Skin disorders Flashcards
How many grams of topical cream/ointment are needed for a single application to the hands, head, face, anogenital region?
2 g
How many grams of topical cream/ointment are needed for a single application to one arm, anterior or posterior trunk?
3 g
How many grams of topical cream/ointment are needed for a single application to one leg?
6 g
How many grams of topical cream/ointment are needed for a single application to the entire body?
30-60 g
How many grams of a topical cream/ointment can be expected in one fingertip unit (FTU)?
From very end of the finger to the first crease in the finger
0.5 g
Low potency topical corticosteroids (class V to VII)
- Hydrocortisone (0.5%, 1%, 2.5%)
- Desonide (0.05%)
- Triamcinolone (0.025%, 0.1%)
High potency topical corticosteroid (class II)
Betamethasone dipropionate 0.05%
Super high potency topical corticosteroid (class I)
- Clobetasol propionate 0.05%
- Halobetasol propionate 0.05%
True/false: Topical corticosteroids should not be used longer than 3 months to avoid adverse effects including SQ tissue atrophy
True
First generation vs second generation antihistamines
First generation → diphenhydramine (benadryl)
Second generation → loratidine (claritin), cetirizine (zyrtec), fexofenadine (allegra)
Precautions that should be taken when prescribing first generation antihistamines
Crosses the BBB → sedation
- Caution in geriatrics (drying of secretions, visual changes, urinary retention, used as sleep aid)
What is impetigo?
Contagious skin infection with typical presentation of purulent skin lesions
- Common in children 2-5 years old
- Causative agents: s. aureus, GAS
Impetigo clinical presentation
- Can be bullous or nonbullous
- Honey colored crusting with erythematous base
- Common on face and extremities
Impetigo treatment
- Usually resolves without treatment in 1-2 weeks
- Can consider topical antimicrobial therapy to minimize contagion → mupirocin (bactroban)
True/false: Children with impetigo should be kept out of school or daycare for 24 hours after initiation of antibiotic therapy, and family members should be checked for lesions
True
When can the provider consider using oral therapy for impetigo treatment?
Beta-lactamase (dicloxacillin, amoxicillin-clavulanate) or cephalosporin
- Patients with bullous impetigo
- Have numerous lesions
- Not responding or cannot tolerate topical agents
- During outbreaks
Mild acne classification
- Fewer than 20 comedones
- Fewer than 15 inflammatory lesions
- Total lesion count fewer than 30
Moderate acne classification
- 20-100 comedones
- 15-50 inflammatory lesions
- Total lesion count 30-125
True/false: During acne treatment, patient education should include that improvement will not be seen with medication until 2-4 weeks of therapy is completed
False - will take 4-6 weeks before improvement is seen
Examples of keratolytic/comedolytic agents used for acne treatment
- Tretinoin (Retin-A)
- Should be used with sunscreen due to photosensitivity
- Adapalene
- Tazarotene
Hormonal therapy for acne treatment
- COC pills → suppress ovarian androgen production
- Aldosterone antagonist (spironolactone) → reduces free testosterone
When is isotretinoin (accutane) therapy indicated for acne treatment?
For severe and/or cystic acne that does not respond to conventional therapy
Isotretinoin (accutane) considerations
- Teratogenic → use two forms of contraceptive, avoid sex 1 month after d/c
- Assess for depressed mood, SI
- Monitor for pseudotumor cerebri, hypertriglyceridemia, elevated hepatic enzymes, chelitis
Treatment recommendations for mild acne (comedonal, inflammatory, mixed lesions)
Benzoyl peroxide OR topical retinoid (tretinoin, adapalene, tazarotene)
Treatment recommendations for moderate acne (comedonal, inflammatory, mixed lesions)
Topical combination therapy:
- Benzoyl peroxide + topical antibiotic
- Benzoyl peroxide + retinoid
- Retinoid + benzoyl peroxide + topical antibiotic
Treatment recommendations for severe acne (inflammatory, mixed, and/or nodular lesions)
- Oral antibiotic + topical combination therapy:
- BP + topical antibiotic
- BP + retinoid
- BP + retinoid + topical antibiotic
- Oral isotretinoin
Antibiotic of choice for patients coming in with bite wounds
Amoxicillin with clavulanate
First degree burn classification
Superficial
- Red
- Somewhat painful
- Easily blanched
- Warm to touch
Second degree burn classification
Partial thickness
- Deeply red
- Blistered
- Swollen
- Hot to touch
- Raw
- Moist surface
- Very painful
Deep second degree burn classification
Deep partial thickness
- Involves deep layers of dermis
- Appears white
- Does not blanch
Third degree burn classification
Full thickness
- Whitish
- Charred or translucent
- Not painful
- Affected area lacks pinprick sensation
- Surrounded by painful first and second degree burns
Rule of nines for calculating total burn
Indications for referral to burn center for care
- Partial thickness burns >10% of total body surface area in adults or >5% for children
- Burns that involve the face, hands, feet, genitals, perineum, major joints, and/or circumferential
- Third degree burns in any age group
- Electrical burns including lightening
- Chemical burns
- Inhalation injury
- Burn injuries in patients with preexisting medical disorders that complicate management
- Burned children in hospitals with qualified personnel or equipment
- Burn injury in patients who will require special social, emotional, or rehab
Under what conditions can burns be treated outpatient?
