Osteomyelitis

From ArticleWorld

Osteomyelitis is an infection involving any aspect of bone. Usually the infection is bacterial or mycobacterial in nature. It can result from a number of pre-existing conditions and is serious enough to require prolonged treatment, often lasting for months, or surgical loss of the affected bone.

Causes

Osteomyelitis can settle in the bone by means of several underlying conditions. Tissue infections like cellulitis, if localized near bone, can invade the nearby bone and become a bony infection as well. Anytime an individual has surgery to bone, particularly those that involve artificial joints or other appliances/fixtures, bacteria can be introduced at the time of surgery or later, via blood dissemination, and infect the surgical areas.

Blood-borne osteomyelitis occurs when microorganisms in the blood settle in the bone and begin an infection. Because the femur, the tibia, the humerus and the vertebral bodies have tenuous circulatory status, they are more likely to develop this kind of infection.

Types

Acute osteomyelitis is relatively sudden in onset and the process of bone destruction has not yet had the chance to occur. Chronic osteomyelitis is an infection that has gone on for a period of time so that areas of bone are necrotic (dead). X-ray evaluation can sometimes evaluate whether or not the infection is acute or chronic.

Osteomyelitis can also be described by the bacterial organism involved. Infections from E. coli, Staphylococcus and Streptococcus are commonly spread by blood. Staphylococcus aureus is the most common locally-seeded microorganism causing osteomyelitis. In cases of vertebral body osteomyelitis, 50% are due to S. aureus and 50% are due to the bodily spread of tuberculosis.

Treatment

Osteomyelitis can be very difficult to treat. Often intravenous antibiotics are necessary, at least at the outset of treatment, followed by oral antibiotics for up to six months. If the infection is caused by tuberculosis, antitubercular therapy can be used for an extended period of time, possibly as long as a year. In resistant cases, an individual can lose a portion of the affected bone or, if severe, must undergo an amputation.