皮膚アミロイドーシス

抄録

115 cases of lichen amyloidosus were found in a skin clinic in Taiwan during a pariod of 4 years. Lichen type occurred in 78 cases and 10 cases of macular type and 27 cases of biphasic type were seen. The great majority of the patients were middle-age males with a long duration of the disease over than 5 years. The extensive surfaces of the limbs were most commonly involved. Crystal violet staining is the most simple and reliable histochemical method to make a firm diagnosis. If the equipment available, fluorescent microscopic studies of thioflavin-T or Phorwhite BBU are useful for diagnosis. Immunoglobulin assay showed within normal limits in 12 cases of lichen amyloidosus. T and B cell ratio was normal in 8 cases but 15 out of 16 cases revealed positive immunofluorescence in either IgG, IgA, IgM or C3. Selectively, skin abrasion was carried out in 25 cases ; 6 cases had no reccurance after a three-year follow-up. Positive amyloid deposits were seen in the clinically normal looking skin about 10 cm from the lesion in 6 out of 12 cases with lichen amyloidosus. In secondary cutaneous amyloidoses, amyloid deposits could be seen in basal cell epithelioma, seborrheic keratosis, porokeratosis and Bowen's disease but in 20 leprosy patients, no amyloid was found in the skin biopsy materials.