Abnormal allometric size of vital body organs among sudden infant death syndrome victims

Sudden infant death syndrome (SIDS) victims are difficult to describe physically because they seem outwardly indistinguishable in nearly all characteristics from infants (alive or dead) of comparable chronological age. Relative (allometric) size of vital organ and body weights has not been examined among SIDS victims. In the present study, autopsy organ and body weights for 152 SIDS deaths (1-12 months) were compared with the results of 115 controls that were trauma or illness-related death (0.25-12 months). A pattern of abnormal relative size in vital organs (brain, heart, liver, and kidney) was revealed. In allometric regressions, increase in the weights of the organs relative to total body weight among SIDS victims were approximately three times the increase among controls in the first year of life. This finding indicates a disturbance of normal patterns of vital organ size of SIDS victims that is of unknown etiology.