GP Quiz 8 - Case 1.
A 63-year-old woman presented with pain in the right buttock. Two days later she has developed erythematous plaques as illustrated. She is feeling mildly unwell. Close inspection reveals a few small vesicles.
What is the diagnosis?
She has Herpes zoster. The presentation of localised pain, malaise and rash is characteristic, but is surprisingly often misdiagnosed. There are small grouped vesicles on an inflamed base in a dermatomal distribution.
What investigations should be performed?
No investigations are necessary in most patients as the diagnosis is made clinically. In doubtful or unusual cases, herpes zoster can be confirmed by tissue culture of scrapings from a de-roofed blister.
What management should you recommend?
Treatment guidelines in the Pharmaceutical Schedule recommend oral aciclovir 800mg daily five times daily for seven days in the following circumstances:
- Ophthalmic zoster
- Immunocompromised patients
- If rash present for <3 days in patients over 50 with significant pain.
Valaciclovir and famciclovir are no longer available in New Zealand.
In addition, analgesics such as paracetamol, codeine phosphate, narcotics or amitripytline/nortripyline may be prescribed. Soothing antiseptic topical applications may be helpful.
The use of systemic corticosteroids is controversial and is not currently recommended.
This quiz was also published by ADIS International in in June 2000.