ASHEVILLE, N.C. – The incidence of leukocytoclastic vasculitis in the general population is 1.5 to 3 times higher than previously reported, based on data from a large, population-based study.
Based on these findings, leukocytoclastic vasculitis (LCV) is “more common than cutaneous lupus,” said Dr. David A. Wetter of the Mayo Clinic, Rochester, Minn.
Dr. Wetter and his associates reviewed data from all residents of Olmstead County, Minn., with a biopsy-proven diagnosis of LCV from January 1, 1996, through December 31, 2010.
A total of 84 patients were identified, for an overall incidence of 4.5 per 100,000 person-years. The mean age was 48 years, and approximately half were women.
The researchers divided the patients into five subtypes: cutaneous small vessel vasculitis (CSVV), IgA vasculitis, urticarial vasculitis, cryoglobulinemic vasculitis, and antineutrophil cytoplasmic antibody–associated vasculitis.
Systemic involvement occurred in 46% of the patients, with the kidneys involved in 44% of these cases. Recurrent disease was observed in 30% of the 80 patients for whom follow-up data were available.
In addition, LCV was idiopathic in 76% of CSVV patients, significantly higher than the 45% rate reported in the current textbooks, Dr. Wetter noted. Idiopathic LCV also occurred in 96% of patients with IgA vasculitis.
Overall survival was significantly decreased in the LCV patients compared to the general Minnesota population, but the reasons for this difference remain unclear and are worthy of additional study, Dr. Wetter noted. However, survival was not significantly decreased in the subset of patients with IgA vasculitis, despite the high rate of systemic involvement, he added.
Although the study was limited by its retrospective nature and relatively homogeneous white population, it is the first known population-based study of histopathologically-defined LCV, and the data support the evaluation of all patients with LCV “for extracutaneous disease and systemic etiologies for their disease,” Dr. Wetter said.
Dr. Wetter presented the study findings at the annual meeting of the Noah Worcester Dermatological Society. The data also were published in the Mayo Clinic Proceedings in 2014 (Mayo Clin. Proc. 2014;89:1515-24).
Dr. Wetter had no financial conflicts to disclose.