Bone and Joint infections Flashcards
How does septic arthritis present?
Hot swollen painful joint
Erythema, tenderness, reduced ROM
Investigation and treatment steps for septic arthritis?
- Aspiration – gram staining, crystal microscopy, culture and antibiotic sensitivities
- Emperical Antibiotics - Flucloxacillin + rifampicin
- Blood cultures
- MRI
- Workup for sepsis / severity
- Repeat aspiration/ Washout
Native joint Septic arthritis most commonly affect which joints?
Knee > Hip > shoulder
Native joint Septic arthritis usally occurs due to? (2)
Haematogenous and/or Iatrogenic
List 4 causitive organisms in native joint septic arthritis
- Staphylococcus aureus incl MRSA
- Streptococci
- Gram negatives in Immune deficiency, urinary or intestinal invasive procedures, elderly people, renal failure, chronic joint disorders and diabetes
- Gonococci , Borrelia ( Lyme ) & TB
First line emperical antibiotics for gram positive bacteria?
Flucloxacillin + Benzylpenicillin
First line emperical antibiotics if there is an MRSA risk?
Vancomycin/ Teicoplanin
Duration of antibiotic treatment in native joint spetic arthritis
Upto 6 weeks from last positive culture
2-3 weeks IV followed by oral
What is the first thing we MUST do if we suspect a Prosthetic Joint Infection?
ALWAYS SEEK ORTHOPAEDIC OPINION
What defines an ‘early’ Prosthetic Joint Infection?
< 30 days
List 4 causitive organisms in Prosthetic Joint Infections
- Staphylococcus aureus including MRSA
- Coagulase negative staphylococci
- Streptococci
- Gram negatives – enterobacteriaceae
+ Other gram positives… it is rarely fungal
List 3 management steps for prosthetic joint infections?
DAIR
Debridement, Antibiotics, Implant Retention (one vs two stage revision)
What does DAIR stand for in management of prosthetic joint infections?
Debridement, Antibiotics, and Implant Retention
Compare 2 stage vs 1 stage revision in the management of prosthetic joint infections
Two stage revision : Removal of the prosthesis, then delayed reimplantation, typically 6-8 weeks later
One stage revision : Removal of the prosthesis, then immediate reimplantation of a new prosthesis
Emerical antibiotic treatment for PJI?
Vancomycin or Teicoplanin + Tazocin/meropenem
Following cultures what other antibiotic may be used?
Rifampicin if organism is susceptible
Duration of antibiotic treatment for PJI?
IV antibiotics for 6 weeks followed by oral antibiotics
Oral antibiotics 6 weeks - 4 1/2 months
Acute osteomyelitis is usually aquired via what route
cjeck?
haematogenous
Subacute osteomyelitis is known as what?
Brodie’s abscess
Compare the onset and characteristics of acute vs chronic osteomyelitis
Acute: typically presents 2 weeks after bone infection, characterised by inflammatory bone changes
Chronic: typically presents 6+ weeks after bone infection, characterised by the presence of bone destruction and formation of sequestra
How do we diagnose oteomyelitis? (4)
- Blood cultures
- Sinus track cultures/superficial ulcer swabs (usually do not correlate with cultures obtained at bone biopsy)
- Bone biopsy for histology and culture
- Imaging
What principals must we address for use of Antibiotics in osteomyelitis?
- Depends on risk factors
- Gram positive cover essential
- If not septic wait to get samples
Duriation of antibiotic treatment for osteomyelitis?
Usually 6 weeks IV antibiotics followed by 6 weeks oral antibiotics
Surgical management of osteomyelitis?
Drainage of abscess / debridement
Spinal instability : fixation
Amputation in context of diabetic foot infections
What is OPAT?
Out-patient Parenteral Antibiotic Therapy
Service to manage patients with severe non-life threatening infections requiring parenteral antibiotics in an ambulatory setting. Aims to reduce length of stay for complex infections or avoid admissions in other simpler infections
List 3 benefits of OPAT
- Home treatment - patients can recover in familiar surroundings
- Hospital beds and nursing time gained
- Indirect benefits - cost savings
e.g. income to the acute trust from further admissions into the bed vacated through the use of OPAT, reduced cancellations of operations, improvements in efficiency of bed use and patient flow
