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World Journal of Gastroenterology Sep 2023Delayed passage of meconium or constipation during the perinatal period is traditionally regarded as a signal to initiate further work up to evaluate for serious... (Review)
Review
Delayed passage of meconium or constipation during the perinatal period is traditionally regarded as a signal to initiate further work up to evaluate for serious diagnoses such as Hirschsprung's disease (HD), meconium ileus due to Cystic Fibrosis, The diagnosis of HD particularly warrants invasive testing to confirm the diagnosis, such as anorectal manometry or rectal suction biopsy. What if there was another etiology of perinatal constipation, that is far lesser known? Cow's milk protein allergy (CMPA) is often diagnosed in infants within the first few weeks of life, however, there are studies that show that the CMPA allergen can be passed from mother to an infant in-utero, therefore allowing symptoms to show as early as day one of life. The presentation is more atypical, with perinatal constipation rather than with bloody stools, diarrhea, and vomiting. The diagnosis and management would be avoidance of cow's milk protein within the diet, with results and symptom improvement in patients immediately. Therefore, we discuss whether an alternative pathway to address perinatal constipation should be further discussed and implemented to potentially avoid invasive techniques in patients. This entails first ruling out CMPA with safe, noninvasive techniques with diet modification, and if unsuccessful, then moving forward with further diagnostic modalities.
Topics: Animals; Cattle; Female; Infant; Pregnancy; Humans; Milk Hypersensitivity; Constipation; Biopsy; Diarrhea; Hirschsprung Disease
PubMed: 37731998
DOI: 10.3748/wjg.v29.i33.4920 -
Channels (Austin, Tex.) Dec 2023SLC26A9 is one out of 11 proteins that belong to the SLC26A family of anion transporters. Apart from expression in the gastrointestinal tract, SLC26A9 is also found in... (Review)
Review
SLC26A9 is one out of 11 proteins that belong to the SLC26A family of anion transporters. Apart from expression in the gastrointestinal tract, SLC26A9 is also found in the respiratory system, in male tissues and in the skin. SLC26A9 has gained attention because of its modifier role in the gastrointestinal manifestation of cystic fibrosis (CF). SLC26A9 appears to have an impact on the extent of intestinal obstruction caused by meconium ileus. SLC26A9 supports duodenal bicarbonate secretion, but was assumed to provide a basal Cl- secretory pathway in airways. However, recent results show that basal airway Cl- secretion is due to cystic fibrosis conductance regulator (CFTR), while SLC26A9 may rather secrete HCO-, thereby maintaining proper airway surface liquid (ASL) pH. Moreover, SLC26A9 does not secrete but probably supports reabsorption of fluid particularly in the alveolar space, which explains early death by neonatal distress in Slc26a9-knockout animals. While the novel SLC26A9 inhibitor S9-A13 helped to unmask the role of SLC26A9 in the airways, it also provided evidence for an additional role in acid secretion by gastric parietal cells. Here we discuss recent data on the function of SLC26A9 in airways and gut, and how S9-A13 may be useful in unraveling the physiological role of SLC26A9.
Topics: Animals; Biological Transport; Cystic Fibrosis; Intestines; Respiratory System; Sulfate Transporters; Antiporters
PubMed: 36866602
DOI: 10.1080/19336950.2023.2186434 -
JCI Insight Apr 2024Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene, with F508del being the most prevalent mutation. The combination of...
Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene, with F508del being the most prevalent mutation. The combination of CFTR modulators (potentiator and correctors) has provided benefit to CF patients carrying the F508del mutation; however, the safety and effectiveness of in utero combination modulator therapy remains unclear. We created a F508del ferret model to test whether ivacaftor/lumacaftor (VX-770/VX-809) therapy can rescue in utero and postnatal pathologies associated with CF. Using primary intestinal organoids and air-liquid interface cultures of airway epithelia, we demonstrate that the F508del mutation in ferret CFTR results in a severe folding and trafficking defect, which can be partially restored by treatment with CFTR modulators. In utero treatment of pregnant jills with ivacaftor/lumacaftor prevented meconium ileus at birth in F508del kits and sustained postnatal treatment of CF offspring improved survival and partially protected from pancreatic insufficiency. Withdrawal of ivacaftor/lumacaftor treatment from juvenile CF ferrets reestablished pancreatic and lung diseases, with altered pulmonary mechanics. These findings suggest that in utero intervention with a combination of CFTR modulators may provide therapeutic benefits to individuals with F508del. This CFTR-F508del ferret model may be useful for testing therapies using clinically translatable endpoints.
