Osteomyelitis
Osteomyelitis is bone infection from hematogenous seeding or contiguous spread, most often from Staphylococcus aureus, presenting as subacute pain with or without a draining sinus tract and confirmed by bone biopsy culture. Empiric antibiotics are withheld until biopsy in a stable patient, and treatment combines source control with 4 to 6 weeks of culture-directed antibiotics, extended to 6 weeks or indefinite suppression for hardware-associated or chronic disease.
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What this article covers
- Overview
Osteomyelitis is infection of bone, arising from hematogenous dissemination of bacteria or from contiguous spread from an adjacent wound, surgical site, orthopedic hardware, or soft tissue infection.
- Epidemiology
Incidence among adults is increasing in the United States, driven largely by the rising prevalence of diabetes mellitus and its associated foot ulcers.
- Risk factors
Injection drug use, the strongest risk factor for hematogenous vertebral osteomyelitis.
- Pathophysiology
Hematogenous osteomyelitis begins with bacteremic seeding of a bone site, most often the vertebral disk space in adults, with spread to the adjacent end plates (spondylodiskitis); the lumbar spine is…
- Clinical features
Subacute to chronic pain over the affected bone is the hallmark presentation; fever and systemic toxicity are uncommon except with acute hematogenous seeding.
- Differential diagnosis
Septic arthritis: a hot, effused joint with markedly restricted range of motion and synovial fluid leukocytosis above 50,000/microliter on arthrocentesis excludes isolated osteomyelitis, though the two can coexist.
- Diagnosis
Osteomyelitis is confirmed by bone biopsy for culture and histopathologic examination, obtained at surgery or by image-guided biopsy; biopsy is generally unnecessary when blood cultures are already…
- Management
First, unless the patient has sepsis, bacteremia, or soft tissue infection, withhold empiric antibiotics until bone biopsy or blood culture identifies the organism, since susceptibility results should guide the antibiotic selected.
- Complications
Sepsis and bacteremia, particularly with acute hematogenous disease, are the most immediately life-threatening complications.
- Prognosis
Acute hematogenous osteomyelitis treated promptly with source control and a full antibiotic course generally has a favorable outcome, though relapse can occur, particularly with retained hardware.
- Prevention
Screen every diabetic foot ulcer for osteomyelitis when deep with exposed bone, greater than 2 cm in diameter, or nonhealing after 6 weeks of standard wound care, since these three cut-offs identify…
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