Dermatology Flashcards
1
Q
Age: 30-40s
bulllae - thin and fragile, painful NOT ITCHY
involves mouth
Nikolsky’s sign
A
Pemphigus Vulgaris
“so bad it’s vulgar”
2
Q
Abs in Pemphigus Vulgaris
A
Abs against desmosomes (against Ags in the intercellular spaces of the epidermal cells)
3
Q
In what conditions can you see Nikolsky’s sign
A
Pemphigus Vulgaris
Staphylococcal Scalded Skin Syndrome
Toxic Epidermal Necrolysis
4
Q
Dx and Tx of Pemphigus Vulgaris
A
DX: bx of skin
TX: PO glucocorticosteroids
5
Q
Age: 70-80s
bulllae - tense, thick (don’t rupture), painful, ITCHY
DOESN’T INVOLVE MOUTH
NO NIKOLSKY’S SIGN
A
Bullous Pemphigoid
6
Q
Abs in Bullous Pemphigoid
A
Abs against hemidesmosomes (IgG and C3 deposits at dermal-epidermal junction)
7
Q
Dx and Tx of Bullous Pemphigoid
A
DX: bx from edge of blister
TX: PO glucocorticosteroids
8
Q
Non-healing PAINLESS blisters (increased fragility) on sun-exposed areas of the body (backs of hands and face)
Hyperpigmentation of skin
Hypertrichosis of face
A
Prophyria Cutanea Tarda
Def. in enzyme uroporphyrinogen decarboxylase = accumulation of porphyrins (in heme pathway)
9
Q
What conditions are associated w/ Prophyria Cutanea Tarda
A
Hep C
OCPs
Alcoholism
Liver Disease
10
Q
Dx and Tx of Prophyria Cutanea Tarda
A
DX: test for urinary uroporphyrins
TX:
- stop alcohol, estrogen use
- use sun protection
- use phlebotomy
- chloroquine to increase excretion of porphyrins
11
Q
HSN Rxn Type I –> mediated by IgE and mast cell activation
wheals and hives
itching
A
Urticaria
12
Q
Common causes of Urticaria
A
MDXs insect bites foods emotions contact w/ latex
Causes of Chronic urticaria:
- cold
- vibration
- pressure on skin (dermatographism)
13
Q
Tx of Urticaria
A
Acute Therapy: H1 antihistamines (eg. diphenhydramine) PO steroids (if life threatening)
Chronic Therapy:
Non-sedating antihistamines (eg. loratadine)
Desensitization (if trigger can’t be avoided)
14
Q
Milder version of urticaria
Generally due to MDXs the pt is allergic to
Maculopapular eruption that blanches w/ pressure
A
Morbiliform Rash
TX: antihistamines
15
Q
Targetlike lesions that can be confluent
On palms and soles
NO mucous membrane involvement
Nonspecific prodrome: fever, malaise, sore throat
A
Erythema Multiforme
TX: antihistamines
16
Q
Causes of Erythema Multiforme
A
Infxn w/ herpes simplex (MCC) or mycoplasma
Malignancy and collagen vascular disease
MDXs:
- PNC
- NSAIDs
- Sulfa drugs
- Phenytoin
- Allopurinol
17
Q
Acute flu-like prodrome Rapid onset red macules, vesicles, bullae Mucous membrane involvement < 10-15% total body surface area Necrosis and sloughing of epidermis
A
Stevens-Johnson Syndrome
TX:
- admit to burn unit
- IVIG
18
Q
Causes of Stevens-Johnson Syndrome
A
MDXs:
- PNC
- NSAIDs
- Sulfa drugs
- Phenytoin
- Allopurinol
- Phenobarbital
19
Q
30-100% total body surface area
40-50% mortality rate
Nikolsky’s sign (skin sloughs off easily)
A
Toxic Epidermal Necrolysis
DX: skin bx
Causes: MDX (vs. Staphylococcal scalded skin syndrome caused by toxin from bacteria)
20
Q
painful, red, raised nodules on anterior surface of shins
A
Erythema Nodosum
21
Q
Causes of Erythema Nodosum
A
secondary to recent infxns (eg. strep) or inflammatory conditions including:
- pregnancy
- coccidioidomycosis
- histoplasmosis
- sarcoidosis (get CXR)
- UC
- syphilis
- hepatitis
22
Q
Tx of Erythema Nodosum
A
Analgesics + NSAIDs
Tx underlying dx
23
Q
scattered papules w/ some red, SCALY areas on scalp
PATCHY HAIR LOSS
lymphadenopathy and SCARRING
A
Tinea Capitis
DX: KOH prep of hair shaft
24
Q
Tx of Tinea Capitis
A
PO antifungal
- -> griseofulvin
- -> terbinafine
- -> itraconazole
Prevent by not sharing hats/combs
25
Tx for nail fugal infxn
PO antifungal x 6 wks (fingernails) OR x 12 wks (toe nails)
- -> griseofulvin
- -> terbinafine
- -> itraconazole
26
on arms/legs
| red, itchy, scaly, RING-SHAPED lesions w/ raised borders that CLEAR CENTRALLY while expanding peripherally
Tinea Corporis
27
