Identifying Genetic Susceptibility in Neonates With Hypoxic-Ischemic Encephalopathy: A Retrospective Case Series.

Neonatal hypoxic-ischemic encephalopathy is a clinical phenomenon that often results from perinatal asphyxia. To mitigate secondary neurologic injury, prompt initial assessment and diagnosis is needed to identify patients eligible for therapeutic hypothermia. However, occasionally neonates present with a clinical picture of hypoxic-ischemic encephalopathy without significant risk factors for perinatal asphyxia. We hypothesized that in patients with genetic abnormalities, the clinical manifestation of those abnormalities may overlap with hypoxic-ischemic encephalopathy criteria, potentially contributing to a causal misattribution. We reviewed 210 charts of infants meeting local protocol criteria for moderate to severe hypoxic-ischemic encephalopathy in neonatal intensive care units in Calgary, Alberta. All patients that met criteria for therapeutic hypothermia were eligible for the study. Data were collected surrounding pregnancy and birth histories, as well as any available genetic or metabolic testing including microarray, gene panels, whole-exome sequencing, and newborn metabolic screens. Twenty-eight patients had genetic testing such as microarray, whole-exome sequencing, or a gene panel, because of clinical suspicion. Ten of 28 patients had genetic mutations, including