Neonatal Cholestasis

Novel mutations in NOTCH2 gene in infants with neonatal cholestasis

One cause of neonatal cholestasis (NC) is paucity of intrahepatic bile ducts which can be associated with Alagille syndrome or non- syndromic. Alagille syndrome is caused by autosomal dominant mutations in the Notch signaling pathway ligand Jagged1 in 94% of patients and mutations in the NOTCH2 receptor in <1% of patients. This is a retrospective case series studying infants with neonatal cholestasis found to have variants of unknown significance (VOUS) in NOTCH2. Sorting intolerant from tolerant (SIFT) and polymorphism phenotyping (PolyPhen) were utilized to predict a damaging effect. Five infants with NC without other features of Alagille syndrome were found to have one copy of a VOUS in NOTCH2, predicted to be damaging by SIFT and PolyPhen. Our cases support the notion that NOTCH2 mutations may result in hypoplastic biliary system. Further characterization of these variants is important to assist with our clinical approach to NC.

Diagnostic Yield of an Algorithm for Neonatal and Infantile Cholestasis Integrating Next-Generation Sequencing

OBJECTIVE

To evaluate the performance of a diagnostic protocol for neonatal/infantile cholestasis in which the main clinical patterns steered the early use of different genetic testing strategies.

STUDY DESIGN

An observational study was conducted between 2012 and 2017 in a tertiary care setting on a prospective cohort of children with cholestasis occurring at ≤1 year of age and persisting ≥6 weeks, to measure the detection rate of underlying monogenic diseases. After the exclusion of biliary atresia, a clinically driven genetic testing was performed, entailing 3 different approaches with different wideness: confirmatory single-gene testing; focused virtual panels; and wide search through trio whole-exome sequencing.

RESULTS

We enrolled 125 children (66 female, median age 2 months); 96 (77%) patients had hypocholic stools and were evaluated rapidly to exclude biliary atresia, which was the final diagnosis in 74 (59%). Overall, 50 patients underwent genetic testing, 6 with single confirmatory gene testing, 38 through panels, and 6 with trio whole-exome sequencing because of complex phenotype. The genetic testing detection rate was 60%: the final diagnosis was Alagille syndrome in 11, progressive familial intrahepatic cholestasis type 2 in 6, alpha-1-antitrypsin deficiency in 3, and progressive familial intrahepatic cholestasis type 3 in 2; a further 7 genetic conditions were identified in 1 child each. Overall, only 18 of 125 (14%) remained with an indeterminate etiology.

CONCLUSIONS

This protocol combining clinical and genetic assessment proved to be an effective diagnostic tool for neonatal/infantile cholestasis, identifying inherited disorders with a high detection rate. It also could allow a noninvasive diagnosis in children presenting with colored stools.

Multi-component lipid emulsion vs soy-based lipid emulsion for very low birth weight preterm neonates: A pre-post comparative study

OBJECTIVE

To examine the effectiveness of soybean oil-medium chain triglycerides-olive oil-fish oil lipid emulsion (SMOF-LE) on clinical outcomes of very-low-birth-weight neonates.

STUDY DESIGN

We conducted a pre-post comparative study of very-low-birth-weight neonates, dividing them according to lipid emulsion received: Intralipid (soy-based; n = 680) or SMOF-LE (n = 617). Primary outcomes were mortality, chronic lung disease, severe retinopathy, infection, and necrotising enterocolitis. Secondary outcomes were cholestasis, osteopenia, time to full feeds, and time to regain birthweight.

RESULTS

Baseline characteristics between groups were comparable. Primary outcomes did not differ significantly between groups, although any retinopathy was significantly lower in the SMOF-LE group. SMOF-LE group had lower odds of cholestasis, osteopenia, and lipid interruption, and reduced times to full feeds and to regain birthweight.

CONCLUSIONS

Compared with Intralipid, SMOF-LE was not associated with differences in mortality and major morbidities but was associated with lower odds of any retinopathy, cholestasis, and osteopenia; and improved lipid tolerance.

Neonatal cholestasis: emerging molecular diagnostics and potential novel therapeutics

Neonatal cholestasis is a group of rare disorders of impaired bile flow characterized by conjugated hyperbilirubinaemia in the newborn and young infant. Neonatal cholestasis is never physiological but rather is a sign of hepatobiliary and/or metabolic disorders, some of which might be fatal if not identified and treated rapidly. A step-wise timely evaluation is essential to quickly identify those causes amenable to treatment and to offer accurate prognosis. The aetiology of neonatal cholestasis now includes an expanding group of molecularly defined entities with overlapping clinical presentations. In the past two decades, our understanding of the molecular basis of many of these cholestatic diseases has improved markedly. Simultaneous next-generation sequencing for multiple genes and whole-exome or whole-genome sequencing now enable rapid and affordable molecular diagnosis for many of these disorders that cannot be directly diagnosed from standard blood tests or liver biopsy. Unfortunately, despite these advances, the aetiology and optimal therapeutic approach of the most common of these disorders, biliary atresia, remain unclear. The goals of this Review are to discuss the aetiologies, algorithms for evaluation and current and emerging therapeutic options for neonatal cholestasis.

