Septic Arthritis

Question 1

Presentation of septic arthritis?

Answer 1

Hot, red, painful joint and fever

Question 2

What is the first step in the management of a joint with suspected infection?

Answer 2

Arthrocentesis

A joint aspirate can be negative for organisms, and this does not rule out septic arthritis.

Question 3

What is the most common pathogen associated with septic arthritis?

Answer 3

Staph aureus

This is the most common pathogen overall.

Question 4

In patients with sickle cell disease, which pathogen should be considered?

Answer 4

Salmonella

However, if a gram-positive cocci is cultured, the answer is Staph aureus. Salmonella is a
gram-negative rod.

Question 5

What is the typical presentation of Gonococcus in sexually active patients according to the USMLE?

Answer 5

1) Monoarthritis of the knee in sexually active young patient
2) Triad: mono- or polyarthritis, cutaneous papules, tenosynovitis (inflammation of tendon sheaths)

Tenosynovitis refers to the inflammation of tendon sheaths.

Question 6

What is the treatment for septic arthritis?

Answer 6

Surgical drainage of the joint + antibiotics

The specific antibiotics are not a focus of the USMLE.

Question 7

True or False: A negative joint aspirate for organisms rules out septic arthritis.

Answer 7

False

It is essential not to rule out septic arthritis based solely on a negative aspirate.

Question 8

Fill in the blank: The presence of _______ in a sexually active young patient may indicate Gonococcus infection.

Answer 8

monoarthritis of the knee

This is a key presentation to recognize in exam scenarios.

Question 9

Epi septic arthritis

Answer 9

• Shows up as young healthy patient with recent trauma (e.g., car accident) or high-
  intensity exercise causing microtrauma (e.g., kickboxing/soccer tournament, long
  hike), as well as in sickle cell disease.
• Also occurs in patients with Hx of RA/JRA, OA, and prosthetic joints.