Parathyroids and Cervical Thymus in Sudden Unexpected Death in Infancy

Abstract

It has recently been claimed that there is a reduction in the number of parathyroid glands and abnormal fusion of parathyroid and thymic tissues in the sudden unexpected death (SUD) syndrome in infancy. In the present study, the parathyroid glands and thymus were dissected under the stereomicroscope at autopsy in 55 infants, including 31 with features of SUD. The identity of the glands was confirmed histologically. Parathyroid glands were identified in comparable numbers and sites in infants dying with the SUD syndrome or from some ascertainable cause. Cervical thymic tissue was commonly found in infants, whatever the cause of death, and fusion of parathyroid and thymic tissues was not confined to the SUD syndrome. The study provides no evidence to support the claim that there is a deficiency of parathyroid glands in the SUD syndrome or that fusion of thymic and parathyroid tissues normally does not occur.