Derm III

Dermatology Course Notes by Tonya Kerker PA-C

Overview

  • Course: Derm III - Clinical Medicine I

  • Instructor: Tonya Kerker PA-C

Review Questions

  • What are the two types of hair loss?

  • What is the medical term for male pattern baldness?

  • Types of hair loss:

    • Postpartum states

    • After chemotherapy

    • Due to autoimmune diseases

    • Due to severe chemical burns

  • Treatment for:

    • Acute paronychia

    • Chronic paronychia

    • Onychomycosis of the nails

  • Reasons to transfer or consult with a burn unit:

    • Three specific reasons mentioned

  • What percentage of Body Surface Area (BSA) results in metabolic derangements?

Objectives

  1. Identify:

    • Pathology

    • Epidemiology

    • Signs/Symptoms

    • Differential Diagnosis

    • Treatment Options

    • Prognosis of dermatologic exanthems

  2. Discuss:

    • Pathology

    • Epidemiology

    • Signs/Symptoms

    • Differential Diagnosis

    • Treatment Options

    • Prognosis of acneiform dermatologic conditions

  3. Identify:

    • Pathology

    • Epidemiology

    • Signs/Symptoms

    • Differential Diagnosis

    • Treatment Options

    • Prognosis of papulosquamous, desquamating, and vesiculobullous conditions

Blueprint Topics

  • Exanthems

    • Erythema infectiosum

    • Hand-foot-and-mouth disease

    • Measles

    • Rubella

    • Roseola infantum

  • Acneiform eruptions

    • Acne vulgaris

    • Folliculitis

    • Rosacea

    • Perioral dermatitis

  • Papulosquamous disorders

    • Contact dermatitis

    • Drug eruptions

    • Eczema

    • Lichen planus

    • Pityriasis rosea

    • Psoriasis

    • Seborrheic dermatitis

  • Desquamation

  • Erythema multiforme

  • Stevens-Johnson syndrome

  • Toxic epidermal necrolysis

  • Vesiculobullous diseases

    • Pemphigoid

    • Pemphigus

Exanthems

  • Erythema Infectiosum (Fifth Disease)

    • AKA “slapped cheek syndrome”

    • Typically benign childhood viral illness.

    • 70% of cases occur in children aged 5-15 years.

    • Epidemiology: More common in outbreaks than sporadic cases; peaks in winter and early spring.

    • Etiology: Human parvovirus B19

    • Transmission: Via respiratory secretions.

    • Viremia occurs 5-10 days after exposure lasts about 5 days.

Clinical Presentation

  • Prodromal symptoms:

    • Begin 1 week after exposure and last 2-3 days

    • Headache

    • Fever

    • Sore throat

    • Pruritus

    • Coryza

    • Abdominal pain

    • Arthralgias (more common in adults)

  • Some patients are asymptomatic during this time.

  • Followed by:

    • Phase 1: Slapped-cheek appearance, fades over 2-4 days.

    • Phase 2: Erythematous maculopapular rash appears 1-4 days later; fades into a lacelike reticular pattern.

    • Phase 3: Recurrent clearings and recurrences may occur due to stimuli (exercise, irritation, stress, overheating from sunlight/hot baths).

Diagnosis & Treatment

  • Diagnosis: Clinical based on signs and symptoms.

  • Treatment:

    • Primarily supportive and symptomatic; no specific therapy.

    • Symptomatic therapy may be indicated for:

    • Arthralgias

    • Arthritis

    • Pruritus

  • Prevention: Infection control measures, including good hand hygiene and responsible behaviors during illness.

Hand-Foot-and-Mouth Disease (HFMD)

  • Clinical Syndrome: Characterized by oral enanthem and macular, maculopapular, or vesicular rash on the hands and feet.

  • Epidemiology: Worldwide, with common outbreaks in daycare settings.

    • Most cases occur in infants and children under 5-7 years old.

  • Etiology: Coxsackievirus.

  • Transmission: Primarily through GI (fecal-oral route) and respiratory routes.

  • Incubation Period: 3-5 days with viral shedding lasting up to 10 weeks via feces and 30 days via respiratory route.

    • HFMD is generally mild; resolution typically occurs within 7-10 days.

Clinical Presentation

  • Complaints:

    • Mouth/throat pain (verbal children) or refusal to eat (nonverbal children).

    • Fever usually below 38.3°C (101°F).

