Effects and efficacy of laparoscopic fundoplication in children with GERD: a prospective, multicenter study.

INTRODUCTION: Laparoscopic antireflux surgery (LARS) in children primarily aims to decrease reflux events and reduce reflux symptoms in children with therapy-resistant gastroesophageal reflux disease (GERD). The aim was to objectively assess the effect and efficacy of LARS in pediatric GERD patients and to identify parameters associated with failure of LARS. METHODS: Twenty-five children with GERD [12 males, median age 6 (2-18) years] were included prospectively. Reflux-specific questionnaires, stationary manometry, 24-h multichannel intraluminal impedance pH monitoring (MII-pH monitoring) and a 13C-labeled Na-octanoate breath test were used for clinical assessment before and 3 months after LARS. RESULTS: After LARS, three of 25 patients had persisting/recurrent reflux symptoms (one also had persistent pathological acid exposure on MII-pH monitoring). New-onset dysphagia was present in three patients after LARS. Total acid exposure time (AET) (8.5-0.8 %; p < 0.0001) and total number of reflux episodes (p < 0.001) significantly decreased and lower esophageal sphincter (LES) resting pressure significantly increased (10-24 mmHg, p < 0.0001) after LARS. LES relaxation, peristaltic contractions and gastric emptying time did not change. The total number of reflux episodes on MII-pH monitoring before LARS was a significant predictor for the effect of the procedure on reflux reduction (p < 0.0001). CONCLUSIONS: In children with therapy-resistant GERD, LARS significantly reduces reflux symptoms, total acid exposure time (AET) and number of acidic as well as weakly acidic reflux episodes. LES resting pressure increases after LARS, but esophageal function and gastric emptying are not affected. LARS showed better reflux reduction in children with a higher number of reflux episodes on preoperative MII-pH monitoring.

Genome screening by searching for shared segments: mapping a gene for benign recurrent intrahepatic cholestasis.

It is now feasible to map disease genes by screening the genome for linkage disequilibrium between the disease and marker alleles. This report presents the first application of this approach for a previously unmapped locus. A gene for benign recurrent intrahepatic cholestasis (BRIC) was mapped to chromosome 18 by searching for chromosome segments shared by only three distantly related patients. The screening results were confirmed by identifying an extended haplotype conserved between the patients. Probability calculations indicate that such segment sharing is unlikely to arise by chance. Searching the genome for segments shared by patients is a powerful empirical method for mapping disease genes. Computer simulations suggest that, in appropriate populations, the approach may be used to localize genes for common diseases.

A gene encoding a P-type ATPase mutated in two forms of hereditary cholestasis.

Cholestasis, or impaired bile flow, is an important but poorly understood manifestation of liver disease. Two clinically distinct forms of inherited cholestasis, benign recurrent intrahepatic cholestasis (BRIC) and progressive familial intrahepatic cholestasis type 1 (PFIC1), were previously mapped to 18q21. Haplotype analysis narrowed the candidate region for both diseases to the same interval of less than 1 cM, in which we identified a gene mutated in BRIC and PFIC1 patients. This gene (called FIC1) is the first identified human member of a recently described subfamily of P-type ATPases; ATP-dependent aminophospholipid transport is the previously described function of members of this subfamily. FIC1 is expressed in several epithelial tissues and, surprisingly, more strongly in small intestine than in liver. Its protein product is likely to play an essential role in enterohepatic circulation of bile acids; further characterization of FIC1 will facilitate understanding of normal bile formation and cholestasis.

Mutation-specific reporter for optimization and enrichment of prime editing.

Prime editing is a versatile genome-editing technique that shows great promise for the generation and repair of patient mutations. However, some genomic sites are difficult to edit and optimal design of prime-editing tools remains elusive. Here we present a fluorescent prime editing and enrichment reporter (fluoPEER), which can be tailored to any genomic target site. This system rapidly and faithfully ranks the efficiency of prime edit guide RNAs (pegRNAs) combined with any prime editor variant. We apply fluoPEER to instruct correction of pathogenic variants in patient cells and find that plasmid editing enriches for genomic editing up to 3-fold compared to conventional enrichment strategies. DNA repair and cell cycle-related genes are enriched in the transcriptome of edited cells. Stalling cells in the G1/S boundary increases prime editing efficiency up to 30%. Together, our results show that fluoPEER can be employed for rapid and efficient correction of patient cells, selection of gene-edited cells, and elucidation of cellular mechanisms needed for successful prime editing.

