Transcript Septic arthritis

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
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Diabetes
Hemodialysis
Injected drug use
Poor blood supply
Recent trauma
Surgery
The elderly
Symptoms
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Bone pain
Fever
malaise
Local swelling, redness, and warmth
Other symptoms may occur :
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Chills
Excessive sweating
Low back pain
Swelling of the ankles, feet, and legs
Classification
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Bacterial:
– Acute osteomyelitis (subacute)
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hematogenous
non- hematogenous
– Chronic osteomyelitis
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Nonspecific
specific (TB, syphilitic)
• Non- Bacterial
– Viral osteomyelitis
– Fungi
– Radiation osteomyelitis
Acute hematogenous osteomyelitis
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mostly children
history of trauma
Long bone >> most common
In children >> metaphysis
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Most vascular part
Blood flow slow
Most part subject to trauma
In adult >> epiphysis
The organisms
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Gram +ve
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Staphylococus aureus (80-90%)
Strep. pyogen
Strep. pneumonie
Gram -ve
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Haemophilus influnzae (50% < 4 y)
E .coli
Pseudomonas auroginosa,
Proteus mirabilis
Source Of Infection
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Infected umbilical cord in
infants
Infection
( respiratory, intestinal,
urinary, oral, boils,
tonsilitis, skin
abrasions)>> bacteramia
Traumatic implantation
Pathology
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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 fractured bone
– 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
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Haematogenous osteomyelitis .
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Contagious spread osteomyelitis.
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Peripheral vascular disease.
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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
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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
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supportive treatment for pain
antibiotics
surgery
Let’s continue with
Samar
Joint infections
Samar
Shaheen
Joint infections
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
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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
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fever
swelling
warmth
inability to move the
limb with the
infected joint
• severe pain in the
affected joint,
especially with
movement
Septic arhritis
Suppurative septic arthritis
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Caused by bacteria
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Virtually every bacterial organism has been
reported to cause septic arthritis.
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Bacterial species causing septic arthritis vary
with the age of the patient.
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The most common species overall is S. aureus
Neisseria gonorrhea is the most common cause in
sexually active adults
H. infleunza occasionally 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.
Bacterial causes
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. aureus septic arthritis, joint
destruction is rare  low mortality rate.
Gram negative
• H .infleunza occasionally implicated in preschool
children.
• Escherichia coli in the elderly, IV drug users
and the seriously ill
• Salmonella spp.
• Pseudomonas aeruginosa or Serratia
species 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
• Fusobacterium nucleatum
• Eikenella corrodens
• 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
Viruses
Parvovirus B19
• Occurs in adults esp. women
• Mainly involves the small joints of the
hands and feet bilaterally.
Rubella (natural infection and vaccine related)
– Onset possible before, during, or after the
appearance of the rash
– Mild, short lived and without major impairment
of joint function.
Viruses
HIV
• 2 types occur, both with
noninflammatory sterile joint fluid
Mumps
• Occurs in adult men 2 weeks after the
presentation of parotitis
• Mild, short lived and without impairment
of joint function.
Fungi
• Candida albicans
• Sporothrix schenckii
• Coccidioides immitis, Histoplasma
species, and Blastomyces species
Borrelia burgdorferi
Spirochete
• Borrelia burgdorferi .
– Lyme arthritis
– Develops in 60%-80% of untreated patients.
– The dominant feature of late disease (stage
3)
– may produce nonsuppurative joint infection
– Borrelia antigens cross react with proteins
in the joints
Reactive arhtritis
• Acute inflammation of the joints that follows
infection with various bacteria, but the joints are
sterile.
• i.e. inflammation is a “reaction” to the presence
of bacterial antigen elsewhere in the body.
• Usually oligoarticular and asymmetric.
• Bacterial infection precedes the arthritis by a few
weeks.
Reactive arhtritis
• Antibiotics have no effect
• Anti-inflammatory agents are typically
used.
• Increased risk in persons with HLA-B27
locus
• Thought to be immunologically
mediated.
• Reiter’s syndrome icludes reactive
arthritis, but affects multiple organs.
Reactive arhtritis
• Reactive arthritis is associated with:
– Enteric infections
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Salmonella spp.
Shigella spp.
Campylobacter spp.
Yersinia spp
– urethritis
• Chlamydia trachomatis
Reiter’s syndrome
• The syndrome is characterized by the triad of:
– Arthritis
– Conjunctivitis
– Urethritis
• Infection by one of the following predisposes to
the disease:
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Salmonella spp.
Shigella spp.
Campylobacter spp.
Yersinia spp
Chlamydia trachomatis
Diagnosis
Septic arthritis
• Joint fluid aspiration
– Microscopy
• Absence of crystals to rule out gout &
pseudogout
– Culture
Diagnosis
Reactive arthritis
• Clinically: a history of previous infection
in the intestinal or genitourinaty tract.
• RF is usually negative.
• The HLA-B27 gene marker blood test can
be helpful.
R E L A X…
LIFE IS
BEAUTIFUL…