Test your diagnostic skills in our regular dermatology quiz. What is this painful vesicular eruption on the arm of an elderly woman?
A 90-year-old woman is admitted to hospital with decompensated congestive cardiac failure and community acquired pneumonia requiring intravenous antibiotics and diuresis. During her admission, she develops a painful vesicular eruption on her arm where, 18 days previously, she was administered the live-attenuated varicella zoster virus (VZV) vaccine (Figure 1a). Aside from her age and a recent 10-day course of prednisone for podagra, she has no other cause for immunosuppression.