An elderly gentleman with advanced lung cancer managed in the intensive care unit for severe nosocomial pneumonia abruptly developed a rash over the right side of the chest. It was evidently pruritic.

Rash in an elderly gentleman with cancer.

Question: What is the clinical diagnosis?

[Updated 6th December 2014]

The patient had a vesicular rash (vesicular means small and sac-like) that was just over the right chest wall, also extending to his back. Not obvious from the photo, but the distribution of the lesions was dermatomal in nature. He had a reactivation of dormant varicella zoster virus (the virus that causes chicken pox), which is also known as zoster or shingles. The colloquial Chinese term for this is “snake”, owing to the dermatomal appearance of the rash. The main symptoms, other than the obvious rash, are itch and occasionally severe neuropathic pain. On very rare occasions, there may be other organ involvement (i.e. pneumonitis, encephalitis, or transverse myelitis), especially in patients that are severely immunocompromised.

Treatment is with acyclovir (useful within 48 hours of onset of zoster) as well as symptom relief with anti-pruritic medications and analgesics. There is currently a vaccine available, Zostavax, which is recommended for those above 60 years of age. Vaccine efficacy declines after 5 years, and may be less immunogenic in the very elderly or those who are markedly immunocompromised.