The pathology of the adrenal glands in sudden infant death syndrome (SIDS)

The sudden infant death syndrome (SIDS) is at present based on unknown pathogenetical mechanisms but in industrial nations is the most common cause of death in infancy after the perinatal period. Studies of a large number of adrenal glands in this syndrome have not been reported. Therefore, we evaluated 146 SIDS cases (85 males, 61 females, aged 14-465 days) and 24 control cases (17 males, 7 females, aged 18-623 days) by light microscopy, morphometry and immunocytochemistry (anti-chromogranin A and anti-S100 protein). Our data revealed a normal maturation of the adrenal glands in SIDS cases. Necroses, extensive hemorrhages or inflammation were not found. A focal lipid depletion of the zona fasciculata was seen in 92% of the adrenal glands of the SIDS and control cases. We found a siderosis (in 33% of the SIDS cases and 4% of the control cases) and calcium deposits (13% and 12% respectively) due to hyperemic involution of the fetal zone. The medulla, including the sustentacular cells (S 100 protein-positive cells) and chromaffin cells (chromogranin A-positive cells) was unchanged. Our results indicate that the few morphological alterations of the adrenal glands in SIDS cases are the effect of the underlying disease and not the cause of the sudden death.