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Flashcards in Day 8.3 MSK/Derm Deck (98):
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What are the seronegative spondylo-arthropathies?

Arthritis w/o RF (sero-negative- so no anti-IgG Ab).
Strongly a/w HLA-B27 (which codes for MHC-I). More common in males.
Ankylosing spondylitis
Reactive arthritis (Reiter's)
Psoriatic arthritis

2

Ankylosing spondylitis

Chronic inflam dz of spine and sacroiliac joints leads to ankylosis (stiff spine dt joint fusion), uveitis, and aortic regurg.
Stiffness improves w (or requires) exercise
Sacroiliitis = think ank spond!
Bamboo spine - IV discs outlined by calcifications.

3

Reactive arthritis (Reiter's)

Classic triad:
1. Conjunctivitis and anterior uveitis
2. Urethritis
3. Arthritis
Can't see, pee, climb a tree
Often post-GI (shigella flexneri) or post-Chlamydia infection

4

Psoriatic arthritis

Joint pain and stiffness a/w psoriasis.
Asymmetric and patchy involvement.
Dactylitis (sausage fingers)
Pencil in cup deformity on xray.
Seen in fewer than 1/3 of pts w psoriasis

5

Rx for seronegative spondyloarthropathies

Anti-TNFa agents: Etanercept, Infliximab, Adalimumab
also NSAIDs and steroids can be used.

6

SLE lab results

ANA+ (anit-nuclear Ab. good screening test, but not specific for SLE)
Anti-dsDNA Ab (esp for renal dz. poor pgx)
Anti-Smith Ab
Anti-histone Ab (for drug-induced)

Also, will have false-pos VRDL for syphilis dt anti-phospholipid Ab, which cross-react w cardiolipin (aka anti-cardiolipin Ab)

7

SLE epi and sx

Black Female, 14-45 yo
Fever, fatigue, weight loss
non-bacterial verrucous endocarditis
hilar adenopathy
Raynaud's
Wire-loop lesions in kidney w immune complex deposition (usu nephritic syndr)
Death from renal failure and infections.

8

Causes of drug-induced SLE

SHIPP:
Sulfonamides
Hydralazine
INH
Phenytoin
Procainamide

9

SLE: I'M DAMN SHARP sx

Immunglobulins (anti-dsDNA, anti-Sm, antiphospholipid)
Malar rash

Discoid rash
ANA+
Mucositis (oropharyngeal ulcers)
Neurologic disorders (seizure, psychosis)

Serositis (pleuritis, pericarditis)
Hematologic disorders (anemia, leukopenia, lymphopenia, thrombocytopenia)
Arthritis
Renal disorders
Photosens

10

Things that can give ANA+

SLE
Sjorgren's (and sicca)
Scleroderma
Polymyositis
Dermatomyositis
RA
Juvenile arthritis
MCTD

11

Rx for SLE

Glucocorticoids
NSAIDs
Hydroxy-chloroquine (anti-malarial)
Cyclophosphamide

12

Sarcoidosis

Immune-mediated non-caseating granulomas that are widespread, plus elevated serum ACE levels.
Common in black females.

A/w GRAIN:
Gammaglobulinemia
Rheum arthritis
ACE increase
Interstitial fibrosis
Non-caseating granulomas
and
Restrictive lung dz
Bilateral hilar lymphadenopathy
Erythema nodosum
Bell's palsy
epithelial granulomas containing Schaumann and asteroid bodies
Uveopartotitis
Hyper-calcemia (d.t elevated Vit D, which is converted a lot to its active form in epitheloid macrophages.

Rx: Steroids

13

What is erythema nodosum?

Painful, nodular inflam of subcutaneous fat, classically on the anterior shin (in front of tibia)
Seen in sarcoidosis

14

What is polymyalgia rheumatica?

Pain/stiffness in shoulders and hips, often w fever, malaise, weight loss.
Despite the name myalgia, it does NOT cause muscular weakness.
Occurs in pts >50yo
A/w temporal (giant cell) arteritis

Findings: elevated ESR and normal CK (aka CPK), a marker for muscle cell breakdown

Rx: Prednisone (steroids)

15

What are the findings and Rx for polymyositis and dermatomyositis?

