What is the most common route of disease causation of chronic osteomyelitis?
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Osteomyelitis (pronounced: os-tee-oh-my-uh-LY-tus) is the medical term for in a bone. It's usually caused by a bacterial infection. It often affects the long bones of the arms and legs, but can happen in any bone. Show
What Are the Signs & Symptoms of Osteomyelitis?Teens with osteomyelitis often feel pain in the infected bone. They also might:
Teens tend to get osteomyelitis after an accident or injury. The injured area may begin to hurt again after seeming to get better. What Causes Osteomyelitis?Bacteria can infect bones in a few ways. For instance:
Is Osteomyelitis Contagious?No, bones infections aren't contagious. But the germs that cause osteomyelitis can sometimes pass from one person to another. How Is Osteomyelitis Diagnosed?If you have a fever and bone pain, visit the doctor right away. Osteomyelitis can get worse within hours or days and become much harder to treat. The doctor will do a physical exam and ask questions about recent injuries to the painful area. Blood tests can check for an increased white blood cell count (a sign of infection) and other signs of possible inflammation or infection. An X-ray may be ordered although X-rays don't always show signs of infection in a bone in the early stages. The doctor might suggest a to get a more detailed look at the bone. The doctor might also recommend an MRI, which gives much more detailed images than X-rays. MRIs not only can diagnose osteomyelitis, but can help establish how long the bone has been infected. The doctor may do a to get a sample from the bone. This lets the doctor find out which bacteria caused the infection. It also can help the doctor decide which antibiotic would best treat the infection. How Is Osteomyelitis Treated?Treating osteomyelitis depends on:
Treatment includes antibiotics for the infection and medicine for pain relief. Most people with osteomyelitis spend a couple of days in the hospital to get IV (given in a vein) antibiotics to fight the infection. They can go home when they feel better, but might need to continue IV or oral antibiotics for several more weeks. Sometimes surgery is needed to clean out an infected bone. If a cavity or hole developed in the bone and is filled with pus (a collection of bacteria and white blood cells), a doctor will do a debridement. In this procedure, the doctor cleans the wound, removes dead tissue, and drains pus out of the bone so that it can heal. pHow Long Does Osteomyelitis Last?Most people with osteomyelitis feel better within a few days of starting treatment. IV antibiotics often are switched to oral form in 5 to 10 days. People usually get antibiotics for at least a month, and sometimes longer depending on symptoms and blood test results. Can Osteomyelitis Be Prevented?One way to prevent osteomyelitis is to keep skin clean. All cuts and wounds — especially deep wounds — should be cleaned well. Wash a wound with soap and water, holding it under running water for at least 5 minutes to flush it out. To keep the wound clean afterward, cover it with sterile gauze or a clean cloth. You can apply an over-the-counter antibiotic cream, but the most important thing is to keep the area clean. Wounds should begin healing within 24 hours and completely heal within a week. A wound that takes longer to heal or causes extreme pain should be checked by a doctor. And, as with many infections, wash your hands well and often to stop the spread of germs. Also be sure that your vaccinations are up to date. Osteomyelitis (OM) is an infection of bone. Symptoms may include pain in a specific bone with overlying redness, fever, and weakness. The long bones of the arms and legs are most commonly involved in children e.g. the femur and humerus, while the feet, spine, and hips are most commonly involved in adults. The cause is usually a bacterial infection, but rarely can be a fungal infection. It may occur by spread from the blood or from surrounding tissue. Risks for developing osteomyelitis include diabetes, intravenous drug use, prior removal of the spleen, and trauma to the area. Diagnosis is typically suspected based on symptoms and basic laboratory tests as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR).This is because plain radiographs are unremarkable in the first few days following acute infection. Diagnosis is further confirmed by blood tests, medical imaging, or bone biopsy. Treatment of bacterial osteomyelitis often involves both antimicrobials and surgery. In people with poor blood flow, amputation may be required. Treatment of the relatively rare fungal osteomyelitis as mycetoma infections entails the use of antifungal medications. In contrast to bacterial osteomyelitis, amputation or large bony resections is more common in neglected fungal osteomyelitis, namely mycetoma, where infections of the foot account for the majority of cases. Treatment outcomes of bacterial osteomyelitis are generally good when the condition has only been present a short time. About 2.4 per 100,000 people are affected each year. The young and old are more commonly affected. Males are more commonly affected than females. The condition was described at least as early as the 300s BC by Hippocrates. Prior to the availability of antibiotics, the risk of death was significant. Signs