Newborn Pulse Oximetry for Infants Born Out-of-Hospital.

BACKGROUND AND OBJECTIVES: Conventional timing of newborn pulse oximetry screening is not ideal for infants born out-of-hospital. We implemented a newborn pulse oximetry screen to align with typical midwifery care and measure its efficacy at detecting critical congenital heart disease. METHODS: Cohort study of expectant mothers and infants mainly from the Amish and Mennonite (Plain) communities with limited prenatal ultrasound use. Newborns were screened at 1 to 4 hours of life ("early screen") and 24 to 48 hours of life ("late screen"). Newborns were followed up to 6 weeks after delivery to report outcomes. Early screen, late screen, and combined results were analyzed on the basis of strict algorithm interpretation ("algorithm") and the midwife's interpretation in the field ("field") because these did not correspond in all cases. RESULTS: Pulse oximetry screening in 3019 newborns (85% Plain; 50% male; 43% with a prenatal ultrasound) detected critical congenital heart disease in 3 infants. Sensitivity of combined early and late screen was 66.7% (95% confidence interval [CI] 9.4% to 99.2%) for algorithm interpretation and 100% (95% CI 29.2% to 100%) for field interpretation. Positive predictive value was similar for the field interpretation (8.8%; 95% CI 1.9% to 23.7%) and algorithm interpretation (5.4%; 95% CI 0.7% to 18.2%). False-positive rates were ≤1.2% for both algorithm and field interpretations. Other pathologies (noncritical congenital heart disease, pulmonary issues, or infection) were reported in 12 of the false-positive cases. CONCLUSIONS: Newborn pulse oximetry can be adapted to the out-of-hospital setting without compromising sensitivity or prohibitively increasing false-positive rates.

Glutaric acidemia type 1: Treatment and outcome of 168 patients over three decades.

Glutaric acidemia type 1 (GA1) is a disorder of cerebral organic acid metabolism resulting from biallelic mutations of GCDH. Without treatment, GA1 causes striatal degeneration in >80% of affected children before two years of age. We analyzed clinical, biochemical, and developmental outcomes for 168 genotypically diverse GA1 patients managed at a single center over 31 years, here separated into three treatment cohorts: children in Cohort I (n = 60; DOB 2006-2019) were identified by newborn screening (NBS) and treated prospectively using a standardized protocol that included a lysine-free, arginine-enriched metabolic formula, enteral l-carnitine (100 mg/kg•day), and emergency intravenous (IV) infusions of dextrose, saline, and l-carnitine during illnesses; children in Cohort II (n = 57; DOB 1989-2018) were identified by NBS and treated with natural protein restriction (1.0-1.3 g/kg•day) and emergency IV infusions; children in Cohort III (n = 51; DOB 1973-2016) did not receive NBS or special diet. The incidence of striatal degeneration in Cohorts I, II, and III was 7%, 47%, and 90%, respectively (p < .0001). No neurologic injuries occurred after 19 months of age. Among uninjured children followed prospectively from birth (Cohort I), measures of growth, nutritional sufficiency, motor development, and cognitive function were normal. Adherence to metabolic formula and l-carnitine supplementation in Cohort I declined to 12% and 32%, respectively, by age 7 years. Cessation of strict dietary therapy altered plasma amino acid and carnitine concentrations but resulted in no serious adverse outcomes. In conclusion, neonatal diagnosis of GA1 coupled to management with lysine-free, arginine-enriched metabolic formula and emergency IV infusions during the first two years of life is safe and effective, preventing more than 90% of striatal injuries while supporting normal growth and psychomotor development. The need for dietary interventions and emergency IV therapies beyond early childhood is uncertain.

Diaminobutane (DAB) dendrimers are potent binders of oral phosphate.

Reduction of blood phosphorus is a critical component in the management of secondary hyperparathyroidism in chronic kidney disease patients. In addition to dialysis treatment and dietary phosphorus restriction, oral phosphate binders are often consumed with meals to reduce the availability of food phosphorus. Several oral phosphate binders are approved for use in chronic kidney disease patients, but all have practical limitations because of toxicity, poor efficacy, or high cost. Using an in vivo method to measure intestinal phosphate absorption in rats using radiolabeled phosphate, we found that first-, second-, third-, and fifth-generation diaminobutane dendrimer compounds, DAB-4-Cl, DAB-8-Cl, DAB-16-Cl, and DAB-64-Cl, respectively, drastically reduce the absorption of inorganic phosphate in a dose-dependent manner. To avoid complications of metabolic acidosis caused by hydrochloride salts, an acetate salt, DAB-9-AcOH, was prepared and shown to be equally effective at binding radiolabeled phosphate as DAB-8-Cl. DAB-8-AcOH was further shown to increase fecal phosphorus and decrease serum phosphorus in a dose-dependent manner when fed to rats. These data suggest that dendrimer compounds are of great potential use in the binding of food phosphate for the management of hyperparathyroidism secondary to chronic kidney disease.