Increased CK, increased aldolase
Positive ANA
Anti-Jo1 Ab

Rx: steroids

16

Polymyositis

progressive symmetrical proximal musc weakness caused by CD8+ T-cell induced injury to myofibers.
Most often involves shoulders (and pelvis)- most musc dz affects proximal musc, whereas nerve dz affects distal.
Dx by musc biopsy showing evidence of inflam

17

Dermatomyositis

Like polymyositis (symm proximal musc weakness d.t CD8+ injury to myofibers)
But also involves malar rash, heliotrope rash (around eyes), shawl-and-face rash, Gottron's papules, mechanic's hands.
Increased risk of malignancy (the normal neoplasms- lung, breast, etc)

18

Myasthenia Gravis

Most common NMJ disorder.
Auto-Ab to the post-synaptic ACh receptor
Causes ptosis, diplopia, general weakness
A/w thymoma
Sx get worse (!) w musc use
Rx: AChE inhibitors (cause ACh to stay around longer)

19

Lambert-Eaton syndrome

NMJ dz
Auto-Ab to presynaptic Ca2+ channel, results in decreased ACh release, so proximal musc weakness.
Unlike MG, extraocular musc are spared.
Assc w paraneoplastic dz (sml cell lung cancer)
Sx improve w musc use (test: isometric contraction improves musc strength)
No reversal of sx w AChE inhibtors alone.

So: dry mouth + impotence + muscle weakness, and assoc w sml cell lung carcinoma = lamb-eaton

20

Mixed CT Dz

Raynaud's FAME:
Raynaud's
Fatigue
Arthralgias
Myalgias
Esophageal hypomotility

Ab to U1RNP
Responds to steroids

21

Scleroderma
aka PSS- progressive systemic sclerosis

Excessive fibrosis and collagen deposits thru-out body.
Commonly in skin- puffy taut skin w no wrinkles
There is also sclerosis of renal, pulm, CV, and GI systems
75% female.
"bulking" dz
2 types= diffuse and CREST

22

Diffuse scleroderma

widespread skin involvement, rapid progression, early visceral involvement.
Anti-Scl-70 Ab (aka Anti- DNA topoisomerase I Ab)

23

CREST scleroderma

CREST:
Calcinosis (subepithelial Ca2+ deposits)
Raynaud's
Esophageal dysmotility
Sclerodactyly (sausage fingers)
Telangiectasia

Limited skin involvement- confined to fingers and face.
More benign than diffuse.
Anti-Centromere Ab

24

Lipoma

Benign
Soft, well-encapsulated fat tumor
Cure by simple excision

25

Liposarcoma

Malignant fat tumor; can be very lg.
Will recur unless absolutely all of it is removed

26

Rhabdomyoma

Benign tumor derived from striated musc (either skeletal or cardiac)
Cardiac rhabdomyoma is common in tuberous sclerosis

27

Rhabdomyosarcoma

Malignant
Most common soft tsu tumor of childhood
Arises from skel musc, most often in head/neck

28

Derm:
Macule
Patch

Both macules and patches are flat lesions
Macule - flat discoloration 1cm
Ex: tinea versicolor

29

Derm:
Papule
Plaque

Both papules and plaques are elevated lesions
Papule - elevated and 1cm

Papule: acne vulagris
Plaque: psoriasis

30

Derm:
Vesicle
Wheal
Bulla

These are blisters
Vesicle- sml fluid containing blister (chickenpox)
Wheal - transient vesicle (hives)
Bulla - lg fluid containing blister (bullous pemphigoid)

31

Derm: Keloid

Irregular raised lesion resulting from scar tsu hypertrophy.
Follows trauma to skin, esp in african americans.
Basically just excess collagen- too much scarring.
Often on upper chest, ear lobe.
Ex: T. perenue (yaws)
Rx inject local steroids