and symptoms[edit]Symptoms may include pain in a specific bone with overlying redness, fever, and weakness and inability to walk especially in children with acute bacterial osteomyelitis. Onset may be sudden or gradual. Enlarged lymph nodes may be present. In fungal osteomyelitis, there is usually a history of walking bare-footed, especially in rural and farming areas. Contrary to the mode of infection in bacterial osteomyelitis, which is primarily blood-borne, fungal osteomyelitis starts as a skin infection, then invades deeper tissues until it reaches bone. Age groupMost common organismsNewborns (younger than 4 mo)Staphylococcus aureus, Enterobacter species, and group A and B Streptococcus speciesChildren (aged 4 mo to 4 y)S. aureus, group A Streptococcus species, Haemophilus influenzae, and Enterobacter speciesChildren, adolescents (aged 4 y to adult)S. aureus (80%), group A Streptococcus species, H. influenzae, and Enterobacter speciesAdultS. aureus and occasionally Enterobacter or Streptococcus speciesSickle cell anemia patientsSalmonella species are most common in patients with sickle cell disease.In children, the metaphyses, the ends of long bones, are usually affected. In adults, the vertebrae and the pelvis are most commonly affected. Acute osteomyelitis almost invariably occurs in children who are otherwise healthy, because of rich blood supply to the growing bones. 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 the synovium (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 coli are 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 infections may also cause osteomyelitis. The two most common are Blastomyces dermatitidis and Coccidioides immitis.[citation needed] 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 spine was so common before the initiation of effective antitubercular therapy, it acquired a special name, Pott's disease.[citation needed] The Burkholderia cepacia complex has been implicated in vertebral osteomyelitis in intravenous drug users. Pathogenesis[edit]In general, microorganisms may infect bone through one or more of three basic methods The area usually affected when the infection is contracted through the bloodstream is the metaphysis of the bone. Once the bone is infected, leukocytes enter the infected area, and, in their attempt to engulf the infectious organisms, release enzymes that lyse the bone. Pus spreads into the bone's blood vessels, impairing their flow, and areas of devitalized infected bone, known as sequestra, form the basis of a chronic infection. Often, the body will try to create new bone around the area of necrosis. The resulting new bone is often called an involucrum. On histologic examination, these areas of necrotic bone are the basis for distinguishing between acute osteomyelitis and chronic osteomyelitis. Osteomyelitis is an infective process that encompasses all of the bone (osseous) components, including the bone marrow. When it is chronic, it can lead to bone sclerosis and deformity.[citation needed] Chronic osteomyelitis may be due to the presence of intracellular bacteria. Once intracellular, the bacteria are able to spread to adjacent bone cells. At this point, the bacteria may be resistant to certain antibiotics. These combined factors may explain the chronicity and difficult eradication of this disease, resulting in significant costs and disability, potentially leading to amputation. The presence of intracellular bacteria in chronic osteomyelitis is likely an unrecognized contributing factor in its persistence.[citation needed] In infants, the infection can spread to a joint and cause arthritis. In children, large subperiosteal abscesses can form because the periosteum is loosely attached to the surface of the bone. Because of the particulars of their blood supply, the tibia, femur, humerus, vertebrae, maxilla and the mandibular bodies are especially susceptible to osteomyelitis. Abscesses of any bone, however, may be precipitated by trauma to the affected area. Many infections are caused by Staphylococcus aureus, a member of the normal flora found on the skin and mucous membranes. In patients with sickle cell disease, the most common causative agent is Salmonella, with a relative incidence more than twice that of S. aureus. Diagnosis[edit]Mycobacterium doricum osteomyelitis and soft tissue infection. Computed tomography scan of the right lower extremity of a 21-year-old patient, showing abscess formation adjacent to nonunion of a right femur fracture. Extensive osteomyelitis of the forefoot Osteomyelitis in both feet as seen on bone scan The diagnosis of osteomyelitis is complex and relies on a combination of clinical suspicion and indirect laboratory markers such as a high white blood cell count and fever, although confirmation of clinical and laboratory suspicion with imaging is usually necessary. Radiographs and CT are the initial method of diagnosis, but are not sensitive and only moderately specific for the diagnosis. They can show the cortical destruction of advanced osteomyelitis, but can miss nascent or indolent diagnoses. Confirmation is most often by MRI. The presence of edema, diagnosed as increased signal on T2 sequences, is sensitive, but not specific, as edema can occur in reaction to adjacent cellulitis. Confirmation of bony marrow and cortical destruction by viewing the T1 sequences significantly increases specificity. The administration of intravenous gadolinium-based contrast enhances specificity further. In certain situations, such as severe Charcot arthropathy, diagnosis with MRI is still difficult. Similarly, it is limited in distinguishing avascular necrosis from osteomyelitis in sickle cell anemia. Nuclear medicine scans can be a helpful adjunct to MRI in patients who have metallic hardware that limits or prevents effective magnetic resonance. Generally a triple phase technetium 99 based scan will show increased uptake on all three phases. Gallium scans are 100% sensitive for osteomyelitis but not specific, and may be helpful in patients with metallic prostheses. Combined WBC imaging with marrow studies has 90% accuracy in diagnosing osteomyelitis. 