Septic Arthritis

Question 1

• Consider septic arthritis in any ?

Answer 1

in any acutely inflamed joint, as it can destroy a joint in under 24 hours.

Question 2

which joint is affected in >50% of cases?

Answer 2

knee

Question 3

most common causative bacteria?

most common causative bacteria in prosthetics?

most common causative bacteria in DM/IVDU?

in young adults - what should be considered ?

Answer 3

staph aureus

staph epidermis

Gram -ve bacilli

Neisseria gonorrhoea

Question 4

Presentation ?

Answer 4

• Acute hot, red, swollen joint associated with an effusion.
• Fever
• Inability to move the joint at all.

Question 5

Risk Factors

Answer 5

RA
DM
Prosthetic joints
IVDU

Question 6

usually one joint: list joints in order of how commonly affected?

Answer 6

knee
hip 
shoulder 
wrist 
elbow

Question 7

Investigations

what will you see on Xray and CRP?

Answer 7

• Urgent joint aspiration (arthrocentesis) for synovial fluid microscopy and culture is key investigation.

both may be normal

Question 8

Tx:

• what Abx?
• if penicillin allergic?
• if MRSA +ve or Hx of MRSA?
• how long are Abx given for?

Answer 8

Antibiotic treatment:

Consider flucloxacillin
(clindamycin if penicillin allergy),

or if MRSA/history of MRSA try vancomycin

6-12 weeks

Question 9

A 45-year-old man presents with a painful swelling on the posterior aspect of his elbow. There is no history of trauma. On examination an erythematous tender swelling is noted. What is the most likely diagnosis?

synovial cyst
gout
septic arthritis
olecranon bursitis

Answer 9

olecranon bursitis

Swelling over the posterior aspect of the elbow. There may be associated pain, warmth and erythema. It typically affects middle-aged male patients