@article{7853,
  keywords = {Antigen-Antibody Complex, Cytokines, Erythema Nodosum, Humans, Immunity, Cellular, Leprosy, lepromatous, Risk Factors, Skin},
  author = {Kahawita I P and Lockwood DN},
  title = {Towards understanding the pathology of erythema nodosum leprosum.},
  abstract = {<p>Erythema nodosum leprosum (ENL) is an immune-mediated complication of leprosy presenting with inflammatory skin nodules and involvement of multiple organ systems, often running a protracted course. Immune complex production and deposition as well as complement activation have long been regarded as the principal aetiology of ENL. However, new data show that cell-mediated immunity is also important. We have performed a critical analysis of studies on the pathology of ENL. Our main findings are as follows. ENL is characterised by an inflammatory infiltrate of neutrophils with vasculitis and/or panniculitis. There is deposition of immune complexes and complement together with Mycobacterium leprae antigens in the skin. Changes in serum levels of Igs indicate a transient, localised immune response. The major T-cell subtype in ENL is the CD4 cell, in contrast to lepromatous leprosy where CD8 cells predominate. The cytokines TNFalpha and IL-6 are consistently found whilst IL-4 is low or absent in ENL lesions, indicating a T(H)1 type response. Keratinocyte 1a and intercellular adhesion molecule-1 (ICAM-1) have been shown to be present in the epidermis in ENL, which is evidence of a cell-mediated immune response. Co-stimulatory molecules such as B7-1 have also been studied but further work is needed to draw strong conclusions. We also highlight potential areas for future research.</p>},
  year = {2008},
  journal = {Transactions of the Royal Society of Tropical Medicine and Hygiene},
  volume = {102},
  pages = {329-37},
  month = {2008 Apr},
  issn = {0035-9203},
  doi = {10.1016/j.trstmh.2008.01.004},
  language = {eng},
}