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 cannot be trusted to produce reliable results. Factors that may commonly complicate osteomyelitis are fractures of the bone, amyloidosis, endocarditis, or sepsis. The definition of OM is broad, and encompasses a wide variety of conditions. Traditionally, the length of time the infection has been present and whether there is suppuration (pus formation) or osteosclerosis (pathological increased density of bone) are used to arbitrarily classify OM. Chronic OM is often defined as OM that has been present for more than one month. In reality, there are no distinct subtypes; instead, there is a spectrum of pathologic features that reflects a balance between the type and severity of the cause of the inflammation, the immune system and local and systemic predisposing factors.[citation needed]
OM can also be typed according to the area of the skeleton in which it is present. For example, osteomyelitis of the jaws is different in several respects from osteomyelitis present in a long bone. Vertebral osteomyelitis is another possible presentation.[citation needed] Treatment[edit]Osteomyelitis often requires prolonged antibiotic therapy for weeks or months. A PICC line or central venous catheter can be placed for long-term intravenous medication administration. Some studies of children with acute osteomyelitis report that antibiotic by mouth may be justified due to PICC-related complications. It may require surgical debridement in severe cases, or even amputation. Antibiotics by mouth and by intravenous appear similar. Due to insufficient evidence it is unclear what the best antibiotic treatment is for osteomyelitis in people with sickle cell disease as of 2019. Initial first-line antibiotic choice is determined by the patient's history and regional differences in common infective organisms. A treatment lasting 42 days is practiced in a number of facilities. Local and sustained availability of drugs have proven to be more effective in achieving prophylactic and therapeutic outcomes. Open surgery is needed for chronic osteomyelitis, whereby the involucrum is opened and the sequestrum is removed or sometimes saucerization can be done. Hyperbaric oxygen therapy has been shown to be a useful adjunct to the treatment of refractory osteomyelitis. Before the widespread availability and use of antibiotics, blow fly larvae were sometimes deliberately introduced to the wounds to feed on the infected material, effectively scouring them clean. There is tentative evidence that bioactive glass may also be useful in long bone infections. Support from randomized controlled trials, however, was not available as of 2015. Hemicorporectomy is performed in severe cases of Terminal Osteomyelitis in the Pelvis if further treatment won’t stop the infection. History[edit]The word is from Greek words ὀστέον osteon, meaning bone, μυελό- myelo- meaning marrow, and -ῖτις -itis meaning inflammation. In 1875, American artist Thomas Eakins depicted a surgical procedure for osteomyelitis at Jefferson Medical College, in an oil painting titled The Gross Clinic.[citation needed] Fossil record[edit]Evidence for osteomyelitis found in the fossil record is studied by paleopathologists, specialists in ancient disease and injury. It has been reported in fossils of the large carnivorous dinosaur Allosaurus fragilis. Osteomyelitis has been also associated with the first evidence of parasites in dinosaur bones. What is the most common site of osteomyelitis?In adults, osteomyelitis most often affects the vertebrae of the spine and/or the hips. However, extremities are frequently involved due to skin wounds, trauma and surgeries.
Which is the most common organism's causing osteomyelitis in all age groups?Staphylococcus aureus is the most common cause of acute and chronic hematogenous osteomyelitis in adults and children. [1][5] Increasingly isolated from patients with osteomyelitis is methicillin-resistant Staphylococcus aureus (MRSA). In some studies, MRSA accounted for over one-third of all staphylococcal isolates.
When does osteomyelitis become chronic?Acute osteomyelitis typically refers to an infection of less than 1 month's duration, whereas chronic osteomyelitis refers to infection that lasts longer than 4 weeks.
What is the most common cause of osteomyelitis in sickle cell disease?Although Salmonella has been cited as the principal causative organism of osteomyelitis in patients who have sickle-cell disease, in our experience Staphylococcus aureus was the most common infecting organism.
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