Small (<10% of BSA), minor (second degree or lower) burns not involving high function areas and of minimal cosmetic consequence
What is atopic dermatitis?
Eczema
- Type I hypersensitivity reaction resulting from IgE antibodies occupying receptor sites on mast cells
Atopic dermatitis clinical presentation
- Itchiness
- Xerosis (dry skin)
- Lichenification (from rubbing or scratching)
- Eczematous lesions
- Any age → flexural surfaces; children → face and neck
Medications available for atopic dermatitis (eczema)
- Oral antihistamines for flare ups (oral hydroxyzine, doxepin)
- Intermediate potency topical corticosteroid
- Pimecrolimus and tacrolimus
- NOT for children younger than 2 years
Herpes zoster (shingles) prodrome symptoms
1-2 days before rash eruption
- Generalized body aches
- Itching, burning, painful sensation
Herpes zoster (shingles) clinical presentation
- Burning, throbbing, stabbing pain
- Intense itch
- Rash follows dermatome (doesn’t cross midline)
- Crusting lesions after 14-21 days as rash resolves
Herpes zoster (shingles) treatment
- Antivirals → acyclovir, valacyclovir, famciclovir
- Topical lidocaine
What is a complication of herpes zoster (shingles)?
Postherpetic neuralgia (PHN) → pain persisting at least one month after the rash has healed
What is onychomycosis?
Nail fungus → found on the toenails or fingernails
- Can involve the nail matrix, nail bed, and/or nail plate
Onychomycosis diagnostic testing
- Microscopic examination of nail scraping and KOH for hyphae
- Fungal culture
- PCR analysis to detect fungal DNA
Onychomycosis treatment
- Oral antifungals → itraconazole, terbinafine, fluconazole
- Pulse cycles
- Laser therapy
Scabies mode of transmission
Close personal, skin to skin contact
- Contact with used, unwashed bedding and clothing from affected person
Scabies clinical presentation
- Linear burrows
- Older adults → excoriated lesions on back
- Infants and young children → palms and soles
Scabies treatment
- Permethrin lotion → must be left on for 8-14 hours
- Oral antihistamines or low potency topical corticosteroids for itchiness
- Wash bedsheets and clothes in hot water, placed in dryer for a normal cycle, or in plastic storage bag for 1 week
What is psoriasis?
Chronic skin disorder caused by accelerated mitosis and rapid cell turnover leading to decreased maturation and keratinization
Psoriasis clinical presentation
- Extensor surfaces (elbows and knees), scalp
- Silvery scales
How to differentiate psoriatic arthritis from rheumatoid arthritis and gout?
- Negative rheumatoid factor
- ESR normal
- May have elevated uric acid
- Pencil-in-cup deformity and joint space narrowing in interphalangeal joints on x-ray
Psoriasis treatment
- First line → topical corticosteroids
- Tar preparations
- Referral to dermatologist for severe disease
What is seborrheic dermatitis?
Chronic, recurrent skin condition found in areas with a high concentration of sebaceous glands (scalp, eyelid margins, nasolabial folds, ears, upper trunk)
Seborrheic dermatitis clinical presentation
- Cradle cap in young children
- If mild → patchy scaling
- Scaling may present over red, inflamed skin with hypo pigmentation, oozing, crusting
- Moderate to severe → thick, adherent crusts
Seborrheic dermatitis (cradle cap) treatment
- Emollients (olive oil)
- Topical corticosteroids
Seborrheic dermatitis treatment in adults
- Topical antifungals (ketoconazole)
- Topical corticosteroids
- Cool tar shampoo
ABCDE of skin cancer screening (melanoma)
- A = asymmetric with non matching sides
- B = borders are irregular
- C = color is not uniform
- D = diameter >6 mm (size of pencil eraser)
- E = evolving lesion
PUT ON mnemonic for basal cell carcinoma screening
- P = pearly papule
- U = ulcerating
- T = telangiectasia
- O = on the face, scalp, pinnae
- N = nodules (slow growing)
NO SUN mnemonic for squamous cell carcinoma screening
- N = nodular
- O = opaque
- S = sun exposed areas
- U = ulcerating
- N = non distinct borders
What skin lesion can progress to SCC?
Actinic keratosis = UV induced skin lesions
- Small rough patches, sandpaper like quality
- Become large, red, and scaly over time
Treatment for actinic keratoses
- Cryotherapy
- 1-5% fluorouracil cream
True/false: “Watch and wait” therapy for warts is appropriate because most will self resolve within 12-24 hours
True
Cellulitis clinical presentation
- Warm, red, painful edematous area
- Sharply demarcated borders
- Local lymphangitis and lymphadenitis
Cellulitis treatment
- Dicloxacillin
- Cephalexin
- Azithromycin (PCN allergy)
Abscess treatment
- If afebrile and <5 cm in diameter = I&D, warm soaks (consider culture)
- If >5 cm = add antimicrobial therapy
- TMP-SMX (bactrim), doxycycline, clindamycin
Risk factors for angular cheilitis
Loss of vertical facial dimension (loss of teeth) allowing for candida growth at skin folds
Angular cheilitis clinical presentation
- Erythema with painful cracking, scaling, ulceration at corners of mouth
- Intermittent bleeding
- Sudden onset
Angular cheilitis treatment
Topical antifungals (nystatin, miconazole)
- Oral antifungals if topical therapy didn’t work
- Keep area moist with moisturizer for prevention
How long does a tick need to feed on a human host for before spirochete transmission?
For at least 24 hours
Stage 1 of Lyme disease
- Early localized disease
- Mild flu-like illness
- Single annular lesion with central clearing (erythema migrans)
- NO pain or itchiness
Stage 2 of Lyme disease
- Early disseminated infection (months later)
- Rash reappears with multiple lesions
- Arthralgia, myalgia
- Headache
- Fatigue
- Cardiac manifestations
- Neurologic findings (Bell’s palsy)
Stage 3 of Lyme disease
- Late persistent infection (1 year after initial exposure)
- MSK symptoms persist (joint pain, arthritis)
- Neuropsychiatric symptoms (memory problems, depression, neuropathy)
Lyme disease diagnostic testing
Serum testing for b burgdorferi by enzyme linked immunosorbent assay and confirmatory Western blot for IgM antibodies
What considerations should be made about diagnostic testing for Lyme disease in relation to IgM and IgG levels?
IgM antibodies decline after 4-6 months of illness
IgG is noted about 6-8 weeks after onset of symptoms (persists at low levels despite treatment)
Lyme disease treatment
Doxycycline for 14-21 days for earlier disease and up to 28 days for more advanced disease
True/false: Bed bug bites appear in a “breakfast, lunch, and dinner” pattern
True - Parasite will bite one location, then move laterally to bite again, and repeat the action for the third bite
Bed bugs clinical presentation
- Red with darker red spot int he middle
- Itchy
- Arranged in a rough line or in a cluster
- Located on face, neck, arms, hands
Bed bugs treatment
Usually not required unless there is secondary infection
- Antiseptic lotion or topical antibiotic
- Topical corticosteroids or oral antihistamines for itch
Professional extermination
Possible triggers for rosacea
- UV/sunlight exposure
- Hot/cold exposure
- Exercise
- Stress
- Coffee
- Chocolate, caffeine
- Alcohol
- Spicy foods
- Cosmetic products and medications
What are the four types of rosacea?
- Erythematotelangiectatic
- Papulopustular
- Phymatous
- Ocular
Rosacea treatment
- Avoid triggers
- Non ablative laser therapy, mechanical dermabrasion, laser peel, surgical shave
- Metronidazole gel
- Acne products
- Oral antimicrobial for ocular rosacea
