Nontraumatic intradural and subdural hemorrhage and hypoxic ischemic encephalopathy in fetuses, infants, and children up to three years of age: analysis of two audits of 636 cases from two referral centers in the United Kingdom.

We analyzed the presence or absence of intradural hemorrhage (IDH) and subdural hemorrhage (SDH) and the degree of hypoxic-ischemic encephalopathy (HIE) in the brain of all nonmacerated fetuses of >24 weeks, neonates, and children up to 3 years of age who died of natural causes over a defined period. We looked into the cause of death and the performance of cardiopulmonary resuscitation in our cohort. The IDH was classified as macroscopic or negative/microscopic only; the HIE was classified as absent, indeterminate, or definite. In fetuses, SDH with IDH was present in 22%; IDH alone was present in 31%, and there was no or minimal hemorrhage in 47% of cases. In infants and children SDH with IDH was present in 19%; IDH alone was present in the 32%, and there was no or minimal hemorrhage in 49% of cases. There was a statistically significant correlation between SDH and HIE, especially in infants and children (P < 0.001). When cases were grouped per age, a significant association between age and hemorrhage (P < 0.0001) was demonstrated, SDH being more common in infants ≤1 month corrected age. Intradural hemorrhage can be the source of thin-film SDH in fetuses, infants, and young children. The presence of SDH is associated with hypoxia. Intradural and subdural hemorrhages are more common in autopsies of infants under 1 month corrected age. Although more rare, they can also be found in children between 1 month and 3 years of age in the absence of trauma.