Microbiology

Question 1

What two types of fractures are there?

Answer 1

Direct - high or low energy

Indirect - traction, bending, torsion, bending and torsion

Question 2

What is the treatment for osteomyelitis?

Answer 2

Debridement and antimicrobials

Question 3

What is an open fracture?

Answer 3

When the fracture involves a break in the skin

Question 4

What is non union?

Answer 4

The fracture will not heal

Question 5

What are the most common pathogens involved in osteomyelitis?

Answer 5

Staph aureus and anaerobic gram -ve bacteria

Question 6

Tell me about osteomyelitis coming from diabetic disease

Answer 6

Often contagious
Microneurovascular dysfunction 
Vasomotor dysfunction 
Claw toes 
Often polymicrobial

Question 7

What use is an MRI for osteomyelitis?

Answer 7

To see the infections involvement in the bone

Question 8

What must you wait for in an osteomyelitis case?

Answer 8

Biopsy and culture

Question 9

What antibiotics would be used?

Answer 9

Fluclox and Vancomycin if MRSA

Question 10

A person with tennis shoes steps on a nail, what is the infective organism?

Answer 10

Pseudomonas

Question 11

Who suffers from haematogeneous osteomyelitis?

Answer 11

Prepubertal children
PWID
Central lines, dialysis, elderly (more encounters with healthcare)

Question 12

What are the usual and more unusual pathogens from haematogeneous osteomyelitis?

Answer 12

Staph a
Strep 
Pseudomonas 
Candida 
Eikenella corrondens (needle lickers), mycobacterium TB

Question 13

Dialysis patients have high colonisation rates of what organism?

Answer 13

Staph

Question 14

Where does osteitis pubis affect?

Answer 14

The pubic symphisis

Question 15

What predisposes to osteitis pubis?

Answer 15

Urogynae procedures - lower abdominal pain and pelvic pain

Athletes are predisposed

Question 16

What is Gauchers disease?

Answer 16

Paeds 
Lysosomal storage disorder
May mimic bone crisis
Often tibia 
Sterile if bone crisis 
Deposition of glucocerebroside in cells of the macrophage monocyte system -> deficiency of the enzyme glucocerebrosidase

Question 17

What does SAPHO and CRMO stand for

Answer 17

Synovitis acne pustolosis hyperostosis osteitis - adults

Chronic recurrent multifocal osteomyelitis - kids

Question 18

Tell me about vertebral osteomyelitis

Answer 18

Spondylo
Mostly haematogeneous
May be associated with epidural abscess, psoas abscess
PWID, IV
Presents differently from acute haematogeneous osteomyelitis (only 50% have a fever)

Question 19

Tell me about Pott’s disease

Answer 19

a form of tuberculosis that occurs outside the lungs whereby disease is seen in the vertebrae

Question 20

What are the risk factors for prosthetic joint osteomyelitis

Answer 20

Rheumatoid arthritis, diabetes, malnutrition, obesity

Question 21

What is a sinus?

Answer 21

An opening to the outside

Question 22

What is the mechanism of infection in prosthetic joint osteomyelitis?

Answer 22

Direct inoculation at time of surgery, manipulation of joint at time of surgery, seeding a joint at later time

Question 23

What is an early infection

Answer 23

One which has taken place in the first month

Question 24

What is Panton Valentine Leukocidin

Answer 24

A toxin

Question 25

How long can you use Linezolid to treat?

Answer 25

4 weeks, increases chances of bone marrow failure

Question 26

What is sessile bacteria

Answer 26

Phenotypic transformation of planktonic bacteria (bacteraemia), biofilm, extracellular matrix - now there are two different bacteria in the body, both of which react differently to antibiotics etc

Question 27

Tell me about Rifampicin

Answer 27

Can be hepatotoxin | If given on its own -> Resistance, demonstrating its fragility

Question 28

Treatment of prosthetic joint replacement is?

Answer 28

Remove the prosthesis and cement , therapy for at least 6 weeks, reimplantaion after aggressive antibiotic therapy

Question 29

What does DAIR stand for?

Answer 29

Debridement, antibiotics, implant, retention (mainly in the elderly, not fit enough for other surgery)

Question 30

Name the gram positive organisms that can be involved

Answer 30

Staph aureus Staph epi Propinobacterium acnes - lives in the arm pit

Question 31

Name the gram negative organisms that can be involved

Answer 31

E coli, pseudomonas

Question 32

Septic arthritis might mimic?

Answer 32

Gout - big swollen joint with increased cells

Question 33

What organisms could be involved?

Answer 33

Staph A Strep Neisseria gonorrhoea Haemophilus influenza

Question 34

Where does Bursitis normally affect?

Answer 34

Prepatellar bursa

Question 35

What viruses can affect joints?

Answer 35

Hep B, Parvovirus B19, Rubella virus, Alpha Virus

Question 36

What is pyomyositis

Answer 36

Pus in the muscle

Question 37

What is the main organism?

Answer 37

Staph

Question 38

What organism can lead to disfiguring treatment

Answer 38

C dif, must remove all affected muscle

Question 39

What organism causes tetanus?

Answer 39

Clostridium tetani - gram +ve strictly anaerobic rods

Question 40

what does the neurotoxin cause

Answer 40

Spastic paralysis - binds to the inhibitory neurones, preventing release of neurotransmitters --> Lock Jaw

Question 41

How would you treat tetanus?

Answer 41

Penicillin, metronidazole

Question 42

How long does a derided bone take to be covered by vascularised soft tissue?

Answer 42

6 weeks