Proposed Screening for Congenital Hyperinsulinism in Newborns: Perspective from a Neonatal-Perinatal Medicine Group.

This perspective work by academic neonatal providers is written specifically for the audience of newborn care providers and neonatologists involved in neonatal hypoglycemia screening. Herein, we propose adding a screen for congenital hyperinsulinism (CHI) by measuring glucose and ketone (i.e., ß-hydroxybutyrate (BOHB)) concentrations just prior to newborn hospital discharge and as close to 48 h after birth as possible, at the same time that the mandated state Newborn Dried Blood Spot Screen is obtained. In the proposed protocol, we do not recommend specific metabolite cutoffs, as our primary objective is to simply highlight the concept of screening for CHI in newborns to newborn caregivers. The premise for our proposed screen is based on the known effect of hyperinsulinism in suppressing ketogenesis, thereby limiting ketone production. We will briefly discuss genetic CHI, other forms of neonatal hypoglycemia, and their shared mechanisms; the mechanism of insulin regulation by functional pancreatic islet cell membrane KATP channels; adverse neurodevelopmental sequelae and brain injury due to missing or delaying the CHI diagnosis; the principles of a good screening test; how current neonatal hypoglycemia screening programs do not fulfill the criteria for being effective screening tests; and our proposed algorithm for screening for CHI in newborns.

A Deep Intronic PKHD1 Variant Identified by SpliceAI in a Deceased Neonate With Autosomal Recessive Polycystic Kidney Disease.

The etiologies of newborn deaths in neonatal intensive care units usually remain unknown, even after genetic testing. Whole-genome sequencing, combined with artificial intelligence-based methods for predicting the effects of non-coding variants, provide an avenue for resolving these deaths. Using one such method, SpliceAI, we identified a maternally inherited deep intronic PKHD1 splice variant (chr6:52030169T>C), in trans with a pathogenic missense variant (p.Thr36Met), in a newborn who died of autosomal recessive polycystic kidney disease at age 2 days. We validated the deep intronic variant's impact in maternal urine-derived cells expressing PKHD1. Reverse transcription polymerase chain reaction followed by Sanger sequencing showed that the variant causes inclusion of 147bp of the canonical intron between exons 29 and 30 of PKHD1 into the mRNA, including a premature stop codon. Allele-specific expression analysis at a heterozygous site in the mother showed that the mutant allele completely suppresses canonical splicing. In an unrelated healthy control, there was no evidence of transcripts including the novel splice junction. We returned a diagnostic report to the parents, who underwent in vitro embryo selection.

Diagnostic criteria of acute rheumatic fever.

Acute rheumatic fever is an inflammatory sequela of Group A Streptococcal pharyngitis that affects multiple organ systems. The incidence of acute rheumatic fever has been declining even before the use of antibiotics became widespread, however the disease remains a significant cause of morbidity and mortality in children, particularly in developing countries and has been estimated to affect 19 per 100,000 children worldwide. Acute rheumatic fever is a clinical diagnosis, and therefore subject to the judgment of the clinician. Because of the variable presentation, the Jones criteria were first developed in 1944 to aid clinicians in the diagnosis of acute rheumatic fever. The Jones criteria have been modified throughout the years, most recently in 1992 to aid clinicians in the diagnosis of initial attacks of acute rheumatic fever and to minimize overdiagnosis of the disease. Diagnosis of acute rheumatic fever is based on the presence of documented preceding Group A Streptococcal infection, in addition to the presence of two major manifestations or one major and two minor manifestations of the Jones criteria. Without documentation of antecedent Group A Streptococcal infection, the diagnosis is much less likely except in a few rare scenarios. Carditis, polyarthritis and Sydenham's chorea are the most common major manifestations of acute rheumatic fever. However, despite the predominance of these major manifestations of acute rheumatic fever, there can be significant overlap with other disorders such as Lyme disease, serum sickness, drug reactions, and post-Streptococcal reactive arthritis. This overlap between disease processes has led to continued investigation of the pathophysiology as well as development of new biomarkers and laboratory studies to aid in the diagnosis of acute rheumatic fever and distinction from other disease processes.