Osteomyelitis and infective endocarditis.

Osteomyelitis is thought to occur as a complication of infectious endocarditis in as many as 6% of cases of endocarditis. We describe this association in three patients. Osteomyelitis may be difficult to diagnose in patients with endocarditis because symptoms such as fever, bone pain and stiffness are common to both illnesses, therefore physicians need to have a high index of suspicion to avoid missing this important complication. We recommend that patients with endocarditis and persistent or localized musculoskeletal symptoms should be investigated to exclude osteomyelitis. Plain radiographs can be normal in 50% of cases of osteomyelitis in the early stages or show only minor abnormalities, but bone scans are highly sensitive. We suggest that a bone scan is performed if radiography is unhelpful, since a diagnosis of osteomyelitis can effectively be excluded if the bone scan is normal. We advocate close follow-up of these patients with prolonged antibiotic treatment consisting of at least 6 weeks of intravenous therapy, and 3 months or longer of oral therapy.