Osteomyelitis is a bone infection, usually caused by bacteria, that can be either acute or chronic. This disorder usually occurs as a result of an infection in one part of the body that is transported through the bloodstream to a bone in a distant location. Among children and teens, the long bones of the legs and arms are most frequently affected. In adults, osteomyelitis most often affects the vertebrae of the spine and/or the hips.

Osteomyelitis is an infection of the bone, a rare but serious condition. Bones can become infected in a number of ways: Infection in one part of the body may spread into the bone, or an open fracture that exposes bone to may get infected.

In children, the long bones are usually affected. In adults, the vertebrae and the pelvis are most commonly affected.

Acute osteomyelitis almost invariably occurs in children. When adults are affected, it may be because of compromised host resistance due to debilitation, intravenous drug abuse, infectious root-canaled teeth, or other disease or drugs (e.g., immunosuppressive therapy).

Osteomyelitis is a secondary complication in 1-3% of patients with pulmonary tuberculosis. In this case, the bacteria, in general, spread to the bone through the circulatory system, first infecting thesynovium (due to its higher oxygen concentration) before spreading to the adjacent bone. In tubercular osteomyelitis, the long bones and vertebrae are the ones that tend to be affected.

Staphylococcus aureus is the organism most commonly isolated from all forms of osteomyelitis.

Bloodstream-sourced osteomyelitis is seen most frequently in children, and nearly 90% of cases are caused by Staphylococcus aureus. In infants, S. aureus, Group B streptococci (most common) and Escherichia coliare commonly isolated; in children from one to 16 years of age, S. aureus, Streptococcus pyogenes, and Haemophilus influenzae are common. In some subpopulations, including intravenous drug users and splenectomized patients, Gram-negative bacteria, including enteric bacteria, are significant pathogens.

The most common form of the disease in adults is caused by injury exposing the bone to local infection. Staphylococcus aureus is the most common organism seen in osteomyelitis, seeded from areas of contiguous infection. But anaerobes and Gram-negative organisms, including Pseudomonas aeruginosa, E. coli, and Serratia marcescens, are also common. Mixed infections are the rule rather than the exception.

Systemic mycotic (fungal) infections may also cause osteomyelitis. The two most common are Blastomyces dermatitidis and Coccidioides immitis.

In osteomyelitis involving the vertebral bodies, about half the cases are due to S. aureus, and the other half are due to tuberculosis (spread hematogenously from the lungs). Tubercular osteomyelitis of the spinewas so common before the initiation of effective antitubercular therapy, it acquired a special name, Pott's disease.

Following laboratory analysis of clinical data and studied literature, we can say that the bone pathological changes are induced by several interrelated mechanisms the drug components, produced clandestinely. The Burkholderia cepacia complex has been implicated in vertebral osteomyelitis in intravenous drug users.

Only two out of every 10,000 people get osteomyelitis. The condition affects children and adults, although in different ways. Certain conditions and behaviors that weaken the immune system increase a person's risk for osteomyelitis, including:

●Diabetes (most cases of osteomyelitis stem from diabetes)

●Sickle cell disease

●HIV or AIDS

●Rheumatoid arthritis

●Intravenous drug use

●Alcoholism

●Long-term use of steroids

●Bone surgery, including hip and knee replacements, also increase the chance for infection to invade a bone.

●Osteomyelitis in Children and Adults In children, osteomyelitis is usually acute. Acute osteomyelitis comes on quickly, is easier to treat, and overall turns out better than chronic osteomyelitis. In children, osteomyelitis usually shows up in arm or leg bones. In adults, osteomyelitis can be either acute or chronic. People with diabetes, HIV, or peripheral vascular disease are more prone to chronic osteomyelitis, which persists or recurs, despite treatment. Whether chronic or acute, osteomyelitis often affects an adult's pelvis or vertebrae of the spine. It can also occur in the feet, especially in a person with diabetes.

Acute osteomyelitis develops rapidly over a period of seven to 10 days. The symptoms for acute and chronic osteomyelitis are very similar and include:

●Fever, irritability, fatigue

●Nausea

●Tenderness and swelling around the affected bone

●Lost range of motion

●Osteomyelitis in the vertebrae makes itself known through severe back pain, especially at night.

