acute hematogenous osteomyelitis in children
Introduction
Introduction to acute blood-borne osteomyelitis in children Acute hematogenous osteomyelitis (acute hematogenous osteomyelitis) is also called acute osteomyelitis, because in most cases, the purulent bacteria invade the inflammation caused by connective tissue in the bone marrow. A small number of infections from adjacent soft tissue spread or secondary to open fractures, if not treated in time, will cause bone structure damage, disability, and even spread and life-threatening. Some cases can be converted into chronic lesions, and the course of disease is long. Because it is more common in children, it may affect the nutrition and growth of children. basic knowledge The proportion of illness: 0.005% Susceptible people: children Mode of infection: non-infectious Complications: brain abscess toxic shock syndrome
Cause
Causes of acute blood-borne osteomyelitis in children
Bacterial infections
The pathogen is often hemolytic Staphylococcus aureus. In recent years, it has also toxic Hemolytic Staphylococcus aureus. Occasionally, Salmonella, pneumococcal or other pyogenic bacteria are found. Most of them are resistant to blue and streptomycin. The primary lesions were pustules, gingival abscesses and upper respiratory tract infections.
Indirect factor
Clinically, local tissue damage caused by sprains and contusions is often an indirect cause of osteomyelitis.
Body factor
The part of the bone marrow cavity is supplied by the nourishing blood vessel, and the cortical part close to the periosteum is supplied by the subperiosteal small blood vessel network. When the periosteum is lifted by the abscess, the cortical bone loses the blood supply from the periosteum, which seriously affects the circulation of the bone and causes osteonecrosis. After the pus enters the bone marrow and the central canal, the nourishing blood vessels passing through the lumen form thrombus and pustules due to inflammation. The blood supply in the bone is blocked, causing osteonecrosis, and the wound is not healed for a long time, becoming chronic osteomyelitis.
After the formation of intraosseous infection, the surrounding area is bone, the drainage is not smooth, and there are many severe toxemia manifestations. Later, as the abscess expands, the infection spreads along the direction of less local resistance.
Prevention
Acute blood-borne osteomyelitis prevention in children
Mostly caused by blood-borne disseminated infection, it should be actively prevented, treated for sepsis, actively prevent various infectious diseases of the skin and mucous membranes, and actively prevent upper respiratory tract infections.
Complication
Acute blood-borne osteomyelitis complications in children Complications, brain abscess, toxic shock syndrome
Often accompanied by other areas of serious infections, such as suppurative pericarditis, pneumothorax, brain abscess, and heart, lung, liver, kidney and other organs of migratory lesions, resulting in toxic shock, multiple organ damage.
Symptom
Acute blood-borne myelopathic symptoms in children Common symptoms Hyperthermia joint swelling and painful joint effusion severe pain refusal to eat coma pericarditis brain abscess shock
The most common site of osteomyelitis is the lower end of the femur and the upper end of the humerus, followed by the upper end of the femur, the distal end of the tibia and the tibia, but other bones can occur. Symptoms and signs follow the severity of the infection, the location, the extent of inflammation, and the duration of the disease. The age of the sick child and the size of the resistance vary in clinical manifestations and can be roughly divided into three types:
1. Sepsis type: This type accounts for about 80%. The systemic symptoms are acute sepsis. It can have symptoms such as high fever, coma, convulsions, and even toxic shock. Because of bloody spread, it is often accompanied by other parts. Severe infections, such as suppurative pericarditis, purulent pneumonia, brain abscess, etc., severe cases can be accompanied by migratory lesions of the heart, lung, liver, kidney and other organs, resulting in functional damage of multiple organs, local symptoms for limb persistence Severe pain, inactivity, tenderness, axial pain, and circumferential swelling. Invasive bone lesions can be single or multi-bone. In a few cases, systemic symptoms are the main manifestations, and local signs of the bone show very late. It is necessary to detect bone lesions early.
2. Concurrent arthritis type: Most of these types are newborns and small babies. The systemic symptoms are often mild, the body temperature is not high, but there are irritations, antifeeding and weight loss. The lesions are more common in the upper end of the femur, the upper end of the humerus or the upper end of the humerus. Since the metaphyseal end is included in the joint capsule or the dry end damage affects the attachment of the tarsal plate, the inflammation easily spreads into the joint, and some stagnation or destruction occurs, which affects the future development.
3. Localized destruction or bone abscess type: This type is more common in school-age children, with mild clinical symptoms, local swelling and pain, limited joint activity in the vicinity, and sympathetic joint effusion may occur in some children.
