An 84 year-old man presented to hospital one day after the sudden onset of a severe, right-sided headache. He was on warfarin therapy following mitral valve replacement. The sharp, stabbing pain had worsened overnight. He was admitted to the neurosurgery service, but no acute intracranial process was evident on computed tomography and arteriography. Subsequent evaluation by ophthalmology ruled out temporal arteritis and glaucoma. He was started on carbamazepine for a presumed diagnosis of trigeminal neuralgia. When his symptoms failed to improve, he was transferred to the Medicine Service on hospital day 3. He described constant pain and allodynia in an area encompassing his right orbit, temple, and periauricular scalp. He denied vision changes or neurologic deficits.
On examination, his right eye demonstrated tearing and ptosis. Pupils, sclera, extra-ocular movements, and visual acuity were normal. There was no tenderness to the sinuses, scalp, or auricle. Neurological exam was otherwise unremarkable.
Pertinent workup conducted through hospital day 3 included a leukocyte count of 6.4 x103/mm3, an erythrocyte sedimentation rate of 37 mm/hr, and a high-sensitive C-reactive protein of 0.3 mg/liter.
On hospital day 4, chemosis and injection of the right eye were noted. Several hours later, the beginnings of a vesicular rash appeared over the superior portions of his right face, scalp and nose. A tzanck smear was positive.
While headaches are a common reason for patients to seek medical care, the presentation of new headache in an older adult should raise particular concern. Up to 15% of new headaches in patients over age 65 are caused by serious, often life-threatening conditions. Particularly ominous is the presentation of sentinel or “thunderclap” headache. By definition, sentinel headaches reach peak intensity within one minute of onset. Patients classically describe them as “the worst headache of my life”. Vascular insults are the most concerning diagnoses to consider, including stroke, venous sinus thrombosis, or subarachnoid hemorrhage, and may be identified with CT imaging.
Herpes zoster ophthalmicus (HZO) has not typically been associated with sentinel headache, but the sharp, stabbing pains it causes may mimic this presentation. Herpes Zoster refers to reactivation of the varicella virus within the dorsal root ganglia of the nervous system due to impaired cellular immunity. In HZO, reactivation takes place within the ophthalmic branch of CN-V, producing sharp-stabbing pains and paresthesias within a distribution encompassing the nose, orbit, and scalp. Symptoms may be present for days prior to the appearance of the classic erythematous vesicular rash.
HZO requires emergent ophthalmologic evaluation to rule out direct ocular involvement, which occurs in 50% of cases and may result in blindness. Prompt initiation of acyclovir within 72 hours of rash is the mainstay of treatment, effective in reducing pain, some ocular complications, and post-herpetic neuralgia. First-line agents for symptomatic control include tricyclic antidepressants and/or gaba-receptor agonists.
Sentinel headaches in the older population are often due to vascular insult and deserve thorough evaluation. If negative, history and physical exam findings may guide hospitalists to alternative causes of headache such as the neuropathic pain associated with herpes zoster.
To cite this abstract:Butterfield M, Grundy I. The Worst Herpes of My Life: Zoster Ophthalmicus Presenting As Sentinel Headache. Abstract published at Hospital Medicine 2015, March 29-April 1, National Harbor, Md. Abstract 467. Journal of Hospital Medicine. 2015; 10 (suppl 2). https://www.shmabstracts.com/abstract/the-worst-herpes-of-my-life-zoster-ophthalmicus-presenting-as-sentinel-headache/. Accessed April 2, 2020.