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Flashcards in Auto-immune disease Deck (62):
1

Sjogren's syndrome pathophysiology

lymphocytic infiltration of exocrine glands (esp, lacrimal and salivary)

2

Sicca Syndrome

dry eyes
dry mouth
nasal and pharygneal dryness
vaginal dryness
chronic bronchitis
reflux esophagitis
NO ARTHRITIS (as in Sjogren's)

3

Sjogren's syndrome symptoms

classic triad
xerophthalmia = dry eyes, conjunctivitis, "sand in my eyes"
xerostomia = dry mouth, dysphagia
arthritis

4

Sjogren's syndrome PE

parotid enlargement
increased risk B-cell lymphoma
dental caries
autoantibodies to ribonucleoprotein antigens: SS-A (Ro) , SS-B (La)

5

Sjogren's syndrome epidemiology

affects females between 40 and 60 YO
associated with RA

6

Systemic Lupus Erythematosus (SLE) epidemiology

90% female between 14-45 YO
most common and sever in black females

7

SLE symptoms

fever
fatigue
weight loss
Libman-Sacks endocarditis (verrucous, wart-like, sterile vegetations on both sides of valve)
hilar adenopathy
Raynaud's phenomenon

8

SLE diagnostic criteria

4 of 11 symptoms
immunoglobulins (anti-dsDNA, anti-Sm, antiphospholipid)
malar rash
discoid rash
antinuclear antibody
mucositis (oropharyngeal ulcers)
neurologic disorders
Serositis (pleuritis, pericarditis)
hematologic disorders
arthritis
renal disorders
photosensitivity

9

antiphospholipid antibodies

against phospholipids on surface of cells
protein C and prothrombin can be affected =
becomes HYPERCOAGULABLE (arterial and venous clots)
prolonged PTT
"lupus anticoagulant" or anti-cardiolipin antibody

10

mixing study

if PTT does not correct with mixing study --> diagnosis of antiphospholipid antibodies (SLE)
correction of PTT = missing clotting factor (ex: hemophilia)

11

common cause of mortality with SLE

nephritis
-diffuse proliferative glumerulonephritis (if nephritic)
membranous glomerulonephritis (if nephrotic)
etiology = immune complex deposition in the kidney
histo: wire loop glumerular lesions seen on histology

12

SLE lab findings

false positive syphilis tests (RPR or VDRL assays) - caused by antiphospholipid antibodies
-cross react with cardiolipin used in tests

13

SLE antibody tests

ANA (antinuclear antibodies) = sensitive, primary screening, not specific for SLE
anti-dsDNA Abs = very specific, poor prognosis
anti-Smith (anti-Sm) Ab = very specific, but not prognostic
antihistone Abs = mores sensitive for drug induced lupus
anti-phospholipid Ab = (lupus anticoagulant, anti-cardiolipin Abs)

14

drug induced Lupus

anti-histone antibodies - mores sensitive
Hydralazine
Procainamide

15

anti-double stranded DNA

very specific for SLE
poor prognosis

16

antinuclear Abs (ANA)

sensitive (primary screening)
not specific for SLE

17

anti-Smith antibodies

very specific
not prognostic

18

anti-histone antibodies

more sensitive to drug induced lupus
ex: Hydralazine & Procainamide

19

Sarcoidosis pathophysiology

immune mediated, widespread, noncaseating (non-necrotic) granulomatous inflammation causing ongoing inflammation and organ dysfunction
elevated serum ACE levels

20

Sarcoidosis presentation

often asymptomatic except for enlarged lymph node

21

chest x-ray findings

bilateral hilar adenopathy or reticular opacities

22

sarcoidosis PE findings

associated with restrictive lung disease (interstitial fibrosis), erythema nodosum, Bell's palsy, epithelial granulomas containing microscopic Schaumann and asteroid bodies, uveitis and hypercalcemia

23

cause of hypercalcemia in sarcoidosis

elevated 1alpha-hydroxylase- mediated vit D activation in epitheliod macrophages

24

sarcoidosis treatment

steroids

25

sarcoidosis histological findings

widespread non-caseating granuloma formation
giant multinucleate cells
lymphocytes
microscopic Schaumann and asteroid bodies
poorly circumscribed nodule

26

polymyalgia rheumatica

systemic inflammatory disorder
no muscle inflammation
patients > 50 YO
more common in women
associated with temporal (giant cell) arthritis

27

polymyalgia rheumatic signs & symptoms

pain and stiffness in the shoulders and hips (feels like proximal muscle pain, NO muscle weakness)
fever
malaise
weight loss

28

polymyalgia rheumatica lab values

normal creatinine kinase (CK) levels
increased erythrocyte sedimentation rate (ESR)

