Accurate indirect calorimetry studies can be performed in both ventilated and nonventilated infants weighing as little as 500 g, providing that sufficient attention is paid to technical and methodologic measurement details.

SouthSeq is a translational research study that undertook genome sequencing (GS) for infants with symptoms suggestive of a genetic disorder. Recruitment targeted racial/ethnic minorities and rural, medically underserved areas in the Southeastern United States, which are historically underrepresented in genomic medicine research. Methods: GS and analysis were performed for 367 infants to detect disease-causal variation concurrent with standard of care evaluation and testing. Results: Definitive diagnostic (DD) or likely diagnostic (LD) genetic findings were identified in 30% of infants, and 14% of infants harbored an uncertain result. Only 43% of DD/LD findings were identified via concurrent clinical genetic testing, suggesting that GS testing is better for obtaining early genetic diagnosis. We also identified phenotypes that correlate with the likelihood of receiving a DD/LD finding, such as craniofacial, ophthalmologic, auditory, skin, and hair abnormalities. We did not observe any differences in diagnostic rates between racial/ethnic groups. Conclusion:We describe one of the largest-to-date GS cohorts of ill infants, enriched for African American and rural patients. Our results show the utility of GS because it provides early-in-life detection of clinically relevant genetic variations not detected by current clinical genetic testing, particularly for infants exhibiting certain phenotypic features.

Human milk pH was measured in 309 samples obtained from 52 women who had delivered at term and lactated for as long as 10 months thereafter. The mean pH decreased from 7.45 for colostrum to a nadir of 7.04 during the second week of lactation. Thereafter, the pH of milk remained between 7.0 and 7.1 until 3 months postpartum and then increased gradually to 7.4 by 10 months. The change in hydrogen ion concentration in milk was associated with corresponding changes throughout lactation in the concentration of citrate but not with the concentration of lactose. Lactose concentration increased gradually for 3 weeks; the concentration of saturated medium-chain fatty acids increased more rapidly. One interpretation of these findings is that the hydrogen ions and citrate generated by mammary secretory cell metabolism are used after the second week of lactation for de novo synthesis of fatty acids more rapidly than they are synthesized. Milk samples from ruminants were found to have concentrations of hydrogen ions and citrate that are greater than and pH that is less than the respective measurements in human milk. The significance for the recipient infant of the predictable changes in human milk pH during lactation and of the higher pH of human milk throughout lactation relative to bovine milk is unknown. However, drug excretion into milk, milk enzyme activity, milk leukocyte function, and neonatal gastroin-testinal function are affected by ambient pH and may be influenced by the pH of milk.

OBJECTIVES: The American Academy of Pediatrics National Registry for the Surveillance and Epidemiology of Perinatal coronavirus disease 2019 (COVID-19) (NPC-19) was developed to provide information on the effects of perinatal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: National Registry for the Surveillance and Epidemiology of Perinatal COVID-19 participating centers entered maternal and newborn data for pregnant persons who tested positive for SARS-CoV-2 infection between 14 days before and 10 days after delivery. Incidence of and morbidities associated with maternal and newborn SARS-CoV-2 infection were assessed. RESULTS: From April 6, 2020 to March 19, 2021, 242 centers in the United States centers reported data for 7524 pregnant persons; at the time of delivery, 78.1% of these persons were asymptomatic, 18.2% were symptomatic but not hospitalized specifically for COVID-19, 3.4% were hospitalized for COVID-19 treatment, and 18 (0.2%) died in the hospital of COVID-related complications. Among 7648 newborns, 6486 (84.8%) were tested for SARS-CoV-2, and 144 (2.2%) were positive; the highest rate of newborn infection was observed when mothers first tested positive in the immediate postpartum period (17 of 125, 13.6%). No newborn deaths were attributable to SARS-CoV-2 infection. Overall, 15.6% of newborns were preterm: among tested newborns, 30.1% of polymerase chain reaction-positive and 16.2% of polymerase chain reaction-negative were born preterm (P < .001). Need for mechanical ventilation did not differ by newborn SARS-CoV-2 test result, but those with positive tests were more likely to be admitted to a NICU. CONCLUSIONS: Early in the pandemic, SARS-CoV-2 infection was acquired by newborns at variable rates and without apparent short-term effects. During a period that preceded widespread availability of vaccines, we observed higher than expected numbers of preterm births and maternal in-hospital deaths.