Derm 1

Dermatology 1

•  The course is Dermatology 1, taught by Professor Jacobus, MSBS, PA-C.
•  The course is offered at South College.

Topics

•  Papulo-squamous diseases: Dermatitis, eczema, drug eruptions, lichen planus, pityriasis rosea, and psoriasis.
•  Desquamation: Erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis.
•  Vesicular bullae: Pemphigoid and pemphigus.
•  Acneiform lesions: Acne vulgaris, rosacea, and folliculitis.

Instructional Objectives

•  Identify and describe the etiology, epidemiology, clinical features, differential diagnosis, and management of selected skin disorders.
•  Identify and accurately describe skin lesions using standard terms:
  • Number: single, multiple
  • Pigmentation/color: white, flesh-colored, pink, pearly, erythematous, tan-brown, salmon, black, purple, violaceous, and yellow
  • Shape and arrangement: annular, round/discoid, linear, oval, iris/target, zosteriform, serpiginous, stellate, reticulate, and morbilliform
  • Texture: consistency, mobility, temperature, tenderness, depth
  • Borders/margins: well-defined, ill-defined
  • Type: Primary lesions (macule, tumor, patch, wheal, papule, vesicle, plaque, bulla, nodule, pustule, cyst, and telangiectasia) or secondary lesions (crust, fissure, scale, ulcer, lichenified, keloid, erosion, hypertrophic scar, atrophy, and excoriation)
  • Arrangement/location/distribution: localized, regional, and generalized
  • Associated changes

Skin layers

•  The layers of the skin include the epidermis, dermis, and subcutaneous tissue.
•  Epidermal layers include the stratum corneum, granular layer, spinous layer, and basal layer.

Skin cell formation

•  Keratinocytes divide in the deepest (basal) layer
•  Cells move up the dermis, changing shape and composition
•  Cells secrete keratin proteins and lipids to form a protective matrix
•  Outermost skin cells die and shed.

Skin Exam

•  Be thorough; examine patients in gowns.
•  Use good lighting; consider magnification.
•  Check scalp, palms, soles, and nails.
•  Document any findings in detail, photograph, and monitor changes over time.

Approach to Diagnosis

•  Use the CLAMPS TN method: color, location/distribution, arrangement, margination, palpation, shape, type, and number.

Types of Skin Lesions (examples)

•  Crust
•  Cyst
•  Macule
•  Papule
•  Pustule
•  Ulcer
•  Vesicle
•  Wheal

Macule

•  Non-palpable
•  <1 cm diameter
•  Varied pigmentation from surrounding skin
•  No elevation or depression
•  Patch: macule > 1 cm diameter

Papule

•  Palpable
•  <1 cm diameter
•  Isolated or grouped
•  Pustule: small, circumscribed papule containing purulent material

Pustule

•  Circumscribed superficial cavity with purulent exudate.
•  Exudate can be white, yellow, greenish-yellow, or hemorrhagic.

Plaque

•  Plateau-like elevation
•  Lichenification - less defined large plaque (thickened, rough skin)
•  Patch – flat or barely elevated plaque

Nodule

•  Palpable, solid, fatty or cystic
•  Round or ellipsoidal
•  Larger than a papule
•  Tumor: nodule > 2 cm

Wheal

•  Irregularly-shaped, elevated, edematous
•  Erythematous or paler than surrounding skin
•  Well-demarcated borders
•  Disappears within 24-48 hours

Vesicle/Bulla

•  Blister
•  Vesicle <0.5cm; Bulla >0.5 cm
•  Well-defined
•  Thin roof
•  Serum and blood

Secondary Skin Lesions

•  Crust-dried serum, blood, or exudate
•  Scales-flakes
•  Erosion - epidermis defect (heals without scar)
•  Ulcer - defect in dermis or deeper (heals with scar)
•  Scar - fibrous tissue replacement
•  Atrophy - diminution of some or all layers of skin

History

• Demographics: age, race, sex, occupation, hobbies.
• Chemical/toxin exposure?
• Constitutional symptoms (acute vs chronic).
• History of skin lesions - OLD CARTS.

HX of Skin Lesion (OLD CARTS)

• When did lesion appear (first noticed)?
• Where did lesion appear (site of onset)?
• Does it come and go, or is it constant?
• Does it itch, hurt, or bleed?
• How has it spread (pattern/evolution)?
• How have individual lesions changed?
• What are provocative factors?
• What are previous treatments (topical, systemic)?