29

polymyalgia rheumatica tx

prednisone - rapid response to low-dose coritcosteroids

30

polymyositis features

progressive symmetric proximal muscle weakness
endomysial inflammation (CD-8 T cells)
most often proximal muscles affected (hips and shoulders)

31

polymyositis histology

endomysial inflammation (CD-8 T cells) within muscle fibers

32

polymyositis etiology

CD8 T cell injury to myofibers

33

polymyositis labs

increased creatinine kinase levels

34

endomysial inflammation

polymyositis
wispy layer of areolar connective tissue that ensheaths each individual muscle fiber. It also contains capillaries, nerves, and lymphatics

35

dermatomyositis characteristics

inflammation of multiple muscle groups
proximal muscle groups affected (hips and shoulders)
perivascular (perimysial) inflammation, within muscle fibers

36

perimysial inflammation

dermatomyositis
= sheath of connective tissue that groups muscle fibers into bundles (anywhere between 10 to 100 or more) or fascicles
around blood vessel supplying the muscle fibers

37

dermatomyositis labs

increased creatinine kinase levels
increased aldolase levels

38

dermatomyositis sign and symptoms

heliotrope rash
malar rash (similar to SLE)
shawl and face rash
Gottron's papules
mechanics hands = rough callused appearing hands

39

dermatomyositis risks

increased risk of malignancy (colon and ovarian cancers)

40

dermatomyositis histology

perimysial inflammation (around the blood vessels supplying muscle) and atrophy with CD4+ T cells

41

dermatomyositis lab values

increased creatinine kinase
positive ANA
positive anti-Jo-1 (very specific

42

dermatomyositis treatment

steroids to reduce inflammation

43

myastenia gravis

NMJ disorder (most common)
autoantibodies to postsynaptic ACh receptor = binds to and inactivates the receptor

44

myastenia gravis symptoms

muscle weakness that worsens with prolonged use
typically affects the facial muscles

45

myastenia gravis signs

ptosis, diplopia
extraocular muscle weakness
respiratory muscle involvement

46

myastenia gravis diagnostic tests

electromyography = repetitive nerve stimulation testing shows progressive DECREASE in action potential size of affected muscle groups
edrophonium (AChE inhibitor) = improves symptoms

47

associated complications with myastenia gravis

thymoma (tumor of the thymus)
thymic hyperplasia

48

Lambert-Eaton syndrome etiology

antibodies against the presynaptic calcium channels of the NMJ
DECREASED ACh release with neuronal transmission - block Ca influx = prevents Ca activation of ACh release in NMJ

49

Lambert-Eaton syndrome signs and symptoms

proximal muscle weakness that IMPROVES with repeated use
AChE inhibitors = NO EFFECT (problem with ACh released in NMJ)

50

Lamber-Eaton associations

associated with malignancy - occurring as a paraneoplastic syndrome (small cell lung cancer)

51

Lambert-Eaton syndrome diagnostic tests

Electromyography: repetitive nerve stimulation testing = progressive INCREASE in AP size of affected muscle groups
Edrophonium test = NO EFFECT

52

Scleroderma

progressive systemic sclerosis - excessive fibrosis and collagen deposition throughout the body
commonly sclerosis of skin = puffy and taut skin with absent wrinkles
sclerossi fo renal, pulmonary (most likely cause of death), cardiovascular, and GI systems
75% female

53

diffuse scleroderma

excessive fibrosis and collagen deposition throughout the body
rapidly progressive
sites of involvement = skin (thick/leathery), visceral organ involvement, lungs (interstitial lung fibrosis = common cause of death)

54

etiology of diffuse scleroderma

anti scl-70 antibodies against topoisomerase 1

55

CREST syndrome

limited scleroderma
Calcinosis
Raynauds phenomenon
Esophageal dysmotility
Scelrodactyly
Telangiectasia
limited skin involvement, confined to fingers and face
more benign clinical course

56

CREST lab tests

anti-centromere antibodies

57

TNF alpha inhibitors

TNF-alpha = important inflammatory mediator

58

etanercept

recombinant form of TNF receptor that binds TNF
use: RA, psoriasis, ankylosing spondylitis

59

infliximab

anti-TNF antibody
decreases the net effect of TNF-alpha
use: RA, Crohns, Ankylosing spondylitis
RISKs: predisposition to reactivation of infections (TB)

60

Adalimumab

anti-TNF antibody
use: RA, psoriasis, ankylosing spondylitis

61

fibromyalgia

most common in women 20-50 YO
chronic, widespread musculoskeletal pain associated with stiffness, parestesia, poor sleep and fatigue

62

myositis ossificans

metaplasia of skeletal muscle to bone following muscular trauma
most often seen in upper or lower extremity
may present as suspicious "mass" at site of known trauma or as incidental finding on radiography
x-ray = heterotropic ossification of elbow after injury