Wright - Acne, Fungal, Viral Infections Flashcards
What are the 4 key factors in acne pathogenesis?
- Sebaceous gland hyperplasia
- Abnormal follicular desquamation: dead skin cell buildup at opening
- Propionibacterium acnes colonization
- Inflammation
What is this?
- Microcomedo:
1. Non-inflammatory comedones: blackhead (open) and whitehead (closed)
2. Inflammatory lesions: papules, pustules, nodules, cysts
How do you assess acne patient?
No consensus, but combine lesion counting with global assessment of severity
What are the topical and systemic acne treatments?
- Topical:
1. OTC: benzoyl peroxide, salicylic acid -> for very mild acne (sal acid less effective)
2. Prescription: antimicrobials, retinoids, combos - Systemic:
1. ABs, oral contraceptives, isotretinoin (acutane)
Benzoyl peroxide
- MOA: kills P. acnes
1. Mild comedolytic
2. Mild anti-inflammatory - Limits development of P. acnes AB resistance
- Combine with retinoid to increase efficacy
- No resistance reported
- Generally recognized as safe (GRASE) by FDA: AEs include irritation, bleaching, allergic contact dermatitis (1:500; variety of formulations)
What topical ABs are used to treat acne?
-
Clindamycin, erythromycin: antibac, anti-inflam
1. AEs: irritation, colitis (colon inflammation) reported with clindamycin (not a high risk) - NOT recommended as monotherapy: slow onset, resistance, and NOT comedolytic
1. Add topical benzoyl peroxide (BP), or use combo product: usually pretty easy to get, and covered by insurance - Really need to target comedone plug above all else
Topical retinoids
- Adapalene, Tretinoin, Tazarotene (pregnancy X)
- MOA: normalize follicular desquamation (comedolytic), anti-inflammatory, and enhance penetration of other compounds
- Indications: FIRST-LINE tx for all types of acne
1. Preferred for maintenance therapy - Side Effects: local irritation
- Can also help with wrinkles
What are the pros and cons of retinoid combo products?
- Some combo products w/AB or BP
- Pros: once a day (compliance)
- Cons: fixed retinoid (low concentration) and $$$$
When are systemic ABs given for acne?
- Mod-severe inflammatory (most not FDA approved for acne -> only Minocycline)
1. On these for several months - MOA: antibacterial, anti-inflammatory -> do NOT have comedolytic effects
- Goal is maintenance w/topical
- Preferred oral ABs (pts >=8): Tetracycline, Doxycycline, Minocycline
1. Less commonly Erythromycin/Bactrim
What are the AE’s with the systemic ABs?
- Generally well-tolerated: recommend taking with food (not dairy products bc can affect absorption)
- Severe AEs (uncommon):
1. Tetracycline: GI upset, teeth staining (<8 yr)
2. Doxycycline: photosensitivity, esophagitis (drink water)
3. Minocycline: dyspigmentation, lupus-like rxn, pseudomotor cerebri, SJS, DHS (drug hypersensitivity syndrome)
4. Erythromycin: GI sensitivity
Oral contraceptives for acne
- Females w/mod-severe inflam/mixed acne, esp. if flare with periods
- Anti-androgen effects suppress sebum production
What are the indications for Isotretinoin?
- Used to be called acutane (oral)
- Severe
- Scarring
- Refractory
- Very rarely start w/this -> most severe cases only
What is the MOA of the oral retinoids?
- Target all 4 factors of acne pathogenesis:
1. DEC size/activity of sebaceous glands -> reduces sebum production by >90%
2. Normalize follicular keratinization, preventing new comedones
3. Inhibit P. acnes
4. Anti-inflammatory
What are the common AEs of the oral retinoids? Serious AEs?
- Common: dry lips, skin, and eyes, nosebleeds, mild headaches, muscle aches, backaches
- Serious: TERATOGENIC -> iPledge
1. Depression, suicidal ideation (no causal relationship established)
2. Skeletal changes: more concerning for younger pts (fractures, hyperostosis, epiphyseal closure)
3. IBD: data conflicting (UC > CD)
What is the simple treatment algorithm for acne?
- Mild comedonal: topical retinoid
- Mild inflammatory/mixed: topical retinoid + topical antimicrobial
- Moderate inflammatory/mixed: topical retinoid + topical antimicrobial + oral antimicrobial
- Severe inflammatory:
1. Minimal scarring: topical retinoid + topical antimicrobial + oral antimicrobial
2. Scarring or multiple treatment failures: Isotretinoin
What is this? How would you treat it?
- Mild-mod comedonal acne
- Topical retinoid
What is this? How would you treat it?
- Mild mixed acne
- Topical retinoid + topical AB
What is this? How would you treat it?
- Moderate mixed acne
- Topical retinoid + topical AB + oral AB
What is this? How would you treat it?
