抄録
Information obtained from microscopic observation of the fungiform papillae of the tongue could be a sensitive and useful indicator of diabetic complications. To evaluate its clinical significance, the f ungif orm papillae of diabetics (n=33) were investigated under microscopy and histologically observed in 4 patients from whom informed consent was obtained. Fungiform papillae of the tongue were morphologically classified into 4 groups (I-IV) and the capillary vessels in the papillae into 5 groups (A-E). correlations between the morphological changes of the fungiform papillae and the disease period of diabetic complications were evaluated. Each type classified was tested for the clinical significance as an indicator of electric gustatory threshold abnormality. The results obtained were as follows;
1. In diabetics, the fungiform papillae were flattened, thickened and atrophic. The capillary vessels in the papillae were obscured or absent under microscopy.
2. The above changes appeared before the three major diabetic complications became clinically evident.
3. Elevation of the electric gustatory threshold was most sensitively reflected by an increase in type IV (remarkable flattening and atrophy of the papillae) and type E (disappearance of the vessels).
4. Histological observations of the fungiform papillae in diabetics showed flattening of the papillae, parakeratinization and thickening of the epithelium. Immunohistology of the capillary vessels revealed thickening of the type 1V collagen positive layer.
In conclusion, microscopic observation of the fungiform papillae is a sensitive and clinically useful examination for detection of diabetic microangiopathy and neuropathy.