New-generation fish oil and olive oil lipid for prevention of oxidative damage in preterm infants: Single center clinical trial at university hospital in Turkey

BACKGROUND

Parenteral nutrition (PN) has been widely used in preterm infants. The lipid solutions used for PN, however, are associated with oxidative stress and morbidity. The aim of this study was to compare the effectiveness of a new-generation lipid emulsion (SMOFLipid) and olive-oil based lipid emulsion for prevention of PN-associated oxidative damage.

METHODS

Preterm infants < 32 weeks of gestational age were included in this prospective randomized study. All infants were randomized to SMOFlipid or olive-oil based lipid emulsion (ClinOleic). Lipid peroxidation products were evaluated in all infants. In addition, total antioxidant capacity (TAC), and both pro- and anti-inflammatory cytokines were studied at days 0, 7 and 14.

RESULTS

A total of 89 infants (SMOFlipid, n = 42; ClinOleic, n = 47) were enrolled. TAC was higher in the SMOFlipid group compared with the ClinOleic group at all time points, and the difference on day 7 was statistically significant. Although the anti-inflammatory cytokine interleukin-10 was higher in the SMOFlipid group, this difference was not significant. Bronchopulmonary dysplasia (BPD) was lower in the SMOFlipid group (14.1%) than in the ClinOleic group (31.2%), but this finding was non-significant p > 0.05. The rate of severe BPD was significantly lower in the SMOFlipid group.

CONCLUSION

To our best of knowledge, this is the first study to suggest that SMOFlipid might decrease oxidative damage and oxidative-stress-associated morbidity compared with olive oil-based emulsion in preterm infants.

Serum ferritin in neonatal cholestasis: A specific and active molecule or a non-specific bystander marker?

BACKGROUND

Serum ferritin (SF) and consequently hepatic iron have long been considered important in liver fibrosis progression. They have been studied in different liver diseases with no previous reports in neonatal cholestasis (NC). This study aimed to measure SF in different etiologies of NC and investigate its relation to hepatic iron and fibrosis.

METHODS

SF was measured in 75 infants, including 50 with NC and 25 with sepsis. SF was compared between these two groups. Biochemical parameters, hepatic iron grades, and liver fibrosis and other histopathological characteristics and correlated with SF were assessed in NC group. Finally, a comparison between intrahepatic cholestasis and obstructive etiology was performed.

RESULTS

SF was elevated in NC (1598 ± 2405 ng/mL) with no significant difference from those with sepsis (P = 0.445). NC and sepsis constituted augmenting factors leading to more elevation of SF (2589 ± 3511 ng/mL). SF was significantly correlated with hepatic iron grades (r = 0.536, P < 0.0001) and a cut-off value of 803.5 ng/mL can predict higher grades (≥ grade 3) of iron deposition with sensitivity of 100%, specificity of 70% and accuracy of 85%. Moreover, SF was significantly higher (P < 0.0001) in those with intrahepatic cholestasis (2602 ± 3154 ng/mL) and their prevalent pathological findings of giant cell transformation (P = 0.009) and hepatocyte swelling (P = 0.023) than those with obstructive etiology (672 ± 566 ng/mL) and their prevalent pathological findings of ductular proliferation (P = 0.003) and bile plugs (P = 0.002). SF was unrelated to the grade of liver fibrosis (P = 0.058).

CONCLUSIONS

SF is non-specifically elevated in NC, with positive correlation to hepatic iron grades. SF ≥ 803.5 ng/mL can predict higher grades (≥ grade 3) of hepatic iron. However, an active role of increased SF and hepatic iron in disease progression remains questionable.

Cholestasis affects enteral tolerance and prospective weight gain in the NICU

BACKGROUND

Intestinal Failure-Associated Liver Disease is characterized by cholestasis and hepatic dysfunction due to parenteral nutrition (PN) therapy. We described key features of cholestatic infants receiving PN to assess overall outcomes in this population at our institution.

METHODS

This is a retrospective single center study of 163 neonates grouped into cholestatic (n = 63) and non-cholestatic (n = 100) as defined by peak conjugated bilirubin of ≥2.0 mg/dL or < 0.8 mg/dL, respectively. Univariate and multiple regression models were used to study associations between variables and outcomes of interest.

