Patho of Joints

Question 1

What are 2 important characteristics of normal joint function?

Answer 1

Stability and lubrication

Question 2

What is the cartilage covering joint surfaces called?

Answer 2

Articular cartilage

Question 3

Does Articular cartilage have blood supply?

Answer 3

No

Question 4

What cells produce proteins and hyaluronic acid in synovial membrane?

Answer 4

Synoviocytes

Question 5

What are acute phase reactants?

Answer 5

Proteins that are used as an indicator of infectious dz and inflammatory states

Question 6

Which Acute phase reactant increases by 50% in response to inflammatory stimuli

Answer 6

Complement C3 and C4

Question 7

Which APR inc 2-4 fold in response to inflammation

Answer 7

a1-antitrypsin, fibrinogen

Question 8

Which APR inc > 1000 fold in response to inflammation?

Answer 8

C-reactive protein

Question 9

What does a low ferritin level suggest?

Answer 9

pt is iron deficient

Question 10

What happens to ferritin levels in inflammatory dz?

Answer 10

increases

Question 11

Does C-reactive protein reflect the level of inflammation directly or indirectly?

Answer 11

Directly. ESR is an indirect measure of imflammation

Question 12

What is the ESR?

Answer 12

Erythrocyte sedimentation rate. Distance column of blood falls in one hour is recorded. Rate increases w/ more inflammation.

Question 13

Explain how ESR increases w/ inflammation?

Answer 13

Red cells contain neg charged sialic acid which act to repel other RBCs. Fibrinogen and gamma globulins affect the quantity of this force and allow rouleaux to form, causing faster settling.

Question 14

What are the 3 main causes of an extremely elevated ESR ( >100)?

Answer 14

infection, malignancy, temporal arteritis

Question 15

What does loss of albumin do to the ESR?

Answer 15

Increases it. This signifies nephrotic syndrome

Question 16

What does normal joint fluid look like?

Answer 16

viscous and appears clear to light yellow

Question 17

Normal synovial fluid contains how many cells? What type of cells?

Answer 17

< 60-180 per ml. Most mononuclear

Question 18

What level of leukocytes is considered septic arthritis?

Answer 18

> 100,000

Question 19

When are Gram stains positive?

Answer 19

approx 75% of pts w/ staph infections. 50% w/ gram neg

Question 20

What color is the clarity in inflammatory?

Answer 20

yellow-green.

Question 21

What does the definitive ifentification of crystals require?

Answer 21

addition of a first order red compensator. Alters the light passage into slow and fast components.

Question 22

Positive birefringence

Answer 22

crystals blue parallel to arrow and yellow perpendicular

Question 23

MSU crystals appear how?

Answer 23

negatively birefringent needle shaped crystals

Question 24

Negative birefringence?

Answer 24

Yellow parallel, blue perpendicular

Question 25

Urates appear how?

Answer 25

neg birefringent. Seen as needles.

Question 26

Ca pyrophosphate appears how?

Answer 26

geometric shaped and weakly positive

Question 27

What is considered hyperuricemia?

Answer 27

above 6 mg/dL

Question 28

What do most assays detect with Rheumatoid factor?

Answer 28

IgM antibody that is directed against the Fc portion of IgG

Question 29

What is rheumatoid factor most useful for?

Answer 29

Prognostic indicator in patients with RA

Question 30

What antibodies are highly specific for rheumatoid arthritis?

Answer 30

anti-cyclic-citrullinated peptide (Anti-CCP)

Question 31

what is citrullination?

Answer 31

post translation modification to AA arginine and may occur in inflammatory settings

Question 32

What is the frequency of positivity on ANA screening test with a pt with RA?

Answer 32

40-60%

Question 33

What does negative ANA suggest?

Answer 33

connective tissue dz is unlikely

Question 34

How high do the titers need to be to make ANA more meaningful?

Answer 34

1:160

Question 35

What is the major target in osteoarthritis?

Answer 35

Articular cartilage (chondrocytes)

Question 36

What two mediators amplify the perpetuation of cartilage damage?

Answer 36

IL-1B and TNF-a

Question 37

How does mechanical stress initiate altered metabolism?

Answer 37

release of enzymes (MMPs, PGE2, proinflammatory cytokines)

Question 38

What are the early changes in OA?

Answer 38

degeneration of hyaline cartilage of articular surface, fragmentation of cartilaginous matrix.

Question 39

What are later changes in OA?

Answer 39

thinning of cartilage and overgrowth of apposing joint surface.

Question 40

What should you expect at time of resection?

Answer 40

expect sloughing of cartilage, bone eburnation, joint mice, cysts, and osteophytes.

Question 41

What are osteophytes?

Answer 41

bony outgrowths at margins of articular surface

Question 42

So what are the 5 steps in progression of osteoarthritis?

Answer 42

Bone, Cartilage, thinning of cartilage, cartilage remnants, destruction of said cartilage

Question 43

What is eburnation?

Answer 43

friction smoothes and burnishes the exposed bone to resemble ivory

Question 44

What is a secondary reparative response by lateral bone and cartilage?

Answer 44

osteophytes

Question 45

What are Heberden nodules?

