Question 1

A patient has marked swelling of a shoulder joint with erythema and severe pain. The provider suspects a bacterial cause. Which culture will be most helpful to determine the cause of these symptoms?&#10;A) Blood culture&#10;B) Synovial fluid culture&#10;C) Urethral culture&#10;D) Urine culture

Accepted Answer

Synovial fluid culture is the best option in this scenario because it will directly identify the bacteria causing the infection in the affected joint. Blood culture could also be helpful, but it may not always detect the bacteria in cases of localized joint infections. Urethral and urine cultures would not be helpful in identifying the cause of symptoms in a shoulder joint.

Question 2

An adolescent patient reports intermitted pain and swelling in various joints on the right side including the knee, elbow, wrist, and ankle. A physical examination reveals tenosynovitis and a maculopapular rash. Which diagnostic tests will be most helpful in determining a diagnosis in this patient?

A) Blood cultures and a complete blood count
B) Cultures of the urethra, pharynx, cervix, and rectum
C) Skin lesion scrapings and cultures
D) Urine cultures and renal function studies

B

Accepted Answer

The symptoms described, including intermittent pain and swelling in various joints, tenosynovitis, and a maculopapular rash, suggest a diagnosis of disseminated gonococcal infection (DGI). Cultures of the urethra, pharynx, cervix, and rectum are most helpful in diagnosing DGI, as Neisseria gonorrhoeae is the causative agent and these sites are common locations for gonococcal infection.

Question 3

A patient reports the sudden onset of pain, redness, and swelling in one knee joint but denies a fever. The provider elicits exquisite pain with manipulation of the joint and notes no decrease in pain when the joint is at rest. Which is the likely cause of this arthritis?

A) Bacterial infection
B) Gout
C) Lyme disease
D) Rheumatoid arthritis

A

Accepted Answer

The sudden onset of pain, redness, and swelling in one knee joint with exquisite pain with manipulation and no decrease in pain at rest suggests a bacterial infection, such as septic arthritis. Gout typically presents as recurrent attacks of joint pain and swelling, often involving the big toe, and is usually accompanied by fever. Lyme disease may result in joint pain and swelling, but is typically accompanied by other symptoms such as fever, rash, and flu-like symptoms. Rheumatoid arthritis usually involves multiple joints and is characterized by prolonged morning stiffness and symmetric joint involvement.

Deck 159: Septic Arthritis