the main four factors which contribute to development of the Acne ?