2014-03-07 USMLE Derm - USMLE Derm Flashcards
(172 cards)
1
Q
Define macule and give an example
A
- flat spot less than 1 cm
- freckles
2
Q
Define patch adn give an example
A
- flat spot greater than 1cm
- port wine stain
3
Q
Define papule and give 3 examples
A
- solid elevated palpable lesion less than 1cm
- wart, acne, lichen planus
4
Q
Define plaque and give an example
A
- solid flat topped elevate palpable lesion greater than 1cm
- psoriatic patch
5
Q
Define nodule and give 2 examples
A
- palpable solid lesion greater than 1cm (not flat topped)
- small lipoma, erythema nodosum
6
Q
Define vesicle and give 2 examples
A
- elevated, circumscribed lesion less than 5mm containing fluid
- small blister
- chickenpox, HSV
7
Q
Define bulla and give 2 examples
A
- elevated, circumscribed, fluid filled lesion greater than 5mm
- large blister
- contact dermatitis, pemphigus
8
Q
Define wheal and give an example
A
- itchy transiently edematous area
- allergic reaction
9
Q
General definition of vitiligo
A
depigmentation of unknown etiology
10
Q
Vitiligo is often associated with
A
autoimmune conditions like pernicious anemai and hypothyroidism
11
Q
Patients with vitiligo may have antibodies to
A
melanin
12
Q
Biopsy in vitiligo may show
A
absense of melanocytes
13
Q
Puritis is often a clue to these diseases:
A
- obstructive biliary disease
- uremia
- polycythemia rubra vera
- atopic dermatitis
- scabies
- lichen planus
14
Q
Puritis after a warm shower may be a clue to
A
polycythemia rubra vera
15
Q
Pruritis with obstructive biliary disease is classically ________
A
primary biliatry cirrhosis
16
Q
The most common form of contact dermatitis in women
A
nickel dermatitis (jewlery)
17
Q
Contact dermatitis is usually this type of reaction
A
type IV hypersensitivity
18
Q
List three classic offending agents for contact dermatitis
A
nickel, deoderant, poison ivy
19
Q
Describe the rash of contact dermatitis
A
- well circumscribed
- only in areas of exposure
- red
- itchy
- often with vesicles or bullae
20
Q
Testing and treatment of contact dermatitis
A
- patch test
- avoid offending agent
21
Q
Major features of atopic dermatitis
A
- chronic
- begins in 1st year of life
- rash is red, itchy, weeping on head and arms sometime diaper area
22
Q
Main symptoms of atopic dermatitis
A
itching and skin breaks lead to possible infection risk
23
Q
Treatment of atopic dermatitis
A
- avoid dry soaps
- antihistamines
- topical steroids
24
Q
What is blepharitis?
A
seborrheic dermatitis of the eyelid
25
3 common subtypes of seborrheic dermatitis
- cradle cap
| - dandruff- blepharitis
26
Classic findings of seborrheic dermatitis
scaling skin on scalp and eyelids
27
Treatment of seborrheic dermatitis
dandrum shampoo (selenium sulfide)
28
fungal infection on the trunk is called
tinea corporis
29
describe the lesion of tinea corporis
- red
- ring-shaped
- raised borders
- clear centrally while they expand peripherally
30
fungal infection on the feet is called
tinea pedis
31
describe the lesion of tinea pedis
- macerated
- scaling web spaces
- itches
32
thicked distorted toenails are often
onychomycosis
33
Most important part of treatment for tinea pedis
good foot hygeine
34
fungal infection of the nails is called
tinea unguium or onychomycosis
35
fungal infection of the scalp is called
tinea capitis
36
is tinea capitis contagious?
yes, very
37
an inflammed boggy granuloma of the scalp is called
kerion
38
Describe the characteristics of tinea capitis
- sclay patches of hair loss
| - boggy granulomas (kerions)
39
technical name for jock itch and what type of infection
- tinea cruris (crural folds)
| - fungal infection
40
Most skin fungal infections are caused by
Trichophytan species
41
How do you confirm a tinea infection?
scraping of sking with KOH prep or by culture
42
Pharmacologic treatment of tinea infections
- tinea capitis: oral agent
- onychomycosis: oral agent
- others can be treated with topical and/or oral
43
Typical oral and topical treatments for tinea
- terbinafine, fluconazole
| - topical imidazoles (miconazole, clotrimazole, keotoconazole)
44
Differentiation of causative organism in tinea capitus
- if hair fluoresces under the wood's lamp = microsporum
| - otherwise = trichophyton
45
Physical appearance of thrush
white patches on tongue or buccal mucosa that can be scraped off
46
When is candial infection considered normal/non-concerning
- children
| - vulvovaginitis in women esp when pregnant or on antibiotics
47
Thrush without good explanation should prompt consideration of...
