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Bone and joint infections. I man Abu selmia . S amar Shaheen . Bone infections. I man Abu selmia . overview. Normally, bone and joint are sterile . Infection >>Rare. Significant >> disability ,death . Osteomyelitis. Osteomyelitis is infection in the bone. Infants,children,and adults.
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Bone and joint infections Iman Abu selmia Samar Shaheen
Bone infections Iman Abu selmia
overview • Normally, bone and joint are sterile. • Infection >>Rare. • Significant >> disability ,death .
Osteomyelitis • Osteomyelitis is infection in the bone. • Infants,children,and adults. • In children >>at the ends of the long bones of the arms and legs, affecting the hips, knees, shoulders, and wrists. • In adults >>bones of the spine (vertebrae) or in the pelvis.
Risk factors • Diabetes • Hemodialysis • Injected drug use • Poor blood supply • Recent trauma • Surgery • The elderly
Symptoms • Bone pain • Fever • malaise • Local swelling, redness, and warmth Other symptoms may occur : • Chills • Excessive sweating • Low back pain • Swelling of the ankles, feet, and legs
Classification • Bacterial: • Acute osteomyelitis (subacute) • hematogenous • non- hematogenous • Chronic osteomyelitis • Nonspecific • specific (TB, syphilitic)
Non- Bacterial • Viral osteomyelitis • Fungi • Radiation osteomyelitis
Acute hematogenous osteomyelitis • mostly children • history of trauma • Long bone >> most common • In children >> metaphysis • Most vascular part • Blood flow slow • Most part subject to trauma • In adult >> epiphysis
The organisms • Gram +ve • Staphylococus aureus (80-90%) • Strep. pyogen • Strep. pneumonie • Gram -ve • Haemophilus influnzae (50% < 4 y) • E .coli • Pseudomonas auroginosa, • Proteus mirabilis
Source Of Infection • Infected umbilical cord in infants • Infection ( respiratory, intestinal, urinary, oral, boils, tonsilitis, skin abrasions)>> bacteramia • Traumatic implantation
Pathology • Minor trauma to adjacent joint , suppuration • starts at metaphysis • Subperiosteal abscess • Bone necrosis • new bone formation“ ivolucrum” • Channels through soft tissue “sinuses” • Sinuses appear thick-walled holes “cloacae” • Death of bony segment “sequestrum”
Complication • Pathological fracture. • Direct spread of infection arthritis,myositis • Blood spread septicaemia, pyaemia • Chronic suppurrative osteomyelitis .
Acute non- hematogenous osteomyelitis • Causes • Infection of fracturedbone • Infection of skull bone by direct spread • Pathologhy • Resemble hematogenous except no Subperiosteal abscess
Subacute Osteomyelitis • Brodie's abscess, a chronic abscess of bone surrounded by dense fibrous tissue and sclerotic bone. • The lesion usually is within the metaphysis, but can occur anywhere.
Chronic OM • May following acute OM. • Sclerosing osteomyelytitis of Garre • a chronic form involving the long bones, especially the tibia and femur, marked by a diffuse inflammatory reaction, increased density and spindle-shaped sclerotic thickening of the cortex, and an absence of suppuration. • Develop in the jaw and characterized by extensive new bone formation.
Complication • Secondary amyloidosis • Squamous cell carcinoma
According to the pathogenesis • Haematogenous osteomyelitis . • Contagious spread osteomyelitis. • Peripheral vascular disease. • Prostheses osteomyelitis .
Contagious spread osteomyelitis • Direct spread of bacteria from infection in adjacent tissues . • Long bone (most common) • Cranial vault >> head injury. • Sacrum >> decubitus ulceration. • Sternum >> cardiothoracic surgery. • Gram –ve bacilli. • Anaerobic bacteria.
Peripheral vascular disease. • Often affects the toes. • Streptcocci and anaerobic bacteria. • Particularly common in diabetics.
Prostheses osteomyelitis • Infections following artificial joint replacement. • Caused by • Perioperative contamination. • Haematogenous spread occurs in the posoperative period. • The causal organisms >> bacteria • Coagulase-negative staphylcocci • Streptococci • corynebacteria
Major pathogen • Neonates : • E. coli or Bacteroides spp. • Infants • Haemophilus influenzae (< of 4 years ) • Later • S.aureus • Streptococcus pyogenes • Streptococcus pneumoniae.
