Value of the serum thyroglobulin level for diagnosing neck compression in postmortem cases

To investigate the relationship between blood thyroglobulin (Tg) levels and neck compression, the Tg levels of right cardiac blood were measured using a chemiluminescence immunoassay in 256 autopsy cases. There were 11 cases in which neck compression was confirmed based on autopsy findings and other information, in which the mean Tg level was 3155 ng/mL (range: 179-16,500 ng/mL). In the remaining cases, the mean Tg level was 4160 ng/mL (range: 0.3-139,000 ng/mL). There was no significant difference between the mean Tg levels of the two groups. In a comparison between the case groups with Tg levels of ≥200 ng/mL and <200 ng/mL, it was found that the frequency of neck compression was significantly higher (P < 0.05) in the ≥200 ng/mL group. The frequency of high Tg levels (≥200 ng/mL) was increased among the cases in which death was caused by neck compression or asphyxia. In a comparison of the median Tg values of right heart blood, left heart blood, whole blood, and femoral venous blood, the median Tg values of whole blood and right heart blood were shown to be about 10 times higher than those of left heart blood and peripheral blood. It is said that high postmortem blood Tg levels are caused by mechanical compression of the thyroid gland. However, high Tg levels were detected in the half of the cases without neck compression. Therefore, neck compression should be diagnosed carefully based on autopsy findings and other information.