Osteomyelitis

Osteomyelitis is an acute or chronic process of bone and its structures, secondary infection microorgamisne piogene. Infection associated with osteomyelitis may be localized or may extend through the periosteum, cortex, bone marrow and other adjacent tissues. Finctie bacterial pathogen varies by patient age and mechanism of infection.
There are two main categories of osteomyelitis: inoculatie marrow and direct or contiguous. Marrow Osteomyelitis is an infection caused by bacterial seeding via the bloodstream. Acute osteomyelitis marrow is characterized by acute infection of the bone caused by bacterial seeding from another source through the blood. Occurs mostly in children. Frequency location is rapidly growing bones metaphysics.Through direct or contiguous inoculation osteomyelitis is caused by direct contact with tissue and bacteria during trauma or surgery.This is a secondary bone infection inoculation of organisms by direct trauma or sepsis out of a surgery. Clinical manifestations of this type are more localized than those of osteomyelitis tends to involve the marrow and several organs.Other catogorii chronic form of osteomyelitis include the secondary and peripheral vascular disease. Chronic osteomyelitis persists or recurs, according to the original cause and mechanisms. Although listed as the etiology, peripheral vascular disease is a predisposing factor today than a cause of infection.
Morbidity can be significant and include the extension of the infection localized to adjacent tissues or joints, as progression to chronic pain and disability, amputation of the affected extremity, generalized infection or sepsis. Up to 10-15% of patients with vertebral osteomyelitis will develop neurologic sequelae or spinal cord compression. Up to 30% of pediatric patients with osteomyelitis of long bones will develop deep vein thrombosis. The mortality rate is low, unless associated sepsis or other pathological condition of the fund.
Antibiotic treatment is initiated promptly, preferably after they got sucked blood and bone samples for bacterial culture. Many antimicrobial agents are selected to cover common pathogens.Treatment of osteomyelitis is represented by parenteral antibiotics to penetrate the joints and bones. Treatment is indicated at least 4-6 weeks. After intravenous antibiotic therapy can be continued orally Depending on the type and location of infection.Marrow acute osteomyelitis can be prevented by avoiding bacterial insamintarii bone with adequate diagnosis and treatment of primary infection. By direct inoculation osteomyelitis can be prevented by proper cleaning of the wound and antibiotic prophylaxis.
Pathogenesis of osteomyelitisAcute OsteomyelitisDepending on the route of infection, acute osteomyelitis can be divided into marrow and exogenous (direct). Osteomyelitis marrow is seen predominantly in children and vascular involve long bones, especially those of the lower limb. In adults, marrow expansion is more common in lumbar vertebral corpus.
Before puberty begins veins sinus infection metaphyses. Because the bones are rigid structures, focal edema accumulates under pressure and lead to local tissue necrosis, trabecular bone breakage and removal of bone matrix and calcium. The infection spreads along the haversian bone, and marrow cavity in the bone periosteum. Ischemic vascular destruction secondary cause of death osteocitelor and seizure training. Periostial new bone formation above the attachment is known as involucrum.In acute osteomyelitis infectious process shows five stages:-Inflammation: initial inflammation with vascular congestion and increased intraosseous pressure, obstruction of blood flow and intravascular thrombosis-Suppurativa: pus in the bone through the haversian forces and form an abscess in three days subperiostial-Sequestration: high pressure, vascular obstruction and infectious trombusii compromise periosteal blood supply of bone necrosis and forcing endostial and seizure training in 7 days-Involucrum: new bone formation on the surface of the periosteum-Resolution or progression to complications: Early antibiotic treatment and osteomyelitis in the disease resolves without complications.
Chronic OsteomyelitisIt is a severe infection, persistent and incapacitating bone and bone marrow. It is often a recurrent condition difficult to treat because it is definitive.The disease can result from:Inadequate treatment of acute osteomyelitis,-Type of osteomyelitis hematogen-Trauma-Iatrogenic causes such as arthroplasty and internal fixation of fractures-Burst fractures-Infections with organisms such as Mycobacterium tuberculosis and Treponema species-Contiguous extension of soft tissues in ulcers associated with diabetes or peripheral vascular disease.
Specific forms of chronic osteomyelitis:Brodie abscess:It is a form of chronic osteomyelitis that occurs in the absence of a previous episode of acute osteomyelitis. Localized abscesses to bone lesions due almost metaphysical.Tuberculous Osteomyelitis:Expansion of secondary infection is a primary source of the lungs or digestive. Occurs more frequently in long bones and vertebrae.Once established, the bacilli cause chronic inflammatory reaction.Caseous necrosis appear smaller merging to form a large abscess. The infection spreads along the joint epiphyses.Syphilitic osteomyelitis:Extending through the placenta from mother to fetus spirochetelor cause congenital syphilis. Long bones are mainly affected.Congenital syphilis has two forms: periosteita and metaphysics. In periosteita, periostiumul is lifted off the shaft of long bones with new bone formation. In metaphysics is metaphysics involved juxtaepifizeala with increasing bone resorption. Absence of osteoblastic activity determine the separation of epiphysis of metaphysics.
Causes and risk factors for osteomyelitisNo agent can not be identified in over 35-40% of cases of osteomyelitis.Bacterial causes of osteomyelitis include:
Acute osteomyelitis marrow:New-born: S. aureus, Enterobacter species, Streptococcus group A and B-Children up to 4 years: S. aureus, group A Streptococcus species, Hemophilus influenzae, Enterobacter species-Children, teens: S. aureus, Streptococcus species, Hemophilus influenzae, Enterobacter species-Adults: S. aureus, Enterobacter, and Streptococcus species.
Osteomyelitis direct:-In general: S. aureus, Enterobacter and Pseudomonas speciesPuncture wound, S. aureus and Pseudomonas speciesPatients with sickle cell disease, S. aureus and Salmonella species.
Risk factors for osteomyelitis marrow:-Insertion of vascular catheters, intravenous drug abuse-Dialysis immunosuppressed status, introduction of urinary catheter-Old age, debilitating status, recent history of urinary tract infection or pneumonia, skin infections.