Derm Lecture 2 disease/conditions only

Nevi (Benign Moles): Underlying mechanism

Noncancerous proliferations of melanocytes

Nevi: Clinical presentation

Symmetric, uniform color, smooth borders; usually < 6 mm

Nevi: First-line management

Observation; no treatment required

Nevi: Maturation stages

Mature from Junctional (flat) to Compound (raised) to Intradermal (dome-shaped)

Seborrheic Keratosis: Definition

Benign proliferation of epidermal keratinocytes

Seborrheic Keratosis: Hallmark appearance

"Stuck-on," waxy, or verrucous papules that are well-demarcated

Seborrheic Keratosis: Distribution

Clinical inspection reveals these lesions spare the palms and soles

Seborrheic Keratosis: Standard first-line approach

Reassurance

Seborrheic Keratosis: Removal methods

Cryotherapy, curettage, or shave removal

Seborrheic Keratosis: Patient population

Commonly seen in older adults; waxy appearance is a hallmark

Dermatofibroma: Definition

Benign fibrous skin lesion often following minor trauma

Dermatofibroma: Presentation

Firm papule or nodule < 1 cm; pink, tan, or brown; common on lower extremities

Dermatofibroma: Diagnostic sign

Positive "dimple sign" with lateral compression

Dermatofibroma: Triggers

Often follows insect bites or shaving trauma

Skin Tags (Acrochordons): Description

Soft, pedunculated ("on a stalk") polyps typically 1–10 mm in size

Skin Tags: Common locations

Frequently found on the neck, axillae, eyelids, and groin

Skin Tags: Associated conditions

Associated with obesity, insulin resistance, and pregnancy

Keratoacanthoma: Classification

Rapidly growing variant of cutaneous Squamous Cell Carcinoma (SCC)

Keratoacanthoma: Physical appearance

Firm, dome-shaped nodule with a central keratin crater

Keratoacanthoma: Preferred diagnostic method

Excisional biopsy is preferred to exclude invasive SCC

Keratoacanthoma: Treatment principle

Treat as cutaneous SCC until proven otherwise

Keratoacanthoma: Growth hallmark

Known for a "volcano-like" appearance that grows over weeks

Freckles (Ephelides): Characteristics

Flat, brown macules (< 3 mm) that increase with sun and fade in winter

Freckles: Primary treatment

Sun protection; lesions often become less noticeable with age

Cherry Angioma: Definition

Benign vascular proliferation of capillaries

Cherry Angioma: Physical description

Bright red to violaceous dome-shaped papules; 1–5 mm

Cherry Angioma: Clinical pearl

Increase in number with age and may bleed if traumatized

Pyogenic Granuloma: Description

Bright red, friable papule that bleeds easily with minimal trauma

Pyogenic Granuloma: Growth rate

Rapid growth over days to weeks; often follows minor trauma

Pyogenic Granuloma: First-line treatment

Shave excision with electrocautery or curettage

Describe Infantile Hemangioma: "Strawberry" type

Bright red and raised vascular tumor

Infantile Hemangioma: Timing

Appears within the first weeks of life; most significantly regress by school age

Infantile Hemangioma: Medical treatment

Oral propranolol is used for problematic lesions

Actinic Keratosis: Mechanism

Premalignant atypical keratinocyte proliferation

Actinic Keratosis: Texture hallmark

Rough, gritty ("sandpaper") erythematous papule with adherent scale

Actinic Keratosis: Significance

Serves as a marker of cumulative sun damage and can progress to invasive SCC

Actinic Keratosis: Isolated lesion treatment

Cryotherapy

Actinic Keratosis: Field treatment

Topical 5-FU or Imiquimod

Dysplastic Nevi: Features

Often > 6 mm; asymmetric with irregular borders and variegated pigmentation

Dysplastic Nevi: Risk factor

These lesions are markers of an increased risk for melanoma

Basal Cell Carcinoma (BCC): Classic presentation

Pearly, translucent papule with rolled borders and telangiectasias

Basal Cell Carcinoma (BCC): "Rodent ulcer"