- immunodeficiency
| - diabetes
48
Treatment of trush
- topical with nystatin or imidazoles
| - systemic for resitant disease
49
Systemic therapies for thrush
- nystatin
| - ketoconazole
50
Multiple patches of various size and color on the torso in a young adult =
tinea versicolor
51
Characteristics of tinea versicolor
- young adults
- multiple patches of various size and color on the torso
- patches fail to tan (often noted in summer)
52
Diangosis of tinea versicolor
- clinical
| - KOH prep
53
Treatment of tinea versicolor
- selenium sulfide shampoo
| - topical imidazoles
54
Classic areas for scabies
- finger web spaces
| - flexor surfaces of the wrist
55
Treatment of scabies
- permethrin
- technically lidocaine can be used but has a risk of neurotoxicity especially in young children
- remember to treat all contacts
56
Pediculosis =
lice
57
The technical name for lice is
pediculosis
58
head lice is called
pediculus capitis
59
body lice is called
pediculus corporis
60
pubic lice is called
phthirus pubis
61
Treatment of lice
- permethrin
62
Genital warts that are associated with cancer
HPV 16 and 18 are associated with cervical cancer
63
Warts are most commonly seen ________
in older children, on the fingers
64
Are warts infectious?
yes
65
Warts are caused by
human papillomavirus
66
Typical treatments for warts
- salicylic acid
- liquid nitrogen
- curettage
67
Scabies is caused by
sarcoptes scabei
68
Halmark lesion of scabies
burrow on:
- finger web spaces
- flexor surfaces of the wrist
69
Treatment of scabies
Permethrin
| - be sure to treat contacts
70
Pediculosis =
lice
71
Lice is also called
pediculosis
72
Pediculus capitis is common in
school children
73
Pediculus corporis usually involves
poor hygeine
74
Phthirus pubis is
sexually transmitted lice
75
Diagnosis of lice is made by
seeing lice on hair shafts
76
Treatment of lice
- permethrin
| - decontaminate combs, hats, sheet, clothing
77
Warts are caused by
human papillomarvirus (HPV)
78
Warts in children are often seen
on the hands
79
Genital warts are caused by
HPV 16 and 18
80
Genital warts are associated with
cervical cancer
81
Treatment of warts
- salicylic acid
- liquid nitrogen
- curettage
82
molluscum contagiosum is a
poxvirus
83
Molluscum contagiosum is common in
- children
- STD
- don't forget autoinnoculation
84
Appearance of mollusceum contagiosum
- skin-colored
- smooth
- waxy papules
- central depression (umbilitated)
85
A 0.5cm waxy skin colored umbilicated papule =
molluscum contagiosum
86
Characteristic pathologic appearance of molluscum contagiousum
inclusion bodies
87
Treatment of molluscum contagiousum
- freezing
| - curettage
88
5 common "medical" descriptions of acne
- comedones (whiteheads/blackheads)
- papules
- pustules
- inflammed nodules
- superficial pus-filled cysts
89
Gland that gets blocked in acne
pilosebaceous glands
90
Organism often involved in acne
Propionibacterium acnes
91
Acne is NOT related to
- exercise
- sex
- masturbation
92
Progression of treatment options for acne
- topical benzoyl peroxide
- topical clindamycin
- oral tetracycline or erthromycin
- topical tretinoin
- oral isotretinoin
93
Antibiotic for eradication of propionibacterium acnes
erythromycin
94
Side effects of oral isotretinoin
- dry skin
- dry mucosae
- muscle and joint pain
- abnormal LFTs
95
This looks like acne but usually starts in middle age
Rosacea
96
Rhinophyma =
bulbous red nose
97
Bulbous red nose in rosacea =
rhinophyma
98
Rosacea often also has
rhinophyma and blepharitis
99
Pathogenesis of rosacea
unknown (but not related to diet)
100
Treatment of rosacea
- topical metronidazole
| - oral tetracycline
101
Signs of virilization
- hirsutism
- deepening voice
- clitoromegaly
- frontal balding
102
Most common cause of virilization
idiopathic
103
Hirsutism is often a sign of
virilization
104
More common causes of hirsutism
- androgen secreting ovarian tumor
- corticosteroids
- Cushing syndrome
- Stein-Leventhal syndrome
- minoxidil
- phenytoin
- other drugs
105
Stein-Leventhal syndrome =
polycystic ovarian disease
106
Psychiatric disorder where one pulls out hair
trichotillomania
107
trichotillomania =
pathological hair pulling
108
What is alopecia areata
- form of baldness
- idiopathic
- associated with antimicrosomal and other antibodies
- seen with lupus, syphilis, after chemo
109
Key features of male-pattern baldness
- benign
- requires androgen expression
- considered genetic
110
Classic lesions of psoriasis
- dry
- NOT pruritic
- well-circumscribed
- silvery
- scaling
- papules/plaques
- on extensor surfaces/scalp
111
A dry well-circumscribed, silvery, scaling papule on the scalp or extensor surfaces =
psoriasis
112
Family history for psoriasis
often positive
113
Psoriatic arthritis is RF
negative
114
People with psoriasis often have nails that are
pitted
115
Psoriasis is most often seen in
- whites
| - onset early adulthood
116
General treatment of psoriasis
- UV light
- lubricants
- topical corticosteroids
- keratolytics
117
Examples of keratolytics (such as in treatment of psoriasis)
- coal tar
- slicylic acid
- anthralin
118
Age for pityriasis rosea
adults
119
Scaly slightly erythematous ring-shaped lesion on the trunk =
"hearld patch" of pityriasis rosea
120
Lesions of pityriasis rosea
- scaly red itchy ring shaped
- starts with hearld patch on trunk
- 1 weeks later many more appear
- follow langerhan's skin cleavage lines
- often in "Christmas tree"
121
Rash with "Christmas tree" pattern
pityriasis rosea
122
General course of pityriasis rosea
spontaneously remits in 1 month
123
Ddx of pityriasis rosea
syphilis
124
Treatment of pityriasis rosea
reassurance
125
Features of lichen planus:
"The 4 P's":
- pruritic
- purple
- polygonal papules
126
pruritic purple polygonal papules =
lichen planus
127
Classic location of lichen planus
wrists and/or ankles
128
Typical course and treatment of lichen planus
- self-limited and resolves within a few years
| - symptomatic treatment for itching
129
2 major drug causes of photosensitivity
- tetracycline
| - phenothiazines
130
Classic lesions of erythema multiforme
- target of iris lesions
131
Infection that can cause erythema multiforme
- herpes
132
Erythema multiforme is usually caused by
- drugs
| - infections
133
Characteristic feature of Stevens-Johnson syndrome
Erythema multiforme with mucosal involvement
134
Treatment of erythema multiforme
supportive
135
Typical description of erythema nodosum
- inflammatory
- subcutaneous tissue and sin
- tender red nodule
136
Classic location of erythema nodosum
- shins (pre-tibial)
137
Classic causes of erythema nodosum
- unknown
- streptococcal
- sarcoidosis
- coccidiomycosis
- ulcerative colitis
138
pemphigus vulgaris is an _______ disease
autoimmune
139
Typical age for pemphigus vulgaris
middle and older age
140
Typical lesions of pemphigus vulgaris
- multiple bullae starting with oral mucosa
| - blisters slough and leave raw skin
141
Multiple bullae starting with oral mucosa, blisters then slough =
pemphigus vulgaris
142
Biopsy of pemphigus vulgaris shows
(stain for antibody)
| - lacelike/fishnet immunofluoresence
143
Treatment of pemphigus vulgaris
corticosteroids
144
Death from pemphigus vulgaris is often due to
- secondary skin infection
| - fluid loss
145
Compare biopsy results of pemphigus vulgaris vs bullous pemphigoid
- lacelike/fishnet = vulgaris
| - linear = pemphigoid
146
Dermatitis herpetiformis is a tip-off for
gluten sensitivity (celiac disease)
147
Pathology of dermatitis herpetiformis
IgA deposits (even in unaffected areas)
148
Pruritis vesicles, papules and wheals on extensor aspects of elbows and knees +/- face/neck =
dermatitis herpetiformis
149
Treatment of dermatitis herpetiformis
gluten-free diet
150
3 major causes of new onset excessive perspiration
- hyperthyroidism
- pheochromocytoma
- hypoglycemia
151
Reasons to bioby/excise a mole
- enlarges
- irregular borders
- darkens/inflammed
- changes color
- bleeds
- itches
- painful
152
Characteristics of dysplastic nevus syndrome
- genetic
- often >100 nevi
- family history of melanoma
153
Keratocanthoma often mimics
squamous cell skin cancer
154
Classic description/course of keratocanthoma
- rapid onset
- grows to full size in 1-2 months
- fleshy lesion with central crater with keratinous material
155
Classic locations for keloid
upper back, chest, deltoid
156
Classic appearance of basal cell skin cancer
- shiny purple
- grows slowly
- umbilicated center
- often later ulcerates
- peripheral telangeictasias
157
Shiny purples slow growing lesion =
basal cell cancer
158
Metastatic tendency of basal cell carcinoma
almost never
159
Risks for basal cell carcinoma
- sunlight
| - light skinned
160
Features of actinic keratoses
hard, sharp, red, scaly
161
Hard sharp red scaly lesion in sun exposed area =
actinic keratoses
162
If a burn scar becomes nodular, warty or ulcerated, think_____
squamous cell cancer
163
Squamous cell cancer may have pre-cursor _____ lesions
actinic keratoses
164
Squamous cell skin cancer is also known as
Bowen disease
165
Actinic keratoses is precursor lesion of
squamous cell cancer
166
Best and worst prognostic types in melanoma
- best: superficial spreading
| - worst: nodular
167
Black dots on palms, soles or under nails =
melanoma
168
Prognosis in melanoma is related to
vertical depth on invasion
169
Kaposi sarcoma is classically associated with
AIDS
170
Paget disease of the nipple, must rule out
breast adenocarcinoma
171
Classic nutritional cause of stomatitis
- B-complex vitamins
| - Vitamin C
172
What are the main B-complex vitamins (deficiency may cause stomatitis)
- riboflavin
- niacin
- pyridoxine