Tx for Tinea Corporis
PO griseofulvin
28
fungal infxn of hands
seen in pts w/ pre-existing tinea pedis
red, itchy, scaly, cracking lesions
Tinea Manuum
29
Tx of Tinea Manuum
Topical antifungal (eg. miconazole)
30
HYPOPIGMENTED or light brown or pink macules often found on back, shoulders, or neck
Macules DON'T TAN (more apparent in summer/spring)
Tinea Versicolor (due to Malassezia furfur)
31
Dx and Tx of Tinea Versicolor
DX: see hyphae and spores (spaghetti and meatballs)
TX:
First line: ketoconazole 2% shampoo (selenium sulfide shampoo)
PO antifungal (if resistant to tx)
32
Tx Guidelines for Nail or Scalp Fungal Infxn
use PO antifungals:
- -> griseofulvin
- -> terbinafine (SE: hepatotoxic)
- -> itraconazole
33
Tx Guidelines for Fungal Infxn NOT involving hair or nail
use topical antifungals:
- -> terbinafine (SE: hepatotoxic)
- -> clotrimazole
- -> ketoconazole (SEs: hepatotoxic, gynecomastia)
- -> miconazole
- -> nystatin
34
Tx Guidelines for Bacterial Skin Infections (eg. impetigo, cellulitis, folliculitis)
use PO dicloxacillin or cephalexin
use IV oxacillin or nafcillin OR IV cefazolin
if suspecting MRSA use IV vanc (PO equivalent = clindamycin, linezolid, Bactrim, doxycycline)
35
weeping, crusting, oozing of skin
| small, yellow ("honey colored") pustules on face especially child
Non-Bullous Impetigo
36
Cause and Predisposing Factors to Non-Bullous Impetigo
CAUSE:
S. aureus or S. pyogenes (Grp A Strep)
Predisposing Factors:
pre-existing skin trauma (eg. insect bite)
atopic dermatitis (eczema)
37
Tx of Non-Bullous Impetigo
TOPICAL mupirocin
| Severe disease = PO dicloxacillin or cephalexin
38
Cause and Sxs of Bullous Impetigo
CAUSE:
S. aureus ONLY
SXs:
Rapidly growing flaccid bullae w/ yellow fld
39
Tx of Bullous Impetigo
PO dicloxacillin or cephalexin
40
abrupt onset
skin (eg. face) is bright red, hot and raised w/ sharp borders
area is painful and hyperesthetic to touch
fever, chills, malaise (systemic sxs)
Erysipelas
41
Tx of Erysipelas
```
First Line: PO dicloxacillin or cephalexin
Severe disease (w/ systemic sxs): IV oxacillin or nafcillin OR IV cefazolin
```
42
Complications of all skin infxns
Glomerulonephritis (NOT R. fever)
43
warm, red, swollen, tender skin
Cellulitis
44
RFs for Cellulitis
obesity
| disruption of skin (eg. by tinea pedis --> tx foot fungus in pts w/ recurrent cellulitis)
45
Difference b/w Cellulitis or DVT
Cellulitis has ↑ WBCs and NO risks of hypecoagulability
46
Cause of Cellulitis
S. aureus and S. pyogenes
47
Tx of Cellulitis
```
First Line: PO dicloxacillin or cephalexin
Severe disease (w/ systemic sxs): IV oxacillin or nafcillin OR IV cefazolin
```
48
Tx of Folliculitis
Topical mupirocin
49
Tx of Furuncles and Carbuncles
PO dicloxacillin or cephalexin
50
severe, life threatening infxn
cellulitis that dissects into the fascial planes of skin
very high fever
have hx of laceration, trauma, surgical procedure (portal of entry into skin)
pain out of proportion to superficial appearance
bullae
palpable crepitus (in C. perfringes infxn)
Necrotizing Fasciitis
51
MC organisms involved in Necrotizing Fasciitis
Streptococcus (Grp A Strep) and Clostridia
52
Dx of Necrotizing Fasciitis
↑ CPK
X-ray/CT/MRI --> shows air in tissue (black circles) or necrosis
Surgical debridement = BEST Dx and Tx
53
Tx of Necrotizing Fasciitis
Surgical debridement
Broad spectrum ABX until cx results come back
--> piperacillin/tazobactam + Vancomycin + Clindamycin
Mortality rate = 80%
54
Tx for Acute Herpes
PO acyclovir
| Acyclovir - Resistant herpes = PO Foscarnet
55
Herpetic Whitlow
non-purulent vesicles on hands
Tx: self-limited
56
Ramsay Hunt Syndrome (herpes zoster oticus)
HERPES ZOSTER = SHINGLES = REACTIVATION OF VZV (VARICELLA = HHV 3)
ear manifestation of reactivated zoster virus:
- -> ear pain
- -> vesicles in external auditory canal
- -> I/L facial paralysis
57
Tx of Ramsay Hunt Syndrome (herpes zoster oticus)
IV acyclovir
58
Who gets Zoster (VZV) vaccine?