A central ulceration often found in BCC lesions

Basal Cell Carcinoma (BCC): High-risk treatment

Mohs micrographic surgery

Basal Cell Carcinoma (BCC): Metastatic risk

Extremely rare, occurring in less than 0.1% of cases

Squamous Cell Carcinoma (SCC): Appearance

Firm, erythematous, hyperkeratotic (thick scale) nodule; often painful

Squamous Cell Carcinoma (SCC): Aggressiveness

More aggressive than BCC; can metastasize in 2–5% of cases

Squamous Cell Carcinoma (SCC): First-line treatment

Surgical excision

Malignant Melanoma: ABCDE - Asymmetry

One half of the lesion does not match the other

Malignant Melanoma: ABCDE - Border

Irregular, notched, or blurred borders

Malignant Melanoma: ABCDE - Color

Variegated pigmentation including brown, black, red, or blue

Malignant Melanoma: ABCDE - Diameter

Usually greater than 6 mm

Malignant Melanoma: ABCDE - Evolution

Any change in size, shape, or color

Malignant Melanoma: Prognostic factor

Breslow thickness (depth) is the most important factor for prognosis

Malignant Melanoma: Preferred biopsy

Excisional biopsy is the preferred method

Kaposi’s Sarcoma: Underlying cause

Vascular tumor caused by HHV-8

Kaposi’s Sarcoma: Appearance

Multiple violaceous (purple-red), non-blanching macules, plaques, or nodules

Kaposi’s Sarcoma: Primary management

Optimize immune function (e.g., ART for HIV/AIDS patients)

Herpes I & II: Presentation

Clusters of painful vesicles on an erythematous base; rupture to form ulcers

Herpes I & II: First-line treatment

Antivirals such as Acyclovir, Valacyclovir, or Famciclovir

Herpes I & II: Triggers

Stress, sun exposure, fever, and illness

Varicella (Chickenpox): Clinical description

"Dew Drop on a Rose Petal" appearance

Varicella: Lesion stages

Successive crops of lesions in all stages simultaneously

Warts (HPV): Physical description

Hyperkeratotic, rough papules with a "cauliflower" surface

Warts (HPV): Diagnostic pearl

Paring the lesion reveals tiny black dots

Warts: First-line treatments

Salicylic acid or cryotherapy

Molluscum Contagiosum: Appearance

2–5 mm smooth, flesh-colored, dome-shaped papules with central umbilication

Molluscum Contagiosum: Natural history

Spontaneous regression is common over months to years

Molluscum Contagiosum: Contagion

Highly contagious via skin contact or shared equipment

Pilonidal Disease: Physical hallmarks

Midline pits and a painful, fluctuant, erythematous mass in the gluteal cleft

Pilonidal Disease: Risk factors

Male, age 15–30, obesity, and prolonged sitting

Pilonidal Disease: Acute treatment

Incision and Drainage

Trichotillomania: Presentation

Irregular patches of hair loss with broken hairs of varying lengths

Trichotillomania: First-line treatment

Cognitive Behavioral Therapy (habit reversal training)

Telogen Effluvium: Definition

Rapid hair loss occurring 2–3 months after physiologic stress

Telogen Effluvium: Clinical presentation

Diffuse thinning where hair follicles remain intact

Telogen Effluvium: Triggers

Triggered by childbirth, severe illness, surgery, or rapid weight loss

Traction Alopecia: Mechanism

Chronic tension on hair follicles from tight hairstyles

Traction Alopecia: Location

Hair loss typically occurs at the frontal or temporal scalp

Traction Alopecia: Reversibility

Reversible if hair practices are changed early

Scarring Alopecia: Key feature

Destruction of hair follicles leading to permanent hair loss

Androgenetic Alopecia: Male pattern

Receding hairline and thinning at the vertex

Androgenetic Alopecia: Female pattern

Diffuse thinning at the crown of the head

Androgenetic Alopecia: First-line treatment

Topical minoxidil

Androgenetic Alopecia: Male-only treatment

Oral finasteride

Alopecia Areata: Clinical hallmarks

Smooth, well-demarcated round patches with "exclamation mark" hairs

Alopecia Areata: Mechanism

Autoimmune T-cell attack on hair follicles

Alopecia Areata: Nail findings

Nail pitting and ridging are commonly seen

Rosacea: Symptoms

Facial flushing and persistent central erythema without comedones

Rosacea: Triggers

Heat, alcohol, spicy foods, and sunlight

Rosacea: Mild treatment

Topical metronidazole

Acne Vulgaris: Pathophysiology

Chronic inflammation of the pilosebaceous unit caused by follicular plugging

Acne Vulgaris: Hallmark lesions

Open comedones (blackheads) and closed comedones (whiteheads)

Acne Vulgaris: Mild treatment

Benzoyl peroxide and/or topical retinoid

Acne Vulgaris: Severe treatment

Oral Isotretinoin (Accutane)

Perioral Dermatitis: Presentation

Small erythematous papules around the mouth or eyes sparing the vermilion border

Perioral Dermatitis: First-line treatment

"Zero therapy" (avoiding all cosmetics and steroids)

Epidermal Inclusion Cyst: Description

Firm, movable dermal nodule with a characteristic central punctum

Epidermal Inclusion Cyst: Content

Contains foul-smelling cheesy keratin

Epidermal Inclusion Cyst: Definitive treatment

Complete surgical excision

Flat, pink-red capillary malformation. Common on glabella, eyelids, nape, blanches with pressure. Usually fades 1-2 years

Nevus simplex