RESULTS

Lower Apgar scores (4 ± 3 vs. 6 ± 3, p-value = <0.005 at 1 min; 6 ± 2 vs. 7 ± 2, p < 0.005 at 5 min) and lower birth weight (adj β [SE] = 0.62 [0.27], p-value = 0.024) were risk factors for developing cholestasis. Cholestatic infants were more likely to have had gastrointestinal surgery (31 [49%] vs. 15 [15%], p-value <0.005), received PN for a longer duration (40 ± 39 days vs. 11 ± 7 days, p-value <0.005), and started enteral feeds later in life (86 ± 23 days vs. 79 ± 20 days, p-value <0.005) when compared to non-cholestatic infants. Weight percentiles in cholestatic infants were lower both at hospital discharge (14 ± 19 vs. 24 ± 22, p-value <0.005) and at 6 months of age (24 ± 28 vs. 36 ± 31, p-value = 0.05).

CONCLUSIONS

Cholestasis in the NICU is a multifactorial process, but it has a long lasting effect on prospective weight gain in infants who receive PN in the NICU. This finding highlights the importance of follow-up for adequate growth and the potential benefit from aggressive nutritional support.

Hyporegenerative anemia and other complications of rhesus hemolytic disease: to treat or not to treat is the question

Rhesus hemolytic disease of the newborn is rarely found after the implementation of anti-D immunoglobulin prophylaxis. However, it may lead to cholestasis, elevated liver transaminases, iron overload and late hyporegenerative anemia when it occurs. Etiology of this type of anemia is not defined yet and treatment is controversial. It is typically recognized after two weeks of life which is characterized by low hemoglobin and reticulocyte count. We have reported a case of a neonate with Rh hemolytic disease with late hyporegenerative anemia that was noted at day 18 of life. We treated this anemia by erythropoietin (EPO) 250 U/kg three times per week. Two weeks after initiation of erythropoietin treatment, a stable hemoglobin was noted along with an increased reticulocyte count. The patient required one further blood transfusion in the third week of therapy. Other associated findings were self-limited. A year of follow-up showed an appropriate development for age.

Neonatal Cholestasis: A Pandora's Box

Neonatal cholestasis (NC) is a diagnostic dilemma frequently countered in a neonatal care unit. Early diagnosis is vital for achieving an optimal patient outcome as many causes of cholestasis such as biliary atresia are time-sensitive and amenable to treatment if analyzed and treated early. Nonetheless, it is not generally simple to analyze these cases right on time as some of them are regularly missed due to the presence of pigmented stools, lack of newborn metabolic screening, and named as instances of prolonged jaundice. In this manner, we prescribe to explore all reasons for prolonged jaundice stretching out past 14 days in neonates. Besides, we suggest that stool card ought to be a piece of release rundown for all newborn children being released from the nursery. This is of most extreme significance in the nation like India where guaranteeing customary follow-up is as yet a tough assignment. These stool cards will help in the early determination of patients with NC particularly biliary atresia and guarantee their auspicious cure. Another reason which needs exceptional say is parenteral nutrition–associated liver illness, as the proportion of preterm babies is getting greater and greater with better neonatal care. These extreme preterm infants are in the requirement for prolonged (>14 days) total parenteral nourishment because of which they are at high hazard for NC contrasted with their more developed peers. In this survey, we will give an understanding of clinical approach, differential diagnosis, and clinical review of NC.

Case Study: Cystic Fibrosis in the Newborn

Cystic fibrosis (CF) is considered one of the most commonly occurring fatal genetic disorders. This disorder is associated with pancreatic insufficiency and pulmonary complications. However, at birth the initial complications are associated with bowel obstruction. Cystic fibrosis management warrants an interdisciplinary team because this disorder affects various organ systems. Effective management of the newborn with CF assists in improving the child's overall prognosis. Family support is critical throughout the prenatal and postnatal periods. The case presented reviews a child born with suspected CF and the clinical course within the NICU.

Identification of novel loci for pediatric cholestatic liver disease defined by KIF12, PPM1F, USP53, LSR, and WDR83OS pathogenic variants

PURPOSE

Genetic testing in pediatric cholestasis can be very informative but genetic causes have not been fully characterized.

METHODS

Exome sequencing and positional mapping in seven families with cholestatic liver disease and negative clinical testing for known disease genes.

RESULTS

KIF12, which encodes a microtubule motor protein with a tentative role in cell polarity, was found to harbor three homozygous likely deleterious variants in three families with sclerosing cholangitis. KIF12 expression is dependent on HNF-1β, deficiency which is known to cause bile duct dysmorphogenesis associated with loss of KIF12 expression. In another extended family, we mapped an apparently novel syndrome of sclerosing cholangitis, short stature, hypothyroidism, and abnormal tongue pigmentation in two cousins to a homozygous variant in PPM1F (POPX2), a regulator of kinesin-mediated ciliary transport. In the fifth family, a syndrome of normal gamma glutamyltransferase (GGT) cholestasis and hearing loss was found to segregate with a homozygous truncating variant in USP53, which encodes an interactor with TJP2. In the sixth family, we mapped a novel syndrome of transient neonatal cholestasis, intellectual disability, and short stature to a homozygous variant in LSR, an important regulator of liver development. In the last family of three affected siblings, a novel syndrome of intractable itching, hypercholanemia, short stature, and intellectual disability was mapped to a single locus that contains a homozygous truncating variant in WDR83OS (C19orf56), known to interact with ATP13A2 and BSEP.

