Osteomyelitis Flashcards
(10 cards)
What is Osteomylitis
Inflamattion of the Bone tissue caused by infecting organism (Commonly Staph Aures)
Either Heamotagenous (originating from distant source and spreading to bloodstream = Bacteriamia ) or Contigious (spread from adjecnt soft tissue infection or trauma)
Detail the Charecteristics of Heamotagenous OM
Follows Bacteriaemia spread from the blood
Most common in Children - Long Bones
Middle aged Adults who use IV drugs - Vertebrae and Scroiliac joints
Elderly - Vertebrae
Why is Heamotagenous OM more common in children
There is increased blood flow at the metaphysis and there highly vascular making them more susceptible to bacteria seeding
Immature immune system making them more susceptible to bloodstream infection that might spread to the bone.
Children’s bones have loops and slower blood flow near the growth plates (epiphyseal plates) an ideal environment for bacteria to settle, multiply, and cause infection.
What are Acute OM and Chronic OM
Acute = Newly Recognised
Presnting 1 week after symptomns
Local infection and inflammation + systemic illness
Servere pain localised pain
Chronic = Relapse of previously treated/untreated infection
Clinical signs last for more than 10 days
Usually mild or intermitent pain
Presence of Pus, Microorganims and Dead tissue with a compromised soft tissue envelope
Provide a detailed breakdown of the assesment of this patient:
- Patient with a ‘sore toe’ with increasing pain over the last 2 weeks
- Generally feeling unwell
- Previous surgery to the toe last year
- Previous ‘sore’ on that toe got better but has returned and worsening.
- Completed a 10-day course of antibiotics prescribed by her GP (Flucloxacillin 500 mg four times a day) but it hasn’t settled GP made referal to Podiatry
Detailed patient History:
* (previous infection may have been dormant for moths before reoccuring) Previous treatment Surgical/Antibiotics, Duration and nature of symptomns
Local examintaion:
* Inspect for inflammation, swelling, erythema, tenderness, warmth, presence of a sinus, or discharge. Check for any deformities, signs of ulceration, or previous surgical scars.
Vascular + Neurological assesment:
* Assess circulation (pulses, ABPI) and sensation (monofilament or tuning fork tests) to rule out peripheral neuropathy or vascular insufficiency, especially in patients with diabetic risks.
Lab assesment :
* Inflamattory markers i.e CRP, WHite Blood cell, ESR
* Deep Tissue Biopsy to determine causative pathogen and guide antibiotic therapy.
Radiographic assesment:
* X ray initially to check for evidence of osteopenia, sequestration, involucrum, cortical destruction, or other radiographic signs of osteomyelitis
* MRI provides detailed soft tissue and bone marrow images to confirm diagnosis and extent of infection
Provide a detailed breakdown of the Diagnosis of this patient providing rationale for your diagnosis:
- Patient with a ‘sore toe’ with increasing pain over the last 2 weeks
- Generally feeling unwell
- Previous surgery to the toe last year
- Previous ‘sore’ on that toe got better but has returned and worsening.
- Completed a 10-day course of antibiotics prescribed by her GP (Flucloxacillin 500 mg four times a day) but it hasn’t settled GP made referal to Podiatry
Chronic Osteomyilitis
The patient’s symptoms—persistent pain, systemic unwellness despite antibiotic treatment, and previous surgical history—strongly suggest chronic osteomyelitis. The non-resolving nature of her infection despite antibiotics is consistent with chronic osteomyelitis, often complicated by biofilm formation rendering antibiotic treatment ineffective without surgical intervention.
What is Biofilm and why are some antibiotics not effective against it
A biofilm is a structured bacterial community that adheres to surfaces, communicates via cell-to-cell signals.
Some bacteria within the Biofilm enter a dormant state, evading antibiotics that target cell division and gaining partial protection from the host immune system within the glycocalyx
How is Chronic OM charecterised
Devitalised Bone (Sequestra)
Formation of New Bone (Invulcrum)
Polymicrobial (mixed gram + gram - anerobes)
Sinus tract
Normal or mild white blood cell count ESR and CRP usually elevated
What are the common differential diagnosis of Osteomyilitis
Cellulitus
Gachuers disease (Bone infarction and marrow expansion)
Septic Arthrits
Sickle cell crisis (Vasoocclusive red blood cells)
Acute Charcot
How do you diffrentiate between Osteomylitis and septic arthritis
So gold standard diagnositc protocol is to perform an arthrocentesis (Joint aspiration) and send the synovial fluid off for culture looking at esr crp and in particular white blood cell counts which are often raised in septic arthritis but can be normal with chrocnic om
