Sudden unexpected death associated with lymphocytic thyroiditis.

A forensic autopsy study comprising 125 cases was carried out retrospectively in order to evaluate pathological changes in the thyroid gland in different groups of death. The five groups selected consecutively were: (i) opiate addicts who died from an overdose, (ii) alcoholics who died as a result of their alcohol abuse, (iii) cases of fatal poisoning other than opiate addicts, (iv) unknown cause of death and (v) controls without prior disease. Tissue samples from the thyroid gland were cut and stained with haematoxylin and eosin and van Gieson. Histology examinations were subsequently performed blind with semiquantitative assessment of the following six parameters: (a) height of the follicular epithelium, (b) the amount of lymphocytes, (c) the presence of plasma cells, (d) hyperplastic follicular changes, (e) oxyphilic changes, and (f) fibrosis. The most striking result was the finding of extensive lymphocytic infiltration of the thyroid parenchyma in five of the 124 cases, of which four belonged in the group of 'unknown cause of death'. This discovery leads to reflections regarding lymphocytic thyroiditis as a cause of death, either by itself or in combination with other disorders. Silent (painless) thyroiditis, especially, is easily overlooked at autopsy as there are no macroscopic changes and often no prior symptoms or history of thyroid disease pointing towards this condition. Analyses of thyroid hormones are unreliable in predicting endocrine status in life. Routine microscopy of the thyroid gland is therefore advocated in cases of sudden unexpected death in order to diagnose thyroid disease, in particular silent (painless) thyroiditis.