8/11/2019 Chicken Pox Guidelines

1/1

NUH Guide to the Clinical Management of Chicken Pox in Adults

Adapted from the BIS draft algorithm published March 2007 www.britishinfectionsociety.org

Box 1

Y

Patient unwell, with newchicken pox vesicles

within last 24-48 hrs?N

Symptomatic treatment only, monitorfor signs of severe infection (Box 2)

Pregnant? Y

N

Signs of severeinfection? (Box 2)

Give oral Aciclovir800mg x 5/day for 7days (Box 3) andmonitor for signs ofsevere infection

Signs of severe infection? (Box 2)

Other risk factors for pneumonitis?- smoker, chronic lung disease?

N

Y

N

Admitto isolation bed in hospital forregular monitoring by staff known to beimmune (inform Infection Control)

Consider IV Aciclovir (10mg/kg tds)

Check LFTs, renal function and clottingfor DIC

Review CXR for evidence ofpneumonitis, monitor pO2

I f temp fails to settle consider possible2

oStaph. aureus infection

Switch to oral therapy as soon as

possible

Immunocompromised?

Current chemo-/radiotherapy, orwithin last 6/12 (12/12 for Bonemarrow transplant)

Steroids (>5mg/day) within last3/12

On Azathioprine or Methotrexate Box 3

Y

Y

N

Give oral treatment (Box 3) +symptomatic relief

Advise re infection risk (Box 1)Monitor for severe infection (Box 2)

Y

Oral Treatment:

Valaciclovir 1g tds 7 days

or Aciclovir 800mg x5/day

(NB: bioavailability of oral Aciclovir is poor)

Intravenous treatment:Aciclovir 10mg/kg tds

Renal impairment:dose reduction required forall forms of Aciclovir

5

Pregnancy:No adverse data for use ofAciclovir, data inadequate for Valaciclovir

5

Chicken pox is the primary systemic infection with Varicella-Zoster virus (VZV)

Acute systemic VZV has increased mortality and morbidity in adolescents and adults compared tochildren

1. Immunocompromised adults and non-immune pregnant women are at particular risk

2

Prompt treatment with Aciclovir reduces duration and severity o f symptoms3

There is no evidence of benefit of Aciclovir once the rash has been established for >48hrs

3

Infectivity: 2/7 prior to onset rash, until all vesicles crusted. Immunity in contacts can be assumedif clear history of clinical chicken pox

Incubation of chicken pox: 8-21 days

References:1. United Kingdom Advisory Group on Chickenpox. Consensus guidelines for management of varicella-zoster infection. J. Infection 1998; 36 Suppl 1: 1-83

2. Scientific Advisory Committee of Royal College of Obstetricians and Gynaecologists. Guidelines onchickenpox in pregnancy. 2001; Guideline No. 13: 1-83. Wallace MR, Bowler WA, Murray NB, Brodine SK, O ldfield EC3rd Treatment of adult varicella withoral aciclovir. A randomised, placebo-controlled trial.

Ann Intern Med. 1992 Sep 1:117(5): 358-634. Miller E, Marshall R, Vurdien J. Epidemiology, outcome and control of varicella-zoster infection.Reviews in Med Micro 1993; 4: 222-305. Joint Formulary Committee. British National Formulary. 52 ed. London: British Medical Associationand Royal Pharmaceutical Society of Great Britain; Sept 06

Box 2

Signs of severe infection include:

Resp iratory symptoms(clinical resp signs often absent)

Densely cropping vesicles

Haemorrhagic rash

Bleeding

Any neurological changesPersisting fever with new vesicles

>6 days after onset