Special pathogen • Salmonella- immunocomromised,sickle cell disease. • Pasteurella multocida • M.tuberculosis • Fungi- IV drugs abusers or immunosuppression
Diagnosis • History and clinical examination • Blood cultures • Bone biopsy (which is then cultured) • Bone scan • Bone x-ray • MRI of the bone • Needle aspiration of the area around affected bones
Treatment • supportive treatment for pain • antibiotics • surgery
Joint infections Samar Shaheen
Septic arthritis • An acute inflammation of a joint caused by infection. • Can be: • Suppurative • Nonsuppurative • Monoarticular • Polyarticular • Commonly involves a single large joint such as the knee or hip.
High risk groups • Elderly • Diabetes mellitus • Rheumatoid arthritis • Prosthetic joint • Recent joint surgery • Skin infection • IV drug abusers
Route of infection • Blood borne infection (the most common route) • Direct inoculation • entry via penetrating injury • entry via iatrogenic means • Contiguous spread from osteomyelitis or soft tissue abscess. • In adults, the arteriolar anastomosis between the epiphysis and the synovium permits the spread of osteomyelitis into the joint space.
Clinical presentation • fever • swelling • warmth • inability to move the limb with the infected joint • severe pain in the affected joint, especially with movement
Suppurative septic arthritis • Caused by bacteria • Virtually every bacterial organism has been reported to causeseptic arthritis. • Bacterial species causing septic arthritis vary with the age of the patient. • The most common species overall is S. aureus • Neisseria gonorrhea is the most common cause in sexually active adults • H. infleunzaoccasionally implicated in preschool children.
Suppurative septic arthritis • The major consequence of bacterial invasion is damage to articular cartilage. • Organism's pathological properties, such as the chondrocyte proteases of S aureus. • Host's PMNL response. • cytokines and other inflammatory products hydrolysis of essential collagen and proteoglycans.
Gram positive S. aureus • The most common cause of septic arthritis: • adults • children older than 2 years. • 80% of infected joints affected by rheumatoid arthritis • early prosthetic joint infections (PJI) • Polyarticular arthritis • Mortality rate approaches 50%.
Gram positive CNS staphylococci • delayed PJI infections Streptococcal species • the second most common cause • Streptococcus viridans • Streptococcus pneumoniae • group B streptococci
Gonococcal arthritis N .gonorrhoeae • Gonococcal arthritis • the most common pathogen (75% of cases) among younger sexually active individuals • Pathogenesis is ultimately a consequence of disseminated gonococcal infection (DGI).
Gonococcal arthritis • Arthritis-dermatitis syndrome includes the classic triad of • dermatitis • tenosynovitis • migratory polyarthritis. • Unlike in S. aureusseptic arthritis, joint destruction is rare low mortality rate.
Gram negative • H .infleunzaoccasionally implicated in preschool children. • Escherichia coli in the elderly, IV drug users and the seriously ill • Salmonella spp. • Pseudomonas aeruginosa or Serratiaspecies cause infection of the sternoclavicular and sacroiliac joints almost exclusively in persons who abuse intravenous drugs.
Gram negative • Aeromonas Persons with leukemia are predisposed . • Pasteurella multocida, Capnocytophaga species (dog and cat bites) • Brucella spp. lumbosacral spine involvement.
Other Acid fast • Mycobacteria are a rare cause of septic arthritis. Anaerobes • usually a consequence of trauma or abdominal infection. • 5% of cases • Fusobacteriumnucleatum • Eikenellacorrodens • Streptococcal species (human bites)
Other Polymicrobial joint infections • 5-10% of cases
Nonsuppurative septic arthritis • Viruses • Fungi • Borrelia burgdorferi
Viruses • Viral infections may cause: • direct invasion rubella virus • production of antigen/antibody complexes. • hepatitis B, • parvovirus B19 • lymphocytic choriomeningitis viruses
Viruses Hepatitis viruses • Hepatitis A • Hepatitis B • Onset in the prodromic stage. • Usually resolves as jaundice develops • Chronic arthritis possible in patients with chronic hepatitis B infection • Hepatitis C