- Severe mixed acne
- Minimal scarring: topical retinoid + topical AB + oral AB
- More severe scarring: Isotretinoid (have to come in monthly for 6 to 9 months)
What basic skin care should people with acne do?
- Gentle cleansing 1-2 times a day with mild, fragrance-free cleanser
- Oil-free moisturizer with SPF 30+ bid and prn
- Avoid OTC acne washes and topicals because too irritating/drying
What are some common acne myths? Are they true?
- Acne is NOT caused by poor hygiene or dirt
- Diet controversial:
1. High glycemic index diet may lead to hyperinsulinemia and stimulate androgen synthesis (relationship to METABOLIC SYNDROME; particular subset of acne pts)
2. Milk, particularly teenage boys who drink a lot of milk
What are some important aspects of acne pt education?
- Discourage picking bc can lead to permanent scarring
- Post-inflammatory hyperpigmentation
- Explain how to use medicines (pee-sized amount)
- Potential side effects
- Consistent use for 6-8 weeks minimum
When should you refer pts with acne?
- Severe Acne (cysts, nodules, scars)
- No response or poor response to treatment after 12 weeks
- If systemic antibiotics needed >1 year
- Isotretinoin being considered: females will NEED OCP (oral contraceptives)
- Acne associated with a systemic disease
What is rosacea? Causes?
- Relapsing and remitting facial erythema in pts over 30 years old (4 types); usually women with fair skin
- Causes:
1. Inflammation
2. Demodex folliculorum
3. Vascular abnormalities: tend to be prone to flushing
4. Genetics
5. Triggers: sunlight, exercise, hot/cold, stress, foods, alcohol
What are the clinical manifestations of rosacea? Types?
- Redness, flushing, pimples
- Four types:
1. Erythematotelangiectatic
2. Papulopustular
3. Phymatous: permanent swelling in the nose
4. Ocular
What is the tx for rosacea?
- Topical: usually a combo if severe
1. Metronidazole (cream or gel)
2. Azelaic acid
3. Sodium sulfacetamide with sulfur - Systemic: if more moderate to severe disease
1. Oral tetracyclines - Other: IPL (intense pulse light therapy), laser, sx
What is this? Suspected triggers?
- Periorifical dermatitis: women 20-45 yrs and prepubertal children (aka, periorbital dermatitis)
- Suspected triggers:
1. Steroids, topical
2. OCP (oral contraceptives)
3. Menstruation, pregnancy
4. Fluorinated toothpaste
5. Stress
6. Candida, demodex mites
What are the clinical manifestations of periorifical dermatitis?
-
Rash or “pimples” around mouth
1. Nose, eyes, labia
2. Papules, pustules, vesicles - May be kind of eczematous
- Granulomatous variant: longstanding in youth (top image)
What is the treatment for periorifical dermatitis?
- Discontinue all topical steroids
- Mild: topical antibiotics
- Severe: oral antibiotics
- May need topical non-steroidal anti-inflam (like Tacrolimus)
What causes folliculitis? How do you tell which one it is?
- Very common in hair-bearing areas
- Can usually determine cause via where it is occurring and PMH
-
Most common causes are bacterial:
1. Staph aureus
2. Streptococcus
3. Pseudomonas - Other Causes:
1. Fungal: pityrosporum orbiculare (yeast, fungus hybrid)
2. Mites: demodex folliculorum
3. Mechanical (i.e., on buttocks)
4. Eosinophilic folliculitis: HIV, transplant pts
What is this? How would you treat it?
- Clinical manifestations of folliculitis -> follicular based papules/pustules on hair-bearing areas
- Caused often based on where it is occurring and past medical history (PMH)
- TREATMENT: AB soaps/washes
1. Topical ABs: ok to use these by themselves in this context
2. Topical antifungals
What is hydradenitis suppurativa?
-
Apocrine gland bearing areas: axillary, inguinal, inframammary folds
1. Prevalence is 1-4%; mostly WOMEN - Risk factors: obesity, cigarette smoking, and family history
What are the clinical manifestations of hidradenitis suppurativa? Txs?
- Clinical manifestations: recurrent, persistent painful abscesses
1. Sinus tracts: chronic drainage
2. Scars
3. Also get comedones, a key to confirming the dx - Treatment:
1. Mild: topical and/or oral antibiotics
2. Moderate to severe: intra-lesional steroids, TNF-α inhibitors, surgery
What are the HSV types?
- dsDNA
-
HSV-1: peri-oral, lips, oral cavity
1. Abs in 85% of adults; can get initial outbreak when little, and not recurrences after that - HSV-2: genital -> Abs in 20-25% of adults (can also infect the mouth)
What are the 3 infection states of HSV? What will pt hx look like for each?
-
Primary: direct contact (vesicles) -> 3-7 days after exposure
1. Pain, burning, tingling, fever, malaise, LAD -
Latent: via sensory nerves to ganglion
1. Tends to be milder -
Recurrent: viral shedding
1. Fever, sun exposure, stress
What are the clinical manifestations of HSV?
