22q11.2 Deletion-Associated Blood-Brain Barrier Permeability Potentiates Systemic Capillary Leak Syndrome Neurologic Features

Abstract

We present a case study of a young male with a history of 22q11.2 deletion syndrome (22qDS), diagnosed with systemic capillary leak syndrome (SCLS) who presented with acute onset of diffuse anasarca and sub-comatose obtundation. We hypothesized that his co-presentation of neurological sequelae might be due to blood-brain barrier (BBB) susceptibility conferred by the 22q11.2 deletion, a phenotype that we have previously identi ed in 22qDS. Using pre-and post-intravenous immunoglobulins (IVIG) patient serum, we studied circulating biomarkers of in ammation and assessed the potential susceptibility of the 22qDS BBB. We employed in vitro cultures of differentiated BBB-like endothelial cells derived from a 22qDS patient and a healthy control. We found evidence of peripheral in ammation and increased serum lipopolysaccharide (LPS) alongside endothelial cells in circulation. We report that the patient's serum signi cantly impairs barrier function of the 22qDS BBB compared to control. Only two other cases of pediatric SCLS with neurologic symptoms have been reported, and genetic risk factors have been suggested in both instances. As the third case to be reported, our ndings are consistent with the hypothesis that genetic susceptibility of the BBB conferred by the 22q11.2 deletion promoted neurologic involvement during SCLS in this patient.