CONCLUSION

Our results expand the genetic heterogeneity of pediatric cholestatic liver disease and highlight the vulnerability of bile homeostasis to a wide range of molecular perturbations.

Congenital intrahepatic portosystemic shunts: a potential cause for early-onset neonatal cholestasis

Cholestasis in the first days of life is uncommon in neonates. Neonatal cholestasis is usually associated with shock, sepsis, alloimmunity, metabolic disorders or biliary obstruction. A congenital intrahepatic portosystemic shunt results from failed involution of primordial liver vessels during the first days of life. Resulting shunts can lead to hepatic encephalopathy or liver tumors. A congenital intrahepatic portosystemic shunt should be considered when an alternative explanation cannot be found. In most cases, congenital intrahepatic portosystemic shunts will involute spontaneously by 1–2 years of age; however, surgical or radiologic closure may be needed.

Case Report: Severe Plasmodium vivax Malaria Mimicking Sepsis in a Neonate

Severe congenital malaria associated with Plasmodium vivax is uncommon. In Indonesia, most congenital malaria cases are due to Plasmodium falciparum infections. Most cases of congenital or neonatal malaria in endemic areas are diagnosed from peripheral smear as part of routine sepsis workup. Differentiating congenital and acquired neonatal malaria is very difficult. The case presented in this study describes severe P. vivax malaria with cholestatic jaundice and sepsis-like signs and symptoms in neonates. The mother was asymptomatic and the neonate was successfully treated with intravenous artesunate. Severe P. vivax malaria with cholestatic jaundice in neonates is an uncommon condition that should be included in the differential diagnosis of infants displaying hemolytic anemia, thrombocytopenia, cholestatic jaundice, and hepatosplenomegaly in malaria-endemic zones. Early diagnosis can prevent the use of unnecessary antibiotics and mortality of neonates.

MRI-based decision tree model for diagnosis of biliary atresia

OBJECTIVES

To evaluate MRI findings and to generate a decision tree model for diagnosis of biliary atresia (BA) in infants with jaundice.

METHODS

We retrospectively reviewed features of MRI and ultrasonography (US) performed in infants with jaundice between January 2009 and June 2016 under approval of the institutional review board, including the maximum diameter of periportal signal change on MRI (MR triangular cord thickness, MR-TCT) or US (US-TCT), visibility of common bile duct (CBD) and abnormality of gallbladder (GB). Hepatic subcapsular flow was reviewed on Doppler US. We performed conditional inference tree analysis using MRI findings to generate a decision tree model.

RESULTS

A total of 208 infants were included, 112 in the BA group and 96 in the non-BA group. Mean age at the time of MRI was 58.7 ± 36.6 days. Visibility of CBD, abnormality of GB and MR-TCT were good discriminators for the diagnosis of BA and the MRI-based decision tree using these findings with MR-TCT cut-off 5.1 mm showed 97.3 % sensitivity, 94.8 % specificity and 96.2 % accuracy.

CONCLUSIONS

MRI-based decision tree model reliably differentiates BA in infants with jaundice. MRI can be an objective imaging modality for the diagnosis of BA.

KEY POINTS

• MRI-based decision tree model reliably differentiates biliary atresia in neonatal cholestasis. • Common bile duct, gallbladder and periportal signal changes are the discriminators. • MRI has comparable performance to ultrasonography for diagnosis of biliary atresia.

Direct hyperbilirubinemia in infants with congenital heart disease

BACKGROUND

The association between congenital heart disease (CHD) and infantile cholestasis, a key finding for the diagnosis of biliary atresia (BA), has not been previously investigated. The aim of this study was therefore to investigate the characteristics of direct hyperbilirubinemia (D-HB) in infants with CHD.

METHODS

All neonates admitted to the present hospital and diagnosed with CHD in 2015 and 2016 were included. D-HB (direct bilirubin ≥ 2.0 mg/dL) at ≤60 days of age and other clinical parameters were retrospectively reviewed. Statistical analysis according to presence of D-HB was performed using chi-squared test or Wilcoxon rank sum test.

