Flashcards in Week 4 - Case 2 Deck (24)
What is acute monoarticular arthritis?
An acute joint inflammation that occurs days or less before seeking attention - (mono = one joint)
What is the common differential for Acute Monoarticular Arthritis?
3. Reactive arthritis
4. Septic arthritis
What causes gout?
Uric acid crystals precipitate in the joint
Describe gout and how it is diagnosed.
Very acute onset, low grade fever, most common site is great toe, uncommon in shoulders
Diagnosis: joint aspiration, polarized light demonstrates negatively birefringent crystals
What causes pseudogout?
Calcium pyrophosphate crystal deposition
What are the symptoms of pseudogout and how do you diagnose?
Looks the same as gout - can involve the same joints (feet, knee, wrist, ankle) plus shoulder and hips
Diagnosis - joint aspiration, positive birefringent crystals
What is reactive arthritis?
Acute, symmetric arthritis following urethritis (chlamydia) or gastroenteritis
-usually happens 6 weeks after infection
-Affects joints, mostly commonly knees
What are some complications of Reactive Arthritis?
Patients may also get conjunctivitis and urethritis - Reiter's syndrome
What organisms cause septic arthritis?
1. Staph aureus - most common overall, patients usually have pre-existing joint problem or are IV drug users
2. Neisseria gonorrhoeae - most common organism under age 30
How do you know a condition is septic arthritis caused by staph. aureus or Neisseria gonorrheae?
Joint aspiration - and look at the cells under microscope
What are the two muscoskeletal syndromes caused by disseminated GC (Gonococcal arthritis)?
Arthritis-dermatitis syndrome & Localized septic arthritis
What symptoms are associated with Arthritis-dermatitis syndrome (GC Arthritis)?
Arthralgias, Skin lesions, Inflammation of tendons (these three are what the patient usually comes into the office with) - Patient doesn't usually come in with an inflamed joint.
Septic arthritis is rarely found at same time as bacteremia.
What joint is commonly affected in localized septic arthritis? What is septic arthritis usually not found with?
Knee - Septic arthritis and bacteremia are rarely found at the same time
What influences dissemination/spread of Gonococcal arthritis?
-Phenotypes of GC that are expressed during menstruation are more likely to disseminate - one week after start of period
-GC in homosexual men are less likely to disseminate
-Disseminating strains are less potent inflamm. response stimulators = less likely to cause urethral symptoms
How do you diagnose GC arthritis?
History & Physical, Lab work, Gram stain & Culture
What will the labs show for a GC infection?
WBC high (above 10,000)
Blood cultures positive
Joint aspiration shows WBC count over 100,000 (not specific though - can also be seen in gout)
What is the primary diagnostic test for GC arthritis?
Gram stain & culture of joint aspiration
What does the gram stain for GC arthritis look like?
Many, large white blood cells with cocci shown in enlarged cells
How do you treat for GC arthritis?
3rd generation cephalosporin = ceftriaxone
Azithromycin = Oral macrolide antibiotic (also used for chlamydia treatment)
Prognosis is usually very good with rapid resolution of signs and symptoms
What frequently causes septic arthritis?
How can gout be diagnosed?
White count in joint aspirate
Urethritis, conjunctivitis and monoarthritis is called. . .
What are symptoms associated with mono and GC arthritis (septic joint)?
-right knee pain
-right knee swollen & very tender