≥ 60 yoa (not for HIV pts w/ CD4 <200, pregnant pts, pts w/ immunodeficiency or on immunosuppressive therapy)
59
Who gets treated for Herpes Zoster/Varicella
Immunocompromised child OR primary infxn in adult
60
Tx for Herpes Zoster/Varicella if:
| pt comes w/in 72 hrs of rash vs. pt comes > 72 hrs after rash
Within 72 hrs of rash --> PO acyclovir or PO valacyclovir (better than acyclovir) to PREVENT postherpetic neuralgia (NOT to prevent rash from spreading)
>72 hrs after rash --> give pain MDX and zinc oxide cream
61
Acute Herpetic Neuralgia
persists ≤ 30 days from rash onset
Tx: NSAIDs, analgesics
62
Subacute Herpetic Neuralgia
persists > 30 days but resolves within 4 months of rash onset
Tx: NSAIDs, analgesics
63
Postherpetic Neuralgia
persists > 4mo from rash onset
Tx: Gabapentin, TCAs, pregabalin
64
Tx of Primary (chancre) and Secondary Syphilis
IM PCN (single dose)
65
cutaneous warts
--> hyperkeratotic papules on soles of foot
--> thickened, enlarging papule
infxn via skin to skin contact
Plantar Warts (from HPV)
Dx: scrapings of hyperkeratotic debris confirm dx
66
Tx of Plantar Warts
initial = salicyclic acid (takes 2-3 wks to notice change)
67
How is Scabies transmitted and Tx?
Person to person contact
Tx: 5% permethrin cream
- -> must tx all household contacts and bedding/clothes need to be washed
- -> if can't use topical therapy (eg. in nursing home), then use PO ivermectin
68
Tx for Lice?
5% permethrin cream
69
Tx of Lyme rash
PO doxycycline or amoxocillin
70
Fever > 102F
SBP <90
desquamative rash (diffuse, red macular rash --> like sunburn)
vomiting
involvement of mucous membranes of eye, mouth, genitals
↑ Cr, CPK, LFTs, Bands
↓ PLT
Toxic Shock Syndrome
--> caused by staph via exotoxin (TSS toxin 1)
71
Tx for Toxic Shock Syndrome
```
vigorous fld resuscitation
antistaph MDXs (eg. nafcilin)
```
72
superficial flaccid bullae, perioral crusting then subsequent scaling and desquamation
Nikolsky's sign
NORMAL BP (unlike TSS)
NOT full thickness split (like TEN)
Staphylococcal Scalded Skin Syndrome
--> mediated by toxin from Staph
73
Tx of Staphylococcal Scalded Skin Syndrome
```
Manage in burn unit
Antistaph ABXs (ABXs don't reverse disease but they kill Staph that is producing toxin)
```
74
papule appears then get central necrosis (black in color) surrounded by edematous ring --> "black eschar or black scab"
Anthrax
From Bacillus anthracis (in ppl with livestock contact)
TX: ciprofloxacin or doxycycline
75
Dx and Tx of Melanoma
DX: excisional bx
TX: excision w/ wide margins
76
Ocular Melanoma
primary malignant tumor arising from melanocytes w/in uvea
| blurry vision, progressive and painless visual field abn
77
Dx of Ocular Melanoma
U/S of eye
| MRI (for staging)
78
Tx of Ocular Melanoma
Asymptomatic pt w/ small lesions (diameter <10mm, thickness <3mm) --> observe w/o tx; repeat exam in 3 months and every 6 months thereafter
Symptomatic pt w/ large lesions (diameter ≥ 10mm, thickness ≥3mm) --> need radiotherapy
79
stuck on appearance of hyperpigmented lesions
Seborrheic Keratosis
--> assoc. w/ GI and lung tumors (explosive onset of multiple pruritic lesions --Lesar Trelat sign)
80
Precancerous lesions on sun-exposed areas in old ppl
| rough, small, red papules w/ yellow/brown scales ("sandpaper like texture")
Actinic Keratoses
- -> can regress and recur
- -> 20% risk of SCC
TX: sunscreen, 5-FU, cryotherapy
81
suspect in pt w/ chronic scar that develops into non-healing, painless, bleeding ULCER
on sun-exposed areas in old ppl
Squamous Cell CA
DX: Punch Bx
TX: Mohs surgery (if don't want surgery = radiation)
--> metastatic D = chemo
82
Presents like SCC but comes and goes