Topics: Animals; Female; Pregnancy; Aminophenols; Aminopyridines; Benzodioxoles; Chloride Channel Agonists; Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator; Disease Models, Animal; Drug Combinations; Ferrets; Mutation; Quinolones
PubMed: 38646935
DOI: 10.1172/jci.insight.157229 -
Frontiers in Pediatrics 2024Meconium ileus (MI) is a life-threatening obstruction of the intestines affecting ∼15% of newborns with cystic fibrosis (CF). Current medical treatments for MI often...
INTRODUCTION
Meconium ileus (MI) is a life-threatening obstruction of the intestines affecting ∼15% of newborns with cystic fibrosis (CF). Current medical treatments for MI often fail, requiring surgical intervention. MI typically occurs in newborns with pancreatic insufficiency from CF. Meconium contains mucin glycoprotein, a potential substrate for pancreatic enzymes or mucolytics. Our study aim was to determine whether pancreatic enzymes in combination with mucolytic treatments dissolve obstructive meconium using the CF pig model.
METHODS
We collected meconium from CF pigs at birth and submerged it in solutions with and without pancreatic enzymes, including normal saline, 7% hypertonic saline, and the reducing agents N-acetylcysteine (NAC) and dithiothreitol (DTT). We digested meconium at 37 °C with agitation, and measured meconium pigment release by spectrophotometry and residual meconium solids by filtration.
RESULTS AND DISCUSSION
In CF pigs, meconium appeared as a solid pigmented mass obstructing the ileum. Meconium microscopically contained mucus glycoprotein, cellular debris, and bile pigments. Meconium fragments released pigments with maximal absorption at 405 nm after submersion in saline over approximately 8 h. Pancreatic enzymes significantly increased pigment release and decreased residual meconium solids. DTT did not improve meconium digestion and the acidic reducing agent NAC worsened digestion. Pancreatic enzymes digested CF meconium best at neutral pH in isotonic saline. We conclude that pancreatic enzymes digest obstructive meconium from CF pigs, while hydrating or reducing agents alone were less effective. This work suggests a potential role for pancreatic enzymes in relieving obstruction due to MI in newborns with CF.
PubMed: 38665380
DOI: 10.3389/fped.2024.1387171 -
European Journal of Pediatrics Sep 2023Necrotizing enterocolitis (NEC) is associated with significant morbidity and mortality in preterm infants. Early recognition and treatment of NEC are critical to...
UNLABELLED
Necrotizing enterocolitis (NEC) is associated with significant morbidity and mortality in preterm infants. Early recognition and treatment of NEC are critical to improving outcomes. Enteric nervous system (ENS) immaturity has been proposed as a key factor in NEC pathophysiology. Gastrointestinal dysmotility is associated with ENS immaturity and may serve as a predictive factor for the development of NEC. In this case-control study, preterm infants (gestational age (GA) < 30 weeks) were included in two level-IV neonatal intensive care units. Infants with NEC in the first month of life were 1:3 matched to controls based on GA (± 3 days). Odds ratios for NEC development were analyzed by logistic regression for time to first passage of meconium (TFPM), duration of meconial stool, and mean daily defecation frequency over the 72 h preceding clinical NEC onset (DF < T0). A total of 39 NEC cases and 117 matched controls (median GA 27 + 4 weeks) were included. Median TFPM was comparable in cases and controls (36 h [IQR 13-65] vs. 30 h [IQR 9-66], p = 0.83). In 21% of both cases and controls, TFPM was ≥ 72 h (p = 0.87). Duration of meconial stool and DF < T0 were comparable in the NEC and control group (median 4 and 3, resp. in both groups). Odds of NEC were not significantly associated with TFPM, duration of meconial stools, and DF < T0 (adjusted odds ratio [95% confidence interval]: 1.00 [0.99-1.03], 1.16 [0.86-1.55] and 0.97 [0.72-1.31], resp.).
CONCLUSION
In this cohort, no association was found between TFPM, duration of meconium stool, and DF < T0 and the development of NEC.
WHAT IS KNOWN
• Necrotizing enterocolitis (NEC) is a life-threatening acute intestinal inflammatory disease of the young preterm infant. Early clinical risk factors for NEC have been investigated in order to facilitate early diagnosis and treatment. • Signs of disrupted gastrointestinal mobility, such as gastric retention and paralytic ileus, have been established to support the diagnosis of NEC. Nevertheless, defecation patterns have insufficiently been studied in relation to the disease.
WHAT IS NEW
• Defecation patterns in the three days preceding NEC did not differ from gestational age-matched controls of corresponding postnatal age. Additionally, the first passage of meconium and the duration of meconium passage were comparable between cases and controls. Currently, defecation patterns are not useful as early warning signs for NEC. It remains to be elucidated whether these parameters are different based on the location of intestinal necrosis.
