Skin and soft tissue Infections

Question 1

What makes up the normal flora of the skin?

Answer 1

Coagulase-negative staphylococci

Staph aureus

Question 2

What are the signs and symptoms of herpes simplex generally?

Answer 2

cold sores - come and go by triggers e.g. infection/stress

tingling

Question 3

What are the two stages of herpes simplex? What are their features?

Answer 3

Primary: occurs once, rara, extensive, painful lesions, inside mouth
Secondary: Happens more than once, Peri-oral, weeping, vesicular

Question 4

How is herpes simplex diagnosed?

Answer 4

Clinical

Vesicle fluid - PCR

Question 5

What is the treatment for cold sores? (How it is given is important here?

Answer 5

Topical acyclovir

Question 6

What is the treatment for genital herpes? (How it is given is important here?

Answer 6

Oral acyclovir

Question 7

What is the primary and secondary manifestation of varicella zoster virus?

Answer 7

Primary: chickenpox
Secondary: shingles

Question 8

What is latent varicella zoster virus triggered by?

Answer 8

Physical/emotional insult

Tingling/pain

Question 9

How does varicella zoster virus present?

Answer 9

Weeping vesicular rash

Dermatomal distribution - diagnostic

Question 10

How is varicella zoster virus diagnosed?

Answer 10

Clinical

Vesicle fluid - PCR

Question 11

What is the treatment for varicella zoster virus?

Answer 11

Oral/IV acyclovir - depending on severity

Question 12

What does Molluscum contagiosum virus look like?

Answer 12

Raised, pearly lesions

Umbilicated - central depression

Question 13

How is Molluscum contagiosum diagnoised?

Answer 13

Clinically

Question 14

What is the treatment for Molluscum contagiosum?

Answer 14

None - disappears itself

Question 15

Name 6 bacterial infections of the skin

Answer 15

Impetigo
Erysipelas
Cellulitis
Necrotising fasciitis
Gas gangrene 
Anthrax

Question 16

Impetigo is infection of which layer of the skin?

Answer 16

Epidermis

Question 17

What pathogen normally causes impetigo?

Answer 17

S.aureus
S.pyogenes
Both

Question 18

What does impetigo present as?

Answer 18

Plaque like lesions
Yellowish exudate
Thick scabs - ‘honey crusted’

Question 19

How is impetigo diagnosed?

Answer 19

Clinically

Bacterial cultures - useful for sensitivity testing

Question 20

Erysipelas is infection of which layer of the skin?

Answer 20

Dermis

Question 21

What pathogen normally causes erysipelas?

Answer 21

S.pyogenes

Question 22

How does erysipelas present?

Answer 22

Pain
Tenderness
Fever/malaise
Well demarcated inflammatory lesion - red, swollen, hot
Lymph node enlargement

Question 23

How is erysipelas diagnosed?

Answer 23

Clinical diagnosis

Question 24

Cellulitis is infection of which layer of the skin?

Answer 24

Skin and subcutaneous tissue

Question 25

What pathogen normally causes cellulitis?

Answer 25

S.aureus | S.pyogenes

Question 26

How does cellulitis present?

Answer 26

Fever/malaise Diffuse inflamed lesion - Erythema, swelling, tenderness, heat Margins unclear

Question 27

How is cellulitis diagnosed?

Answer 27

Clinically Lesion swabs if possible Not cellulitis if bilateral!

Question 28

Anthrax is caused by which pathogen?

Answer 28

Bacillus anthracis

Question 29

Where is anthrax acquired from?

Answer 29

Imported wool, hair and animal hinds

Question 30

Necrotising fasciitis is infection of which layers of the skin?

Answer 30

Skin and subcutaneous tissues

Question 31

What two types of factors cause necrotizing fasciitis?

Answer 31

Type 1: Polymicrobial - enteric gram -ve bacilli, anaerobes | Type 2: Streptococcus pyogenes

Question 32

How does necrotizing fasciitis present?

Answer 32

``` Fever/malaise Dark Rapidly spreading Necrotising lesion Blisters ```

Question 33

How is necrotizing fasciitis diagnoised?

Answer 33

Microscopy and culture of: Debraided material Blood

Question 34

What is the treatment for necrotizing fasciitis?

Answer 34

IV antibiotics | Surgical debridement - removal of dead tissue

Question 35

What type of pathogen causes gas gangrene?

Answer 35

anaerobic bacteria

Question 36

How does gas gangrene present?

Answer 36

Same as necrotizing fasciitis | Feels soft/squishy like there is gas inside

Question 37

When does gas gangrene tend to occur?

Answer 37

Areas of poor blood supply | i.e. amputees that have PVD

Question 38

How is gas gangrene treated?

Answer 38

IV antibiotics | Surgical debridement

Question 39

What is the empirical therapy used for infections caused my staph aureus or strep pyogenes?

Answer 39

Flucloxicillin

Question 40

What is the empirical therapy used for necrotizing fascitis?

Answer 40

Meropenem | Clindamycin

Question 41

What fungi causes dermatophyte infections?

Answer 41

Tricophyton spp | Microsprum spp

Question 42

Name 3 dermatophyte skin infections

Answer 42

Tinea corporis Tinea pedis (athlets foot) Tinea cruris

Question 43

Name a dermatophyte nail infection

Answer 43

Onychomycosis

Question 44

Name a dermatophyte scalp infection

Answer 44

Tinea capitis (scalp ringworm)

Question 45

How are dermatophyte infection diagnosed?

Answer 45

Skin scrapings | Microscopy and culture

Question 46

What are the topical antifungal treatments used for dermatophyte skin infection?

Answer 46

Clotrimazole | Terbinafine

Question 47

What are the oral antifungal treatments used for dermatophyte scalp and nail infection?

Answer 47

Terbinafine | Itraconozole

Question 48

What antibiotics are used to treat impetigo?

Answer 48

Fusidic acid | Mupirocin