Atypical ulcers: wound biopsy results from a university wound pathology service 

Chronic wounds are an increasing health burden across the continuum of care and encountered by a wide variety of healthcare providers and physicians of all specialties. The majority of chronic wounds are caused by vascular insufficiency, neuropathy, or prolonged pressure. Wounds caused by other underlying health conditions or external factors such as radiation or spider bites are usually referred to as atypical. Although a wound biopsy generally is recommended in the case of refractory, nonhealing ulcers or when wounds present with atypical signs and symptoms, little is known about the distribution of atypical ulcers. A retrospective, descriptive study was conducted to describe the proportion and differential diagnosis of atypical ulcer biopsies received during a 2-year period by the wound pathology division in the division of Dermatopathology at the University of Miami Department of Dermatology and Cutaneous Surgery. Of the 350 wound biopsies received for diagnostic purposes, 104 (29.7%) were due to atypical causes. The majority of specimens were neoplasms (n = 24). Pyoderma gangrenosum was the most common atypical diagnosis encountered (n = 14). Vasculitis, predominantly leukocytoclastic vasculitis, and external causes were diagnosed in 16 and 15 biopsies, respectively. This study represents the first published case series of atypical ulcer biopsy results from a wound pathology division. Although the prevalence results cannot be generalized and are likely lower in the general population of patients with nonhealing wounds, the results confirm the usefulness of obtaining wound biopsies to provide a definitive diagnosis and to guide care.