Rheumatology and Dermatology Flashcards Preview

DIT Phase II Chapters > Rheumatology and Dermatology > Flashcards

Flashcards in Rheumatology and Dermatology Deck (51):
1

Nonepithelial/Nonjunctional Adhesion Mechanisms

  • Cadherins
  • ICAMs
  • Integrins
  • Selectins

2

Hemidesmosome, cadherin, integrin, ICAM-l. Which joins only cells of the same type and does not attach cells to the basement membrane? 

 Cadherins

3

Fibroblasts are involved in which tissues?

  • Stimulated by tissue damage
  • Involved in Collagen
  • Glycosaminoglycans
  • Reticular and elastic fibers
  • Glycoproteins

4

Melanocytes

  • Melanin-producing cells
  • Located in the stratum basale (bottom layer) of the epidermis
  • Responsible for skin color

5

Energy Exchange That Takes Place at the Skin

  • UV light is used to generate vitamin D
  • Melanocytes displace UV light as heat
  • Bilirubin is converted
  • Dendritic cells process antigens 
  • Mechanical energy is converted to electrical energy by nerve endings

6

Macule

Flat discoloration < 1cm (ie Tinea versicolor)

7

Patch

Macule (flat discoloration) > 1cm

8

Papule

  • Elevated skin lesion < 1 cm
  • example: Acne vulgaris

9

Plaque

  • Papule> 1 cm
  • example: Psoriasis

10

Vesicle

  • Small fluid-containing blister
  • example: Chickenpox

11

Wheal

  • Transient vesicle
  • example: Hives

12

Bulla 

  • Large fluid-containing blister
  • Example: Bullous pemphigoid

13

Keloid 

  • Irregular, raised lesion resulting from scar tissue
  • example: T pertenue (yaws)
  • Follows trauma to skin, especially in African-Americans
  • Usually upper chest

14

Pustule

Blister containing pus

15

Crust

  • Dried exudates from a vesicle, bulla, or pustule
  • Example: Impetigo

16

Hyperkeratosis

  • ↑ thickness of stratum corneum
  • Psoriasis

17

Parakeratosis

  • Hyperkeratosis with retention of nuclei in stratum corneum
  • Psoriasis

18

Acantholysis

  • Separation of epidermal cells
  • Pemphigus vulgaris

19

Acanthosis 

Epidermal hyperplasia (↑ spinosum)

20

Dermatitis

Inflammation of the skin

21

Verrucae 

  • Warts
  • Soft, tan-colored, cauliflower-like lesions.
  • Epidermal hyperplasia, hyperkeratosis,koilocytosis.
  • Verruca vulgaris on hands;
  • Condyloma acuminatum on genitals (caused by HPV 6 and 11)

22

Nevocellular nevus

  • Common mole
  • Benign

23

Urticaria 

  • Intensely pruritic wheals that form after mast cell degranulation

24

Ephelis

  • Freckle
  • Normal number of melanocytes
  • ↑melanin pigment

25

Atopic dermatitis (eczema)

  • Pruritic eruption, commonly on skin flexures
  • Often associated with other atopic diseases (asthma, allergic rhinitis)

26

Allergic contact dermatitis

  • Type IV hypersensitivity reaction that follows exposure to allergen
  • Lesions occur at site of contact

27

Atopic dermatitis (eczema) Treatment

  • Switching to a moisturizing soap (Dove, Aveeno) and adding an OTC emollient may be all that is needed for maintenance and mild cases;
  • Calcineurin inhibitors: tacrolimus (Protopic) or pimecrolimus (Elidel);
  • Topical Steroids
  • Antibiotics for open lesions (cover Staph. aureus and Strep. spp.);
  • Antihistamines
  • Leukotriene inhibitors (Montelukast) — theoretical efficacy supported by weak studies;
  • UV light therapy
  • Systemic steroids (1-2mg/kg/d in children then taper) only in severe cases and only for short duration;
  • For very severe cases, consider methotrexate, cyclosporin, azathioprine

28

Psoriasis

  • Papules aiid plaques with silvery scaling, especially on knees and elbows
  • Acanthosis with parakeratotic scaling (nuclei still in stratum corneum)
  • ↑ stratum spinosum, ↓stratum  granulosum
  • Auspitz sign (bleeding spots when scales are scraped off)
  • Can be associated with nail pitting and psoriatic arthritis

29

Acne Pathophysiology and Treatment

  • Hyperkeratosis - Isotretinoin (Vitamin A derivatives)
  • Sebum overproduction - Estrogen, Spirinolactone
  • Propionibacterium acnes proliferation - Topical - Benzoyl Peroxide, Antibiotics - Erythromycin, tetracycline, doxycycline, clyndamycin
  • Inflammation - Inject with steroids

30

A pregnant patient comes to the clinic complaining of new dark pigmentation on her face. What is the most likely diagnosis?

Melasma

31

What are some of the hallmark features of necrotizing fasciitis? What organism causes this infection?

