Intrahepatic portosystemic shunts, from prenatal diagnosis to postnatal outcome: a retrospective study.

OBJECTIVE: Congenital intrahepatic portosystemic shunts (IHPSS) are rare vascular malformations resulting in blood bypassing the liver to the systemic circulation. Previous studies included symptomatic patients diagnosed postnatally, but the outcome of IHPSS diagnosed prenatally is rarely reported. We present a cohort of children prenatally diagnosed with IHPSS and report their natural course and outcome. METHODS AND DESIGN: This was a retrospective study of all fetal cases diagnosed by ultrasound with IHPSS between 2006 and 2019 at a single tertiary centre which were prospectively followed up at the paediatric gastroenterology unit. The postnatal outcome was compared between patients with a single versus multiple intrahepatic shunts. RESULTS: Twenty-six patients (70.3% boys) were included in the study, of them, eight (30.8%) patients had multiple intrahepatic shunts. The median gestational age at diagnosis was 29.5 weeks. Growth restriction affected 77% of the cohort. Postnatally, spontaneous shunt closure occurred in 96% of patients at a median age of 7.5 months (IQR 2.2-20 months). Failure to thrive (FTT) and mild developmental delay were observed in eight (30.8%) and seven (26.9%) patients, respectively. FTT was significantly more prevalent in patients with multiple shunts compared with patients with a single shunt (62.5% vs 16.7%, p=0.02); however, the rate of shunt closure and age at time of closure were similar between these groups. All patients survived with limited to no sequelae. CONCLUSIONS: IHPSS usually close spontaneously by 2 years of age. Children with prenatally detected IHPSS may develop FTT and mild developmental delay. Close surveillance at a paediatric gastroenterology unit may be beneficial.

Glycogen Storage Disease type IA refractory to cornstarch: Can next generation sequencing offer a solution?

Avoidance of fasting and regular ingestion of uncooked-cornstarch have long been the mainstay dietary treatment of Glycogen Storage Disease type Ia (GSD-Ia). However, GSD-Ia patients who despite optimal dietary treatment show poor glycemic control and are intolerant to cornstarch, present a complex clinical challenge. We pursued Whole Exome Sequencing (WES) in three such unrelated patients, to both confirm a molecular diagnosis of GSD-Ia, and seek additional variants in other genes (e.g. genes associated with amylase production) which may explain their persistent symptoms. WES confirmed the GSD-Ia diagnosis, with all three probands harboring the homozygous p.R83C variant in G6PC. While no other significant variants were identified for patients A and B, a homozygous p.G276V variant in the SI gene was detected in patient C, establishing the dual-diagnosis of GSD-Ia and Sucrase-Isomaltase Deficiency. To conclude, we suggest that WES should be considered in GSD-Ia patients who show persistent symptoms despite optimal dietary management.