What is the True Etiology of “Recurrent Shingles”?

Purpose: To determine the true etiology of cases of putative recurrent shingles referred to a dermatology clinic. Methods: A prospective cohort study of patients aged 15-87 years with reported recurrent herpes zoster was conducted. Vesicular fluid and serology for herpes simplex 1, 2, and varicella zoster virus immunoglobulins were obtained from patients presenting with vesicles. Biopsies were obtained from patients with ambiguous presentations. Results: 44 patients (56%) had evidence of herpes simplex virus infection. 32% of patients had positive herpes simplex virus cultures or polymerase chain reaction sequencing, and 24% additional patients were diagnosed with presumptive simplex infection based on elevated antibody titers. 44% of patients had a diagnosis other than zoster or simplex. One individual had a positive viral culture for varicella zoster virus. 99% of patients who presented with suspected recurrent herpes zoster had no definitive evidence of varicella zoster virus reactivation. Conclusions: The most common diagnosis was herpes simplex infection. Our results suggest that true recurrent shingles in immunocompetent patients is rare.