Osteomyelitis is an inflammation or swelling of bone tissue that is usually the result of an infection. It may occur for many different reasons and can affect children or adults. Some of the causes of osteomyelitis include the following:
A bacterial bloodstream infection, sometimes called bacteremia, or sepsis, that spreads to the bone. This type is most common in infants and children and usually affects their long bones such as the femur (thighbone) or humerus (upper arm bone). When osteomyelitis affects adults, it often involves the vertebral bones along the spinal column. The source of the blood infection is usually Staphylococcus aureus, although it may be caused by a different type of bacteria or fungal organism.
A nearby infection due to a traumatic injury, frequent medication injections, a surgical procedure, or use of a prosthetic device. In addition, individuals with diabetes who develop foot ulcers are more susceptible. In any of these situations, the organism has a direct portal of entry into the affected bone.
Individuals with weakened immune systems are more likely to develop osteomyelitis. This includes individuals with sickle cell disease, human immunodeficiency virus (HIV), or individuals receiving immunosuppressive medications such as chemotherapy or steroids.
Osteomyelitis can have a sudden onset, a slow and mild onset, or may be a chronic problem, depending on the source of the infection.
Who is affected by osteomyelitis?
Osteomyelitis can affect all populations from infants and children to the elderly. It is more common in infants, children, and older adults. The incidence in males is greater than females. Populations at increased risk include individuals with weakened immune systems.