Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Year 2 - Musculoskeletal (DP) > Microbiology > Flashcards

Microbiology Flashcards

1
Q

What organisms are typically involved in a prosthetic joint infection?

A

Coagulase negative Staph
Staph aureus
Strep spp
Propionibacterium acnes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What organisms typically cause septic arthritis?

A

Staph aureus

Strep spp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What organisms tend to be responsible for post-traumativ infections?

A

Staph aureus
Polymicrobial
Coliforms
Pseudomonas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What bacteria are often involved in vertebral osteomyelitis?

A

Staph aureus
Coliforms
Strep spp
Mycobacterium tuberculosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What organisms typically cause diabetic foot infections?

A 
Staph aureus
Strep spp
Coliforms
Pseudomonas
Anaerobes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What bacteria is a less common infective organism but is more common in kids under 5 years old?

A

Kingellin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

A 3 year old child presents with pain in his right hip. his mother says he hasn’t been feeding very well. On examination his temperature is 39.1, and there is obvious swelling and erythema over his right hip. Any attempt to touch or move the hip is met with obvious pain.

A

Acute bone and joint infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do we classify Systemic Inflammatory Response Syndrome (SIRS)?

A

Two or more of:

- Temperature >38 or 20 or PaCO2 12,000 cells/mm^3 OR 90

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are some rarer causes of septic arthritis?

A

Haemophilus influenzae

Neisseria gonorrhoea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When would a blood culture be carried out?

A

If the patient is pyrexial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the empiric treatment for septic arthritis in:

  1. Adults
  2. Kids
A
  1. High dose flucloxacillin

2. High dose flucloxacillin and ceftriaxone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How long does septic arthritis treatment continue?

A

2-4 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is osteomyelitis?

A

Inflammation of bone and medullary cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where does osteomyelitis tend to occur?

A

Long bones

Vertebrae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are acute causes of osteomyelitis?

A

MSSA

Strep spp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What bacteria may cause chronic osteomyelitis?

A 
Mycobacterium tuberculosis
Pseudomonas
Salmonella
Brucella
Coliforms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How long does acute osteomyelitis last?

A

Few days to

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How might osteomyelitis spread into the joint space?

A

Since metaphysis is intracapsular in these joints:

 - Shoulder
 - Ankle
 - Hip
 - Elbow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why are infants at an increased risk of septic arthritis after osteomyelitis?

A

Vessels cross into epiphysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What processes occur that may lead to chronic osteomyelitis?

A
  1. Abscess
  2. Permanent damage
  3. Septicaemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Why is there not an immediate need for antibiotics in chronic osteomyelitis?

A

SIRS is usually absent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

When would we start antibiotics in chronic osteomyelitis?

A

Once we achieve culture results

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the empiric treatment for osteomyelitis?

A

High dose flucloxacillin:

 - Modify after culture
 - 4 to 8 weeks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which of the following is not a risk factor for a prosthetic joint infection:

 - RA
 - DM
 - Malnutrition
 - URTI
 - Obesity
A

URTI

25
Q

What are the three types of implant infection?

A

Early postoperative (0-3 months)
Delayed (Low grade) (3-24 months)
Late (> 24 months)

26
Q

A patient presents with persistent pain in her left hip. She had a hip replacement 18 months ago. She is a diabetic and has a BMI of 32.

A

Delayed PJI

27
Q

What features of CoNS make them difficult to treat?

A

Produce a biofilm over prosthesis

28
Q

What cultures may aid in the diagnosis of a PJI?

A

Tissue and bone (multiple)

29
Q

How do we treat a PJI?

A

Remove prosthesis and cement
Treat with antibiotics
Wait > 6 weeks until joint is re-implanted

30
Q

How do we treat necrotising fasciitis?

A

Surgical debridement
Empirical antibiotics (Strep pyogenes):
- Penicillin - Kills bacterial
- Clindamycin - Reduces toxin production

31
Q

What bacteria causes gas gangrene?

A

Clostridium perfringens:

 - Gram positive bacilli
 - Strictly anaerobic
32
Q

What is the pathogenesis of gas gangrene?

A
  1. Spores in bowel/environment
  2. Spores move into tissue
  3. Spores germinate
  4. Gas bubble accumulation
  5. ‘Crepitus’
33
Q

What factors predispose to gas gangrene?

