O&T Past Paper Flashcards
Bacteriology of septic arthritis (common to uncommon)
- <2 years old
H. influenza, S. aureus
Strep. pneumoniae, E.coli
Strep. pyogene, Group B strep, Proteus, Pseudomonas
Nesseria meningitides
N. gonorrhoeae, Bacteroides
Bacteriology of septic arthritis (common to uncommon)
- Around 2 years old
S. aureus
S. pneumoniae, E. coli
Strep. pyogene, Group B strep, Proteus, Pseudomonas/ Haemophilus
Nesseria meningitides
N. gonorrhoeae, Bacteroides
Bacteriology of septic arthritis (common to uncommon)
- >2 years old
S. aureus*, S. pyogenes
S. pneumoniae, E. coli
Haemophilus, Proteus
Nesseria meningitides
N. gonorrhoeae, Bacteroides
Complications of septic arthritis
- Immediate
- Delayed
Immediate: systemic sepsis, death.
Delayed: premature OA, joint deformity/stiffness, closure of physeal plate and growth disturbance (leg length discrepancies), pathological fractures, chronic or persistent infection.
A baby girl of age 3 months old presented with decrease of movement of the left lower limb. She was a premature baby, born at 32 weeks of gestation, had history of multiple blood taking at femoral vein. There was fever and she refused to feed for 3 days. The baby screamed when her left knee was flexed.
What is the most likely cause of the problem?
Septic arthritis of left hip joint
Abnormalities on XR for septic arthritis?
Early (normal)
Delayed (soft tissue swelling, loss of tissue planes, widening of radiological joint space, slight subluxation (due to effusion))
Late (narrowing and irregularity of joint space, vertebral end-plate disruption)
What investigations would you order for septic arthritis apart from Xray?
Blood – CBC with differential, CRP/ESR
Blood for C/ST
Ultrasound – shows joint effusion
Arthrocentesis – for appearance, smear and culture, WBC (>50k/mm3), protein (high) ± glucose (low, <33% serum)
MRI – usually for occult joint arthritis (eg. SIJ, SCJ)
Treatment of 3 month baby with septic arthritis of hip?
1) Resuscitation and Maintain Vitals
2) IV Antibiotics:
Empirical broad-spectrum 3rd generation cephalosporin (eg. ceftriaxone) until C/ST available
→ then change to specific Abx
→ change to oral Abx when CRP normalize
3) Urgent Open or Arthroscopic Arthrotomy – joint decompression, drainage, lavage
A 30-year-old man with Hx of trauma and IVDU presented with low back pain for 1 week and low-grade fever.
L-spine X-ray: destruction in inferior border of L3 and superior border of L4
Groin region shows injection ‘holes’.
Give TWO possible causes for low back pain
Trauma causing herniated intervertebral disc;
Pyogenic spondylitis
Five investigations for IV addict, 30 year old man with lower back pain for 1 week with fever.
Blood – CBC with diff, ESR, CRP
Blood culture
MRI – for diagnosis and assessment of disease extent (eg. assessment of neurological involvement)
CT-guided biopsy – for C/ST and AFB smear/culture
(Bone scintigraphy) Gallium bone scan
Tests for TB – IGRA, tuberculin skin test
Two treatment options for IV addict, 30 year old man with lower back pain for 1 week with fever.
Conservative – Abx alone (3rd generation cephalosporin + aminoglycoside/quinolone for IVDU), IV until CRP normalizes then oral for 3mo
Surgery – if open Bx needed, decompression of clinically significant abscess
- Indications: failed medical Tx, neurological deficits or progressive deformity or instability
Which joints are commonly affected in rheumatoid arthritis?
Small joints – PIP, MCP, wrist Large joints – knee, ankle, elbow, shoulder Cervical spine (rheumatoid spondylitis)
Which joints are commonly affected in osteoarthritis?
Weight-bearing joints – hips, knees, C- and L-spine
Small hand joints – PIP, DIP, 1st MCP, trapezioscaphoid joint
Where does tennis elbow affect? (1)
Lateral epicondyle – affects extensor and stabilizer of wrist (extensor carpi radialis brevis)
Where does golfer elbow affect? (1)
Medial epicondyle – flexors and pronators of wrist