32

Derm:
Pustule
Crust

Pustule - blister containing pus (impetigo)
Crust- dried exudate from a vesicle, bulla, or pustule

33

Derm:
Hyperkeratosis
Parakeratosis

Hyperkeratosis: increased thickness of the stratum corneum (psoriasis)

Parakeratosis: hyperkeratosis w retention of nuclei in the stratum corneum (also psoriasis)

34

Derm:
Acantholysis
Acanthosis

Acantholysis: separation of epidermal cells (pemphigus vulgaris)

Acanthosis: epidermal hyperplasia d/t increased spinosum layer (acanthosis nigricans)

35

Dermatitis

Inflam of the skin

36

Skin disorders: Verrucae

Warts
Soft tan cauliflower-like lesions
Epidermal hyperplasia, hyperkeratosis, koilocytosis
Verucca vulgaris on hands
Condyloma acuminatum on genitals (caused by HPV)

37

Skin disorders: Nevocellular nevus

common mole. benign

38

Skin disorders: Uticara

Hives
Intensely pruritic wheals that form after mast cell degeneration

39

Skin disorders: Ephelis

Freckle.
Normal number of melanocytes, but increased melanin pigment

40

Skin disorders: atopic dermatitis (aka eczema)

Pruritic eruption, commonly on skin flexures (eg anticubital fossa of knee)
Often a/w other atopic dz (asthma, allergic rhinitis)
Common px: kids <1yo getting bathed too frequently.

41

Skin disorders: allergic contact dermatitis

Type IV HPS
Follows exposure to allergen- eg nickel, poison ivy
Lesions occur at site of contact

42

Skin disorders: psoriasis

Papules and plaques (elevated) w silvery scaling (!), esp on knees and elbows.
Acanthosis (spinosum hyperplasia) with parakeratotic scaling (nuclei still in stratum corneum)
Increased stratum spinosum, decreased stratum granulosum
Auspitz sign: bleeding spots when scales are scraped off
Can be a/w nait pitting and psoriatic arthritis

43

Skin disorders: Seborrheic keratosis

Flat, greasy, pigmented sq epithelial proliferation w keratin-filled cysts (horn cysts).
Looked "pasted on"
Lesions on head, trunk, extremities
Common benign neoplasm of ELDERLY (young ppl get moles, old ppl get seborrheic keratosis)

Sign of Leser-Trelat: sudden appearance of multiple seborrheic keratoses, indicating an underlying malignancy (eg GI lymphoid)

44

Pigment disorders: albinism

Normal melanocyte number, but decreased melanin production d/t decreased activity of tyrosinase. (melanin is made from tyrosine).

Can also be caused by failure of neural crest cell migration during devt

45

Pigment disorders: vitiligo

Irregular areas of complete depigmentation
Caused by decreased number of melanocytes

46

Pigment disorders: melasma

Hyperpigmentation a/w pregnancy (mask of pregnancy) or with OCP use

47

Infectious disorders: impetigo

V superficial skin infection
Usu from S. aureus or S. pyogenes
Highly contagious
Honey-colored crusting around lips/mouth

48

Infectious disorders: Cellulitis

Acute, painful spreading infection of dermis and subcutaneous tsu.
Usu from S. pyogenes or S. aureus

49

Infectious disorders: Necrotizing fasciitis

Deep tsu injury, usu from anaerobic bacteria or from S. pyogenes.
Results in crepitus (popping) from methane and CO2 production
Flesh-eating bacteria

50

Infectious disorders: SSSS staphylococcal scalded skin syndrome

Staph exotoxin destroys keratinocyte attachments in the stratum granulosum (only).
Px w cough, fever, generalized erythematous rash, and sloughing off of upper layers of epidermis
See in newborns and children

51

Infectious disorders: Oral Hairy Leukoplakia

White painless plaques on tongue that CANNOT be scraped off.
Caused by EBV
Occurs in HIV+ pts

52

Blistering disorders: Pemphigus vulgaris

Auto-immune: IgG Ab against desmosomes (which connect cells to cells)
aka anti-epithelial cell Ab, anti-desmoglian Ab
Can be fatal.
Immunoflurescence: Ab around cells of epidermis in reticular/netlike pattern

Acantholysis: intraepidermal bullae involving skin and oral mucosa (diagnostic)

Positive Nikolsky's sign- separation of epidermis upon manual stroking of skin

53

Blistering disorders: Bullous pemphigoid

Auto-immune. IgG Ab against hemidesmosomes (connect cell to BM).
Ab are "bullow" (below) the epidermis
Shows linear immunofluorescence.
Eosinophils w/in blisters.

Similar but less severe than pemphigus vulgaris- affects skin, but spares oral mucosa, and there is a negative Nikolsky's sign (epidermis doesn't separate on stroking)

54

Blistering disorders: Dermatitis herpetiformis

Pruritic papules and vesicles
Deposits of IgA at tips of dermal papillae
A/w celiac dz

55

Blistering disorders; Erythma multiforme

A/w infections (mycoplasma pneumoniae, HSV) and esp w drug rxns- sulfa, B-lactams, phenytoin. Also assoc w cancer and auto-imm dz.
Px: multiple types of lesions- macules, papules, vesicles, target lesions (pale center)

56

Blistering disorders; Stevens-Johnson Syndrome

Fever, bulla formation (bulla- lg fluid blister), and necrosis, with sloughing of skin.
High mortality rate.
Usu a/w adverse drug rxn

More severe form: TEN toxic epidermal necrolysis. >30% of body area is sloughing off and detaching.
Caused by seizure meds, sulfa, -cillins, allopurinol

57

Misc skin: Lichen planus

PPPP: pruritic, purple, polygonal papules
Sawtooth infiltrate of lymphocytes at dermal/epidermal jn.
Assoc w HCV

58

Misc skin: Actinic keratosis

Pre-malignant lesions caused by sun exposure.
Small rough sandpapery erythematous or brownish papules. "Cutaneous horn"
Risk of carcinoma is proportional to epithelial dysplasia.
Rx: 5-FU turns it beefy red

59

Misc skin: Acanthosis nigricans

Hyperplasia of stratum spinosum.
A.w hyperinsulinemia (cushings dz, diabetes)
if >40 w new acanthosis nigricans- visceral malignancy.

60

Msic skin: Erythema nodosum

Inflammatory lesions of subcutaneous fat, usu on anterior shins
A/w cocci, histoplasmosis, TB, leprosy, strep infections, sarcoidosis

61

Misc skin: Pityriasis rosea

"Herald patch" on trunk/back followed days later by "xmas tree" distribution.
Multiple papular eruptions, remits spontaneously. Benign.

62

Misc skin: Strawberry hemangioma vs Cherry hemanigoma

Strawberry: first few weeks of life, grows rapidly and regresses spontaneously at 5-8 yo.
Cherry- appears in 30s-40s, does not regress.

63

4 causes of acne

Hyperkeratosis
Sebum overproduction
Proliferation of Proprionibacterium acnes
Inflammation

64

How to treat acne

Proliferation of P. acnes: Benzol peroxide (1st line), erythromycin, tetracycline, topical clindamycin, sulfacetamide

Sebum overproduction: isotretinoin, spironolactone (anti-androgen), estrogens

Hyperkeratosis: Vitamin A analogs, topical retinoic acid, isotretinoin

Inflam: short term local steroid injection at lvl of lesion

65

Skin rash + proximal muscle weakness

Dermatomyocytis

66

Most common skin cancers

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

67

List skin cancers in order of metastatic potential:

1. melanoma (worst)
2. sq cell carcinoma
3. basal cell carcinoma

68

Melanoma

Skin cancer w high risk of metastasis
Dark w irreg borders.

S-100 tumor marker
a/w sunlight exposure, fair-skinned pts at incrsd risk
Depth of tumor correlates w risk of metastasis

ABCD:
Asymmetry, Border irreg, Color (diff colors w/in same lesion), Diameter (bigger than pencil eraser)

69

What is a precursor to melanoma?

Dysplastic nevus (atypical mole)

70

Basal cell carcinoma

Most common skin cancer.
Locally invasive, but usu never metastasizes.
Rolled edges w central ulceration.
Histo: palisading nuclei (nuclei line up long-ways)
Gross: pearly papules, commonly w telangiectasias

71

Squamous cell carcinoma

2nd most common skin cancer after basal cell.
A/w excessive sunlight and arsenic exposure.
Common on hands/face
Locally invasive, rarely metastasizes.
Ulcerative red lesion- erosive.
A/w chronic draining sinuses.
Histo: keratin pearls

72

Precursor to sq cell carcinoma

Actinic keratosis (sandpaper lesion)

73

Keratoacanthoma

variant of sq cell carcinoma that grows rapidly (4-6wks) and regresses spontaneously (4-8wks)
Dome-shaped, wartlike.

74

Mech of Aspirin

Irreversibly (!!) inhibits COX-1 and COX-2 by covalent binding, which causes less TXA2 and prostaglandins to be produced.

75

Aspirin clinical use

Low dose (<300mg/day): decreases plt aggregation
Med dose (300-2400mg/day): antipyretic and analgesic
High dose (2400-4000 mg/day): anti-inflam

76

Toxicity of aspirin

Gastric upset
Chronic use can lead to acute renal failure, interstitial nephritis, and upper GI bleeding.
Reye's syndrome in kids w viral infection.

77

Acetominophen mechanism

Reversibly inhibits COX, mostly in CNS. Inactivated peripherally.

78

Acetominophen clinical use

anti-pyretic, analgesic, but does not have anti-inflam properties.
use instead of aspirin in kids w viruses so they don't get reye's

79

Acetominophen toxicity

overdose causes hepatic necrosis
acetaminophen metabolite depletes glutathione and forms toxic tsu adducts in the liver.

80

What is the antidote to acetaminophen OD?

N-acetylcysteine (it regenerates glutathione)

81

What is N-acetylcysteine used for?

Antidote for acetaminophen OD
Prevents contrast-induced nephropathy
Mucolytic (breaks up mucous plugs, eg in CF, bronchial asthma)

82

What is fibromyalgia?

Excess muscular tenderness in 11/18 sites
Chronic generalized pain, fatigue, sleep disturbances, HA, cognitive difficulty, mood disturbances (30% have deprsn/anx)

83

Rx for fibromyalgia

Pregabalin, milnacipran (SNRI)
Amitryptiline (helps to sleep), low-dose analgesic, fluoxetine

Reassurance, exercise.stretching, sleep, relaxation techniques, stress reduction

84

What skin disorder has pruritic, purple, polygonal papules?

Lichen planus

85

What skin disorder has life threatening rash w bulla?

Stevens-Johnson Syndrome (and TEN)
Pemphigus vulgaris

86

What skin disorders consists of pruritis a/w asthma?

Eczema (atopic dermatitis)

87

What skin disorder has pruritic veslcles and is a.w celiac dz?

Dermatitis herpetiformis

88

What skin disorder exhibits an allergy to nickel?

Contact dermatits (type IV HPS)

89

What skin disorder results in a thickened scar esp around face.chest?

Keloids

90

What skin disorder has Ab against epidermal BMs?

Bullous pemphigoid (Ab against hemidesmosomes)

91

What skin disorder has Ab against epidermal cell surface?

Pemphigus vularis (Ab against desmosomes)

92

What skin disorder exhibits parakeratotic scaling?

Psoriasis

93

What skin disorder has keratin-filled cysts?

Seborrhic keratosis (in old pts)

94

What skin disorder is characterized by sand paper lesions and predisposes to sq cell cancer?

Actinic keratosis

95

What skin disorder exhibits skin rash w proximal musc weakness?

Dermatomyositis

96

What skin disorder features honey-crusting lesions common around the nose/lips?

Impetigo

97

What skin disorder exhibits hyperderatosis and koilocytosis?

Verruca (warts- from HPV)

98

What skin disorder shows palisading nuclei on histology?

Basal cell carcinoma