Arthritis Flashcards
What are the causes of Acute Monoarthritis
- Infection - Septic arthritis until proven otherwise.
- Crystal induced (Gout, Calcium Pyrophosphate),
- Reactive (could be multiple joints),
- Haemarthrosis,
- Trauma.
What are the risk factors for septic arthritis?
- Previous Arthritis,
- Trauma,
- Diabetes Mellitus,
- Immunosupression,
- Bacteremia,
- Sickle Cell anamia,
- Prosthetic joint
What is the pathogenesis of septic arthritis?
- Bacteria enter the joint and deposit in synovial lining either from haematogenous spread or local invasion/inoculation.
Synovium acts as a good growth medium for bacteria
Describe features of polyarticular septic arthritis
- Average of 4 joints, commonly knee, elbow, shoulder and hip predominate.
- Can often present without fever.
- Most commonly caused by strep/staph.
- Poor prognosis
Describe features of synovial fluid in a septic arthritis
- Over 50k white cells per mm cubed.
- Low glucose.
- Gram staining is relatively insensitive,
- Culture will be positive,
- Always use wide bore needle as pus is viscous.
What are the likely bugs to cause infection in healthy adults vs immunocompromised adults
Healthy - S. aureus, streptococcal or Neisseria gonorrhoea.
Immunocompromised - Gram negative bacteria, mycobacteria or fungi
Explain the management of septic arthritis?
- Joint aspiration, Abx therapy based on culture and surgical intervention is not responding after 48 hours of treatment
What is gout and the symptoms?
Gout is the deposition of monosodium urate/uric acid crystals in and around joints.
Symptoms include: Excruciating, burning pain in affected joint, commonly affects the 1st metatarsophalangeal joint. Swelling, redness and warmth in affected join. Asymmetrical distribution and mild fever/tachycardia with acute attacks
What are the modifiable and non-modifiable risk factors for gout?
Non modifiable: Age, male sex, race, genetic factors, impaired renal function.
Modifiable: Obesity, alcohol consumption, high purine diet, high fructose corn syrup and certain mediations (aspirin, diuretics, cyclosporin, pyrazinamide and ethambutol and nicotinic acid)
Explain the diagnosis of gout?
- Clinically via typical presentation of podagra and history of gout flares/hyperuricaemia.
- Raised serum urate between attacks,
- Synovial fluid aspiration examined under polarised light to look for gout crystals
What are the differentials for gout?
- Septic arthritis,
- Psudogout which most commonly affects the knee, wrist and shoulder
What are the goals of treatment for gout?
- In acute attacks the aim is to relieve pain and reduce inflammation via coldpacks and NSAIDs, colchicine or corticosteroids.
- Long term is prevention of attacks, prevent joint damage and eliminate tophi (deposit of uric acid). Use a urate lowering therapy such as allopurinol
What are the lifestyle modifications for gout?
- Dietary: Reduce purine intake (avoid seafood and meat high in protein), reduce fructose containing drinks and increase skimmed milk, vegetable protein.
- Weight loss,
- Moderate exercise,
- Reduce alcohol (Especially beer)
What is reactive arthritis?
- It is one of the spondyloarthropathies. It has a strong associated with HLA-B27. It occurs after an infection occurs somewhere else in the body, no organisms are in the joint. It is an immune reaction, thought to be cross reactivity between bacterial antigens and joint tissue
What is SARA?
A subgroup of reactive arthritis related to a sexually acquired infection. Most commonly chlamydia trachomatis