  • Oral Enanthem:

    • Begins as erythematous macules progressing to vesicles that rupture into ulcers.

  • Exanthem:

    • Macular, maculopapular, or vesicular; usually non-painful.

    • Involves hands, feet, buttocks, legs, and arms.

Diagnosis & Treatment

  • Diagnosis: Clinical, based on appearance and typical location of symptoms.

  • Treatment: Supportive care,

    • Ensure hydration, pain management with Tylenol/Ibuprofen.

    • Topical therapies are not routinely recommended.

  • Prevention: Hand hygiene, exclusion measures in childcare settings.

Measles (Rubeola)

  • Highly contagious viral infection occurring worldwide.

    • Approximately 90% of susceptible individuals will develop measles following exposure.

  • Epidemiology: Leading cause of mortality among children ≤5 years; substantial fatality rate pre-vaccine era.

  • Etiology: Measles virus.

  • Contagiousness: From 5 days before rash onset to 4 days after.

  • Incubation Period: 6-21 days (median 13 days).

Clinical Presentation

  • Prodrome lasts 2-4 days:

    • High fever

    • Malaise

    • Anorexia, followed by:

    • Conjunctivitis

    • Coryza

    • Cough

  • Koplik Spots: Tiny white lesions inside the mouth appear 48 hours before the rash.

  • Exanthem:

    • Begins 2-4 days after fever onset. Erythematous, maculopapular rash starting on the face, spreading downwards to the body.

Complications

  • Occur in about 30% of cases:

    • Diarrhea: most common (8%)

    • Pneumonia: leading cause of measles-related death in children (6%)

    • Encephalitis: occurs in 1 in 1000 cases.

    • Neurodevelopmental sequelae in about 25% of cases.

Diagnosis & Treatment

  • Diagnosis: Serologic testing for measles IgM antibody, especially in unimmunized individuals.

  • Treatment: Supportive; vitamin A supplementation for severe cases may help reduce complications.

  • Prevention: Vaccination is critical to achieving herd immunity at levels above 95%.

Rubella (German Measles)

  • Vaccine-preventable viral infection; primarily mild but can cause serious fetal defects if contracted during pregnancy.

  • Epidemiology: Declared eliminated in the United States in 2004; 100,000 births with congenital rubella syndrome estimated annually worldwide.

  • Transmission: Inhalation of infectious aerosols.

  • Incubation Period: 14-18 days, infectious from 1 week before to 2 weeks after rash appearance.

Clinical Presentation

  • Maculopapular Rash: Generalized, starting on the face, spreading downwards. Generally mild systemic symptoms, lymphadenopathy, and low-grade fever may occur.

Diagnosis & Treatment

  • Diagnosis: Clinical based on symptoms and known exposure.

  • Treatment: Supportive care; vaccination for prevention.

Roseola Infantum (Sixth Disease)

  • Etiology: Human herpesvirus 6 (HHV-6).

  • Epidemiology: Affects mainly children ages 7 to 13 months; 90% of cases occur in children <2 years.

  • Transmission: Respiratory droplets.

  • Incubation Period: 9-10 days.

Clinical Presentation

  • Febrile Phase: High fever lasting 3-5 days, followed by rash as fever resolves.

  • Rash: Blanching macular or maculopapular, starts on the neck and trunk, spreads to extremities.

  • Diagnosis: Clinical.

Treatment

  • Generally self-limiting; treatment is supportive.

Acneiform Eruptions

  • Conditions include:

    • Acne vulgaris

    • Folliculitis

    • Rosacea

    • Perioral dermatitis

Acne Vulgaris

  • Definition: Common skin disorder with chronic papules, pustules, nodules on face, neck, trunk, shoulders.

  • Epidemiology: 35-90% prevalence, especially in adolescents.

  • Etiology: Multifactorial; hormones, medications, diet, stress, genetic factors, cosmetic use, etc.

Pathogenesis

  • Four major contributors:

    1. Follicular duct hyperkeratinization.

    2. Increased sebum production.

    3. Proliferation of acne bacillus.

    4. Resulting inflammation.

Clinical Presentation

  • Lesions:

    • Non-inflammatory: open and closed comedones.

    • Inflammatory: pustules, papules, nodules, and cysts.

Treatment
Pre-Treatment Assessment

  • Assess lesion types, severity, presence of complications, and contributing factors.

Categorization of Severity

  • Mild: Scattered, small lesions, no scarring.