A

Dead tissue

Anaerobic conditons

34
Q

How is gas gangrene treated

A
  1. Urgent surgical debridement
  2. High dose antibiotics
    • Penicillin
    • +/- Metronidazole
  3. +/- Hyperbaric oxygen
35
Q

What causes tetanus?

A

Clostridium tetani:

 - Gram positive bacilli
 - Strictly anaerobic
36
Q

Where are the spores that cause tetanus found?

A

Soil
Gardens
Animal bites

37
Q

What happens in tetanus?

A
  1. Neurotoxin produced
  2. Neurotoxin binds to inhibitory neurones
  3. Neurotransmitter release prevented
  4. Spastic paralysis
38
Q

Are the bacteria that cause tetanus invasive?

A

No

All toxin driven

39
Q

How is tetanus treated?

A 
Surgical debridement
Antitoxin
Supportive measures
Antibiotics:
     - Penicillin
     - Metronidazole
Booster vaccine:
     - 2, 3 and 4 months
40
Q

What are the choice antibiotics for Staph and Strep?

A

Flucloxacillin
Vancomycin
Clindamycin

41
Q

What other uses exist for vancomycin?

A

Diphtheroids
CoNS
MRSA
If penicillin allergic

42
Q

What is clindamycin effective in?

A

Antitoxin:

 - PVL
 - GAS
43
Q

What antibiotic choices treat coliforms?

A

Gentamicin
Cephalosporins:
- Ceftriaxone
Sometimes PO ciprofloxacin

44
Q

What is a biofilm composed of?

A

Protein

Polysaccharide

45
Q

What does a biofilm do?

A

Protects bacteria from:

 - Immune system
 - Antibiotics
46
Q

What environment does a biofilm produce?

A

Low pH - 5
Reduced oxygen
Free nucelic acids

47
Q

What is the Tayside Protocol for PJI?

A
  1. No pre-op antibiotics
  2. Minimum three bone/tissue/pus culture samples
  3. Minimum 6 weeks antibiotics before clean surgery
48
Q

Why do we take three bone samples for culture?

A

Superficial swabs useless
Bone samples can be contaminated with skin flora
Some infections caused by skin flora:
- eg. CoNS

49
Q

What is the Tayside Protocol for PJIs caused by gram positive bacteria?

A

Flucloxacillin
If penicillin allergic - Vancomycin
If MRSA - Teicoplanin

50
Q

What is the Tayside Protocol for PJIs caused by gram negative bacteria?

A

Cot-trimoxazole OR
Amoxicillin OR
Ciprofloxacin OR
Ceftriaxone

51
Q

How long do the following antibiotic treatments last:

  1. DAIR (Debridement, Antibiotics, Irrigation, Retention of prosthesis)
  2. One stage
  3. Two stage
  4. Hip PJI
  5. Knee PJI
A
  1. 4 weeks IV then 8 weeks PO
  2. 4 weeks IV then implant then 8 weeks PO
  3. 6 weeks IV then 6 weeks nothing then implant
  4. Treatment minimum 3 months
  5. Treatment minimum 6 months
52
Q

How can we assess response in PJI?

A

Repeat MRI/CT

53
Q

How long til we can be sure a PJI has been cured?

A

> 2 years

54
Q

What are the general principles for surgical prophylaxis (SIGN 104)?

A
  1. 1st dose within 60 minutes of start of procedure
  2. Prophylaxis should not last > 24 hours
  3. Needs to be in tissue at time of surgery and cover relevant pathogens
55
Q

When is surgical prophylaxis used in orthopaedics?

A

Prosthetic joint implant:
- Co-amoxiclav
> 1.2g peri-operatively
> Plus two post-operative doses

56
Q

What do we do if MRSA is discovered pre-op?

A

Decolonise

Restart peri-op antibiotics

57
Q

What surgical prophylaxis is used if a patient is penicillin allergic?

A

Co-trimoxazole

58
Q

What type of vaccine is used to prevent tetanus?

A

Toxoid

59
Q

If a patient was bitten by a dog during a trip to India what other vaccination should be considered?

A

Rabies

Year 2 - Musculoskeletal (DP) (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions