Review Question - QID 105977

Action	Numeric Key	Letter Key	Function Key
Choose 1	1
Choose 2	2
Choose 3	3
Choose 4	4
Choose 5	5
Submit Response			Enter
Previous Question			Left Arrow
Next Question		N	Right Arrow
Open/Close Bookmode		C
Open Image			Spacebar

Septic Arthritis QID: 105977 (M2.OR.14.8)

QID 105977 (Type "105977" in App Search)

A 61-year-old man with hypertension and rheumatoid arthritis (RA) schedules a same-day appointment with his primary care physician for worsening pain in his right wrist. He was diagnosed with RA 8 years ago and has been doing fairly well. Both of his wrists, fingers, and knees have been affected for several years, but today his pain is much worse than baseline. His medications include methotrexate, naproxen, atenolol, and lisinopril. The patient's vital signs are as follows: T 100.9 F, HR 95 bpm, BP 110/71 mmHg, and RR 16 rpm. On exam you note tender, swollen wrists bilaterally. The right wrist is slightly warm to touch and resists passive movement. There is mild ulnar deviation of the digits on both hands. The metacarpalphalangeal joints are mildly tender. Which of the following is the most appropriate course of management?

Type & Select Correct Answer

Type in at least one full word to see suggestions list

Increase methotrexate

0/6

Add acetominophen

0/6

Add a short course of corticosteroids

17%

1/6

Initiate treatment with rituximab

0/6

Perform arthrocentesis

83%

5/6

Select Answer to see Preferred Response

Review TC In New Tab

This patient has signs and symptoms concerning for a septic joint. His wrist must be aspirated and fluid sent for cell count and culture. Antibiotics should then be initiated.

In a patient with a fever and a painful, warm, and swollen joint, the diagnosis of septic arthritis must be ruled out. While patients with RA may have joint pain and swelling at baseline, they are also at an increased risk of developing septic arthritis, particularly with staphylcoccus aureus. Patients with RA may be taking immunosuppressive medications, placing them at an increased risk of developing infection. Joint fluid must be aspirated and sent to secure the diagnosis and guide antibiotic therapy.

Horowitz et al. review the approach to the management of septic arthritis. A synovial fluid white blood cell count in patients with septic arthritis is usually greater than 50,000 per mm3. Gram stain results should generally guide initial antibiotic choice. Vancomycin can be used for gram-positive cocci, ceftriaxone for gram-negative cocci, and ceftazidime for gram-negative rods.

Kaandorp et al., in a prospective study, identified several risk factors for developing septic arthritis. These included age > or = 80 years (odds ratio [OR] = 3.5, 95% confidence interval [95% CI] 1.4-8.6), diabetes mellitus (OR = 3.3, 95% CI 1.1-10.1), rheumatoid arthritis (OR = 4.0, 95% CI 1.9-8.3), hip and/or knee prosthesis (OR = 15, 95% CI 4.1-54.3), joint surgery (OR = 5.1, 95% CI 2.2-11.9), and skin infection (OR = 27.2, 95% CI 7.6-97.1).

Illustration A is a radiograph of the wrist of a patient with septic arthritis. Note the diffuse pancarpal joint-space narrowing, a finding indicative of extensive cartilage loss.

Incorrect Answers:
Answers 1-4: Escalating or changing therapy for poorly controlled RA may be accomplished with any of these options. However, this scenario is greatly concerning for septic arthritis, a diagnosis which must be ruled out before attributing this patient's pain to his RA.

ILLUSTRATIONS: