The severity of histopathological changes of leukocytoclastic vasculitis is not predictive of extracutaneous involvement

Leukocytoclastic vasculitis is defined by histologic features and can be observed in a wide range of entities. Independent of the causative disease, extracutaneous complications are frequent, mainly in the kidneys and gastrointestinal tract. It has been suggested that the severity of histological changes could correlate with the clinical course of the disease. We have therefore compared the severity of histological changes of leukocytoclastic vasculitis to clinical and laboratory findings indicative of extracutaneous involvement in a large group of patients. Among 289 patients followed for cutaneous vasculitis, we included 184 patients with purpuric papules and proven leukocytoclastic vasculitis who all had standardized investigations. A cutaneous biopsy was performed early and standardized laboratory investigations were carried out. The slides were retrospectively randomized and the depth of vasculitis and severity of vascular necrosis were determined according to a semiquantitative scale. These data were compared to the renal, gastrointestinal and articular symptoms using Fischer's exact test, Chi-square test and variance analysis. The intensity of vascular necrosis and the depth of vasculitis were no more severe in patients having renal changes, gastrointestinal involvement or articular symptoms. Both variance analysis and Chi-square tests failed to show a significant increase in the severity score in patients having extracutaneous complications. In this study, the severity of histopathological changes was not predictive of extracutaneous involvement. Thus it appears that the degree of involvement of the cutaneous vessels probably does not correlate with that of vessels in visceral organs.