Arthrocentesis & Joint injections Flashcards
What is the primary activated cell type in autologous conditioned serum
Monocytes
What cytokine is abundant in ACS
IL-1ra
What is the primary mechanism by which autologous conditioned serum exerts a therapeutic effect in a joint space
inhibition of inflammatory cascade
What condition is most studied for autologous conditioned serum
OA
Relationship between protein content in synovial fluid and serum
1/3 of protein content to serum
What does increased synovial protein content indicate
Inflammatory process
What is normal synovial glucose level
No lower than 10 mg/dL less than serum
What condition is associated with increased uric acid
Gout
What form of lactic acid is produced by bacteria
D-lactate
What is the role of rapid lactic acid testing in urgent care
Rapid distinction between septic and non-septic arthritis
What is RF
Ab to Ig
What is the role of testing RF in synovial samples
Small amount of pts have negative serum RF with positive synovial RF
What is a non-pathologic color of synovial fluid
Clear
What is expected volume to aspirate from a non-pathological knee
4 mL
What color and appearance indicates joint inflammation
yellow and cloudy
What are ochronotic shards?
Debris from joint prosthesis
What is the string test for
Qualitative measure of viscosity of synovial fluid, indirectly measures hyaluronic acid
What causes synovial fluid to clot
Damaged synovial membrane (traumatic tap), fibrinogen in fluid
What type of microbe is most commonly associated with joint infections (bacteria, virus, fungus, mycobacteria, parasite)
Bacteria
What are risk factors for septic arthritis d/t mycobacterium tuberculosis
Low SES, alcohol/IV drug abuse, immunosuppression, HIV injection
What would you expect to find in high amounts in synovial fluid with arthritis d/t mycobacteria?
Leukocytes
What test has the highest sensitivity for infection d/t mycobacterial arthritis
Synovial Cx
What organism is associated with the majority of septic arthritis (gram stain, shape)
Gram positive cocci
Nongonococcal arthritis associated with drug abuse, cellulitis, abscesses, endocarditis and chronic osteomyelitis is frequently d/t what 2 organisms
Gram positive staph and strep
Acute, non-traumatic, mono- or oligo- arthritis in a young, healthy, sexually active host raises the suspicion for this condition.
Gonococcal arthritis
What presentation is observed in patients presenting with gonococcal arthritis
Tenosynovitis, rash, polyarthralgia, purulent arthritis of knee/wrist/ankle
What do you do after a pt tests positive for septic arthritis d/t gonococcal infection
Test for CT, HIV, syphilis, and recommend screening partners
Within how long should cell analysis be performed on a synovial sample
1 hour
What is a general WBC differential for synovial fluid?
48 monocytes
24 lymphocytes
10 macrophages
7 neutrophils
4 synovial cells
What condition is associated with a massive increase in neutrophils
Septic arthritis
What are ragocytes
Cytoplasmic inclusions of RF within neutrophils in synovial fluid, associated with RA
What are tart cells
Monocytes with phagocytosed nonlysed nuclei of lymphocytes, seen in SLE
What factors are needed for gout dx
Acute joint inflammation, MSU crystals
What do pseudogout crystals look like
Rhombic squares
What is an ultra-filtrate?
Substance filtered by 2 barriers, ex: synovial fluid
Is joint aspiration indicated in chronic RA?
No
Joint injections are most commonly used for what condition
OA
What does platelet injection cause
Cell proliferation, growth factor and cytokine secretion
What are CI to PRP
Pregnancy, cancer, bleeding/clotting d/o
Downsides to injectable corticosteroids?
Tissue toxicity, decreased response each time, suppress body’s healing mechanisms
Which injection therapy had better effect long term in a 2006 cochrane review - corticosteroids or viscosupplementation?
Viscosupplementation
What are potential side effects of corticosteroid injections?
Infection, skin depigmentation, tendon rupture
What is viscosupplementation
Administration of synthetic hyaluronic acid
What is the proposed benefit of viscosupplementation
Stimulates production of higher quality synovial fluid
What is viscosupplementation indicated for?
Mild to moderate OA
T or F: septic arthritis is a common complication of mucosal gonococcal infection
False
