Arai T, Kurashima C, Utsuyama M, Sawabe M, Ito H
Department of Pathology, Tokyo Metropolitan Geriatric Hospital, Japan.
Endocr J. 2000 Oct;47(5):575-82. doi: 10.1507/endocrj.47.575.
Subclinical thyroiditis or thyroid dysfunction is relatively common in the elderly. To estimate the effectiveness of measurement of serum levels of anti-thyroglobulin and anti-microsomal or thyroid peroxidase antibodies for detecting focal lymphocytic thyroiditis (FLT) in the elderly, we examined the relationships between antibody titer and postmortem histological finding of the thyroid gland in 180 consecutive autopsies (69 women and 111 men) over 60 years of age without any overt clinical thyroid or collagen diseases. FLT was found in 25 cases (13.9%) with female predominance (21.7% in female vs. 9.0% in male). Measurements of serum levels of anti-thyroglobulin and anti-thyroid peroxidase antibodies by radioimmunoassay (TgAb and TPOAb, respectively) were compared with the measurements of anti-thyroglobulin and anti-microsomal antibodies by a hemagglutination technique (TGHA and MCHA, respectively), using sera from 25 patients with FLT and age- and sex-matched 51 patients without FLT. Among 25 cases with FLT, TgAb and TPOAb were positive in 17 (68%) and 12 (48%), respectively. There was a close relationship between degree of FLT and serum level of TgAb or TPOAb (P<0.0001). On the other hand, TGHA and MCHA were positive only in 8 (32%) and 10 (40%), respectively. TgAb and TPOAb were more sensitive than TGHA (68% vs. 32%, P<0.05) and MCHA (48% vs. 40%) to detect FLT. Positive findings in either TgAb or TPOAb significantly improved sensitivity (76%) compared with that of TGHA or MCHA (44%) (P<0.05). Specificities of combined measurements of TgAb and TPOAb (90%) were not significantly different from those of TGHA and MCHA (100%). These findings indicate that TgAb is a more sensitive method for detecting FLT and that its diagnostic sensitivity for FLT increases by using it in combination with TPOAb. Therefore, in the elderly without clinically or biochemically overt thyroid dysfunction, positive TgAb and/or TPOAb could imply presence of FLT, and their titers might reflect degree of inflammation.
亚临床甲状腺炎或甲状腺功能障碍在老年人中较为常见。为评估检测血清抗甲状腺球蛋白和抗微粒体或甲状腺过氧化物酶抗体水平对检测老年人局灶性淋巴细胞性甲状腺炎（FLT）的有效性，我们研究了180例60岁以上无明显临床甲状腺疾病或胶原病的连续尸检病例（69名女性和111名男性）中抗体滴度与甲状腺尸检组织学结果之间的关系。在25例（13.9%）中发现了FLT，女性占优势（女性为21.7%，男性为9.0%）。采用放射免疫分析法（分别为TgAb和TPOAb）检测25例FLT患者以及年龄和性别匹配的51例无FLT患者血清中的抗甲状腺球蛋白和抗甲状腺过氧化物酶抗体水平，并与血凝技术（分别为TGHA和MCHA）检测的抗甲状腺球蛋白和抗微粒体抗体水平进行比较。在25例FLT病例中，TgAb和TPOAb分别有17例（68%）和12例（48%）呈阳性。FLT程度与TgAb或TPOAb血清水平之间存在密切关系（P<0.0001）。另一方面，TGHA和MCHA分别仅在8例（32%）和1０例（40%）中呈阳性。TgAb和TPOAb在检测FLT方面比TGHA（68%对32%，P<0.05）和MCHA（48%对40%）更敏感。与TGHA或MCHA（44%）相比，TgAb或TPOAb中的阳性结果显著提高了敏感性（76%）（P<0.05）。TgAb和TPOAb联合检测的特异性（90%）与TGHA和MCHA（100%）无显著差异。这些结果表明，TgAb是检测FLT更敏感的方法，并且将其与TPOAb联合使用可提高对FLT的诊断敏感性。因此，在无临床或生化明显甲状腺功能障碍的老年人中，TgAb和/或TPOAb阳性可能意味着存在FLT，其滴度可能反映炎症程度。