RESULTS

Seventy-six patients (M:F, 36:40) were included in this study. CHD consisted of ventricular septal defect in 17, patent ductus arteriosus in 10, and other in 49. Thirteen patients (17.1%) had D-HB at ≤60 days of age. Resolution of D-HB (DB < 2.0 mg/dL) occurred in 10 of the 13 patients during the hospital stay, and this occurred in ≤7 days in eight of the 10 patients. Sex, gestational age, birthweight, chromosomal anomalies, need for Fontan operation for CHD repair, and/or cardiac operation were not associated with D-HB at ≤60 days of age.

CONCLUSION

While D-HB was frequently observed in infants with CHD, the majority of D-HB cases resolved spontaneously in ≤1 week. Neonatal clinical parameters or CHD status was not predictive of D-HB. D-HB lasting >1 week in infants with CHD should be evaluated for the cause.

Parameters that help to differentiate biliary atresia from other diseases

BACKGROUND

The diagnosis of biliary atresia (BA) is still challenging. The aim of this study was to analyze the clinical features and parameters that contribute to a diagnosis of BA.

METHODS

From January 2000 to December 2013, 37 patients who underwent operative cholangiography were evaluated retrospectively. The patients were divided into two groups: a BA group, and a group with other cholestatic diseases (non-BA group). The demographic data and preoperative liver function test results were analyzed.

RESULTS

Of the 37 patients, 29 patients were confirmed to have BA. Age at operation was not significantly different between the two groups (P = 0.77). On preoperative liver function tests, only the level of γ-glutamyl transpeptidase (γ-GTP) was significantly higher in the BA group (P = 0.015). The predominant non-BA disease was inspissated bile syndrome (IBS). In the IBS patients, the jaundice was relieved after lavage of the biliary tree.

CONCLUSION

The preoperative differentiation of cholestasis is difficult based on laboratory data and imaging. Preoperative γ-GTP may be useful for diagnosing BA, but operative cholangiography should be performed when BA is suspected and cannot be ruled out by other methods, given that the most common non-BA disease may be IBS.

[NISCH syndrome, a rare cause of neonatal cholestasis: A case report]

NISCH syndrome is a rare autosomal recessive disease. It is characterized by scalp hypotrichosis, scarring alopecia, ichthyosis, and neonatal sclerosing cholangitis. It is caused by mutations in the CLDN1 gene encoding the claudin-1 protein, which is located at tight junctions. Fifteen cases have been reported to date and three different mutations have been identified. We report on the case of a 2-year-old boy from a consanguineous Moroccan family, presenting with NISCH syndrome and carrying the so-called Moroccan homozygous mutation (c.200-201delTT). The patient presented with the characteristic symptoms of the syndrome and a favorable progression with normalization of hepatic analyses under symptomatic treatment (vitamin supplementation and ursodeoxycholic acid). The currently limited availability of clinical and therapeutic data does not allow accurate prediction of the course of the disease and short- and long-term prognosis. Moreover, substantial interindividual variability has been reported. Description of new cases will provide new insights into the understanding and the overall management of this syndrome, the course of which remains elusive.

Management options for cholestatic liver disease in children

Due to a peculiar age-dependent increased susceptibility, neonatal cholestasis affects the liver of approximately 1 in every 2500 term infants. A high index of suspicion is the key to an early diagnosis, and to implement timely, often life-saving treatments. Even when specific treatment is not available or curative, prompt medical management and optimization of nutrition are of paramount importance to survival and avoidance of complications. Areas covered: The present article will prominently focus on a series of newer diagnostic and therapeutic options of cholestasis in neonates and infants blended with consolidated established paradigms. The overview of strategies for the management reported here is based on a systematic literature search published in English using accessible databases (PubMed, MEDLINE) with the keywords biliary atresia, choleretics and neonatal cholestasis. References lists from retrieved articles were also reviewed. Expert commentary: A large number of uncommon and rare hepatobiliary disorders may present with cholestasis during the neonatal and infantile period. Potentially life-saving disease-specific pharmacological and surgical therapeutic approaches are currently available. Advances in hepatobiliary transport mechanisms have started clarifying fundamental aspects of inherited and acquired cholestasis, laying the foundation for the development of possibly more effective specific therapies.

Early Diagnosis of ABCB11 Spectrum Liver Disorders by Next Generation Sequencing

PURPOSE

The goal of this study was the early diagnosis of ABCB11 spectrum liver disorders, especially those focused on benign recurrent intrahepatic cholestasis and progressive familial intrahepatic cholestasis.

METHODS

Fifty patients presenting neonatal cholestasis were evaluated to identify underlying etiologies. Genetic analysis was performed on patients suspected to have syndromic diseases or ABCB11 spectrum liver disorders. Two families with proven ABCB11 spectrum liver disorders were subjected to genetic analyses to confirm the diagnosis and were provided genetic counseling. Whole exome sequencing and Sanger sequencing were performed on the patients and the family members.

