MSS4 Flashcards
What are the signs and symptoms of gout?
Gout: metabolic disocer result in elevation of uric acid ( usually due to underexcretion). Sx d/t deposition of monosodium urate crystals in joints. Acute gout presents as painful arthritis of great toe (podagra). Chronic gout leads to development of tophi (white, chalky depositions)
Aspiration of joint fluid shows needle shaped crystals that show negative birefringence under polarized light. What is this indicative of?
Gout
Aspiration of joint fluid shows needle shaped crystals that show positive birefringence under polarized light. What is this indicative of?
psuedogout caused by deposition of pyrophosphate dihydrate (CPPD). Usually occurs in larger joints (knee, wrist, shoulder)
What does tophaceous gout look like on xray?
Punched out bone lesions and overhanging edges
What are the signs and symptoms of CPPD?
CCPD: unknown cause, but related to overproduction of Ppi.
Hx: Attacks of acute arthritis
Labs: Fe: hemochromotosis, ALP: hypophosphatasia, Mg: hypo, Ca: hyperparathyroidsm
Joint aspiration: rhomboid shaped crystals that are positively birefringent
What are the signs and symptoms of Rheumatoid arthritis?
Hx: gradual onset of joint pain, swelling and inflammation of greater than 6 weeks in >3 joints. Symmetrical. Morning stiffness >1 hour that improves with activity. Involves PIP, wrist, elbows, knees. Spares DIP. Baker’s cyst
Exam: rheumatoid nodules (central zone of necrosis surrounded by Palisaded epitheliod histiocytes), Radial deviation of MCP, PIP (swan neck deformity)
Lab: Rheumatoid factor (IgM to Fc portion of IgG)
xray: erosion of bone
What is rheumatoid arthritis?
RA is an inflammatory polyarthritis. Pathology: chronic papillary synovitis thata results in chronic inflammation of the joint. Hyperplastic inflammated synovium forms a pannus that fills joint space.
What is osteoarthritis?
OA is a non-inflammatory polyarthritis
-Progressive disorder of the joints caused by gradual loss of cartilage
Pathology: Fibrillation and cracking of cartilage matrix, decrease new matrix formation, subchondral sclerosis (dense bone where cartilage is missing), osteophyte formation
Heberden: DIP
Bouchard: PIP
What are the signs and symptoms of osteoarthritis?
Hx: short lasting stiffness (gelling) after inactivity. Pain exacerbated by movement and use, crepitus, joint locking, morning stiffness <30 min
Pain relieved with rest
Exam: swelling around joint, crepitus, restricted ROM, weakness or wasting of muscles on joint, deformities, nodes, squaring of 1st CMC, Hallux valgus, Genu varus, Genus valgus
xray: narrowing of joint space, osteophytes, subchondral bone changes
What are some causes of OA?
Primary: imbalance in cytokine loss and growth factor resulting in matrix loss and degradation (risk factors: Female, age, trauma, obesity)
Secondary: Post traumatic, other joint disease, CPPD, gout, congenital disease, Metabolic, neuropathic
What are the strategies to treat acute and chronic gout? What are some major side effects?
Colchicine: inhibit neutrophil activation ( decrease inflammation); significant GI side effects, CYP3A4 or P-gp inhibitors contraindicated [ACUTE]
Allopurinol: blocks XO in uric acid biosynthesis. Adverse: hypersensitivity reaction. [CHRONIC]
Febuxostat: blocks XO. Adverse: higher CV side effects
Pegloticase: uricase that converte uric acid to water soluble metabolite. Adverse: infusion site rxn, gout flare. [CHRONIC]
Probenecid: uricosuric agent (competes w/ URAT 1/OAT) Adverse: GI and NOT for use in pts w/renal insufficiency. [CHRONIC]
What are the mechanisms and side effects of drugs used to treat Rheumatoid arthritis?
DMARDS: diesase modifying anti-rheumatics
- Etanercept: anti-TNF R agonist (injection site rxn, inc. risk for infections)
- Adalimumab: Binds to soluble and transmembrane forms of TNF
- Tocilizumab: binds to soluble and membrane forms of IL6 receptors (alterations in lipid profile)
- Tofacitinib: JAK stat inhibitor (prevents gf mediate gene expression)- CYP metabolism/ incr. cholesterol
- anakinra: blocks IL1 Receptor
-abatacept: inhibits T cell activation
-rituximab: antibody directed against CD 20 on B cells
What are some clinical signs of inflammatory arthritis?
Hx: morning stiffness >1 hr
Exam: erythema and warmth; synovitis
Labs: CRP, ESR, leukocytosis, (WBC >2000), joint fluid analysis
Xray: erosions of bone at joint margins
