Abstract
In order to study the taste disturbance in diabetes mellitus, electrogustometry was carried out in 158 diabetics and compared with that in 1, 029 normal subjects. Taste abnormalities were noted in 26 % of the diabetic group. Comparison of these results with the knee jerk revealed a significantly more frequent taste abnormality in those with a decreased or absent knee jerk than in those with a normal reflex (p<0.01). In the case of precoma, a marked improvement in taste threshold was noted along with the improvement of blood sugar value. In order to study the relationship between taste abnormality and the disease picture of diabetes mellitus, changes of lingual papillae and lingual blood vessels were photographed, and angiography of the lingual blood vessels was attempted for a more detailed study. According to these results, the lingual papillae of diabetics are frequently flattened which is in agreement with the findings after disruption of the innervating chorda tympani. Such flattening of lingual papillae appears to be due to diabetic neuropathy, in view of the relationship of such findings to the abnormality in the electrogustometry. The blood vessels within the lingual papilla are distributed more coarsely than in normal subjects, with irregular loops, torsion and tortuosity of the blood vessels. Angiography revealed findings suggesting aneurysm. In order to study the diabetic microangiopathy in the tongue further, histological firidings were examined during autopsies. In the small blood vessels of the tongue, hyaline-like intimal thickening with PAS-positive substance was found, confirming the presence of microangiopathy in the tongue.