RESULTS

Idiopathic or viral hepatitis was diagnosed in 34%, metabolic disease in 20%, total parenteral nutrition induced cholestasis in 16%, extrahepatic biliary atresia in 14%, genetic disease in 10%, neonatal lupus in 2%, congenital syphilis in 2%, and choledochal cyst in 2% of the patients. The patient with progressive familial intrahepatic cholestasis had novel heterozygous mutations of ABCB11 c.11C>G (p.Ser4^*) and c.1543A>G (p.Asn515Asp). The patient with benign recurrent intrahepatic cholestasis had homozygous mutations of ABCB11 c.1331T>C (p.Val444Ala) and heterozygous, c.3084A>G (p.Ala1028Ala). Genetic confirmation of ABCB11 spectrum liver disorder led to early liver transplantation in the progressive familial intrahepatic cholestasis patient. In addition, the atypically severe benign recurrent intrahepatic cholestasis patient was able to avoid unnecessary liver transplantation after genetic analysis.

CONCLUSION

ABCB11 spectrum liver disorders can be clinically indistinguishable as they share similar characteristics related to acute episodes. A comprehensive genetic analysis will facilitate optimal diagnosis and treatment.

Using zebrafish to model liver diseases-Where do we stand?

Purpose of Review

The liver is the largest internal organ and performs both exocrine and endocrine function that is necessary for survival. Liver failure is among the leading causes of death and represents a major global health burden. Liver transplantation is the only effective treatment for end-stage liver diseases. Animal models advance our understanding of liver disease etiology and hold promise for the development of alternative therapies. Zebrafish has become an increasingly popular system for modeling liver diseases and complements the rodent models.

Recent Findings

The zebrafish liver contains main cell types that are found in mammalian liver and exhibits similar pathogenic responses to environmental insults and genetic mutations. Zebrafish have been used to model neonatal cholestasis, cholangiopathies, such as polycystic liver disease, alcoholic liver disease, and non-alcoholic fatty liver disease. It also provides a unique opportunity to study the plasticity of liver parenchymal cells during regeneration.

Summary

In this review, we summarize the recent work of building zebrafish models of liver diseases. We highlight how these studies have brought new knowledge of disease mechanisms. We also discuss the advantages and challenges of using zebrafish to model liver diseases.

Defects in myosin VB are associated with a spectrum of previously undiagnosed low γ-glutamyltransferase cholestasis

Hereditary cholestasis in childhood and infancy with normal serum gamma-glutamyltransferase (GGT) activity is linked to several genes. Many patients, however, remain genetically undiagnosed. Defects in myosin VB (MYO5B; encoded by MYO5B) cause microvillus inclusion disease (MVID; MIM251850) with recurrent watery diarrhea. Cholestasis, reported as an atypical presentation in MVID, has been considered a side effect of parenteral alimentation. Here, however, we report on 10 patients who experienced cholestasis associated with biallelic, or suspected biallelic, mutations in MYO5B and who had neither recurrent diarrhea nor received parenteral alimentation. Seven of them are from two study cohorts, together comprising 31 undiagnosed low-GGT cholestasis patients; 3 are sporadic. Cholestasis in 2 patients was progressive, in 3 recurrent, in 2 transient, and in 3 uncategorized because of insufficient follow-up. Liver biopsy specimens revealed giant-cell change of hepatocytes and intralobular cholestasis with abnormal distribution of bile salt export pump (BSEP) at canaliculi, as well as coarse granular dislocation of MYO5B. Mass spectrometry of plasma demonstrated increased total bile acids, primary bile acids, and conjugated bile acids, with decreased free bile acids, similar to changes in BSEP-deficient patients. Literature review revealed that patients with biallelic mutations predicted to eliminate MYO5B expression were more frequent in typical MVID than in isolated-cholestasis patients (11 of 38 vs. 0 of 13).

CONCLUSION

MYO5B deficiency may underlie 20% of previously undiagnosed low-GGT cholestasis. MYO5B deficiency appears to impair targeting of BSEP to the canalicular membrane with hampered bile acid excretion, resulting in a spectrum of cholestasis without diarrhea. (Hepatology 2017;65:1655-1669).

Neonatal cholestasis due to primary sclerosing cholangitis

Neonatal cholestasis is rarely caused due to primary sclerosing cholangitis, which is an inflammatory disease of the bile ducts, which results in obstructive fibrosis of the ducts. A 7-month-old male child presented with jaundice along with high-colored urine and clay-colored stools since birth. Liver biopsy showed mild bile duct proliferation with cholangioles showing bile and thrombi suggestive of primary sclerosing cholangitis.

