Case Series: Hyperbilirubinemia under elexacaftor/tezacaftor/ivacaftor in the presence of Gilbert's syndrome.

Liver-related side effects are a known complication of treatment with elexacaftor/tezacaftor/ivacaftor (ETI) for cystic fibrosis (CF). Gilbert's syndrome is caused by a genetic mutation that reduces activity of the enzyme UDP glucuronosyltransferase 1 polypeptide A1 (UGT1A1), causing elevated levels of unconjugated bilirubin in the blood and duodenal bile. The presence of Gilbert's syndrome and CF might represent additive risk factors for liver-related adverse events during ETI treatment. This case series describes six people with CF (pwCF) in whom previously unknown Gilbert's syndrome was unmasked after initiation of treatment with ETI. Although all patients had some level of hepatic dysfunction and/or elevated levels of bilirubin after initiation of ETI, the clinical course varied. Only one patient had to stop ETI therapy altogether, while the others were able to continue treatment (some at a reduced dosage and others at the full recommended daily dosage). All patients, even those using a lower dosage, experienced clinical benefit during ETI therapy. Gilbert's syndrome is not a contraindication for ETI therapy but may be mistaken for a risk factor for liver-related adverse events in pwCF. This is something that physicians need to be aware of in pwCF who show liver adverse events during ETI therapy.

Unconjugated Hyperbilirubinemia in Acetaminophen-Related Acute Liver Failure.

BACKGROUND In the absence of liver transplantation, the natural history of acetaminophen-induced liver failure is characterized by a progressive increase of liver function tests, including bilirubin mainly as its conjugated form. The presence of high levels of unconjugated bilirubin is more unusual; its etiology is unclear and its prognostic factor has been poorly investigated. CASE REPORT A 52-year-old man with a history of chronic analgesics, alcohol, and illicit drug abuse developed acute liver failure in relationship with the ingestion of largely supra-therapeutic doses of acetaminophen over the days preceding admission. The patient received the classical N-acetylcysteine treatment regimen for acetaminophen overdose. Clinical course was characterized by a progressive worsening of the neurological condition, evolving to grade IV encephalopathy. Coagulation disorders persisted, with factor V level <10%. He fulfilled the criteria for liver transplantation, but this option was rejected after a careful psychiatric evaluation. Laboratory investigations revealed a progressive increase in serum unconjugated bilirubin until his death. As evidence for hemolysis was lacking, acquired deficit in bilirubin glucuronidation appeared likely and diagnosis of Gilbert's syndrome was excluded. CONCLUSIONS After the exclusion of other causes of high unconjugated bilirubin levels, the progressive increase in unconjugated bilirubin can reflect a persistent defect in bilirubin conjugation in relationship with liver centrilobular injury, but the relationship with acetaminophen-glucuronidation is not known and there are insufficient data to affirm that the ratio unconjugated/conjugated bilirubin could be used as a prognostic factor.

Association Between Intrapartum Nitrous Oxide for Labor Analgesia and Short-Term Neonatal Outcomes.

OBJECTIVE: To evaluate the association between intrapartum nitrous oxide use and adverse short-term neonatal outcomes. METHODS: This was a retrospective cohort study of individuals with singleton gestations at 35 or more weeks who attempted labor and delivered at an academic hospital between June 1, 2015, and February 28, 2020. Data were extracted from the electronic medical record using billing and diagnostic codes. Patients were classified based on whether they received no intrapartum analgesia or received nitrous oxide only. Those who received other analgesia types were excluded. The primary outcome was neonatal intensive care unit (NICU) admission. Secondary outcomes included Apgar score less than 7 at 1 minute and 5 minutes, respiratory composite outcome (including meconium aspiration syndrome, neonatal bronchopulmonary disorders, neonatal transient tachypnea, and other neonatal respiratory distress that required NICU admission), hypoglycemia, and hyperbilirubinemia. Univariable and multivariable analyses were used to estimate the association between nitrous oxide exposure intrapartum and the selected outcomes. RESULTS: Of 6,047 included, 4,153 (68.7%) received no analgesia, and 1,894 (31.3%) received nitrous oxide only. In comparison with individuals who received no analgesia, those who received nitrous oxide were more likely to be nulliparous, be of Black racial identity, have noncommercial insurance, and be less likely to deliver by intrapartum cesarean. The reception of nitrous oxide, compared with the reception of no analgesia, was associated with a lower likelihood of NICU admission (6.4% vs 8.1%; adjusted odds ratio [aOR] 0.77, 95% CI, 0.62-0.96) and an increased likelihood of neonatal hyperbilirubinemia (aOR 1.23, 95% CI, 1.08-1.41). Inhaled nitrous oxide exposure, in comparison with the reception of no analgesia, was not associated with the other secondary outcomes, including Apgar score less than 7 at 1 minute (odds ratio [OR] 0.74, 95% CI, 0.50-1.10) or 5 minutes (OR 0.91, 95% CI, 0.32-2.60), respiratory composite outcome (OR 0.91, 95% CI, 0.70-1.17), and hypoglycemia (OR 0.82, 95% CI, 0.64-1.05). CONCLUSION: In this single-center retrospective cohort of low-risk patients, intrapartum inhaled nitrous oxide, compared with the reception of no analgesia, was associated with a decreased risk for NICU admission but with an increased risk for hyperbilirubinemia; other outcomes did not differ. These findings may be used to counsel patients when considering nitrous oxide for labor analgesia.

Three or four doses of intravenous immunoglobulin G treatment for isoimmune hemolytic disease: A case series and literature review.

BACKGROUND: Neonates affected by isoimmune hemolytic disease (HDN) are at risk of developing severe hyperbilirubinemia. Studies show that increasing levels of bilirubin impact neonatal neurodevelopment. To avoid complications associated with exchange transfusion, intravenous immunoglobulin G (IVIG) is used to treat hyperbilirubinemia. We included all infants who received more than two doses of IVIG treatment for isoimmune hemolytic disease. We analyzed the incidence of side effects associated with IVIG treatment and the rate of exchange transfusion. METHODS: A retrospective chart review performed between October 2011-October 2022 at East Carolina University Health identified neonates who received more than two doses IVIG for HDN. Neonates of postmenstrual age greater than 28 days old, receiving less than three doses of IVIG or received IVIG for other indications were excluded. The occurrences of adverse events, demographics and use of other medical therapies were reviewed. RESULTS: Eleven neonates were included in the case series. Most common cause of severe hyperbilirubinemia was attributed to ABO incompatibility. Six patients (54%) received three doses of IVIG, and five patients (45%) received four doses of IVIG with bilirubin levels decreasing below exchange transfusion. No treatment exceeding four doses of IVIG was reported, nor adverse events during treatment. CONCLUSIONS: In this cohort of neonates with HDN, bilirubin levels decreased after treatment with multiple doses of IVIG. Future research on recommendations of optimal total number doses of IVIG to reduce the risk for exchange transfusion.