The New South Wales Pharmacy Trial for herpes zoster: on the nose?

To the Editor: Pharmacist prescribing initiatives in Australia are experiencing unprecedented popularity among state law makers, while community concerns regarding access to affordable general practice are increasing. Following the statewide roll‐out of pharmacist prescribing for uncomplicated urinary tract infections among female patients aged 18–65 years, the New South Wales Pharmacy Trial continues to expand.1 From 19 July 2024, participating pharmacists are authorised to assess and treat adults with common dermatological conditions, including herpes zoster (shingles), atopic dermatitis, impetigo, and plaque psoriasis, after undertaking a series of training modules.2 The trial closes in February 2025, or when the maximum number of trial‐supported consultations has been reached.2 A similar 12‐month pilot is currently underway in Victoria.3

Although protocolised health care can prevent deviations from evidence‐based care, robust clinical standards are required. The NSW trial's clinical practice guidelines for herpes zoster appropriately identify indications for immediate referral to a general practitioner or emergency department in the presence of complications, including postherpetic neuralgia, herpes zoster ophthalmicus, herpes zoster meningoencephalitis, and herpes zoster oticus (Ramsay Hunt syndrome). Despite correctly noting that “vesicles on the nose have been found to be predictive of eye involvement,” the guidelines erroneously attribute these findings (Hutchinson sign) to herpes zoster oticus, not herpes zoster ophthalmicus.4,5

Eponymously named for the English surgeon and ophthalmologist Sir Jonathan Hutchinson in 1864,6 Hutchinson sign denotes cutaneous involvement of the lateral dorsum, tip or root of the nose. Attributed to varicella zoster virus reactivation within the infratrochlear and external nasal nerves, terminal divisions of the nasociliary nerve and ophthalmic nerve, Hutchinson sign strongly suggests a diagnosis of herpes zoster ophthalmicus.7 It is a powerful predictor of varicella zoster virus keratitis, uveitis, and corneal denervation,8 and is often taken by general practitioners as an indication for prompt ophthalmic referral.9 In contrast, Ramsay Hunt syndrome is characterised by viral re‐activation within the geniculate ganglion and is associated with ipsilateral otalgia, hearing loss, peripheral facial nerve palsy, and herpetiform rash within the external auditory canal, pinna, and oral mucosa.10 The current clinical practice guidelines risk misdiagnosis between two anatomically distinct entities, with potential consequences, including inappropriate patient referral and delayed treatment initiation, which would not serve to allay community concerns regarding pharmacist prescribing in NSW. This concern was communicated to trial investigators for further review on 25 September 2024.