Decreased salivary gland function in patients with autoimmune thyroiditis.
OBJECTIVE
It has been speculated that impaired salivary flow contributes to autoimmune thyroiditis (chronic thyroiditis, Hashimoto's thyroiditis). To test this hypothesis, salivary function was measured by quantitative salivary scintigraphy in autoimmune thyroiditis patients, as well as in age- and gender-matched controls for comparison.


METHODS
One hundred and twenty patients with an autoimmune thyroiditis history of more than 10 years each and 36 healthy controls were enrolled in the study. All the 120 autoimmune thyroiditis patients had good blood sugar control. None had autonomic neuropathy. These 120 autoimmune thyroiditis patients were separated into two subgroups: group 1, 60 patients with xerostomia; and group 2, 60 patients without xerostomia. After intravenous injection of 5 mCi Tc-99m pertechnetate, sequential images at 1 min/frame were acquired for 30 min. The first- and 15th-minute uptake ratios (UR) were calculated from the tracer uptakes in the four major salivary glands over the background regions of interest (ROIs). Saliva excretion was stimulated by 1 tablet of 200 mg ascorbic acid given orally 15 min after injection of the tracer. Then, the maximal excretion ratios (ER) of the four major salivary glands after sialagogue stimulation were calculated.


RESULTS
Impaired salivary function, represented by significantly decreased UR and ER values, in autoimmune thyroiditis patients with xerostomia was demonstrated in this study. In addition, there was a significantly higher prevalence of salivary gland dysfunction in group 1 patients than in group 2 patients.


CONCLUSIONS
Significantly poorer salivary function was found in autoimmune thyroiditis patients with xerostomia compared with autoimmune thyroiditis patients without xerostomia and healthy controls by means of objective and quantitative salivary scintigraphy.
Chang
Cheng-Pei
CP
Division of Allergy, Immunology, and Rheumatology, Changhua Christian Hospital and China Medical College Hospital, Changhua, Taiwan.
Shiau
Yu-Chien
YC
Wang
Jhi-Joung
JJ
Ho
Shung-Tai
ST
Kao
Chia-Hung
CH
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012463:Saliva / Q000378:metabolism; D012469:Salivary Glands / Q000000981:diagnostic imaging*; D012636:Secretory Rate; D013670:Sodium Pertechnetate Tc 99m; D011795:Surveys and Questionnaires; D013967:Thyroiditis, Autoimmune / Q000150:complications* / Q000000981:diagnostic imaging; D013997:Time Factors; D014987:Xerostomia / Q000209:etiology*
D019275:Radiopharmaceuticals; D013670:Sodium Pertechnetate Tc 99m