Intrathoracic and subconjunctival petechiae in sudden infant death syndrome (SIDS).

The frequency and density of intrathoracic and subconjunctival petechiae was studied in 250 cases of SIDS and 69 controls. The control group included 37 infants with natural and 32 infants with traumatic causes of death. Intrathoracic petechiae were found significantly more frequently in the SIDS group (91.2% SIDS; 42% controls; p < 0.001) and were present at a higher density (p < 0.001). Subepicardial and thymic petechiae were detected at high density in older SIDS infants. Subconjunctival petechiae were low in density and found only in 2.4% of the SIDS group but they were detected in 8.1% of the natural death group and 21.9% (p < 0.05) of the lethal trauma group. Subconjunctival petechiae were found at highest density in strangulation. Intrathoracic petechiae are commonly found in SIDS but are not specific for SIDS. Subconjunctival petechiae are typical but not specific for strangulation. In SIDS, subconjunctival petechiae are rare and appear at low density.