Parenteral nutrition associated cholestasis is earlier, more prolonged and severe in small for gestational age compared with appropriate for gestational age very low birth weight infants

Recovery from parenteral nutrition-associated cholestasis takes approximately two months in very low birth weight infants

AIM

To investigate the clinical characteristics and course of parenteral nutrition-associated cholestasis (PNAC) in very low birth weight (VLBW) infants.

METHODS

The charts of VLBW infants were retrospectively reviewed. The clinical characteristics of infants with and without PNAC were compared, trends in liver enzymes were investigated, and the characteristics of infants with PNAC were analysed based on age of onset.

RESULTS

PNAC was observed in 53 (13.2%) of 403 infants who survived and completed follow-up and was associated with significantly lower gestational age, birth weight, and adverse neonatal outcomes. PNAC started at a median 32 (interquartile range 23-47) days, PN was applied for 53 (34.5-64.5) days, the maximum direct bilirubin (DB) was observed at 63 (50-76) postnatal days, and PNAC resolved at 94 (79-122) postnatal days postnatal age. PNAC lasted 61 (38-89.5) days. AST and ALT normalised at 111 (100.3-142.0) and 109.5 (97-161.3) postnatal days. Infants with early-onset PNAC had significantly longer PN duration, higher maximum DB, and higher maximum AST than those with late-onset PNAC.

CONCLUSION

Elevated DB, AST, and ALT persist for a long period after discontinuing PN. We suggest a cautious approach that involves waiting and reducing the frequency of additional repetitive examinations.

Cholestasis after very preterm birth was associated with adverse neonatal outcomes but no significant long-term liver disease: A population-based study

AIM

To describe outcome linked to neonatal cholestasis in a defined cohort of very preterm infants.

METHODS

Population-based retrospective case-control study of preterm infants, gestational age <30 weeks, surviving for 28 days, in Stockholm County. Cholestasis was defined as conjugated bilirubin ≥30 μmol/L exceeding 20% of total level at least twice and graded as high if exceeding 100 μmol/L. Cholestatic cases were matched on gestational week with two non-cholestatic controls.

RESULTS

The incidence rate of cholestasis was 37/250 (14.8%), with increasing rates in lower gestational weeks. Perinatal factors associated with cholestasis were pre-eclampsia and being born small for gestational age. Cholestatic infants had three times more bronchopulmonary dysplasia and eight times more retinopathy of prematurity. The mortality was 13.5% in cholestatic infants versus 2.7% in controls (P = .040). All deceased cholestatic infants had high-grade cholestasis. No surviving infants developed chronic liver disease by 10 years of age.

CONCLUSION

Cholestasis was common in very preterm infants and linked to disease severity and adverse outcome. Cholestasis may be an independent risk factor for bronchopulmonary dysplasia and retinopathy of prematurity and more severe cholestasis associated with increased mortality. Cholestasis was not associated with chronic liver disease later in childhood.

Risk factors of parenteral nutrition-associated cholestasis in very-low-birthweight infants

AIM

We aimed to explore risk factors associated with parenteral nutrition-associated cholestasis (PNAC) in very-low-birthweight (VLBW) infants.

METHODS

VLBW infants receiving parenteral nutrition (PN) for at least 14 days were enrolled in a retrospective dual-centre study and divided into two groups chronologically: group A (2000-2007) and group B (2008-2015). The incidence of PNAC and related factors were investigated. We compared the differences between PNAC and non-PNAC groups. A multivariate binary logistic regression analysis was carried out to identify the potential risk factors of PNAC.

RESULTS

A total of 387 VLBW infants (53 in group A and 334 in group B) were enrolled in the study. The total incidence of PNAC was 6.7%, 9.4% in group A and 6.3% in group B. The dosage of amino acid (P = 0.009), glucose (P = 0.006), PN calories (P = 0.021) and the ratio of glucose/fat (P = 0.014) were significantly higher in group B than in group A. Non-protein energy to nitrogen ratio (P = 0.017) was lower in group B. Birthweight was significantly lower in the PNAC group than in the non-PNAC group (P = 0.021). Subgroup analysis showed that gestational age and duration of PN were significantly different between the PNAC and non-PNAC groups (P < 0.05). Logistic regression showed that prolonged duration of PN (≥43 days) (odds ratio 3.155, 95% confidence interval 1.009-9.861, P = 0.048) was an independent risk factor of PNAC.

CONCLUSIONS

For VLBW infants, prolonged duration of PN is a risk factor for the development of PNAC. PNAC may be prevented by weaning off PN as early as possible in VLBW infants.

Fecal Microbiomes in Premature Infants With and Without Parenteral Nutrition-Associated Cholestasis

INTRODUCTION

Premature infants often require parenteral nutrition (PN) until they reach enteral autonomy which puts them at risk of developing PN-associated cholestasis (PNAC). We sought to compare longitudinal changes in fecal microbiomes of premature infants who developed PNAC versus those who did not despite being on similar PN doses.

METHODS

Stool samples from premature infants (gestational age <30 weeks) who developed direct bilirubin ≥1.5 mg/dL while receiving PN were classified as precholestasis, cholestasis, or postcholestasis based on bilirubin levels at the time of sample acquisition and were compared to matched control groups 1, 2, and 3, respectively.

