Dermatology #1 Flashcards
What are the four main pathophysiology factors of acne vulgaris?
1) follicular hyperkeratinization
2) increased sebum production
3) Propionibacterium acne overgrowth (bacteria)
4) inflammatory response
What stimulates sebum production with acne vulgaris?
Androgens
Clinical manifestations of acne vulgaris
- Often occur in areas with sebaceous glands (chest, back, face, upper arms)
- Open comedones: blackheads (incomplete blockage)
- Closed comedones: whiteheads (complete blockage)
- Inflammatory: papules or pustules surrounded by inflammation
- Nodular or cystic: often heals with scarring
Explain the different severity levels of acne vulgaris (mild, moderate, and severe)
Mild: comedones, small amounts of papules/pustules
Moderate: comedones, larger amount of papules/pustules
Severe: nodular or cystic acne
Management of the three severities of acne vulgaris
- Mild: Topical (Azelaic acid, salicylic acid, benzoyl peroxide, retinoids. Tretinoin or topical ABX such as Clindamycin or Erythromycin)
- Moderate: As above + Oral ABX (Minocycline or Doxycycline). Spironolactone
- Severe: Oral Isotretinoin
What is the most effective medication for acne vulgaris and why?
Isotretinoin
-Affects all 4 pathophysiologic mechanisms of acne
Name 5 side effects of isotretinoin
- Dry skin and lips
- Highly teratogenic: must obtain at least 2 pregnancy tests prior to starting treatment and commit to 2 forms of contraception. Must sign up for iPledge. Monthly pregnancy tests before refills.
- Increased triglycerides and cholesterol
- Photosensitivity
- Worsening of Diabetes Mellitus
- Headache
- Fatigue
- Visual Changes
- Premature closure of long bones
Risk factors for acne rosacea
- Women
- 30-50 years old
What is acne rosacea?
Disease of pilosebaceous units associated with increased activity of capillaries, leading to telangiectasias and flushing secondary to vasodilation
Triggers of acne rosacea
Alcohol Hot or cold weather Hot drinks Hot baths Spicy foods Sun exposure Medications
(HEAT RELATED)
Symptoms of acne rosacea
- Acne-like rash (papulopustules)
- Centrofacial erythema
- Facial flushing
- Telangiectasias
- Skin coarsening with burning and stinging
- Red eyes
- Later, lymphedema, hyperplasia, and telangiectasias develop
- Rhinophyma (red, enlarged nose), otophyma (ear), gnathophyma (chin), metophyma (forehead), and blearophyma (eyelid)
Although a ______ is the definitive diagnostic for acne rosacea, it is rarely done.
Biopsy
Treatment for acne rosacea
- Lifestyle modifications: limit triggers, avoid irritants
- Topical metronidazole (first-line), Sodium sulfacetamide, erythromycin
- Oral ABX (Tetracycline, Minocycline, or Doxycycline if fail topical treatments)
- Oral isotretinoin if failed other treatments or severe
For the facial erythema of acne rosacea, what is a specific treatment/medication that can be given?
Topical Brimonidine
Risk factors for folliculitis
- Men
- Prolonged use of ABX
- Topical corticosteroids
MCC of folliculitis
Staph Aureus
MCC of hot tub-related folliculitis
Pseudomonas aeruginosa
Noninfectious folliculitis is common in what types of jobs?
People working hot, oil environments such as engine workers, on ships, machinists, or working in a hot, dirty environment
-Occlusion, perspiration, skin rubbing against tight clothing
Symptoms of folliculitis
- Singular or clusters of erythematous papules or pustules on hair bearing skin
- Not painful, but pruritic
- Abscesses may form at the site of severe folliculitis
Treatment for folliculitis
- Gentle cleansing with antibacterial soap and mild compresses
- Topical Mupirocin, Clindamycin, Erythromycin, or Benzoyl peroxide
- Oral ABX for severe: Cephalexin or Dicloxacillin
Treatment for hot tub folliculitis
usually resolves without treatment (severe cases may be treated with an oral fluoroquinolone such as Ciprofloxacin, Moxifloxacin)
What is Erythema Multiforme?
-Type IV hypersensitivity reaction of the skin following infections of medication exposure
MC infection that causes Erythema Multiforme
- Herpes Simplex Virus
- Mycoplasma sp is another common cause in children
Medications that cause Erythema Multiforme
-Sulfa drugs, beta-lactams, Phenytoin, Phenobarbital, Allupurinol
Explain the lesions in Erythema Multiforme
Target lesions that have 1) a dusky central area or blister, 2) surrounded by a pale ring of edema and 3) an erythematous halo on the extreme periphery
-Most common on extremities and trunk
Other symptoms of Erythema Multiforme
- Negative Nikolsky sign: no epidermal detachment. Often febrile.