Papulosquamous Disease

• Eczema/ Dermatitis
• Drug eruptions
• Lichen planus
• Pityriasis rosea
• Psoriasis

Eczema/Dermatitis

• Dyshidrotic eczema
• Lichen simplex chronicus
• Nummular eczema
• Contact dermatitis
• Stasis dermatitis
• Atopic dermatitis
• Seborrheic dermatitis
• Perioral dermatitis

Desquamation

• Erythema multiforme

• Stevens-Johnson Syndrome (SJS)

• Toxic Epidermal Necrolysis (TEN)

• Erythema multiforme - presentation, history taking, target lesions

• Stevens-Johnson Syndrome (SJS)/Toxic Epidermal Necrolysis (TEN) – acute, life-threatening mucocutaneous reaction, necrosis & detachment of epidermis, differentiating SJS from TEN, rare, present, idiopathic or drug-induced, higher incidence in HIV & active cancer, F>M.

• Nikolsky sign-ability of sloughing to expand.

Vesiculobullous Disease

• Bullous pemhigoid- autoimmune, elderly patients, large, tense bullae

• Pemphigus- chronic or acute, bullous autoimmune disease, adults 40-60, predilection scalp, face, chest, axillae, groin, umbilicus. painful. PE- vesicles and bullae, easily rupture, flaccid and weeping, Nikolsky sign

• Acne & Related Disorders - acne vulgaris, rosacea, hidradenitis suppurativa

• Acne vulgaris - inflammation of pilosebaceous units, comes (open = blackheads, closed= whiteheads) ,can result in pits, depressions, scars or hyperpigmentation, more severe in males than females;less often in Asians; cystic acne can be familial.

• Factors in pathogenesis- follicular keratinization, androgens, Propionibacterium acnes

• Contributing factors - meds (lithium, isoniazid), steroids, OCP, androgens; stress; occlusion/pressure; cosmetics; pomade; sweat, worse in winter, comedones necessary diagnosis; labs- none, course clears by early 20's, flares with winter or menses- treatment, removal of plugs, topical antibiotics, topical retinoids; combination therapy works best.

• Treatment- moderate: same + PO antibiotics (minocycline, doxycycline, tapered to 50mg/d as acne lessens.

Rosacea

• Chronic inflammation of facial pilosebaceous units. • 30-50 y/o, F>M. • Episodic erythema, flushing & blushing, stages I, II, & III, persistent erythema, telangiectasias, papules, tiny pustules, nodules. • Note, no comedones • Triggered by hot liquids, spicy foods, alcohol/wine, aged cheese, exposure to sun & heat, stress • Duration: days, weeks, months • Late stage: rhinophyma • Treatment: reduce or eliminate alcohol/caffeine, topical antibiotics, PO antibiotics better than topical, PO isotretinoin for severe disease, surgery for rhinophyma/telangiectasias (lasers)

Folliculitis

• Inflammation or infection of superficial hair follicles. • Perifollicular papules and/or pustules with surrounding erythema; hair bearing skin; often pruritic • More common in males • Risk factors: prolonged antibiotic use, topical corticosteroids, hot tubs • Etiology: most common staph aureus; hot tub-->> pseudomonas auruginosa. •Treatment: Benzoyl peroxide wash (bleaches) topical mupirocin, clindamycin, erythromycin. If no improvement -- >PO Cephalexin.

Hidradenitis Suppurativa

• Chronic, suppurative • Apocrine gland skin. • Axillae, inguinocrural, anogenital, inframammary, rarely scalp • F (axillae)>M (anogenital) • FHx: NC acne & HS • Unknown etiology • Risk factors: obesity, smoking, genetic predisp. to acne. • Lesions: tender open & double comedones, red nodules/abscesses, sinus tracts, “bridge” scars, hypertrophic & keloidal scars, contractures. • Pathogenesis: follicle plugging > dilated follicle & apocrine duct inflammation > bacterial growth > extension > ulceration, fibrosis, sinus tracts > scarring. • Treatment (combination): intralesional steroids, then I&D abscess, prednisone for severe pain, & inflammation, surgery, PO antibiotics, Isotretinoin, adalimumab