  • Moderate to Severe: More extensive involvement, potential for scarring.

General Treatment Approach

  1. Patient Counseling: Educate on medication/cosmetic use, avoiding lesion manipulation, proper skin cleansing, and dietary recommendations.

  2. Choosing Medications: Topical retinoids, benzoyl peroxide, topical antibiotics (e.g., clindamycin) for various lesion types.

  3. Systemic Treatments: For moderate-severe cases, incorporating antibiotics and antiandrogens where necessary.

Folliculitis

  • Definition: Inflammation of hair follicles.

  • Clinical Presentation: Papules or pustules on hair-bearing skin, may be bacterial (commonly Staph aureus).

  • Diagnosis: Clinical based on lesion location, morphology.

  • Treatment: Varies with severity; topical or systemic antibiotics for extensive cases.

Rosacea

  • Definition: A chronic skin disorder with skin and ocular manifestations.

  • Clinical Presentation: Erythematous papules, flushing, telangiectasias, with triggers including heat, spicy food.

  • Diagnosis: Clinical based on history and presentation.

  • Treatment: Depend on severity, generally includes avoidance of triggers, topical treatments, and systemic therapy for severe cases.

Perioral Dermatitis

  • Definition: Inflammatory papules around the mouth/eyes; associated with topical steroid use.

  • Clinical Presentation: Clustered, erythematous papules, possible stinging or burning.

  • Diagnosis: Clinical based on history and appearance.

  • Management: Withdrawal of topical steroids, possible pharmacologic therapy with topical antibiotics and reevaluation for improvement.

Papulosquamous Disorders

  • Focus on:

    • Contact dermatitis

    • Drug eruptions

    • Eczema (atopic dermatitis)

    • Lichen planus

    • Pityriasis rosea

    • Psoriasis

    • Seborrheic dermatitis

Contact Dermatitis

  • Types: Irritant vs Allergic.

    • Irritant: Burning, dryness, or stinging; allergic: delayed hypersensitivity.

  • Diagnosis/Treatment: Based on history and symptoms; management focuses on avoidance and topical therapies.

Eczema (Atopic Dermatitis)

  • Definition: Chronic inflammatory skin disease with pruritus and dry skin.

  • Epidemiology: 5-20% of children affected; higher prevalence in African Americans.

  • Clinical Presentation: Varies by age; common locations include flexural surfaces.

  • Diagnosis/Treatment: Clinical; topical therapies for treatment, education on skin care best practices.

Psoriasis

  • Definition: Common chronic inflammatory disease with various subtypes.

  • Clinical Features: Symmetrical plaques, typically on extensor surfaces and scalp; associated with comorbidities such as psoriatic arthritis.

  • Management: Based on severity, includes topical agents, phototherapy, systemic medications.

Seborrheic Dermatitis

  • Definition: Chronic, relapsing dermatitis due to Malassezia colonization.

  • Presentation: Erythematous plaques with greasy scale, commonly found on the scalp and face.

  • Treatment: Topical antifungals and steroids; goal of treatment is symptom reduction and visible clearance.

Drug Eruptions

  • Incidence/Presentation: Eruptions commonly occur within 1-4 weeks of new drug introduction; characterized often as morbilliform.

  • Management: Identification and cessation of the offending drug; symptomatic relief usually sufficient.

Desquamating Disorders

  • Focus on Erythema Multiforme, Stevens-Johnson Syndrome (SJS), and Toxic Epidermal Necrolysis (TEN).

  • Erythema Multiforme: Characterized by target lesions, often precipitated by infections, especially HSV.

  • SJS/TEN: Emergencies requiring immediate cessation of medication and support; SJS involves <10% BSA, TEN >30% BSA.

Management

  • During acute phases: fluid management, wound care, and identification of causative drugs are crucial.

Vesiculobullous Diseases

Pemphigus

  • Description: Autoimmune blistering disease.

  • Diagnosis/Treatment: Requires biopsy; often treated with systemic steroids and immunosuppressants.

Pemphigoid

  • Description: Autoimmune disease affecting basement membranes; manifests with tense blisters.

  • Diagnosis/Treatment: Similar to pemphigus, emphasizing supportive care and systemic steroids for widespread cases.

Final Notes

  • Stay updated, continue clinical practice education, and discuss any concerns with supervising dermatologists.

  • Utilize patient education resources for enhanced understanding of skin conditions.