Diagnosis of osteomyelitis is often based on radiologic results showing a lytic center with a ring of sclerosis. Culture of material taken from a bone biopsy is needed to identify the specific pathogen; alternative sampling methods such as needle puncture or surface swabs are easier to perform, but do not produce reliable results.

Factors that may commonly complicate osteomyelitis are fractures of the bone, amyloidosis, endocarditis, or sepsis.

Figuring out if a person has osteomyelitis is the first step in treatment. It's also surprisingly difficult. Doctors rely on X-rays, blood tests, and bone scans to get a picture of what's going on. They also need to determine the type of organism, typically bacteria, causing the infection so they can prescribe the right medication.

Treatment focuses on stopping infection in its tracks and preserving as much function as possible. Most people with osteomyelitis are treated with antibiotics, surgery, or both.

Antibiotics help bring the infection under control and often make it possible to avoid surgery. People with osteomyelitis usually get antibiotics for several weeks through an IV, and then switch to a pill form.

More serious or chronic osteomyelitis requires surgery to remove the infected tissue and bone. Osteomyelitis surgery prevents the infection from spreading further or getting so bad that amputation is the only remaining option.

The best way to prevent osteomyelitis is to keep things clean. If you or your child has a cut, especially a deep cut, wash it completely. Flush out any open wound under running water for five minutes, then bandage it in sterile bandages.

If you have chronic osteomyelitis, make sure your doctor knows about your medical history so you can work together to keep the condition under control. If you have diabetes, pay close attention to your feet and contact your doctor at the first sign of infection.

The sooner you treat osteomyelitis, the better. In cases of acute osteomyelitis, early treatment prevents the condition from becoming a chronic problem that requires ongoing treatment. Besides the pain and inconvenience of repeated infections, getting osteomyelitis under control early provides the best chance for recovery.

alcoholism ['ælkəhɔlizəm] n.酗酒

amputation [,æmpju'teiʃən] n.截肢

anaerobe [æ'nɛərəub] n.厌氧菌

bacteria [bæk'tiəriə] n.［复数］细菌

debilitation [di,bili'teiʃən] n.衰弱

diabetes [,daiə'biːtiːz] n.糖尿病

fungal ['fʌŋgəl] adj.真菌的

hematogenous [,hemə'tɔdʒinəs] adj.血源性

irritability [,iritə'biləti] n.应激性

mycotic [mai'kɔtik] adj.霉菌的

organism ['ɔːgənizəm] n.微生物

osteomyelitis ['ɔstiəu,maiə'laitis] n.骨髓炎

pathogen ['pæθədʒən] n.病原体

sclerosis [skliə'rəusis] n.硬化症

splenectomize [spli'nektəmaiz] vt.切除脾

sterile ['sterail] adj.无菌的

steroid ['sterɔid] n.类固醇

synovium [si'nəuviəm; sai-] n.滑膜

vertebrae ['vəːtibriː] n.椎骨

antitubercular therapy 抗结核的治疗

back pain 背痛

blastomyces dermatitidis 皮炎芽生菌

blood test 验血

bloodstream-sourced osteomyelitis 血源性骨髓炎

burkholderia cepacia complex, Bcc 洋葱伯克氏菌群

circulatory system 循环系统

coccidioides immitis 粗球孢子菌

E. Coli 大肠杆菌

enteric bacteria 肠道细菌

escherichia coli 大肠杆菌，大肠埃希菌

gram-negative bacteria 革兰氏阴性菌

group B streptococci 乙（B）型链球菌

haemophilus influenzae 流感嗜血杆菌

hip and knee replacements 髋关节和膝关节置换

immune system 免疫系统

immunosuppressive therapy 免疫抑制疗法

intravenous drug abuse 静脉注射吸毒

intravenous drug users 静脉注射吸毒者

needle puncture 穿刺

peripheral vascular disease 周围性血管疾病

pott's disease 脊椎结核病

pseudomonas aeruginosa 铜绿假单胞菌

pulmonary tuberculosis 肺结核

rheumatoid arthritis 类风湿关节炎

serratia marcescens 黏质沙雷菌

sickle cell disease 镰状细胞病

staphylococcus aureus (S. Aureus) 金黄色葡萄球菌

streptococcus pyogenes 化脓性链球菌

surface swabs 表面拭子

tubercular osteomyelitis 结核性骨髓炎