OSTEOMYELITIS & SEPTIC ARTHRITIS Flashcards
How the pathogen reach the bone ?
1- Hematogenous route 2- Contiguous soft tissue focus ( post operative infection, contaminated open fracture, soft tissue infection , puncture wounds)
3- In association with peripheral vascular disease (diabetes mellitus ,severe atherosclerosis, vasculitis)
• May have a short duration ( few days for hematogenous acquired
infection) or may last several weeks to months ( if secondary
to contiguous focus of infection).
S. aureus, group B Streptococcus,Gram negative rods (eg. E. coli, Klebsiella ).
Common in ?
Infants
S. aureus, group A Streptococcus & H.
influenzae
Common in ?
Children
S. aureus
Common in ?
Adults
Salmonella species
Common in?
Sickle cell disease
S. aureus, group A Streptococcus, Gram
negative rods, anaerobes.
Common in >
Infection after trauma ,injury or surgery
Pseudomonas aeruginosa, S. aureus
Common in ?
Infection after puncture wound of foot.
Mycobacterium tuberculosis or M. avium.
AIDS patients
acute osteomyelitis
Clinically?
fever, localized pain , heat , swelling, tenderness of affected site ( one or more bones or joints affected in hematogenous spread). May be local tissue infection ( abscess or wound) .
acute osteomyelitis
Blood tests:?
leukocytosis, high ESR and C-reactive
protein.
acute osteomyelitis
• X-ray? Ultrasound? CT scan? MRI?
• X-ray : normal at early stages. Swelling of soft tissues
followed by elevation of periosteum , demineralization and
calcification of bone later on.
• Ultrasound: fluid collection (abscess) and surface
abnormalities of bone. • CT scan: reveal small areas of osteolysis in cortical bone. • MRI : early detection ,help in unclear situations. Defines
bone involvement in patients with negative bone scan.
Diagnosis of acute osteomyelitis?
Blood culture: bacteremia common.
Biopsy of periosteum or bone or needle aspiration of
overlying abscess if blood culture is negative.
Blood test: complete blood and differential counts .
Erythrocyte sedimentation rate ( ESR) .
C-reactive protein
Imaging studies: X-RAY, MRI, CT-SCAN
Complications of acute osteomyelitis include?
oSeptic arthritis
oChronic osteomyelitis
oMetastatic infection to other bones or organs
oPathological fractures
Chronic Osteomyelitis
Infection due to?
hematological spread is rare.
Chronic Osteomyelitis
Infection are ?
secondary to a contiguous focus or
peripheral vascular disease.