RESULTS

A total of 102 fecal samples from 8 cases and 10 controls were analyzed. Precholestasis samples were more abundant in phylum Firmicutes and genus Staphylococcus, whereas control 1 was more abundant in phylum Proteobacteria and genus Escherichia-Shigella. Nonmetric multidimensional scaling ordination plots based on the taxonomic composition of early fecal samples revealed significant separation between cases and controls. On indicator species analysis, genus Bacilli was more prevalent in samples from the precholestasis group, whereas genus Escherichia-Shigella was more prevalent in control 1. With feeding advances, weaning of PN and resolution of PNAC, most differences in microbiota resolved with the exception of control 3 group being more diverse compared to the postcholestasis group.

CONCLUSIONS

Premature neonates who develop PNAC, compared to those who do not, show significantly different fecal microbiomes preceding the biochemical detection of cholestasis.

Retrospective Dual-Center Study of Parenteral Nutrition-Associated Cholestasis in Premature Neonates: 15 Years' Experience

BACKGROUND

The pathogenesis of parenteral nutrition-associated cholestasis (PNAC) has not been clarified. The objective of this study was to explore the incidence of PNAC in premature infants without surgery and to identify associated risk factors.

MATERIALS AND METHODS

Premature neonates who received parenteral nutrition (PN) at least 14 days were included in a retrospective, dual-center study. Cholestasis was diagnosed as conjugated bilirubin ≥2 mg/dL. Infants with metabolic liver disease, cyanotic congenital heart disease, congenital syphilis, hepadnaviridae infection, and those who underwent surgery were excluded. Infants were divided into 3 groups chronologically: group A (2000-2004, n = 50), group B (2005-2009, n = 283), and group C (2010-2014, n = 741). A case-controlled study was conducted by comparing infants with PNAC to those without PNAC.

RESULTS

Of 1074 premature neonates, PNAC was confirmed in 53 infants (4.93%). There were 6.8% very low birth weight (BW) infants and 20.0% extremely low BW infants who developed PNAC. The incidence of PNAC decreased slightly during 2000-2014 (8.0%, 6.4%, and 4.2% in groups A, B, and C, respectively). Compared with those without PNAC, infants with PNAC (n = 53) had significantly younger gestational age, lower BW, longer PN duration, and higher rate of sepsis. Logistic regression showed male sex, PN duration ≥43 days, and sepsis were statistically correlated with PNAC.

CONCLUSIONS

Prolonged duration (≥43 days), male sex, and sepsis are probably independent risk factors for developing PNAC in premature neonates.

Incidence and Risk Factors of Parenteral Nutrition-Associated Cholestasis in Omani Neonates: Single centre experience

OBJECTIVES

Parenteral nutrition-associated cholestasis (PNAC) is one of the most challenging complications of prolonged parenteral nutrition (PN) in neonates. There is a lack of research investigating its incidence in newborn infants in Oman and the Arab region. Therefore, this study aimed to assess the incidence of PNAC and its risk factors in Omani neonates.

METHODS

This retrospective study took place between January and April 2014. All neonates who received PN for ≥14 days during a four-year period (June 2009 to May 2013) at the neonatal intensive care unit (NICU) in Sultan Qaboos University Hospital, Muscat, Oman, were enrolled.

RESULTS

A total of 1,857 neonates were admitted to the NICU over the study period and 135 neonates (7.3%) received PN for ≥14 days. Determining the incidence of PNAC was only possible in 97 neonates; of these, 38 (39%) had PNAC. The main risk factors associated with PNAC were duration of PN, duration of enteral starvation, gastrointestinal surgeries, blood transfusions and sepsis. Neonates with PNAC had a slightly higher incidence of necrotising enterocolitis in comparison to those without PNAC.

CONCLUSION

This study found a PNAC incidence of 39% in Omani neonates. There were several significant risk factors for PNAC in Omani neonates; however, after logistic regression analysis, only total PN duration remained statistically significant. Preventive strategies should be implemented in NICUs so as to avoid future chronic liver disease in this population.

Polymorphisms of CYP51A1 from cholesterol synthesis: associations with birth weight and maternal lipid levels and impact on CYP51 protein structure

We investigated the housekeeping cytochrome P450 CYP51A1 encoding lanosterol 14α-demethylase from cholesterol synthesis that was so far not directly linked to human disorders. By direct sequencing of CYP51A1 in 188 women with spontaneous preterm delivery and 188 unrelated preterm infants (gestational age <37 weeks) we identified 22 variants where 10 are novel and rare. In infants there were two novel CYP51A1 variants where damaging effects of p.Tyr145Asp from the substrate recognition region, but not p.Asn193Asp, were predicted by PolyPhen2 and SIFT. This was confirmed by molecular modeling showing that Tyr145Asp substitution results in changed electrostatic potential of the CYP51 protein surface and lengthened distance to the heme which prevents hydrogen bonding. The CYP51 Tyr145Asp mutation is rare and thus very interesting for further structure/function relationship studies. From the 12 identified known variants rs6465348 was chosen for family based association studies due to its high minor allele frequency. Interestingly, this CYP51A1 common variant associates with small for gestational age weight in newborns (p = 0.028) and lower blood total cholesterol and low density lipoprotein cholesterol levels in mothers in 2nd trimester of pregnancy (p = 0.042 and p = 0.046 respectively). Our results indicate a new link between a cholesterol synthesis gene CYP51A1 and pregnancy pathologies.