PubMed: 37349579
DOI: 10.1007/s00431-023-05035-8 -
The Journal of Biological Chemistry Jan 2024Mutations in receptor guanylyl cyclase C (GC-C) cause severe gastrointestinal disease, including meconium ileus, early onset acute diarrhea, and pediatric inflammatory...
Mutations in receptor guanylyl cyclase C (GC-C) cause severe gastrointestinal disease, including meconium ileus, early onset acute diarrhea, and pediatric inflammatory bowel disease that continues into adulthood. Agonists of GC-C are US Food and Drug Administration-approved drugs for the treatment of constipation and irritable bowel syndrome. Therapeutic strategies targeting GC-C are tested in preclinical mouse models, assuming that murine GC-C mimics human GC-C in its biochemical properties and downstream signaling events. Here, we reveal important differences in ligand-binding affinity and GC activity between mouse GC-C and human GC-C. We generated a series of chimeric constructs of various domains of human and mouse GC-C to show that the extracellular domain of mouse GC-C contributed to log-orders lower affinity of mouse GC-C for ligands than human GC-C. Further, the Vmax of the murine GC domain was lower than that of human GC-C, and allosteric regulation of the receptor by ATP binding to the intracellular kinase-homology domain also differed. These altered properties are reflected in the high concentrations of ligands required to elicit signaling responses in the mouse gut in preclinical models and the specificity of a GC inhibitor towards human GC-C. Therefore, our studies identify considerations in using the murine model to test molecules for therapeutic purposes that work as either agonists or antagonists of GC-C, and vaccines for the bacterial heat-stable enterotoxin that causes watery diarrhea in humans.
Topics: Animals; Child; Humans; Mice; Diarrhea; Enterotoxins; Guanylate Cyclase; Ligands; Receptors, Enterotoxin; Receptors, Guanylate Cyclase-Coupled; Gastrointestinal Diseases
PubMed: 38029963
DOI: 10.1016/j.jbc.2023.105505 -
Balkan Journal of Medical Genetics :... Jul 2023Pre-implantation genetic diagnosis (PGD) is not often performed when donor gametes are used, due to its high cost. This is with the presumption that the donors are...
Pre-implantation genetic diagnosis (PGD) is not often performed when donor gametes are used, due to its high cost. This is with the presumption that the donors are healthy. We report on five cases of babies with confirmed cystic fibrosis (CF), being the result from in vitro fertilization (IVF) with donor (4 cases) or own gametes (one case). There has been no family history for CF in any of the families affected. The clinical presentation in the children ranged from meconium ileus to recurrent respiratory infections and severe nasal polyposis. The age of diagnosis also varied from birth until 9 years. Since one of the presented cases was discovered in a very renowned private IVF clinic, the clinic changed their own protocol, and currently they test every donor for CF carriership. The percentage of CF carriers in the donor population is roughly the same as the one predicted in the general population of Bulgaria - 1/33. Although PGD is costly, the costs for proper care for a CF patient are currently much higher. The more economical option would to screen every donor for CF carriership. IVF requires a lot of physical and psychological stamina. The couples that go through this procedure also require a great deal of hope. It is essential to be more preconscious for possible congenital diseases. We advocate every IVF center to test the donors for CF carriership or to provide PGD for their clients.
PubMed: 37576787
DOI: 10.2478/bjmg-2023-0001 -
Radiology Case Reports May 2024Etiologies underlying the relatively infrequent third-trimester sonographic depiction of dilated fetal bowel include (functional or mechanical) bowel obstruction,...
Etiologies underlying the relatively infrequent third-trimester sonographic depiction of dilated fetal bowel include (functional or mechanical) bowel obstruction, intestinal atresia, volvulus, annular pancreas, intestinal malrotation, intussusception, gastrointestinal duplications, cystic fibrosis-associated meconium ileus, congenital chloride diarrhea, microvillus inclusion disease, intestinal neuronal dysplasia, and meconium plug syndrome. Fetal bowel obstruction may be associated with aneuploidy (mostly Trisomy 21 in association with esophageal or duodenal atresia), and rarely select microduplications or deletions. We present unusual sonographic findings associated with transient marked proximal fetal bowel dilatation in association with concurrent development of oligohydramnios, in a growth-restricted fetus at 35 weeks' gestation. This case supports that upon observation of dilated loops of fetal bowel, while not negating the potential need for delivery secondary to potential bowel compromise, consideration should be given for observation in anticipation of potential spontaneous resolution of this condition, especially among growth-restricted fetuses with decreased amniotic fluid volume in prematurity.
PubMed: 38384702
DOI: 10.1016/j.radcr.2024.01.069