| flesh colored lesion w/ central crater that contains keratinous material
Keratocanthoma
Tx: goes away on it's own (if not, resect)
83
shiny, pearly appearance w/ telengectasias and rolled edges
Basal Cell CA
DX: Punch Bx
TX: Mohs surgery
84
```
benign vascular skin tumor
on lip/oral mucosa
red, small papule that grows rapidly over wks or months and forms pedunculated or sessile shiny mass
can occur after trauma
bleeds w/ minor trauma
common in pregnant pts
```
Pyogenic Granuloma
85
SCC in situ
Bowen's Disease
86
purple lesions on skin (including genitalia, LE, face) in pts w/ HIV and CD4 <100
Kaposi's Sarcoma
(HHV 8)
Tx: antiretroviral therapy
87
silvery scales on extensor surfaces that bleed when scraped off
nail pitting
Psoriasis (in adults)
88
Tx for Psoriasis
1) Emollients
2) Salicyclic acid to remove collections of scaly material so other therapies can work
3) Mild - Moderate Psoriasis --> localized, topical HIGH POTENCY steroids (0.05% fluocinonide)
4) Severe Plaque Psoriasis (>10% body involved) --> UV light, methotrexate
5) Extensive psoriatic arthritis and psoriasis involving nails --> methotrexate
89
Tx of Facial and Intertriginous Psoriasis
Topical tacrolimus
| Topical, LOW POTENCY steroids (1% hydrocortisone)
90
What is Guttate Psoriasis? Tx?
red, scaly, small teardrop shaped spots
Tx: observation
91
red, itchy plaques of flexor surfaces ("itch that rashes")
scaly rough areas of thickened skin
↑ IgE
Atopic Dermatitis (Eczema) --> onset before age 5
Allergic triad:
- asthma
- allergic rhinitis
- eczema
92
Complication of Eczema
superficial skin infxns due to scratching
93
Tx of Eczema
Prevent w/ emollients
Active Disease managed w/ topical steroids (eg. triamcinolone) OR antihistamines
Tacrolimus for areas where steroids CI (eg. face, eyelids, flexor surfaces)
94
umbilicated vesicles (superimposed on healing atopic dermatitis lesions)
fever
adenopathy
Eczema Herpeticum
--> form of primary HSV infxn (life threatening in infants)
TX: acyclovir
95
dermatitis that involves palms and soles
| assoc w/ redness, itching, scaling
Dyshidrotic Eczema
96
very itchy patches of eczema on back and LEs
Nummular Eczema
97
Dandruff on face
scaly, greasy, flaky skin on red base found on scalp, eyebrows, nasolabial folds, chest, upper back, axilla, inguinal/pubic area
Seborrheic Dermatitis
98
Tx of Seborrheic Dermatitis
```
LOW POTENCY steroids (hydrocortisone)
Topical antifungal (eg. selenium sulfide, ketoconazole)
```
Chronic relapsing condition (so need tx every 1-2 wks)
99
thickened, excoriated plaques caused by persistent scratching and rubbing
occurs in areas easy to reach (eg. arms, legs neck)
assoc w/ anxiety disorders
Lichen Simplex Chronicus
100
itchy eruption that begins w/ herald patch then disseminates
NO palms/ sole involvement
Pityriasis Rosea
TX: self limited
101
facial erythema w/ telengiectasias staring at nose and cheeks
recurrent facial flushing provoked by various stimuli including hot/spicy foods, alcohol, temp extremities, emotional rxns
inflammatory pustules
no comedones
ocular sxs (burning sensation, conjunctivitis, etc)
Rosacea
102
Tx of Rosacea
Topical metronidazole
PO doxycycline
Severe, refractory cases = isotretinoin
Rhinophyma = laser surgery
103
Tx of Comedonal Acne
topical retinoids +/- salicyclic glycolic acid
104
Tx of Inflammatory Acne
Mild: topical retinoids + benzoyl peroxide
Moderate: add topical ABXs
Severe: add PO ABXs
105
Tx of Nodular (Cystic) Acne
Moderate: topical retinoids + benzoyl peroxide + topical ABXs
Severe: add PO ABXs
106
SEs of Isotretoin
```
metabolic effects
--> hyperglycemia, hyperTG (look out for pancreatitis)
hepatotoxicity
teratogen
ocular toxicity
bld dyscrasias
mucocutaneous rxns
```