Genetic profiling of children with advanced cholestatic liver disease

Advanced cholestatic liver disease is a leading referral to pediatric liver transplant centers. Recent advances in the genetic classification of this group of disorders promise a highly personalized management although the genetic heterogeneity also poses a diagnostic challenge. Using a next-generation sequencing-based multi-gene panel, we performed retrospective analysis of 98 pediatric patients who presented with advanced cholestatic liver disease. A likely causal mutation was identified in the majority (61%), spanning many genes including ones that have only rarely been reported to cause cholestatic liver disease, e.g. TJP2 and VIPAS39. We find no evidence to support mono-allelic phenotypic expression in the carrier parents despite the severe nature of the respective mutations, and no evidence of oligogenicity. The high-carrier frequency of the founder mutations identified in our cohort (1 in 87) suggests a minimum incidence of 1:7246, an alarmingly high disease burden that calls for the primary prevention through carrier screening.

Clinical practices among healthcare professionals concerning neonatal jaundice and pale stools

Jaundice and pale stools are major indicators of neonatal liver disease. Prognosis depends on timely diagnosis and management. We evaluated the clinical practices among healthcare professionals concerning jaundiced newborns and their ability to recognize pale stools. We supplied a questionnaire and a panel with eight photographs of stools, both locally validated, to physicians and nurses of the National Healthcare Service. Analysis was conducted according to professional status, specialization and years of experience of professionals and level of healthcare. Questionnaires were administered to 266 participants (100 physicians, 166 nurses). The decision to send patients to medical observation depended on the intensity of jaundice for a significant percentage of nurses. Concerning jaundiced newborns breastfed and otherwise healthy, 28.9% of physicians would never request a conjugated bilirubin assay, and only 43.3% would request it after 14 days old; for those with other signs/symptoms of disease, only 69.1% of physicians would request it immediately. Multiple linear regression analysis identified specialization as an independent variable significantly associated with the ability to recognize pale stools.

CONCLUSION

A significant percentage of healthcare professionals assumed clinical practices that preclude the timely recognition of cholestasis/pale stools, reinforcing the idea of educational needs. Specialization, rather than years of experience of professionals, was associated with better skills and practices. What is Known: • Neonatal cholestasis is a condition with some rare underlying entities having high mortality and morbidity. Early diagnosis is crucial to improve prognosis. Yet, many cases remain late recognized and referred. • Studies evaluating the ability of healthcare professionals to recognize neonatal cholestasis are scarce. What is New: • In this study, a significant percentage of professionals assumed clinical practices that preclude timely recognition of neonatal cholestasis and pale stools, reinforcing the idea of educational needs. • Specialization of professionals was associated with better skills and practices.

Cholestasis in Infancy

Jaundice is a key manifestation of hepatobiliary disease in all age groups. Jaundice is a common finding in the first 2 weeks after birth, occurring in 2.4% to 15% of newborns. The neonatal liver is at increased susceptibility to cholestasis, with an incidence ranging from 1 in 2,500 to 1 in 5,000 live births. Etiologies vary, but the most common is biliary atresia. In 2004, the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition published guidelines for the evaluation of cholestasis that clearly stated any infant with jaundice persisting beyond age 2 weeks (3 weeks in breast-fed infants with an otherwise normal history and physical examination) should be evaluated with a fractionated serum bilirubin level. Prompt evaluation, diagnosis, and intervention are vital to optimize timely intervention and improve clinical outcomes. This article discusses the etiology, diagnosis and evaluation of cholestatis in infants. [Pediatr Ann. 2016;45(12):e414-e419.].

Septooptic Dysplasia with an Associated Arachnoid Cyst

A 4-week-old male infant presented with hypothermia, hypoglycemia, and hyperbilirubinemia. His medical history was remarkable for hydrocephalus secondary to an arachnoid cyst, intermittent hypoglycemia, hypothermia, and poor feeding requiring nasogastric tube for nutrition. Physical exam revealed retrognathia, mild hypotonia, micropenis, and clinodactyly. Ophthalmologic exam demonstrated bilateral optic nerve hypoplasia (ONH). Laboratory data confirmed inadequate cortisol and growth hormone response to hypoglycemia, a low thyroxine level, and direct hyperbilirubinemia. Magnetic resonance imaging of the brain confirmed the known history of arachnoid cyst with hydrocephalus but also revealed anterior pituitary hypoplasia, absence of the posterior pituitary bright spot, a thin pituitary stalk, and bilateral optic nerve hypoplasia. A diagnosis of septooptic dysplasia (SOD) was made. Hormone replacement with hydrocortisone and levothyroxine was started with improvement in the infant's glycemic control, thermoregulation, feeding, and cholestasis. This case reinforces the importance of careful physical examination and laboratory review in a patient with known history of arachnoid cyst which has been previously described as an associated feature of optic nerve hypoplasia and hypopituitarism.

Molecular Genetic Dissection and Neonatal/Infantile Intrahepatic Cholestasis Using Targeted Next-Generation Sequencing

OBJECTIVES

To ascertain a molecular genetic diagnosis for subjects with neonatal/infantile intrahepatic cholestasis (NIIC) by the use of next-generation sequencing (NGS) and to perform a genotype-phenotype correlation.

