WBR0850

Author	[[PageAuthor::Mohamed Moubarak, M.D. [1]]]
Exam Type	USMLE Step 3
Main Category	Emergency Room
Sub Category	Infectious Disease
Prompt	An 11 year-old boy brought to the ED by his mother complaining of progressive severe pain, and swelling in his left foot. The mother said that she used some analgesic medications that were prescribed to him 10 days ago for fever after he injured himself during playing, but neither the pain nor the fever subsided. He is a diabetic on insulin, taking no other medications. On examination, the patient is feverish with temperature 39 C (102 F), heart rate 100/min, blood pressure 140/80 mmHg, and respiratory rate of 22/min. His left foot is severely tender, red, and hot, with decreased range of motion on examination. You ordered x-ray which turned back with no pathology. What is the best next step in managing this case?
Answer A	Order blood culture then proceed with treatment
Answer A Explanation	Correct Although the diagnosis of osteomyelitis is often based on radiologic results showing a lytic center with a ring of sclerosis, blood culture is the first to be done to direct the treatment towards the causative organism
Answer B	Start antibiotic treatment immediately
Answer B Explanation	Incorrect Antibiotic therapy should be started after blood culture withdrawal
Answer C	Start analgesics and ask the patient to come next week for follow up
Answer C Explanation	Incorrect Osteomyelitis is an acute bacterial infection and should be diagnosed and treated with the proper antibiotics
Answer D	It’s a self limiting disease and just need follow up
Answer D Explanation	Incorrect Osteomyelitis is not a self limiting disease, and can lead to severe destruction of the bone if left untreated
Answer E	Order ESR for this patient
Answer E Explanation	Incorrect ESR is a non specific test and will not help in reaching the diagnosis
Right Answer	A
Explanation	Osteomyelitis is an infection of bone or bone marrow, usually caused by pyogenic bacteria or mycobacteria. It can be usefully subclassifed on the basis of the causative organism, the route, duration and anatomic location of the infection. It usually present with fever, chills, erythema, and swelling over the involved bone. Educational Objective: References:
Approved	No
Keyword	[[WBRKeyword::Osteomyelitis]]
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