Brainscape's Knowledge GenomeTM

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


See full index

A - MSRA - Dermatology [3] > Necrotising Fasciitis > Flashcards

Necrotising Fasciitis Flashcards

1
Q

What is necrotising fasciitis?

A

An uncommon but life-threatening infection, defined as a necrotising infection involving any layer of the deep soft tissue compartment

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

What parts of the deep soft tissue compartment can be affected in necrotising fasciitis?

A
  • Dermis
  • Subcutaneous tissue
  • Fascia
  • Muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How do organisms spread to cause necrotising fasciitis?

A

From subcutaneous tissue along the superficial and deep fascial planes

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

What facilitates the spread of bacteria in necrotising fasciitis?

A

Bacterial enzymes and toxins

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

What is the effect of deep fascial infection?

A
  • Vascular occlusion
  • Ischaemia
  • Tissue necrosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens to superficial nerves in necrotising fasciitis?

A

They are damaged causing a characteristic localised anaesthesia

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

How are the causative organisms of necrotising fasciitis classified?

A

Into 4 types

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

What is Type 1 cause of necrotising fasciitis?

A

Polymicrobial infection with aerobic and anaerobic bacteria

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

Who is Type 1 necrotising fasciitis usually seen in?

A

Immunocompromised or patients with chronic disease

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

What is the causative organism in Type 2 necrotising fasciitis?

A

Group A streptococcus

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

Who does Type 2 necrotising fasciitis occur in?

A

Any age group and otherwise healthy individuals

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

What is the underlying cause of Type 3 necrotising fasciitis?

A

Gram -ve monomicrobial infection

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

What is a usual cause of infection Type 3 necrotising fasciitis?

A

Marine organisms after seawater contamination of wounds, fish fin/sting injuries and raw seafood consumption

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

What is an example of a marine organism that can cause Type 3 necrotising fasciitis?

A

Vibrio vulinficus

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

What causes Type 4 necrotising fasciitis?

A

Fungal infection

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

What are the risk factors for developing necrotising fasciitis?

A
  • Skin injury
  • Underlying conditions
  • Varicella zoster infection (in children)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What types of skin injury can lead to necrotising fasciitis?

A
  • Insect bite
  • Trauma
  • Surgical wounds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What underlying conditions can increase risk of necrotising fasciitis?

A
  • Alcohol abuse
  • IV drug abuse
  • Chronic liver or renal disease
  • Diabetes
  • Malignancy
  • Immunosuppression
  • TB
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the most common type of necrotising fasciitis?

A

Type 1

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

What percentage of necrotising fasciitis cases are caused by Type 1 infections?

A

70-80%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Why is early diagnosis of necrotising fasciitis difficult?

A

It often looks like a superficial skin infection early on

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

When should you have a high index of suspicion for necrotising fasciitis?

A

When the patient is systemically unwell or has disproportionate pain

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

Although it can affect anywhere, what parts of the body does necrotising fasciitis usually involve?

A
  • Extremities
  • Trunk
  • Perineum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the usual time course for necrotising fasciitis?

A

Develops over a few days but potentially much quicker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
In typical necrotising fasciitis development, what happens over days 1-2?
- Local severe pain - Swelling and erythema - Poorly defined margins - No response to antibiotics - Systemic illness
26
Why does necrotising fasciitis cause only local pain, swelling and erythema initially?
The necrotising infection is deep and so not visible
27
What features can distinguish necrotising fasciitis from cellulitis in the first 2 days?
- Disproportionate pain - No response to antibiotics - Lymphangitis is rare - Systemic illness
28
What symptoms of systemic illness can be seen in the first few days of necrotising fasciitis?
- Malaise - Tachycardia - Fever - Dehydration
29
What may be seen in days 2-4 of typical necrotising fasciitis?
- Tense oedema beyond erythema - Possibly haemorrhagic bullae - Discoloured skin progressing to grey necrosed skin - Subcutaneous tissue feels wooden - Pain progress to anaesthesia
30
What happens in days 4-5 of necrotising fasciitis?
- Hypotension and septic shock | - Patient becomes confused and apathetic
31
What is Fornier's gangrene?
A rapidly progressing form of infective necrotising fasciitis of the perineal and genital regions leading to thrombosis of the small subcutaneous vessels and necrosis of the skin
32
How is necrotising fasciitis diagnosed?
Clinically
33
What is required if necrotising fasciitis is suspected clinically regardless of other test results?
Surgical exploration
34
What can sometimes be seen and act as a diagnostic tool on plain x-ray?
Gas or bullae
35
What macroscopic features can confirm necrotising fasciitis on surgical exploration?
- Grey necrotic tissue - Lack of bleeding - Thrombosed vessels - 'Dishwater pus' - Lack of resistance to finger dissection - Non-contracting muscles
36
What test can help to identify necrotising fasciitis if the clinical picture is uncertain?
- Blood tests - Bedside finger test - Microbiology - Radiology
37
What blood tests can help to identify necrotising fasciitis?
- Leukocytosis - Acidosis - Altered coagulation profile - Hypoalbuminaemia - Abnormal renal function
38
What is a bedside finger test for necrotising fasciitis?
- 2cm incision down to deep fascia under local anaesthetic
39
What are the signs of necrotising fasciitis on bedside finger testing?
- Lack of bleeding - Malodorous 'dishwater pus' - Lack of tissue resistance to blunt dissection
40
What microbiological tests can be useful for necrotising fasciitis?
- Blood cultures | - Wound swab
41
What radiological investigations can help to diagnose necrotising fasciitis?
- Plain X-ray - CT - MRI - USS
42
What can be seen on a CT or -ray in some cases of necrotising fasciitis?
Tissue gas
43
What can be sometimes seen on MRI in necrotising fasciitis?
Extent of tissue involvement
44
What can sometimes be seen on USS in necrotising fasciitis?
Subcutaneous gas
45
Why is imaging not always useful in necrotising fasciitis?
There are often false negatives
46
What are the differentials for necrotising fasciitis?
- Cellulitis - Erysipelas - Pyoderma gangrenosum - Limb ischaemia or compartment syndrome - Deep vein thrombosis - Thrombophlebitis - Osteomyelitis
47
What treatment for necrotising fasciitis is essential?
Early and aggressive debridement of involved tissue
48
What are other important aspects of necrotising fasciitis management?
- Resuscitation - Antibiotics - Post-debridement surgery
49
Why may patients with necrotising fasciitis require resuscitation?
They are often shocked or haemodynamically unstable
50
Where is it often appropriate to treat patients with necrotising fasciitis?
Intensive care
51
What is important to ensure when surgically debriding necrotising fasciitis?
Adequate margins with no infected tissue remaining
52
What must happen after initial debridement of necrotising fasciitis?
Wound monitoring and daily debridement of recurring infection
53
When can necrotising fasciitis wounds be dressed?
Once the infection is controlled
54
How are necrotising fasciitis wounds closed?
By secondary suturing with or without skin grafts
55
What may assist healing of necrotising fasciitis wounds?
Vacuum assisted wound closing devices
56
How should antibiotics be started in necrotising fasciitis?
Immediately start IV broad-spectrum at high doses
57
What organisms should be covered by antibiotics for necrotising fasciitis?
- Streptococci - Staphylococci - Gram-ve rods - Anaerobes
58
What support is required in necrotising fasciitis?
- Fluid | - Nutrition
59
When should prophylactic treatment be given to patient contacts?
When there is GAS infection
60
What prophylactic treatment should be given to all contacts of a person with GAS necrotising fasciitis?
Advice about symptoms and when to seek help
61
When should prophylactic antibiotics be given to contacts of GAS necrotising fasciitis?
- Neonates and mothers if either have invasive GAS - Close contacts with symptoms of localised GAS - Household if 2 or more cases of invasive GAS in 1 month
62
What are some symptoms of localised GAS infection?
- Sore throat - Fever - Skin infection
63
What is the first choice antibiotic in necrotising fasciitis?
- Penicillin V
64
What are the potential complications of necrotising fasciitis?
- Septic or toxic shock - Tissue necrosis - Nerve damage - Muscle necrosis - Skin grafting - Reconstructive surgery - Amputation

A - MSRA - Dermatology [3] (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions