56. Acute osteomyelitis

Osteomyelitis is an infection involving bone, caused by bacteria in most cases. It may be severe, and it may affect any bone. The pathogen may enter the bone directly (non-hematogenous osteomyelitis), usually after trauma or wounds, or from the blood (haematogenous osteomyelitis).

Acute osteomyelitis develops within days or weeks. It's most common in children < 5 years, where haematogenous spreading of S. aureus is the most common cause. It also occurs in adults, where direct spread from a trauma, ulcer, or from haematogenous spreading after IV drug use is the most common cause.

Clinical features

Symptoms include bone pain and fever.

Diagnosis and evaluation

Acute phase reactants are usually elevated and leukocytosis is usually present. Blood culture must be obtained. Bone biopsy and subsequent bone culture is the gold standard for diagnosis but is not always necessary, if the diagnosis can be made with reasonable certainty without it.

Imaging

Conventional radiography may not visualise pathology in the first 2 weeks of the disease. If the symptoms have lasted <2 weeks, CT or MRI is indicated. If it has lasted more than 2 weeks, radiography is sufficient and will show osteolysis, periosteal reaction, and bone destruction.

Management

Management is usually conservative, with broad-spectrum IV antibiotics. In refractory cases or cases where there is an abscess, surgery may be necessary.