• NZ has high rate of serious skin infections: children esp.

• Maori/PI

  • 2.3-3.7x more likely

• Chidlren low SES

• Preschoolers

• Boys

• Children from urban/upper half of NI

• Staph and Strep

  • Strep progenies skin -> inc. risk of RF

• no clear evidence that antiseptics are effective or not effective

-

Impetigo:

• Highly infectious

  • s.aureus

    • bullous

      • torso more likely affected

      • do not lance

    • non bullous

  • s.pyogenes

  • nullous

• children but can affect anyone

• warm/humid conditions or poor hygiene

• Topical abx 7/7

  • fusidic acid as effective as oral abx for small localised patches

• oral fluclox for 7/7 if extensive

• nasal swab and intranasal abx

• Avoid school/preschool for 24hours after initiation of treatment

• use separate towels/linen and reg. hand washing

• cover affected area where possible

Boils and abscesses:

• S.aureus

• most can be I&D alone

• oral fluclox for 7-10/7 if fever, cellulitis, co-morbid

• consider decolonisation

Cellulitis:

• S.aureus

• S.pyogenes

• all layers of skin, fascia and muscle may be involved

• limbs most commonly involved

• complciations:

  • endocarditis

  • gram negative sepsis

  • streptococcal glomerulonephritis

• more common:

  • previous cellulitis

  • venous disease

  • current/prior injury

  • alcoholism

  • obesity

  • pregnnacy

  • tinea pedis

• fluclox 7-10/7

• Referral for IV Abx

  • children \<1yr

  • cellulitis: periorbital or orbital

  • surrounds a limb

  • located over joint

  • fails to respond to oral abx

• analgesia and elevation

Infected eczema

• S.aureus

• infection suggested by lesions that are crusted, weeping or failing to respond to treatment

• topical abc may be suff. if localised

• oral fluclox if extensive areas

Management principles

• Hand washing

• Manage skin condition: eczema

  • affect 15% maori and 16% pacific

• Promote healthy lifestyle

Decolonisation:

• Nasal decolonisation: fusidic acid bd for 5/7

• Topical body decolonisation with dilute bleach baths, or triclosan 1% solution applied as a whole body wash daily for 1 /52 repeated if required

• Bleach baths:

  • 2-3 times/week

  • Quater/half cup unscented household bleach (sodium hypochlorite 6%) added to bath water

  • stay in bath 5-10 minutes then rinse off with fresh water

  • children should be supervised

  • if med/emollients required apply after skin has been patted dry

  • should not be used if extensive areas of broken skin

Seminar information and Regime

• test in nasal cavity (or axilla/groin)

• Regime: 50% success

  • Fusidic acid 1 four times /day for 1 week

  • chlorhexidine shower - 1/day for 1 /52

• Pulse:

  • 1/52 per month for 3 months

• Flucloxacillin not good at intranasal (intracellular)

• Cotrimoxazole or Rifampicin

• Treat family

wounds

any injury that damages the skin compromising protective function

chronic: failed to heal within 3 months

Healing

• wounds heal by primary closure

• secondary closure:

  • contracture and epithelialisation

• delay in healing number of factors:

  • local

    • underlying cause/severity

    • delay in presentation

    • necrotic tissue in the wound

      • can promote growth of bacteria

    • foreign bodies

    • impairment of local circulation

    • site of wound

    • haematoma - ‘dead space’ in wound

    • oedema

    • continued trauma/pressure to wound site

  • systemic

    • predisposing medical condition

    • older age

    • obesity

    • smoking

    • poor nutrition

    • immunosuppression

• factors that delay also increase likely hood of infection

Colonisation vs infection

• all open skin wounds are colonised by bacteria

• inflammation occurs in all wounds during healing regardless of infectin

  • certain level of swelling, erythema, iincreasewarmth == normal

• bacteria from 3 main sources:

  • environment

  • surrounding skin

  • mucous membranes

• infection:

• 1. contamination - non-replicating bacteria enter wound

  2. colonisation - bacteria replicating and adhere to wound site: do not cause tissue damage. not delayed by colonisation and can enhance healing process

  3. Local infection or critical colonisation - number of bacteria greatly increased and begins to overwhelm host immune system

     1. granulation bed in wound appears unhealthy

        1. atrophied, deep red, grey

     2. increased discharge

     3. no sign of invasion of surrounding tissues

     4. delayed healing may be only clinical sign

  4. Spreading invasive infection

     1. erythemat

     2. pain

     3. purulent discharge

  5. septicamia

Red flags:

• Rapidly developing tissue necrosis or gangrene

• extensive cellulllitis:

  • or cellulitis of:

    • face

    • hands

    • joints

    • periorbital area

• systemic illness without another obvious cause

• clinical signs suggesitve of osteomyelitis

  • deep bone pain

  • fever

  • chills

• pain unrelieved by simple analgiesics

• non-healing/worsening wound in diabetic

• suspected malignancy

• lower threshold for referral in those with comorbidiites or psychosocial factors

Biofilms

• several factors determine: contamination -> infection

  • bacterial load

  • type of bacteria

  • synergistic action

  • virulence

• communities of bacteria

  • embedded in an extraceullular polysaccharide matrix

• bacteria within biofilm physically protected from host environment and can communicate with each other (quorum sensing)

• change phenotype

  • increase virulence

  • increase likelihood causing infection

• biofilm becomes impediment to healing of chronic wounds

• 50-1000times more resistant to conventional antimicrobial treatment

• physically removed through debridement

When/how should wound be swabbed

• determin antibiotic choice and predicting response

• only useful in context of infected wound

  • therefore only swabbed if cilnical signs of infection:

    • and wound deteriorating

    • increase in dize

    • failing to heal

• classical sign of infection:

  • new/increase pain

  • swelling

  • erythema

  • purulent exudate

  • malodour

  • localised warmth around site

• in DM classical signs may not be always obvious -> lower threshold

• chronic wound signs:

  • discolouration of granulation tissue

  • ‘foamy’ granulation tissue

  • contact bleeding

  • tissue breakdown

  • epithelial bridging

    • incomplete epithelialisation

• if wound not purulent:

  • cleaned prior to swabbing

    • sterile saline

    • superficially debrided with cotton swab

• sterile saline to moisten head of swab

• pass swab over woudn in zigzag motion while twisting

• swab from centre -> edge

• presesed firmly enough that fluid expressed from wound tissue

• repeat process with separate swab if pocket/sinus present

• ideally processed wihtin 48hours

  1. stored at room temperature if same-day processing

emperic antibiotics

• acute wounds where risk of infection and compliations high

flora of wounds

• 1/4 s.aureus

• superficial burns;

  • do not usually become infected

  • unless other systemic factors present

  • s.aureus and other g+

  • later, g-: pseudomona, coliforms

• bite wounds

  • more exotic flora

  • polymicrobial

    • staph spp

    • peptostreptococcus

    • bacteroides

• surgical wounds

  • clean surgery

• Diabetic foot infections

  • s.aureus

  • s.epidermidis

  • sterp spp

  • pseudomonas

  • entercoccus

Topcial antibacterials - mupirocin(bactroban)

• remains active against MRSA

• reserved only for use when MRSA present

if wound doesn’t resolve:

• 48-72 hours:

  • take swab

• is it malignant?

  • can degenerate into malignancy - vice versa

  • chronic wound - Marjolin’s ulcer

    • 2% undergo malignant transformation

    • usually present >6/12

    • SCC

    • excessive granulation extends beyond wound margin

    • irregular base/margins

    • change in discharge/bleeding/outward(exophytic) growth