Histopathologic vasculitis from the periulcer edge: A retrospective cohort study

Background Histopathologic vasculitis is often reported in periulcer specimens, but the frequency and clinical significance of this finding have not been evaluated. Objective We evaluated the sensitivity, specificity, negative predictive value, and positive predictive value of histopathologic vasculitis from the periulcer edge for detecting ulcers due to cutaneous vasculitis. Methods We performed a retrospective chart review of patients with leg ulcers at a tertiary hospital between 2009 and 2016. Histopathologic slides were evaluated by 2 dermatopathologists who were blinded to the etiology of ulcer. Focal vasculitis was defined as involvement of fewer than 3 vessels. Results Vasculitis at the periulcer edge was seen in 51.6% of the specimens (32 of 62). Of the specimens with histopathologic vasculitis, focal vasculitis was seen in the majority of specimens (71.9% [23 of 32]), whereas diffuse vasculitis was observed in 28.1% (9 of 32). Periulcer vasculitis yielded a high sensitivity (100% [95% confidence interval, 29%-100%]). Furthermore, the specificity was low (50.9% [95% confidence interval, 38.1%-63.6%]) for detecting vasculitis-induced ulcers. Limitations Small number of vasculitis-induced ulcers. Conclusion Focal vasculitis from the periulcer edge is a nonspecific finding and provides little diagnostic value in determining the etiology of lower leg ulcers. Emphasis should be placed on the combination of clinical history and examination, histology, and laboratory findings when diagnosing ulcers.