Leprosy is a chronic infectious disease that requires better understanding since it
continues to be a significant health problem in many parts of the world. Leprosy
reactions are acute inflammatory episodes regarded as the central etiology of nerve
damage in the disease. The activation of endothelium is a relevant phenomenon to be
investigated in leprosy reactions. The present study evaluated the expression of
endothelial factors in skin lesions and serum samples of leprosy patients.
Immunohistochemical analysis of skin samples and serum measurements of VCAM-1, VEGF,
tissue factor and thrombomodulin were performed in 77 leprosy patients and 12
controls. We observed significant increase of VCAM-1 circulating levels in
non-reactional leprosy (p = 0.0009). The immunostaining of VEGF and tissue factor was
higher in endothelium of non-reactional leprosy (p = 0.02 for both) than healthy
controls. Patients with type 1 reaction presented increased thrombomodulin serum
levels, compared with non-reactional leprosy (p = 0.02). In type 2 reaction, no
significant modifications were observed for the endothelial factors investigated. The
anti-inflammatory and antimicrobial activities of the endotfhelial factors may play
key-roles in the pathogenesis of leprosy and should be enrolled in studies focusing
on alternative targets to improve the management of leprosy and its reactions.