Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

USMLE STEP 1 > Derm > Flashcards

Derm Flashcards

1
Q

Layers of the Epidermis

A 
"Californians Like Girls in String Bikinis"
Stratum Corneum (keratin)
Stratum Lucidum
Stratum Granulosum
Stratum Spinosum (spines = desmosomes)
Stratum Basale (stem cell site)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Sebaceous gland
What kind of gland?
What does it secrete?
What is it associated with?

A

Holocrine (cell rupture) secretion of sebum associated with hair follicle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Eccrine gland
What does it secrete?
Where are they located?

A

Secret sweat

Found Everywhere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q 
Apocrine gland
What does it secrete?
Where are they located?
When does it begin functioning?
How are they different from eccrine glands sensory-wise? Why?
A

Secretes milky viscous fluid
Found in axillae, genitalia, and areolae
Does not become functional until puberty
Malodorous because of bacterial action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Tight Junctions
Name
Function
Composition

A

Zona Occludens
Prevents paracellular movement of solutes
Claudins and Occludins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q 
Adherens Junctions 
Name
Location
What does it form?
Composition
Association with disease?
A

Zona Adherens
Below tight junctions
Forms belt connection actin cytoskeletons of adjacent cells
CADherins (Ca dependent ADhesion proteins)
Loss of E cadherin promotes metastasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q 
Desmosomes 
Name
Function
Composition
Disease involving them?
A

Macula Adherens
Structural support
Desmoplakin and Keratin
Autoantibodies –> pemphigus vulgaris

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Gap Junctions
Composition
Function

A

Connexons (channel proteins)

Permit electrical and chemical communication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Hemidesmosomes
Function
Composition
Disease involving them?

A

Connect keratin in basal cells to underlying basement membrane
Integrins in cell bind Laminin in BM
Autoantibodies –> Bullous Pemphigoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

SLE
Epidemiology
Presentation
Common cause of death?

A

90% are female 14-45. Most common and severe in blacks
Fever, Fatigue, Wt Loss, Libman-Sacks Endocarditis, Hilar adenopathy, Raynaud Phenomenon
Nephritis is common cause of death
Nephritic: DPGN, Nephrotic: Membranous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Libman-Sacks Endocarditis

A

Verrucous wart-like sterile vegetations on both sides of valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Lab results in SLE

A

False + on Syphilis test (RPR/VDRL) due to antiphospholipid Abs which cross react with cardiolipin used in test
ANA (sensitive but not specific)
Anti dsDNA (specific, poor prognosis)
Anti Smith Ab (specific, not prognostic)
Anti Histone Ab (sensitive for drug induced lupus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Presentation of SLE

A

“I’m DAMN SHARP”
Immunoglobins (dsDNA, Smith, Phospholipids)
Malar Rash
Discoid Rash, ANA, Mucositis (oropharyngeal ulcers), Neurological disorder
Serositis (pleuritis, pericarditis), Hematologic disorders, Arthritis, Renal disorders, Photosensitivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q 
Sarcoidosis 
Epidemiology  
Findings 
Labs
Histo
A

Black females
Enlarged bilateral hilar adenopathy or reticular opacities on CXR
↑ ACE levels, ↑ Ca (elevated 1α hydroxylase mediated VitD activation in epithelioid Macs)
Noncaseating Granulomas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Sarcoidosis
Symptoms
Associated with what disease?
Treatment

A

“A Red BUG”
Often asymptomatic. Erythema Nodosum, Bell’s Palsey, Epithelial Granulomas containing microscopic Schaumann and Asteroid Bodies, Uveitis
Associated with Restrictive Lung disease (interstitial fibrosis)
Steroids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q 
Scleroderma 
Characterization
Presentation 
Other organ systems involved?
Epidemiology 
Types
A

Excessive fibrosis and collagen deposition throughout body
Commonly sclerosis of skin manifesting as puffy and taut skin w/o wrinkles
Sclerosis of Renal, Pulmonary (most common cause of death), CV, GI systems
75% females
Diffuse vs CREST

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Diffuse Scleroderma
Presentation
Progressive
Labs

A

Widespread skin involvement
Rapid progression with early visceral involvement
Anti Scl70 Ab (anti DNA topoisomerase I)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q 
CREST Syndrome 
Name
Areas involved 
Prognosis
Labs
A

Calcinosis, Raynaud’s phenomenon, Esophageal dismotility (b/c of fibrous replacement of muscularis), Sclerodactyly, Telangiectasia
Limited skin involvement (Fingers and Face)
Benign clinical course
Anti Centromere Ab

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Macule

A

Flat lesion w/ well circumscribed change in skin color

<5mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Patch

A

Macule >5mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Papule

A

Elevated solid skin lesion <5mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Plaque

A

Papule >5mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Vesicle

A

Small fluid containing blister <5mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Bulla

A

Large fluid containing blister >5mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Pustule
Vesicle containing pus
26
Wheal
Transient smooth papule or plaque (Hives)
27
Scale
Flaking off of stratum corneum
28
Crust
Dry exudate
29
Hyperkeratosis
Thickening of stratum corneum
30
Parakeratosis
Hyperkeratosis with retention of nuclei in stratum corneum
31
Acantholysis
Separation of epidermal cells
32
Acanthosis
Epidermal hyperplasia (↑ spinosum)
33
Dermatitis
Inflammation of the skin
34
Albinism What is it? Causes
Normal melanocyte # with ↓ melanin production | ↓ Tyrosinase activity or failure of neural crest cell migration during development
35
Melasma (Chloasma)
Hyperpigmentation associated with pregnancy or OCP use
36
Vitiligo
irregular areas of complete depigmentation caused by ↓ in melanocytes
37
``` Verrucae What is it? Causes by Description PathoPhys If on genitals ```
Warts HPV Soft, tan colored, cauliflower-like papules Epidermal hyperplasia, Hyperkeratosis, Koilocytosis Condyloma Acuminatum on genitals
38
Melanocytic nevus What is it? Malignant? Location and description?
Common mole Benign but melanoma can arise in congenital or atypical moles Intradermal nevi are papular. Junctional nevi are flat macules
39
Urticaria What is it? PathoPhys
Hive | Pruritic wheal that forms after mast cell degranulation
40
Ephelis What is it? Physiology
Freckle | Normal # of melanocytes with ↑ melanin pigment
41
``` Atopic Dermatitis What is it? Common location Associated with what other diseases Course ```
Eczema. Pruritic eruptions Commonly on skin flexures Associated with other atopic disease (asthma, allergic rhinitis) Usually starts on the face during infancy and often appears in the antecubital fossae thereafter
42
Allergic Contact Dermatitis Type of Rxn Location
Type IV hypersensitivity reaction following exposure to allergen Lesions occur at site of contact
43
``` Psoriasis What is it? Where is it? Histo Physical Exam findings Associations ```
Papules and Plaques with silvery scaling Knees and Elbows Acanthosis with parakeratotic scaling (nuclei still in stratum corneum). ↑ Stratum spinosum, ↓ Stratum granulosum Auspitz sign (pinpoint bleeding spots from exposed dermal papillae when sclaes are scraped off) Associated with nail pitting and psoriatic arthritis
44
``` Seborrheic Keratosis What is it? Appearance Location Malignant Age of pt? ```
``` Flat, Greasy, Pigmented Squamous Epithelial Proliferation with keratin filled cysts (horn cysts) Looks stuck on Head, trunk, extremities Benign neoplasm Older persons ```
45
Leser Trelat Sign
Sudden appearance of multiple seborrheic keratoses indicating an underlying malignancy (GI, lymphoid)
46
Pemphigus Vulgaris PathoPhys If Presentation
IgG Abs against desmoglein 1 +/or 3 (part of desmosome) If reveals Abs around epidermal cells in reticular or netlike pattern Acantholysis - Intraepidermal bullae causing flaccid blister involving skin and oral mucosa. + Nikolsky Sign
47
Nikolsky Sign
Separating of epidermis upon manual stroking of skin | Means that the lesion is intraepidermal
48
``` Bullous Pemphigoid PathoPhys If Histo Presentation ```
``` IgG Abs against hemidesmosomes Linear If Eosinophils within tense border Affects skin but not oral mucosa - Nikolsky sign ```
49
Dermatitis Herpetiformis What is it? PathoPhys Associated with what disease?
Pruritic papules, vesicles, and bullae Deposits of IgA at tips of dermal papillae Associated w/ celiac disease
50
Erythema Multiforme What causes it Presentation
Infections (Mycoplasma pneumoniae, HSV), Drugs (sulfa, β lactams, phenytoin), Cancer, Autoimmune Presents with macules, papules, vesicles, target lesions (targets with multiple rings and dusky center showing multiple epithelial disruption)
51
``` Stevens-Johnson Syndrome Presentation Danger Description of lesions Caused by Severe form ```
Fever, Bulla, Necrosis, Sloughing off of skin High mortality rate Typically 2 mucus membranes are involved. Lesions may appear like targets as seen in erythema multiforme Adverse drug reaction More severe form is toxic epidermal necrolysis
52
``` Acanthosis Nigricans PathoPhys Description Location Diseases associated with it? ```
Epidermal hyperplasia causing symmetrical hyperpigmented, velvety thickening of skin Neck and axilla Hyperinsulinemia (diabetes, obesity, Cushing's) and visceral cancer
53
``` Actinic Keratosis Malignant? What causes it? Description Risk of... ```
Premalignant lesion caused by sun exposure Small, rough, scaley erythematous or brownish papules or plaques Risk of squamous cell carcinoma proportional to degree of epithelial dysplasia
54
Erythema Nodosum PathoPhys Location Associated with what disorders?
Inflammatory lesions of subcutaneous fat Anterior shins Sarcoidosis, Coccidioidomycosis, Histoplasmosis, TB, Streptococcal infection, Leprosy, Crohn's Disease
55
Lichen Planus Description Histo Associated with what other diseases?
Pruritic, Purple, Polygonal, Planar, Papules and Plaques Sawtooth infiltrate of lymphocytes at dermal-epidermal junction HCV
56
Pityriasis Rosea Course Description
Herald Patch followed days later by Christmas tree distribution. Self-resolving in 6-8 weeks Multiple plaques with collarette scales
57
Sunburn PathoPhys Kind of UV light What can in lead to?
UV irradiation causes DNA mutations inducing apoptosis of keratinocytes UVA is dominant in tanning and photoaging UVB is dominant in sunburn Can lead to impetigo and skin cancers (basal cell carcinoma, squamous cell carcinoma, and melanoma)
58
``` Impetigo What is it? What causes it? Epidemiology Presentation ```
Very superficial skin infection S aureus or S pyogenes Highly contagious Honey colored crusting
59
Bullous Impetigo
Bullae caused by S aureus
60
``` Cellulitis What is it? Presentation Caused by? Course ```
Spreading infection of dermis and subcutaneous tissues Acute and painful S pyogenes or S aureus Often starts with break in skin from trauma or another infection
61
Necrotizing fasciitis What is it? What causes it? Presentation
Deeper tissue injury Anaerobic bacteria or S pyogenes. "Flesh eating bacteria" Crepitus from methane and CO2 production Bullae and purple colored skin
62
Staphylococcal scalded skin syndrome (SSSS) PathoPhys Presentation Classic Pt?
Exotoxin destroys keratinocyte attachment in the stratum granulosum only Fever and generalized erythematous rash with sloughing of the upper layers of the epidermis that heals completely Newborns and children
63
Toxic Epidermal Necrolysis
Exotoxin destroys epidermal-dermal junction
64
Hairy Leukoplakia What is it? What causes it? What kind of pt gets it?
White, painless, plaques on the tongue that cannot be scraped off EBV HIV+ pt
65
``` Basal Cell Carcinoma Frequency Location Invasion? Metastatic? Presentation Secondary presentation? Histo ```
Most common skin cancer Sun exposed areas Locally invasive but almost never metastasizes Pink, Pearly nodules commonly w/ telangiectasias, rolled border, central crusting or ulceration Also appears as nonhealing ulcer with infiltrating growth or a scaling plaque Palisading nuclei
66
``` Squamous Cell Carcinoma Frequency What causes it? Location Invasion? Metastatic? Presentation Associated w/ Histo ```
2nd most common skin cancer Sun exposure, immunosuppression, arsenic exposure Face, lower lip, ears, hands Locally invasive but may spread to lymph nodes and will rarely metastasize Ulcerative red lesions with frequent scales Associated with chronic draining sinuses Keratin pearls
67
Keratoacanthoma
Variant of Actinic Keratosis that grows rapidly (4-6 weeks) and may regress spontaneously over months
68
``` Melanoma Metastatic? Marker? Risk factors? Presentation ```
Depth of tumor correlates with metastasis S-100 Sunlight exposure. Fair skinned persons Asymmetry, Border irregularity, Color variation, Diameter > 6mm, Evolution over time
69
Melanoma Genetics Treatment
BRAF kinase mutation. BRAF V600E is metastatic and unresectable. Excision with appropriately wide margins. BRAF V600E: use Vemurafenib or BRAF kinase inhibitors

USMLE STEP 1 (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions