Gout RA OA Flashcards
Type 2 collagen is good for what kind of stress?
Tensile strength
What kind of cells line the synovial cavity?
What do these cells do?
cuboid cells; 1-4 layers thick
-produce synovial fluid; remove debris; regulate movement of solute, electrolytes, and proteins.
NSAIDS
- What are two good drugs to use
- When do you use it?
- when should you not use.
- What do you need to consider in terms of side effects?
- Naproxen, Indomethecin,
- Use it within 24 hours
- Do not use within 24 hours
- becareful of GI side effects
Name 3 good drug choices for acute gout attack
NSAIDs (not Aspirin), Steroids, and Colchicine
Steroids
- What is it mostly for in a case of gout attack?
- What should you be careful to do?
- It can be used for symptomatic relief when NSAIDs are not tolerated.
- Make sure it’s not used for an extended periods.
Colchicine
- mechanism of action
- when to use?
- effect on uric acid excretion
- administration method
- metabolism
- what does it interfere with? What are some implications due to this?
- side effects? severity?
- Contraindications
- Colchicine binds alpha/beta tubulin units and prevents polymerization. Therefore decreasing neutrophil recruitment and proliferation.
- Use in acute gout attacks or for prophylaxis.
- There is not effect on uric acid excretion itself
- oral admin
- Metabolized by CYP3A4
- it interferes with pglycoproteins…meaning it will interfere with other drugs that are eliminated via pglycoprotein channels.
- severe GI side effects (N/V/D/pain), because it affects rapidly overturning GI cells… and effect can be latent
- contraindications: hepatic and renal insufficiency… because this would increase concentration or prolong duration of colchicine
What are reasons for prophylaxis of gout? (5)
- frequent attacks
- very severe attacks (disabling)
- renal disease
- urate nephropathy
- tophaceous gout
What are some nonpharmacological ways to prevent gout?
- weight loss
- don’t drink alcohol
- stop taking drugs that impair uric acid excretion:
- -Asprin, thiazide diuretics, cyclosporin
List 5 medications for prophylaxis of gout
-which one is also used for acute attacks?
- Febuxostat
- Allopurinol
- Probenecid
- Pegloticase
- (Colchicine)-MOSTLY used for acut attacks
Allopurinol
- Mechanism of action
- Side effect of allopurinol (2 major; 4 minor)
- What worsens the likelihood of side effects?
- What can be done to alleviate one of the side effects?
- What are indications for allopurinol treatment?
Allopurinol is a analog of hypoxanthine. It is converted to oxipurinol by aldehyde oxidoreductase… and oxipurinol is an analog of xanthine. Therefore oxipurinol competes with xanthine in conversion to uric acid by xanthine oxidase.
- Hypersensitivity; and acute gout attack
- —-> also minor ones such as dizziness, diarrhea, HA, nausea.
- gout precipitating medications such as thiazide diuretics, ACE inhibitors and amoxicillin
- administering allopurinol with NSAIDs decreases the chance of acute gout attack via down reg of inflammation
- chronic gout/hyperurecemia (or chronic secondary conditions causing gout/hyperuricemia). Gout nephropathy, tophaceous depsitis, renal urate stones.
What is allopurinol an analog of?
What is the active form of allopurinol? What converts allopurinol to this?
What is the half life of allopurinol?
What’s the half life of the activated product?
hypoxanthine.
- Oxipurinol. Aldehyde oxidoreductase.
- Allopurinol T1/2 is 1-2 hours; Oxipurinol T1/2 is 18-30 hours
What should Allopurinol be given with? why?
Allopurinol should be given with NSAIDs to prevent acute gout attacks.
Febuxostat
- mechanism (be specific)
- Side effects
Fubuxostat is a stabilizer of xanthine oxidase in both its reduced and oxidized forms. However, it is NOT a xanthine or hypoxanthine analog.
-dizziness, HA, nausea, diarrhea
Allopurinol vs Febuxostat
- Which is more potent
- Which has less side effects? (which kind in which drug is worse?)
- Name advantages of Febuxostat (2)
- Febuxostat is more potent
- minor side effects such as nausea, diarrhea, HA, and dizziness are about the same in both
- cardiovascular side effects (antiplatelet trialists collaboration events) are worse in Febuxostat
- It is more potent and it is more effective in patients with renal disease (maybe because it’s more potent?)
What is the natural urate removing enzyme that humans lack?
What does it convert urate to?
What is a synthetic analog of this enzyme used for gout therapy?
acute or prophylactic?
Uricase
converts uric acid to allantoin (inactive water soluble metabolite)
Pegloticase
prophylactic
What is pegloticase? structurally
PEG=polyethylene glycol; covalently attached to recombinant uricase. molecule
Pegloticase
- admin
- T1/2
- side effects
- therapeutic use
- advantage?
- Disadvantage
- IV admin (every 2 weeks)
- long t 1/2
- infusion site reaction, hypersensitivity to PEG, gout flare
- good for refractory chronic gout
- advantage is it has a very long T1/2… Therefore they can get infusions every other week.
