Derm General Flashcards
What is the bacteria involved in acne?
Propionibacterium acnes
What are open comodones?
blackheads
What are closed comodones?
whiteheads
What is the most mild form of acne?
comodonal
What is the worst type of acne?
nosulocystic
What are the 3 phases of the hair growth cycle?
anagen-growth
catagen-transitional
telogen-resting
How many hairs are normally lost in a day?
100
What is alopecia totalis?
complete loss of scalp hair
What is alopecia universalis?
loss of scalp and body hair
What does pityriasis mean?
small scaley patch
MRSA RF
Penetrating Trauma IVDA Abscess/Purulent Drainage History of MRSA Proximity to Others with MRSA Antibiotic Use Hospitalization
Describe the epidermis
outermost layer; water barrier, mechanical and UV protection, and immune surveillance
Describe the dermis
middle layer; provides mechanical protection and immune function.
- Papillary dermis
- Reticular dermis
- Adnexal structures
Describe the subcutis (hypodermis)
bottom layer; mechanical protection
What is the MC site of tumors?
skin
Define macule
flat, smaller than 2 cm (e.g., freckle)
Define patch
similar to macule but larger (e.g.,
childhood rash caused by measles)
Define papule
slightly elevated, smaller than 1 cm
e.g., eczema caused by allergy
Define nodule
similar to papule but greater than 1
cm (e.g., nevus)
Define tumor
nodule greater than 5 cm (e.g.,
melanoma)
Define vesicle
fluid-filled elevation of epidermis, smaller than 1 cm (e.g., herpesvirus lesion on the lip)
Define bulla
vesicle measuring more than 1 cm (e.g., burns)
Define pustule
vesicle filled with pus (e.g., impetigo)
Define ulcer
defect of epidermis (e.g., syphilitic chancre)
Define crust
skin defect covered with coagulated plasma (“scab”; e.g., healing wound)
Define scales
keratin layers covering skin as flakes or sheets; can be scraped away (e.g., seborrheic keratosis, psoriasis)
Define squames
large scales (e.g., as in ichthyosis)
Define excoriation
superficial skin defect caused by
scratching
Define fissure
sharp-edged defect extending
deeper into dermis (e.g., athlete’s foot)
Define Hyperkeratosis
Thickening of stratum corneum by abnormal keratin
Define Parakeratosis
Retention of nuclei in stratum corneum. Normal in mucous membranes
Define Hypergranulosis
Hyperplasia of stratum granulosum, usually caused by intense rubbing
Define acanthosis
Diffuse epidermal hyperplasia
Define papillomatosis
Hyperplasia and enlargement of contiguous dermal papillae
leading to surface elevation
Define dyskeratosis
abnormal keratinization occurring prematurely in cells below stratum granulosum
Define acantholysis
Loss of intercellular connections causing loss of cohesion between keratinocytes
Define spongiosis
Epidermal intercellular edema
Define orthokeratosis
thickened keratin without nucleus
Define first degree burn
Erythema, swelling; transitory, reversible
Define second degree burn
Blisters involving epidermis; hair follicles, adnexa
in dermis spared
Define third degree burn
Full-thickness burns; massive necrosis of
epidermis and parts of dermis, subcutis; cannot heal spontaneously
Define acne vulgaris
Infiltration and destruction of follicular epithelium by neutrophilic exudate
Define freckle
flat macule; responds to sunlight
Define lentigo
macule or papule; pigmented but
does not respond to sun
Define nevus
congenital or acquired
pigmentation in form of macule or papule or
even nodule
What is Breslow’s method?
measure from the granular layer of the epidermis to the deepest part oft he tumor
what is the most important prognostic factor of survival in MM?
tumor thickness
1mm low risk
>1mm higher risk
Define onychogryphosis
hypertrophic nail , related to trauma
Define koilonychia
thin and spoon nail, seen in iron deficiency anemia
Define onochomycosis
thicken, discolor, disfigure, and split nail, related to fungal infection.
Define paronychia
soft tissue infection, pus formation around a fingernail
How many eggs does an adult female head louse lay per day?
7-10/day
can lay 300 in a lifetime
Describe immediate drug induced skin reaction
occur less than 1 hour of the last administered dose.
Type I hypersensitivities: Urticaria (within 1 hr), angioedema (leaky blood vessels), anaphylaxis
Describe delayed drug induced skin reaction
IgE mast cell mediated occurring after one hour, but usually more than 6 hrs and occasionally weeks to months after the start of administration
What are examples of delayed drug induced skin reactions
Exanthematous eruptions
Fixed drug eruption
Systemic reactions (DIHS, SJS, TEN)
What drugs cause mast cell activation?
vancomycin
narcotics
What is the exception to the limited value of allergy testing for cutaneous reactions?
penicillin-want to skin test to evaluate type I, IgE mediated penicillin allergy
What is the most important data in determining if a rash is medication-related?
timing
Fitzpatrick I
White; very fair; red or blonde hair; blue eyes; freckles
Always burns, never tans
Fitzpatrick II
White; fair; red or blonde hair; blue, hazel, or green eyes
Usually burns, tans with difficulty
Fitzpatrick III
Cream white; fair with any eye or hair color; very common
Sometimes mild burn, gradually tans
Fitzpatrick IV
Brown; typically Mediterranean skin
Rarely burns, tans with ease
Fitzpatrick V
Dark brown; Middle-Eastern skin types
Very rarely burns, tans very easily
Fitzpatrick VI
Black
Never burns, tans very easily
How does narrow band UVB work?
focused wavelengths of 311-312 destroy immune cells that are attacking melanocytes
stimulates cytokine/GF release
How does PUVA work?
plant based chemical makes susceptible to UV radiation and uses UVA (less effective than UVB)
Etiology of folliculitis
Staph aureus
Gram ⊖
Pseudomonas aeruginosa (hot tub folliculitis)
Klebsiella, enterobacrer, Proteus
Etiology of paryonchia
S. aureus
Etiology of Impetigo
Staphlococcus aureus
Group A β-hemolytic Strep
Etiology of erysipleas
GAS
Staph aureus, Haemophilus
Cellulitis general etiology
Adults & Children-GAS, Staph aureus, MRSA
Facial & periorbital
H. influenzae
cellulitis etiology 2° dog & cat bites
Pasturella multocida
cellulitis etiology IVDA
S. aureus
Crepiant cellulitis etiology
Clostridia
Penetrating trauma, immunicomp cellulitis etiology
Pseudomonas aeruginosa
Phthirus pubis
crab lice
Pediculus humanus capitis
Head Lice
Pediculus humanus corporiss
body lice
Sarcoptes scabiei
Scabies
Cimex lectulrius
Bed bugs
Lo xosceles reclusa
Brown Recluse Spider
MC etiology of Tinea corporis?
T. rubrum
What should you tell a pateint with rosacea to avoid?
Spicy food, alcohol, extreme temperatures, caffeine
Etiology of Tinea versicolor
Malassezia yeast
What is the MC cutaneous drug eruption?
Exanthematous
What is ⊕Nikolsky’s sign
epidermis sheds off with lateral pressure
What drugs can cause SJS/TENS?
Sulfa abx (Bactrim) Allopurinol Tetracyclines Anticonvulsants (carbamazepine, lamotrigine, phenobarbital, phenytoin) NSAIDS Nevirapine Thiacetazone
What drugs can cause fixed drug eruption?
Phenolpphthalen Tetracyclines Metronidazole Sulfonamides Barbiturates NSAIDs Salicyates Yellow food coloring
Etiology of necrotizing fascitis
Clostridium
Etiology of Fournier Gangrene
E.coli
Bacteroides
Etiology of purpura fulminans
Neisseria menigitis
If there are >6 cafè au lait spots what do you need to do?
special considerations → check for tuberous sclerosis, neurofibramatosis, albright syndrome, fanconi anemia **
