Skin and soft tissue infections

Question 1

Layers

Answer 1

epidermis
dermis
subcut fat
fascia 
muscle

Question 2

Risks

Answer 2

diabetes
immunosuppression
renal failure
Milroy's disease- lymphedema in legs
predisposing skin conitions eg atopic dermatitis

Question 3

Impetigo

Answer 3

gold crusty lesions
staph A common strep pyogenes less common
kids 2-5 yrs
highly infectious
face, extremities, scalp

Question 4

Impetigo treatment

Answer 4

topical antibs small areas

large need topical and oral antibs

Question 5

Erysipelas

Answer 5

inf upper dermis
painful red area
fever
lymphademopathy and lymphangitis
distinct elevated borders
strep pyogenes
lower limbs most common and some face

Question 6

Erysipelas treatment

Answer 6

oral or IM penicillin
5 days
cephalosporin if penicillin allergy

Question 7

Cellulitis

Answer 7

deep dermis and subcut fat
spreading erythematous area w no distinct borders
strep pyogenes and staph a
fever
lympahdenopathy and lympangitis

Question 8

Cellulitis risk

Answer 8

diabetes
tinea pedis
lymphoema

Question 9

Cellulitis treat

Answer 9

anti-staph and anti-strep antibs
dicloxacillin
amoxicillin
cephalezin

Question 10

Folliculitis

Answer 10

circumscribed, pustular infection of hair follicle
small red paupules
head, back, buttocks and extremities
staph a

Question 11

Furunculosis

Answer 11

furuncles commonly referred as boils
single hair collice assoc inflam nodules
dermis and subcut tissues
face, axilla, neck, buttocks
staph a
risks w obestiy, DM, CKD, corticosteroids

Question 12

Carbuncle

Answer 12

when infection extends to invulve multople furuncles
back neck, posteror trunk or thigh
multi septated absecess

Question 13

Furunculosis treat

Answer 13

hot copress
hot bath
no antibs unless not improving give oral

Question 14

Carbuncle treat

Answer 14

admission to hosp
surgery
IV antibs- rifampicin and clindamycin

Question 15

Necrotising fasciitis

Answer 15

emergency

risks- diabetes, surgery, trauma, vasuclar disease

Question 16

Necrotising fasciitis type 1

Answer 16

mixed aerobic and anaerobic infection
diabetes foot
fourniers gangrene
strep, staph,enterococci, gram neg bacili, clostridium

Question 17

Necrotising fasciitis type 2

Answer 17

monomicrobial
nromally strep pyogenes
rapid onset
erythema- oedema- pain
haemorrhagic bullae, skin necrosis 
fever, hypotension, tachy, delirium, multiorgan failure
need surgical review and anaethesia
broad spectrum antibs- flucclox,gent

Question 18

Pyomyositis

Answer 18

purulent infection deep within striated myscle, often manifesting abscess
secondary to seeding into damaged muscle
thigh, calf, arms, glutes, chest wall, psoas
fever, pain, woody induration affected muscle
commonly staph A
CT/MRI

Question 19

Pyomyositis risks

Answer 19

diabetes
HIV/immunosupp
IVDU
rheumatological disease
malignancy
liver cirrhosis

Question 20

Pyomyositis treat

Answer 20

drainage

antibs

Question 21

Septic bursitis

Answer 21

commonly patellar and olecranon
infection bursa
swelling red and warm
commonly staph a 
fever and pain on movement
diagnose by aspiration of fluid

Question 22

Septic bursitis risks

Answer 22

rheumatoid arthirits
alcoholism
diabetes
IVDU
immunosupp
renal insufficiency

Question 23

Infective tenosynovitis

Answer 23

infection of synovial sheets surrounding tendons
penetrating trauma commonly before
staph a or strep
erythematous fisiform swelling of finger
held in semi flexed position
tender over tendon sheet and pain w extension fingers

Question 24

Infective tenosynovitis treat

Answer 24

empiric antibs

hand surgeon review

Question 25

Toxin mediated syndromes

Answer 25

``` often due to superantigens group of pyrogenic exotoxins activate T cell pool themselves massive busrst cytokine release leads to endothelial leak, haemodynamic shock and multi orgam failure and deaths mostly staph A or strep pyogenes ```

Question 26

Toxic shock syndrome staph

Answer 26

fever hypotension diffuse macular rash involve other organs- liver, blood, renal, GI, CNS isolation of staph a from mucosal or nromally sterile sites

Question 27

Toxic shock syndrome strep

Answer 27

aoss w presence of strep in deep seated infections like necortising fasciitis mortality high urgent surgical debridement of infected tissues

Question 28

Toxic shock syndrome treatment

Answer 28

``` remove oddending agent eg tampon IV fluids inotropes antibs IV immunoglobulins ```

Question 29

Intravenous catheter associated infections

Answer 29

start w local inflam progressing to cellulitis and tissue necrosis associated bacteraemia (bacteria in blood) common staph A - MSSA and MRSA commonly forms biofilm which spills into bloodstream blood cultures

Question 30

Intravenous catheter associated infections management

Answer 30

remove cannula express pus from thrombophlebitis antibs 14 days echo

Question 31

Intravenous catheter associated infections prevention

Answer 31

``` dont leave unused cannula change every 72 hrs careful continuous infuse more than 24hrs monitor thrombophlebitis aseptic techniques ```

Question 32

Surgical site infections causes

Answer 32

``` staph a inclu MSSA and MRSA coagulase neg staph enterococcus e coli pseudomonas aeruginosa enterobacter strep fungi anaerobes ```

Question 33

Surgical site infections risk

Answer 33

``` diabetes smoking obese malnutrition steroid use colonisation shaving site improper preop skin prep break sterile technique inadequate theatre ventillation periop hypoxia ```

Question 34

Surgical site infections diagnosis

Answer 34

send pus/infected tissue for cultures avoid superficial swabs aim for deep structures consider an unlikely pathogen as a cause if obtained from sterile site

Question 35

Surgical site infections treat

Answer 35

antibs to target likely organisms