Isolated Upward Rotation of the Fetal Cerebellar Vermis (Blake’s Pouch Cyst) Is a Normal Variant: An Analysis of 111 Cases

<b><i>Introduction:</i></b> The objective of the study was to provide more detailed data about fetal isolated upward rotation of the cerebellar vermis rotation (Blake’s pouch cyst) in particular regarding pregnancy outcome. <b><i>Methods:</i></b> This is a retrospective study of all cases of fetal isolated upward rotation of the cerebellar vermis (URCV) diagnosed in 3 referral centers in Italy from January 2009 to November 2019. Whenever possible, prenatal magnetic resonance imaging (MRI) was performed and a fetal karyotype was obtained. A detailed follow-up was obtained by consultation of medical records, interview with the parents, and the pediatricians. <b><i>Results:</i></b> Our study population included 111 patients with a prenatal diagnosis of isolated URCV made at a median gestational age of 21 weeks +3 days (interquartile range (IQR) 21 + 0–22 + 2). The median brain stem-vermis (BV) angle was 27° (IQR 24–29°). In 37.9% of the cases, a regression of the finding with restoration of normal anatomy was noted at a follow-up scan or at postnatal checks. A BV angle of 25° or less predicted regression with a probability in excess of 90%. MRI was performed in utero or at birth in 101 patients and always confirmed sonographic diagnosis. Fetal CGH array and/or karyotype was available in 97 cases and was always normal, but in 1 case. A postnatal follow-up was available in 102 infants (mean 7 months, range 0–10 years of age) and documented a normal neurologic development in all the cases. <b><i>Conclusions:</i></b> Isolated URCV is most likely a normal variant of fetal anatomy without clinical consequences, at least at an early follow-up. A BV angle of 25° or less predicts intrauterine regression of the finding, but the outcome is good in all the cases. When a confident sonographic diagnosis is made, MRI is not mandatory. The risk of a chromosomal anomaly in these cases is probably low.

Antepartum COVID-19 and Postpartum Autism

A little over a year ago, a new viral disease appeared worldwide. Much like earlier pathologic RNA viruses, Covid-19 can cause distinctive harmful effects on pregnant women and their offspring. Because of the coexistent fever associated with a rise in pro-inflammatory interleukins in the most severe cases, there is a serious concern about the baby’s neurologic development. Although not yet observed in many Covid-19 pregnancies, it is anticipated particularly that the onset of autism in the child may be realized in a year or more postpartum. Prior studies have reported that exclusive breast-feeding which provides a good source of IGF1 for the baby may well reduce the incidence of autism in such cases.

Shake It Baby

Every neonate undergoes normal physiologic hypoglycemia within the first few hours of birth given the unique transition between glucose sources. In utero, the mother is the primary source of glucose while, after birth, the newborn slowly transitions to gluconeogenesis, glycogenolysis, and oral feeds to help maintain blood sugar. Though determination of physiologic and pathologic hypoglycemia necessitating treatment may be difficult within the first few hours of life, it is an important one. There are numerous causes of hypoglycemia including maternal diabetes, congenital adrenal hyperplasia, and neonatal stress, among others. It is important to determine the etiology of hypoglycemia, as the prevention of recurrent hypoglycemia is important for neurologic development. Symptoms of hypoglycemia are nonspecific and can be indicative of other disease pathology such as sepsis. Symptoms include high pitched cry, poor suck, lethargy, coma, irritability, and inconsolability, among others. Long-term sequelae for babies with recurrent hypoglycemia and symptomatic hypoglycemia are mainly neurodevelopmental in nature. It is therefore of utmost importance to ensure that proper treatment is initiated to infants necessitating treatment.

Directed evolution of a sphingomyelin flippase reveals mechanism of substrate backbone discrimination by a P4-ATPase

Phospholipid flippases in the type IV P-type ATPase (P4-ATPases) family establish membrane asymmetry and play critical roles in vesicular transport, cell polarity, signal transduction, and neurologic development. All characterized P4-ATPases flip glycerophospholipids across the bilayer to the cytosolic leaflet of the membrane, but how these enzymes distinguish glycerophospholipids from sphingolipids is not known. We used a directed evolution approach to examine the molecular mechanisms through which P4-ATPases discriminate substrate backbone. A mutagenesis screen in the yeast Saccharomyces cerevisiae has identified several gain-of-function mutations in the P4-ATPase Dnf1 that facilitate the transport of a novel lipid substrate, sphingomyelin. We found that a highly conserved asparagine (N220) in the first transmembrane segment is a key enforcer of glycerophospholipid selection, and specific substitutions at this site allow transport of sphingomyelin.