Answer 45

Distal interphalageal joint swelling

Question 46

What are Bouchard

Answer 46

PIP swelling

Question 47

What joints are involved in OA?

Answer 47

weight bearing joints. (spine, hips, fingers, knees, feet

Question 48

Which areas in the hand are affected by OA?

Answer 48

DIP, first carpometacarpal joint, scaphotrapezial joint. PIP maybe.

Question 49

What does the RA process primarily affect?

Answer 49

The lining of the joints (synovial membrane)

Question 50

What is the anatomy of the normal joint space?

Answer 50

Synovium and articular cartilage

Question 51

What is RA pannus?

Answer 51

mass of synovium and synovial stroma consisting of inflammatory cells, granulation tissue, and fibroblasts.

Question 52

What are rice bodies?

Answer 52

accumulation of neutrophils in synovial fluid and surface

Question 53

Which hand joints does RA tend to involve?

Answer 53

PIP and MCP joints and all compartments of the wrist.

Question 54

What does the synovial fluid in RA look like?

Answer 54

neutrophils, high protein content, low mucin content

Question 55

What directions do the wrist and digits deviate in RA?

Answer 55

wrist: radial deviation, digits: ulnar deviation

Question 56

What is a rheumatoid nodule?

Answer 56

central area of necrosis rimmed by fibroblasts surrounded by capsule. Found on extensor surfaces or pressure points.

Question 57

What are common sites of rheumatoid nodules?

Answer 57

olecranon, proximal ulna

Question 58

The production of what 2 cytokines is central to inflammation?

Answer 58

IL-1 and TNF-a

Question 59

What is IL-1 responsible for?

Answer 59

Stimulating prostaglandin E2

Question 60

What is TNF-a do?

Answer 60

key in activating matrix proteinases.

Question 61

What contributes to the systemic features of the dz?

Answer 61

IL-6

Question 62

Elaboration of what cytokine is likely to explain selective recruitment of neutrophils to synovial cavity?

Answer 62

IL-8

Question 63

What do neutrophils do in the synovial fluid?

Answer 63

Release oxygen-derived free radicals that depolymerize hyaluronic acid and inactivate edogenous inhibitors of proteases.

Question 64

Difference btw OA and Ra?

Answer 64

OA: thinned cartilage, bone ends rub together. RA: swollen inflamed synovial membrane, bone erosion

Question 65

What HLA is associated with seronegative spondyloarthropathies?

Answer 65

HLA-B27 positive. Males

Question 66

Explain the bent-over posture in ankylosing spondylitis

Answer 66

As progression, new bone forms. Bone bridges the gap between vertebrae and fuses together. Flatten natural curves of spine, force it into a hunched position.

Question 67

What is affected first in psoriatic arthritis?

Answer 67

fingers and toes first. Sausage appearance.

Question 68

What is septic arthritis due to?

Answer 68

MRSA

Question 69

What is the triad for Reiter syndrome?

Answer 69

can't pee, can't see, can't climb a tree

Question 70

What is the organism that causes lyme dz?

Answer 70

B. burgdorferi

Question 71

What type of joints does Lyme dz affect?

Answer 71

large joints (knees, shoulders, elbows)

Question 72

what is gout?

Answer 72

transient attacks of acute arthritis initated by crystallization of urates around joints

Question 73

What can hyperuricemia be due to?

Answer 73

overproduction (10%) or reduced renal excretion (90%).

Question 74

How do you overproduce uric acid?

Answer 74

increased nucleic acid turnover, HGPRT mutation (decreased recycling of precursors) = Lesch-Nyhan

Question 75

What is pseudogout?

Answer 75

Calcium pyrophosphate crystal deposition disease. AD d/t mutation in ANKH gene

Question 76

Talk about the inflammation stage in gout

Answer 76

Deposition of MSU in joints is phagocytosed and activates inflammation cytokines such as IL-1B. Recruit and activate neutrophils.

Question 77

Retrace figure 26-47 in gout

Answer 77

Hyperuricemia -> precipitation of MSU in joints -> complement activation -> neutrophil chemotaxis -> phagocytosis -> release of LTB4

Question 78

How is gout definentally diagnosed?

Answer 78

demonstration of urate crystals in aspirated synovial fluid

Question 79

What is podagra?

Answer 79

gout involving the big toe

Question 80

what joints are most affected by gout?

Answer 80

big toe, ankle, instep of foot, knee, elbow

Question 81

What are the 4 stages of gout?

Answer 81

1) acute arthritis: dense neutrophilic infiltrate in synovium 2) chronic tophaceous arthritis: erosions/fibrosis w/ increased inflammatory infiltrates 3) Tophi: masses of urates, crystalline or amorphous 4) gouty nephropathy: renal medullary MSU deposition

Question 82

What is the age group and sex of pts that get gout?

Answer 82

males > females 30-50

Question 83

How do crystals appear in gout on bifringence?

Answer 83

negative birefringence. yellow parallel and blue perpendicular.

Question 84

Where do you see tophaceous deposits?

Answer 84

ear, elbow, and in/around joints

Question 85

What areas are affected by pseudogout?

Answer 85

radiocarpal joint and MCP

Question 86

how does pseudogout look on birefringence?

Answer 86

weakly positive rhomboid shaped