STUDY DESIGN

We recruited Japanese subjects with NIIC who had no definitive molecular genetic diagnosis. We developed a diagnostic custom panel of 18 genes, and the amplicon library was sequenced via NGS. We then compared clinical data between the molecular genetically confirmed subjects with NIIC.

RESULTS

We analyzed 109 patients with NIIC ("genetic cholestasis," 31 subjects; "unknown with complications" such as prematurity, 46 subjects; "unknown without complications," 32 subjects), and a molecular genetic diagnosis was made for 28 subjects (26%). The rate of positive molecular genetic diagnosis in each category was 22 of 31 (71%) for the "genetic cholestasis" group, 2 of 46 (4.3%) for the "unknown with complications" group, and 4 of 32 (12.5%) for the "unknown without complications" group. The grouping of the molecular diagnoses in the group with genetic cholestasis was as follows: 12 with Alagille syndrome, 5 with neonatal Dubin-Johnson syndrome, 5 with neonatal intrahepatic cholestasis caused by citrin deficiency, and 6 with progressive familial intrahepatic cholestasis or benign recurrent intrahepatic cholestasis with low gamma-glutamyl transpeptidase levels. Several clinical datasets, including age of onset, direct bilirubin, and aminotransferases, were significantly different between the disorders confirmed using molecular genetic diagnosis.

CONCLUSION

Targeted NGS can be used for molecular genetic diagnosis in subjects with NIIC. Clinical diagnosis should be accordingly redefined in the view of molecular genetic findings.

Italian guidelines for the management and treatment of neonatal cholestasis

Hyperbilirubinemia is a frequent condition affecting newborns during the first two weeks of life and when it lasts more than 14 days it is defined as prolonged jaundice. This condition requires differential diagnosis between the usually benign unconjugated hyperbilirubinemia and the pathological conjugated hyperbilirubinemia, that is mainly due to neonatal cholestasis. It is important that the diagnosis of neonatal cholestasis be well-timed to optimize its management, prevent worsening of the patient’s outcome, and to avoid premature, painful, expensive, and useless tests. Unfortunately, this does not always occur and, therefore, the Task Force on Hyperbilirubinemia of the Italian Society of Neonatology presents these shared Italian guidelines for the management and treatment of neonatal cholestasis whose overall aim is to provide a useful tool for its assessment for neonatologists and family pediatricians.

Discharge planning

Hospital discharge is a time of transition for infants and families that requires oversight of common postnatal adaptations, screening tests, and establishment of necessary follow-up care. Preterm infants face additional medical problems that vary in complexity by the degree of prematurity. Infants born at lowest gestational ages are at highest risks for complicated neonatal course and adverse long-term outcomes. Successful transition from hospital to home care is essential to improved outcomes for high-risk infants.

Galactosaemia: an unusual cause of chronic bilirubin encephalopathy

Galactosaemia is a disorder of galactose metabolism in which raised levels of galactose and galactose-1-phosphate damage various organs. Although galactosaemia is a common metabolic liver disease in childhood, it is a rare cause of neonatal hyperbilirubinemia requiring intervention. We report an unusual case of neonatal galactosaemia that at presentation had features of acute bilirubin encephalopathy requiring exchange transfusion and at discharge had features of chronic bilirubin encephalopathy. This case report emphasises the need for timely suspicion and diagnosis of this disease for prevention of chronic morbidity.

Neonatal Cholestasis - Differential Diagnoses, Current Diagnostic Procedures, and Treatment

Cholestatic jaundice in early infancy is a complex diagnostic problem. Misdiagnosis of cholestasis as physiologic jaundice delays the identification of severe liver diseases. In the majority of infants, prolonged physiologic jaundice represent benign cases of breast milk jaundice, but few among them are masked and caused by neonatal cholestasis (NC) that requires a prompt diagnosis and treatment. Therefore, a prolonged neonatal jaundice, longer than 2 weeks after birth, must always be investigated because an early diagnosis is essential for appropriate management. To rapidly identify the cases with cholestatic jaundice, the conjugated bilirubin needs to be determined in any infant presenting with prolonged jaundice at 14 days of age with or without depigmented stool. Once NC is confirmed, a systematic approach is the key to reliably achieve the diagnosis in order to promptly initiate the specific, and in many cases, life-saving therapy. This strategy is most important to promptly identify and treat infants with biliary atresia, the most common cause of NC, as this requires a hepatoportoenterostomy as soon as possible. Here, we provide a detailed work-up approach including initial treatment recommendations and a clinically oriented overview of possible differential diagnoses in order to facilitate the early recognition and a timely diagnosis of cholestasis. This approach warrants a broad spectrum of diagnostic procedures and investigations including new methods that are described in this review.