MORPHOLOGY, IMMUNOHISTOCHEMISTRY AND MORPHOMETRY OF THE THYROID-GLANDIN CASES OF SUDDEN-INFANT-DEATH-SYNDROME (SIDS)

The thyroid glands of 107 SIDS victims (sudden infant death syndrome) have been studied. Controls consisted of 20 thyroid glands from infant s who died of other causes (accidents, pneumonia etc.). The thyroid gl ands were investigated histologically, immunohistologically and morpho metrically. Immunohistochemistry (S-100 protein and calcitonin) and mo rphometry showed no significant results. Histologically, hyperemia (se vere: 34 cases = 31.8%; mild: 23 cases = 21.5%), and fibrosis (45 case s = 42.1%; mild: 26 cases = 24.3%) were found. A large number of cases showed depleted follicles (87 cases = 81.3%), little colloid (little: 37 cases = 34.6%; none: 9 cases = 8.4%) and desquamation (severe: 21 cases 19.6%; abundant: 20 cases = 18.7%). Only fibrosis and depleted f ollicles were found more often in SIDS than in the controls (condition al logistic regression: rise of incidence for SIDS 2.9 times, P = 0.02 8, and 1.2 times, P = 0.051, respectively), a commoner occurrence of h yper emia in SIDS was of limited significance (P = 0.105). The alterat ions found can be taken as stress reactions to current or recurrent hy poxemia and the mild fibrosis indicates recurrent hypoxemia. All alter ations indicate that the victims had previously suffered near death ep isodes. Even though the glands were handled with care, artefacts and a utolysis must be taken into consideration. Neither the histological, i mmunohistological nor morphometrical studies of the thyroid gland gave an explanation as to the cause of death or showed any changes providi ng explicit help in diagnosing SIDS.