Detection of subclinical Harlequin syndrome in pediatric patients.

Background: Harlequin syndrome presents as differences in facial coloring due to unilateral flushing. This is the result of the inability to flush on the affected side due to the disruption of vasomotor and sudomotor sympathetic activity. The neurologically intact side appears flushed.

Haptoglobin phenotype predicts the development of focal and global cerebral vasospasm and may influence outcomes after aneurysmal subarachnoid hemorrhage.

Cerebral vasospasm (CV) and the resulting delayed cerebral ischemia (DCI) significantly contribute to poor outcomes following aneurysmal subarachnoid hemorrhage (aSAH). Free hemoglobin (Hb) within the subarachnoid space has been implicated in the pathogenesis of CV. Haptoglobin (Hp) binds free pro-oxidant Hb, thereby modulating its harmful effects.

Clinical Implications of Bilirubin-Associated Neuroprotection and Neurotoxicity.

Bilirubin is a primary product of heme catabolism and exhibits both neuroprotective and neurotoxic effects. When present at physiologic concentrations, bilirubin is a potent antioxidant and serves to protect brain tissue from oxidative stress insults. The use of the anesthetic propofol attenuates ischemic injury in rats by exploiting these neuroprotective properties.