- Minor: target lesions with no mucosal involvement
- Major: target lesions head –> centrally + mucosal membrane involvement (oral, genital, ocular). No epidermal detachment still.
What are the two types of Erythema Multiforme and how do they differ?
- Minor: no mucosal involvement
- Major: mucosal involvement
Treatment for Erythema Multiforme
- Symptomatic: discontinue offending agent, antihistamines, skin care. Diphenhydramine + Lidocaine mouth wash for oral lesions
- Systemic corticosteroids if severe. Oral Acyclovir if HSV related.
What are Steven-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN)?
Severe mucocutaneous reactions characterized by detachment of the epidermis and extensive necrosis
What is the difference between SJS and TEN?
SJS: sloughing involving < 10% of body surface involvement
TEN: sloughing involving > 30% of body surface involvement
Risk Factors/Causes of SJS/TEN
- Medications (MCC): Sulfa drugs, Anticonvulsants, Lamotrigine, Allopurinol, NSAIDS, antipsychotics, antibiotics
- Sulfa drugs: Bactrim, Glyburides
Symptoms of SJS and TEN
- Prodrome of fever, URI followed by widespread flaccid bullae beginning at trunk/face
- Pruritic target lesions (erythematous macule with purpuric centers) and involvement of at least 1 mucous membrane
- Positive Nikolsky sign (epidermal detachment)
- Ocular involvement common (uveitis, corneal ulceration)
Treatment for SJS/TEN
- Prompt discontinuation of causative agent
- Supportive therapy: treat like severe burns (burn unit admission, pain control, prompt withdrawal of offending medications, fluid and electrolyte replacement, wound care)
Alopecia Areata is commonly associated with
Other autoimmune disorders: thyroid disease, Addison’s disease, etc.
Exam findings of Alopecia Areata
- Exclamation point hairs: short hairs broken off a few mm from the scalp. Tapering near the proximal hair shaft.
- Nail abnormalities: pitting, trachyonychia (roughening of the nail plate)
- Smooth, discrete, circular patches of complete hair loss that develop over a few weeks
What gives a definitive diagnosis of alopecia areata?
-Punch biopsy
Treatment for alopecia areata
- Local: intralesional corticosteroids
- Extenstive: topical corticosteroids
What is alopecia totalis and alopecia universalis?
Totalis: complete scalp hair loss
Universalis: complete hair loss on scalp and body, including eyelashes
What is androgenetic alopecia?
Genetically predetermined loss of terminal hairs on scalp in a pattern. Most common type of hair loss in men and women.
What is the key androgen that leads to hair loss in androgenetic alopecia
Dihydrotestosterone (DHT)
Activation of DHT does what in androgenetic alopecia?
Shortens the anagen (growth phase) in the normal hair growth cycle
-Pathologic specimen show decreased anagen to telogen ratio
Symptoms of androgenetic alopecia
- Hair thinning and non scarring hair loss
- -In males, it begins as bitemporal thinning of frontal scalp then involves vertex
- -In females, thinning of hair between frontal and vertex of scalp without affecting frontal hairline
Treatment for androgenetic alopecia
- Topical Minoxidil: Requires 4-6 month trial and must be used indefinitely
- Oral Finasteride
- Hair transplant
Mechanism of action of Minoxidil
-Widens blood vessels, allowing more blood, oxygen, and nutrients to promote the anagen (growth phase)
Finasteride, a 5-alpha reductase type 2 inhibitor, has a MOA of
-androgen inhibitor (inhibits the conversion of testosterone to dihydrotestosterone)
What are some adverse effects of Finasteride?
Decreased libido, sexual or ejaculatory dysfunction, increased risk of prostate cancer
-Category X
Explain the Rule of 9’s (Anterior/Posterior)
Anterior
- Head: 4.5%
- Torso: 9%
- Belly: 9%
- Genital: 1%
- Arm: 4.5%
- Leg: 9%
Posterior:
- Head: 4.5%
- Torso: 9%
- Lower Back: 9%
- Arm: 4.5%
- Leg: 9%
What is considered a “minor burn” in adults and children/old?
Adults: < 10% TBSA
Children/Old: < 5% TBSA
–Must be isolated injury
–Must NOT involve face, hands, perineum, feet
-Must NOT cross major joints or circumferential.
What is considered a MAJOR burn in adults and children/old?
Adults: > 25% TBSA
Children/Old: > 20% TBSA
-Burns involving: face, perineum, hands, feet
-Burns crossing major joints, circumferential
What is the rule of 9’s chart that is used (the specific name of it)?
Lund-Browder Chart (most specific)
