[Role of adhesion molecules in tonsillar focal infection]

Pustulosis palmaris et plantaris (PPP) is a pustular skin disease that is closely related to tonsillar focal infection. Patients with this skin disease have shown marked improvements of skin lesions after tonsillectomy. In this study, we evaluated the role of adhesion molecules in the pathogenesis of tonsillarfocal infection related to PPP. The results were that tonsillar lymphocytes of patients with PPP adhered to vessels in the dermis, to vessels running through the dermal papilla, and to vessels in the epidermis at the base of pustules. The adhesion of tonsillar lymphocytes to endothelial cells were significantly blocked by anti-LFA-1 antibody. An immunohistological study revealed that cells infiltrating the dermis expressed LFA-1, whereas ICAM-1, the ligand of LFA-1, was detected on endothelial cells and keratinocytes. It is interesting to note that cells infiltrating the dermis of the erythema stage or the pustule stage of PPP expressed ICAM-1, and the vessels in these stages expressed E-selectin. ICAM-1 was also detected on vessels in the dermis of skin that seemed to be macroscopically normal. These results suggest that tonsillar lymphocytes may have an affinity for the skin of PPP-expressing adhesion molecules such as LFA-1, ICAM-1, and E-selectin. These adhesion molecules seem to be easily activated, not only in skin lesions of PPP, but also in macroscopically normal areas resulting in cellular infiltration and pustule formation.