4. There are primary infections, and the common primary lesions include pustules and gingival abscesses.
Examine
Examination of acute blood-borne osteomyelitis in children
In patients with acute suppurative osteomyelitis, white blood cells and neutrophils are significantly increased in the early stage, which may be accompanied by anemia and increased erythrocyte sedimentation rate. The positive rate of early blood bacterial culture is 50% to 75%, usually obtained 24 hours after infection. Blood positive culture results, local bone puncture to extract pus, smear to find bacteria can be diagnosed, blood and pus bacterial culture should be used as a bacterial drug sensitivity test in order to choose effective antibiotic treatment.
1. X-ray examination: X-ray examination within 14 days after onset is often found to be abnormal. The time of X-ray manifestation in cases with antibiotics can be delayed to about 1 month. X-ray examination is difficult to show bones less than 1 cm in diameter. Abscess, so the early X-ray showed a lamellar periosteal reaction and sparse osteoporosis. When a tiny bone abscess merged into a larger abscess, the scattered worm-like bone destruction occurred in the sacral area on the X-ray film. And expand to the medullary cavity, at which time the bone density becomes thinner, and the irregular changes of the inner layer and the outer layer occur in turn. The result of bone destruction is the formation of dead bone, the dead bone can be large or small, and the small dead bone is expressed as density. Increased shadow, located in the abscess, completely free from the surrounding bone tissue, the large dead bone can be the entire segment of osteonecrosis, increased density and no trabecular structure visible, a few cases have pathological fractures.
2. CT examination: subperiosteal abscess can be found in advance, but it is still difficult to show for small bone abscess.
3. MRI examination: It can be found earlier that there is an inflammatory abnormal signal in the metaphysis and diaphysis of the long bone, and it can also show subperiosteal abscess. Therefore, MRI is superior to X-ray and CT examination.
4. Radionuclide bone imaging: vasodilatation and increase of the lesion site, so that 99mTc is concentrated in the early stage of the lesion at the metaphysis, generally there is a positive result 48 hours after the onset, radionuclide bone imaging can only show The location of the lesion, but can not make a qualitative diagnosis, so this test only has the value of indirect help diagnosis.
Diagnosis
Diagnosis and diagnosis of acute hematogenous osteomyelitis in children
diagnosis
Two problems should be solved in the diagnosis, namely disease diagnosis and cause diagnosis. The diagnosis should be early. Because the X-ray appearance is very late, the X-ray examination results cannot be used as a diagnosis basis. For those who have the condition, MRI examination can be obtained. The diagnosis of acute osteomyelitis is a comprehensive diagnosis. Anyone with the following manifestations should have the possibility of acute osteomyelitis:
1. Rapid hyperthermia and toxemia performance.
2. The long bones are painful and do not want to move the limbs.
3. There is an obvious tenderness area there.
4. Increased white blood cell count and neutrophil ratio. Local stratified puncture has diagnostic value.
The cause of the diagnosis is the acquisition of pathogenic bacteria. Blood culture and layered puncture fluid culture have great value. In order to increase the positive rate, blood culture is repeated.
A definitive diagnosis and appropriate treatment should be made early in the onset of illness to avoid the development of chronic osteomyelitis. According to reports in the literature, diagnosis and reasonable treatment within 5 days after onset can reduce the chance of acute blood-borne osteomyelitis transition to a chronic phase.
Differential diagnosis
1. Soft tissue cellulitis or deep abscess: swelling is limited to one side of the limb, no axial pain.
2. Limb pain caused by scurvy, pseudospasm and subperiosteal hematoma: There is a history of vitamin C deficiency and special scurvy disease of X-ray metaphysis, and the symptoms are quickly relieved after vitamin C.
3. Infant cortical hyperplasia: mainly found in small infants under 6 months, the systemic symptoms are light, may have low fever, irritability, local swelling, limbs can be pseudo-sputum, X-ray film is characterized by a large number of new bone under the periosteum, If it is a long bone disease, the lesion is limited to the backbone, and it never affects the metaphysis and the epiphysis.
4. Acute leukemia: local swelling and tenderness in patients with localized bone destruction, such as accompanied by fever and erythrocyte sedimentation rate and normal white blood cell count, often misdiagnosed as osteomyelitis, but pay attention to the history, visible decalcification on X-ray films And the new affected lesions appear, suggesting a systemic disease, bone marrow puncture can be diagnosed.