- IV infusion rather than oral is a disadvantage.
Probenecid
- effect on uric acid?
- Mechanism of action
- administration
- T1/2?
- what does it bind?
- side effects
- contraindications
- advantage?
- disadvantages
- Therapeutic uses? in which kind of patient population?
- It increases excretion of uric acid
- by blocking the organic anion transporters (OAT) and URAT1 channels in kidney tubules responsible for uric acid reabsorption.
- Oral administration
- T 1/2 dose dependent!!!
- It binds plasma proteins
- Side effects: GI discomfort.
- advantage is that it’s oral admin
- disadvantage is that it is ineffective in kidney disease patients since it affects kidneys.
- Do NOT use in pts with uric acid kidney stones
- Therapeutic use in chronic gout patients with underlying underexcretion (NOT overproduction or kidney insufficient pts)
Drug interactions:
Allopurinol/Febuxostat (2)
Colchicine
Probenecid (5)
- Decrease metabolism of thereby increasing concentrations of Azathioprine and Mercaptopurine
- decreased metabolism of and transportation of colchicine (Amprenavir, Ritonavir, AmiodaroneClarithromycin, Cyclosporine, Erythromycin); increased metabolism of colchicine (Clarithromycin, Rafampin)
- decreased renal excretion of thereby increased concentration of Clofibrate, Methotrexate, Palatrexate, Penicillin, Salicylate,
Rheumatoid arthritis
- what percent of the population is affected?
- Immunological involvement? What type of cells are involved? (very general)
- What genetic factors contribute to RA?
- Other contributions to RA.
- Pathogenesis? What does it resemble?
- 1%
- T cells (mostly) and B cells
- HLA-DR4 is often involved. It’s an over expression of shared epitopes
- Environment (smoking) and hormonal (female >male)
- invasion of immune cells in the synovium along with FIBROBLASTS (formation of pannus and granulation tissue) leads to scarring, (Synovitis) inflammation, and deformation (fibromyoblasts). joint is destryed. It resembles a benign, but locally invasive, tumor.
- What is chronic Rheumatoid arthritis called?
- What cells are involved? (4)
- What do these cells form in the joints?
- what cells and molecule are involved in the acute phase?
- What is the morphology of cells in RA? cell number? gross structure?
- What is the characterizing feature of RA? what does it do overtime? (3)
- –what is different from osteoarthritis?
- histological appearance (2)
-Called chronic papillary synovitis
-CD4+ T cells, plasma cells, macrophages, and giant cells
-these cells form lymphoid follicles
-Neutrophil invasion and fibrin in the acute phase
-Hyperplastic cells with papillary protrusion grossly that covers the articular surface.
-The defining characteristic is formation of pannus over the joint. Leading to 1. destruction of the cartilage, 2. destruction of underlying bone, and 3. ankylosis of the joint space due to fibrosis and ossification (myofibroblasts)
-it’s different from OA because it does not have prominent osteophytes ( new bone formatioN)
-Grossly its got papillary protrusions, but it also has lymphocytes
-
Rheumatoid nodules
- location (1 common; 6 uncommon)
- how common is this?
- clinical presentation
- microscopic findings
- cause of nodules?
- pressure points on BUE are most common; less common are visceral locations–lungs, spleen, pericardium, myocardium, heart valves, aorta
- It is 25% of patients with severe RA
- fibrinoid necrosis at the center of nodule with surrounding epithelioid histiocytes then plasma cells and lymphocytes
- the nodules are due to vasculitis and then necrosis caused by rheumatoid factor.
What type of necrosis is found at the center of a rheumatoid nodule? What surrounds it?
-What is this pattern called?
Fibrinoid necrosis. surrounded by epithelioid histiocytes and then lymphocytes + plasma cells
-palisaded inflammation
History features of RA
- duration of morning stiffness.
- Does the stiffness improve or worsen?
- onset speed?
- symmetrical or asymmetrical?
- physical symptoms/difficulty with what activities
- Which joints are involved?
- what are some common physical finding (4)
- morning stiffness lasting for more than 1 hour for more than 6 weeks.
- The stiffness improves with activity
- gradual onset
- symmetrical sx
- pain with activities requiring turning motion of the fingers. Also metatarsal pain with walking on hard floors.
- PIP and MCP. DIP is usually spared.
- Radial deviation of the radiocarpal joint; Ulnar deviation at the MCP joint; Swan neck deformity (due to tightness of intrinsic muscles); and Boutinere’s deformity (extensor muscles fall down to act as flexors)
RA risk factors: (6)
- Genetics: HLA-DR4 and HLA-DR1 (first degree relatives have a 1.5x chance of developing disease
- Gender: females have 2.5x more than males
- Infection
- Stress
- Smoking
- Ethnicity (Rural africans (0.1%); Chippewa and Pima Indians (5%)