Cellulitis

Question 1

Cellulitis refers to an infection of the skin. Can this occur anywhere in the body?

Answer 1

• yes
• typically presents in the limbs though

Question 2

Cellulitis occurs when bacteria are able to penetrate the skin. In cellulitis, which layers of the skin are affected?

1 - epidermis (all cellular layers)
2 - dermis (hair follicles, nerve endings, glands, blood vessels and lymphatics)
3 - hypodermis (subcutaneous fat, connective tissue anchoring to basement membrane)
4 - all of the above

Answer 2

4 - all of the above

Question 3

Cellulitis is a very common presentation in acute medicine. What is the incidence of cellulitis?

1 - 15 / 100,000
2 - 150 / 100,000
3 - 1500 / 100,000
4 - 15,000 / 100,000

Answer 3

4 - 15,000 / 100,000

Question 4

Cellulitis is a skin infection, typically caused by bacteria that affects all layers of the skin up to the deeper subcutaneous tissues. What age has a peak incidence of cellulitis?

1 - 20-30
2 - 30-50
3 - 40-60
4 - 50-60

Answer 4

4 - 50-60

Question 5

Cellulitis is a skin infection, typically caused by bacteria that affects all layers of the skin up to the deeper subcutaneous tissues. Are men or women more likely to develop cellulitis?

Answer 5

• affects both equally

Question 6

Cellulitis is a skin infection, typically caused by bacteria that affects all layers of the skin up to the deeper subcutaneous tissues. Infection is typically caused by a break in the skin. All of the following are common risk factors, EXCEPT which one?

1 - previous surgery
2 - immunosuppressed
3 - atopic dermatitis (eczema), Athlete’s foot,
4 - lymphoedema
5 - history of cellulitis
6 - obesity

Answer 6

1 - previous surgery
- may cause a wound infection, typically caused by S. aureus, but not cellulitis

• immunosuppression includes diabetes mellitus, HIV, immunosuppressive drugs

Question 7

Although the exact pathophysiology of cellulitis is poorly understood, exotoxins (proteins secreted by bacteria) have been linked. All of the following can cause cellulitis, but which 2 are most common?

1 - Streptococcus pyogenes
2 - Staphylococcus aureus
3 - Vibrio vulnificus
4 - Methicillin-resistant Staphylococcus aureus (MRSA)

Answer 7

1 - Streptococcus pyogenes
2 - Staphylococcus aureus

Question 8

When examining a patient with suspected cellulitis, are the borders of the infection typically well demarcated?

Answer 8

• no
• as the deeper dermis is affected, it can be difficult to identify the borders of infection

Question 9

Which of the following is NOT a common clinical sign of cellulitis?

1 - fever and malaise (feeling crappy)
2 - cool to touch
3 - redness with swelling
4 - tenderness to touch
5 - sign of broken skin where infection began

Answer 9

2 - cool to touch
- typically presents with warmth to the touch

Question 10

Does cellulitis typically present bilaterally?

Answer 10

• no
• presents unilaterally
• if bilateral, this suggestion other diagnosis

Question 11

Does cellulitis typically present gradually or acutely?

Answer 11

• presents acutely
• if it presents gradually, this suggests a different diagnosis

Question 12

When trying to identify if a patient has cellulitis, we can use history, examinations and investigations. Which of the following is NOT a typically differential for cellulitis?

1 - thrombophlebitis (inflammation causing blood clots to form in veins, mostly in the legs)
2 - DVT and PVD
3 - lymphoedema
4 - contact dermatitis (allergy)
5 - ingrown hair
6 - gout
7 - insect sting, cat scratch disease

Answer 12

5 - ingrown hair

Question 13

Diagnosis of cellulitis is typically a clinical diagnosis. However, all of the following can be useful, EXCEPT which one?

1 - LFTs
2 - U&Es (systemic inflammation may cause AKI)
3 - FBC (WBC may be raised)
4 - CRP and ESR

Answer 13

1 - LFTs
- wouldn’t hurt, but typically does not aid with the diagnosis

• a swab and blood culture may be useful in some patients

Question 14

In a patient with confirmed cellulitis, we would typically wash, clean, moisturise and dress infected area regularly. In addition to this patients would be prescribed oral (IV in severe cases) antibiotics. Which of the following class would be the 1st line treatment in cellulitis in a patient with NKDA?

1 - Glycopeptides
2 - Penicillins
3 - Cephalosporins
4 - Macrolids

Answer 14

2 - Penicillins
- Flucloxacillin 1st line

• Cephalosporins are 1st line if patient has an allergy to penicillins

Question 15

When treating a patient, is it important to draw around the borders of cellulitis, if this is possible?

Answer 15

• yes
• helps identify the response to treatment

Question 16

The severity of cellulitis can be graded using the Eron classification, which is graded from I to IV with increasing severity. At what severity should patients be admitted to hospital?

1 - IV
2 - III
3 - II
4 - I

Answer 16

3 - II
- typically reviewed , but >II

Question 17

Despite treating cellulitis, complications may occur. One of these is bacteraemia. Which one of the following matches the description of bacteraemia?

1 - bacteria from cellulitis has entered the blood stream
2 - abnormal system wide response to an infection that is a medical emergency
3 - infection of the endocardium surrounding the heart
4 - bone marrow become infected

Answer 17

1 - bacteria from cellulitis has entered the blood stream

Question 18

Despite treating cellulitis, complications may occur. One of these is osteomyelitis. Which one of the following matches the description of osteomyelitis?

1 - bacteria from cellulitis has entered the blood stream
2 - abnormal system wide response to an infection that is a medical emergency
3 - infection of the endocardium surrounding the heart
4 - bone marrow becomes inflamed due to infection

Answer 18

4 - bone marrow becomes inflamed due to infection

Question 19

Despite treating cellulitis, complications may occur. One of these is sepsis. Which one of the following matches the description of sepsis?

1 - bacteria from cellulitis has entered the blood stream
2 - abnormal system wide response to an infection that is a medical emergency
3 - infection of the endocardium surrounding the heart
4 - bone marrow becomes inflamed due to infection

Answer 19

2 - abnormal system wide response to an infection that is a medical emergency

Question 20

Despite treating cellulitis, complications may occur. One of these is infective endocarditis. Which one of the following matches the description of infective endocarditis?

1 - bacteria from cellulitis has entered the blood stream
2 - abnormal system wide response to an infection that is a medical emergency
3 - infection of the endocardium surrounding the heart
4 - bone marrow becomes inflamed due to infection

Answer 20

3 - infection of the endocardium surrounding the heart

Question 21

Despite treating cellulitis, complications may occur. One of these is necrotising fasciitis. Which one of the following matches the description of necrotising fasciitis?

1 - bacteria from cellulitis has entered the blood stream
2 - abnormal system wide response to an infection that is a medical emergency
3 - infection of the endocardium surrounding the heart
4 - infection causes necrosis of deep dermis, including subcutaneous fat and muscle

Answer 21

4 - infection causes necrosis of deep dermis, including subcutaneous fat and muscle

Question 22

Necrotising fasciitis is a complication that can be caused by cellulitis where the deep subcutaneous skin layers including muscle and fat are necrosed. Is this dangerous?

Answer 22

• yes
• can develop rapidly, cause limb loss, sepsis and death
• typically affects the limbs

Question 23

Diabetic patients are at risk of recurrent cellulitis. Which of the following can be used to reduce the risk of recurrence?

1 - foot and leg checks
2 - correct footwear
3 - awareness of cellulitis
4 - all of the above

Answer 23

4 - all of the above