Microbiology and the Skin

Question 1

Which organism is responsible for Staphylococcal Scalded Skin Syndrome (SSSS)?

Answer 1

S. aureus

Question 2

When Staphylococcal Scalded Skin Syndrome occurs in a newborn, what is the name of the condition?

Answer 2

Ritter’s disease of the newborn

Question 3

Which type of patient is most at risk of Staphylococcal Scalded Skin Syndrome?

Answer 3

1. Children < 6 years
2. Immunosuppressed
3. Renal failure

Question 4

How does Staphylococcal Scalded Skin Syndrome present?

Answer 4

1. Widespread formation of fluid filled blisters
2. Blisters are thin walled and Nikolsky’s sign +ve
3. Widespread painful erythroderma

Question 5

Which areas of the skin are most affected by Staphylococcal Scalded Skin Syndrome?

Answer 5

1. Face
2. Perineal region
3. Areas where skin rubs together

Question 6

How is Staphylococcal Scalded Skin Syndrome different from Toxic epidermal necrolysis?

Answer 6

Staphylococcal Scalded Skin Syndrome spares the mucous membranes

Question 7

What is the antibiotic of choice against S. aureus?

Answer 7

Flucloxicillin

Question 8

How many types of necrotising fasciitis exist?

Answer 8

2

Question 9

What causes type 1 necrotising fasciitis?

Answer 9

Aerobic or anaerobic bacteria

Question 10

When is type 1 necrotising fasciitis most frequently seen?

Answer 10

Post surgery

Question 11

What causes type 2 necrotising fasciitis?

Answer 11

Group A streptococcal species

(e.g. Strep. pyogenes)

Question 12

Why is Nikolsky’s sign negative in necrotising fasciitis?

Answer 12

Infection spreads into the subcutis and underlying muscle tissue

Question 13

What is a classic sign of necrotising fasciitis on plain X-ray?

Answer 13

Crepitus

(gas produced by bacteria)

Question 14

Why is surgery the only option for necrotising fasciitis?

Answer 14

1. Treatment is required quickly and surgical debridement is necessary
2. There is poor vascualr network due to tissue destruction for antibiotics will not be able to penetrate

(IV antibiotics will still be given with surgery, but never alone)

Question 15

What are the treatments for candida intertrigo?

Answer 15

1. Clotrimazole cream
2. Nystatin
3. Oral fluconazole

Question 16

What is candida intertrigo?

Answer 16

Candidal fungal infection often seen in skin folds

(e.g. under breasts, groin areas, abdominal folds, nappy areas)

Question 17

Which microorganism causes toxic shock syndrome?

Answer 17

S. aureus

Question 18

Why is Toxic shock syndrome associated with young women?

Answer 18

It is associated with the use of high absorbancy tampon use

Question 19

Which type of rash is associated with toxic shock syndrome?

Answer 19

Diffuse scarlatiniform rash which later desquamates

(clearly present on palms and soles)

Question 20

Where does the rash associted with toxic shock syndrome normally manifest?

Answer 20

1. Palms and soles
2. Accentuation in skin folds
3. Inguinal folds/perineal area

Question 21

What are the main symptoms of toxic shock syndrome?

Answer 21

1. Hypotension
2. Shock
3. Hyperaemia of mucous membranes
4. Pharyngitis
5. Strawberry tongue
6. Skin/muscle tenderness
7. Oedema of hands/feet

Question 22

What is dermatophyte infection?

Answer 22

Fungal infection causing ringworm

Question 23

By which three methods is dermatophyte infection diagnosed?

Answer 23

1. Clinical appearance
2. Skin scaping s and culture
3. Woods light

Question 24

Which group of Streptococcus is associated with neonatal meningitis?

Answer 24

B

Question 25

What is Mucormycosis?

Answer 25

Any fungal infection in the order Murcorales Characterised by hyphae growing in and around blood vessels

Question 26

In which patients may Mucormycosis be life threatening?

Answer 26

1. Diabetic 2. Immunocompromised

Question 27

What do dermatophytes require for growth?

Answer 27

Keratin

Question 28

How is an infection with sarcoptes scabiei treated?

Answer 28

1. Benzyl benzoate (adults, not children) 2. Malathion lotion (applied overnight and washed off)

Question 29

Strep. pyogenes can be treated with which antibiotics?

Answer 29

Flucloxicillin or penicillin

Question 30

In diabetic patients with severe leg ulcers, what treatment should be given for anaerobic cover?

Answer 30

Metronidazole

Question 31

Which bacterial species is known to cause UTIs in women of child bearing age?

Answer 31

Staph. saprophyticus

Question 32

Tinea pedis affects which part of the body?

Answer 32

Fungal infection of the foot | (athletes' foot)

Question 33

Which resident bacterial species is associated with acne and is present on the upper arm and axillae?

Answer 33

Proprionobacterium

Question 34

Which group of Strep is associated with throat/skin infections?

Answer 34

A

Question 35

Strep pneumoniae and Strep viridans are ______ haemolytic

Answer 35

Strep pneumoniae and Strep viridans are **alpha** haemolytic

Question 36

MRSA cannot be treated with which common antibiotic?

Answer 36

Flucloxicillin

Question 37

Which bacterial species causes impetigo?

Answer 37

S. aureus

Question 38

Which toxins are associated with S. aureus and which disease does each cause?

Answer 38

1. Enterotoxin - food poisoning 2. SSST - Staphylococcal scalded skin syndrome 3. Panton valentine leukocidin - associated with MRSA

Question 39

Commensals of the bowel are usually _____ haemolytic

Answer 39

Commensals of the bowel are usually **non** haemolytic

Question 40

Which treatments are suitable for skin/nail involvement in dermatophyte infection?

Answer 40

1. Amorolfine (topical nail paint) 2. Clotrimazole (cream)

Question 41

Which treatments are suitable for scalp involvement in dermatophyte infection?

Answer 41

1. Oral terbinafine 2. Oral itraconazole

Question 42

What is the most common organism to cause tinea fungal infections?

Answer 42

Trichophyton rubrum (Trichophyton mentagraphytes, second most common)

Question 43

What is the classic appearance of a lesion induced by a tinea fungal infection?

Answer 43

Ring appearance (due to lesion growing outwards and healing in the centre)

Question 44

Which gender is more commonly affected by tinea fungal infections?

Answer 44

Males