  • Rapidly spreading cellulitis
  • Tenderness beyond red border
  • Strep pyogenes (GAS)

32

What organism causes painless white patches on the tongue that cannot be scraped off?

EBV - oral hairy leukoplakia

33

What is a lesion of excessive collagen deposition especially around the face ears, neck or upper chest called?

Keloid

34

What organism is responsible for acne vulgaris?

Propionibacterium acnes

35

Seborrheic keratosis

  • Flat, greasy, pigmented squamous epithelial proliferation with keratin-filled cysts (horn cysts)  
  • Looks “pasted on”
  • Lesions occur on head, trunk, and extremities
  • Common benign neoplasm of older persons
  • Sign of Leser-Trélat - sudden appearance of multiple seborrheic keratoses indicating an underlying malignancy (e.g., CI, lymphoid).
  • Melanoma part of DDx

36

Impetigo

  • Very superficial skin infection
  • Usually from S. aureus or S. pyogenes
  • Highly contagious
  • Honey-colored crusting

37

Cellulitis

  • Acute, painful spreading infection of dermis and subcutaneous tissues.
  • Usually from S. pyogenes or S. aureus.

38

Necrotizing fasciitis

  • Deeper tissue injury, usually from anaerobic bacteria and S. pyogenes 
  • Results in crepitus from methane and CO2 production
  • “Flesh- eating bacteria”

39

Staphylococcal scaled skin syndrome (SSSS)

  • Exotoxin destroys keratinocyte attachments in the stratum granulosum only
  • Characterized by fever and generalized erythematous rash with sloughing of the upper layers of the epidermis.
  • Seen innewborns and children

40

Hairy leukoplakia

  • White, painless plaques on the tongue that cannot be scraped off.
  • EBV mediated.
  • Occurs in HIV positive patients.

41

Blistering skin disordes

  • Pemphigus vulgaris - IgG against desomosomes, Acantholysis - intraepidermal bullae causing flaccid blister involving skin and oral mucosa, Positive Nikolsky
  • Bullous pemphiogoid - Autoimmune disorder IgG against hemidesomsomes, antibodies are "bullow" the epiidermis, Spares oral mucosa, Negative Nikolsky
  • Dermatitis herpetiformis - pruritic papules and vesicles deposits of IgA at tip of dermal papillae - celiac disease
  • Erythema multiforme - Infections (M. pneumoniae, HSV), drugs, cancer, autoimmune, macules, papules, vesicles, target lesions
  • Stevens-Johnson syndrome - Fever, bulla and necrosis, sloughing of skin, Drugs - Seizure meds, sulfa, penicillins, allopurinol.
  • TEN worse form >30% skin sloughing/necrosis

42

Lichen Planus

  • Pruritic
  • Purple
  • Polygonal
  • Papules
  • Sawtooth infiltrate of lymphocytes at the dermal-epidermal junction
  • Treat w/ 5-FU

43

Actinic keratosis

  • Premalignant lesions caused by sun exposure
  • Small, rough, erythematous or brownish papules
  • "Cutaneous horn"
  • Risk of carcionoma proportional to epithelial dysplasia

44

Acanthosis nigricans

  • Hyperplasia of stratum spinosum
  • Associated with hyperinsulinemia (Cushing's disease, diabetes)
  • Visceral malignancy

45

Erythema nodosum

  • Inflammatory lesions of subcutaneous fat
  • Usually on anterior shins
  • Associated with coccidioidomycosis, histoplasmosis, TB, leprosy, streptococcal infections, sarcoidosis

46

Pityriasis rosea

  • "Herald patch" (2-10cm oval read patch) Followed days later by "Christmas tree" distribution
  • Multiple papular eruptions
  • Remits spontaneously
  • Strawberry and cherry hemangiomas also possible

47

Most common skin cancers

  1. Basal cell carcioma
  2. Sqamous cell carcinoma
  3. Melanoma

48

Order of metastatic risk in skin cancer

  1. Melanoma
  2. Squamous cell carcinoma
  3. Basal cell carcinoma

49

Squamous cell carcinoma

  • Very common 
  • UV sunlight and Arsenic
  • Commonly appear on hands and face, lower lip
  • Rarely metastasize
  • Ulcerative red lesion
  • Associated with chronic draining sinuses
  • Histo: Keratin "pearls"
  • Actinic keratosis is precursor to SCC
  • Keratocanthoma - variant that grows rapidly (4-6 weeks) regresses spontaneously (4-8 weeks)

50

Basal Cell Carcinoma

  • Sun exposed areas
  • Upper lip
  • Locally invasive almost never matastasizes
  • Rolled edges with central ulceration
  • Pearly papules commonly with telangiectasias
  • Histo: peripheral "Palisading" nuclei

51

Melanoma

  • Common tumor with significant risk for metastasis
  • S-100 tumor marker
  • Sunlight exposure - fair skin higher risk
  • $ Depth correlates with risk of metastasis
  • Dysplastic nevus (atypical mole) is precursor
  • $ ABCDs and Hx of change - 
    • Asymmetry
    • Border irregularity
    • Color variation
    • Diameter > 6 mm