- Clusters of monomorphous (all look the same) vesicles with an erythematous base
- “Punched out” erosions and crusted papules
- Usually start out with clear contents that become cloudy over time
What do you see here?
- HSV
- Clusters of monomorphous (all look the same) vesicles with an erythematous base
- “Punched out” erosions and crusted papules
- Usually start out with clear contents that become cloudy over time
How do you confirm HSV diagnosis?
-
Tzanck smear: look for multinucleated giant cells
1. Viral culture (48 hrs), PCR (faster, more $), direct fluorescent Ab -> really just depends on the institution - Most of the time this is a clinical diagnosis
- Can look like other conditions in children, however (like atopic dermatitis)
What is this?
- Tzanck smear for HSV: note the multinucleated giant cells
What should be in your differential for HSV?
- Impetigo: bacterial infection of skin with strep or staph (top image)
- Aphthous stomatitis (canker sore): tend to be larger and fewer in number (abscesses) -> middle image
- Syphilitic chancre: bottom image
What is the treatment for HSV?
- Mild: topical antiviral -> not as effective as oral
- Moderate to severe: systemic antiviral
- Oral or IV for pts who may be immunosuppressed
What is shingles? What are the triggers?
-
Reactivation of latent VZV (in dorsal root ganglia; dsDNA)
1. 20-30% lifetime risk (if you had chicken pox as a child) - Incidence/severity INC: after age 60, and in ppl who are immunosuppressed
- Triggers: trauma, stress, fever, radiation, immuno-suppression
What are the clinical manifestations of shingles?
- Prodrome: pain, pruritus, burning
-
Grouped vesicles over a dermatome: can get some additional lesions outside the dermatome too-
1. Trunk most common - Trigeminal nerve (V1, ophthalmic): 10 to 15%
1. Vesicles at tip/side of nose (Hutchinson’s sign) -> nasociliary branch
1. Eye: blindness -
V2 and/or V3: facial palsy
1. Ear: tinnitus, vertigo, deafness - Rash resolves within 3-5 weeks
-
Postherpetic neuralgia (esp. common on the face, and in older patients) -> 5-20%
1. Typically over 40 yrs old - Can get permanent scarring
What is this?
- Shingles: VZV
- Patients may think this is a bite at first
How can you confirm a VZV diagnosis?
- Tzanck smear
- Viral culture
- PCR
- Same as with HSV (which should also be in your differential -> would not be as painful, or along the dermatome)
Treatment and prevention of shingles?
- Oral antiviral w/in 72 hrs and pain med, esp. with facial type
- Vaccine (Zostavax) for people 60 yrs and older
1. Decreases risk of shingles by 51% and neuralgia by 67%
What is molluscum contagiosum?
- Cutaneous infection caused by Pox virus (dsDNA)
- Transmission: skin to skin, autoinoculation, fomites
1. Risk factors: atopic dermatitis, immuno-suppression, bathing/sleeping together
2. Children should not be kept out of school; casual contact should not spread disease -
Resolve spontaneously in months to years, but may leave depressed scar (that improves over time)
1. Discoloration common
What are the clinical manifestations of molluscum contagiosum?
- Small or lg pink to skin-colored 2-10 mm dome-shaped waxy papules
1. +/- central umbilication (can’t rely on this for diagnosis) - May cause “molluscum dermatitis:” pruritis
- Face, upper chest, extremities, other (common in creases: armpits, behind the knees, but really can be anywhere)
- Parents worry about eyelids -> conjunctivitis and keratitis are possible, but not common
What is this?
Molluscum contagiosum
What do you see here?
- Inflamed molluscum
- True infection is rare -> usually signals immune response and imminent resolution
What should be on your differential for molluscum?
- Acne (left): comedones, no umbilication
- Folliculitis (right): papules or pustules, no umbilication
What are the tx options for molluscum?
- Numerous methods, but NO CLEAR EVIDENCE to support any of them
- Active Nonintervention: self-limited
-
Physical Destruction
1. Curettage: more likely to leave scarring
2. Cryotherapy
3. Cantharidin: liquid that contains a vesicant (causes blister that dries up and falls off) - Local Irritation: topical retinoids, keratolytics
-
Immunomodulators:
1. Topical: Imiquimod -> very expensive and irritating
2. Systemic: intralesional antigens, cimetidine
What is Cantharidin?
- Chemical vesicant extracted from the blister beetle that is used to treat molluscum and warts
- Research: 90% cleared after avg of 2 applications; side effects -> erythema, blistering, pain
- High rate of parental and physician satisfaction
- Superficial blisters, so NO SCARRING -> some discoloration possible, but it will go away
What are warts? Causes?
- Common viral infection: HPV -> certain types have predilection to infect certain locations
- dsDNA
- >100 types
- Anywhere: hands, feet most common
- Benign, involute -> painful, embarrassing
- Some oncogenic: 16, 18, 31, 33