Association of the CLCA1 p.S357N variant with meconium ileus in European patients with cystic fibrosis.

In Cftr-/- mice that mostly die because of intestinal obstruction, intestinal expression of Clca3 is decreased, whereas upregulation of Clca3 results in amelioration of intestinal disease. The aim of the study was to investigate whether the p.S357N variant in CLCA1, the human orthologue of Clca3, acts as a modifier gene in a cohort of 682 European patients with cystic fibrosis (CF)-99 patients with meconium ileus. The 357SS genotype was significantly overrepresented in both patients with meconium ileus and also with a severe CFTR genotype (P = 0.009) and in p.F508del homozygotes (P = 0.002). This suggests that CLCA1 has similar important functions in CF-related intestinal obstruction in humans as in Cftr-/- mice.

Hydrolysed formula is a risk factor for vitamin K deficiency in infants with unrecognised cholestasis.

OBJECTIVES: Vitamin K deficiency (VKD) may cause life-threatening haemorrhages, especially in breast-fed infants with unrecognised cholestasis. Interestingly, hypoallergenic formulas appear overrepresented in reported cases of VKD bleeding (VKDB) in formula-fed infants. We therefore assessed whether the risk of VKD in formula-fed infants with cholestasis is associated with hypoallergenic formulas. PATIENTS AND METHODS: Infants born in the Netherlands between January 1991 and December 2006 with cholestatic jaundice due to biliary atresia (BA) or to α-1-antitrypsin deficiency (A1ATD) were identified in the Netherlands Study Group for Biliary Atresia Registry and the A1ATD registry, respectively. The relative risk (RR) of VKDB in patients with BA or A1ATD was calculated for different formula types. The influence of prior or ongoing breast-feeding on the RR of VKDB was also assessed. RESULTS: A total of 179 infants with either BA (139) or A1ATD (40) were included. One hundred eighteen infants were formula fed; 8 presented with VKD. Six of these 8 infants (75%) received hypoallergenic formula (whey-based hydrolysate in 4). One infant on whey-based hydrolysed formula presented with VKDB. Risk factor analysis revealed that infants receiving hydrolysed, especially whey-based, formula, had a strongly increased risk of VKD (RR 25.0 [6.4-97.2], P < 0.001)) compared with infants receiving regular formula. Prior or ongoing breast-feeding was not significantly associated with VKD. CONCLUSIONS: Infants with cholestasis receiving (whey-based) hydrolysed formula are at increased risk of developing VKD, compared with infants receiving regular formula. Because VKD may lead to serious haemorrhages, infants receiving whey-based hydrolysed formulas may need additional vitamin K supplementation.

The relationship between energy intake and body-growth in children with cystic fibrosis.

BACKGROUND & AIMS: Body-growth, expressed as weight- and height gain, is a strong predictor of morbidity and mortality in patients with cystic fibrosis (CF). Whether current historically based recommendations on a high-energy diet are sufficient for optimal growth is questionable. We therefore assessed the longitudinal relation between body-growth and routine energy intake in paediatric CF patients. METHODS: Included were patients with CF, aged 2-10 years of whom we obtained 969 measurements of weight and height along with dietary records, and 786 coefficient of fat absorption measurements (CFA). We described body-growth, energy intake, macronutrient intake and the long-term effect of energy intake and coefficient of fat absorption on body-growth during the 8-year follow-up period. RESULTS: Enrolled were 191 children with CF who had a compromised growth when compared to healthy children. The dietary intake was ≥110% estimated average requirement (EAR) in 47% of the measurements (457/969) and did not (fully) achieve the recommended high-energy level (110-200% EAR). Further, the intake expressed as EAR decreased with increasing age. Cross-sectionally, boys and girls with higher caloric intakes had higher weight-for-age (WFA). The caloric intake explained 18 and 6% of the variation. Further, boys with higher caloric intakes had also higher height-for-age-adjusted-for-target-height (HFA/TH) or BMI. The caloric intake explained 6 or 7% of the variation. Longitudinally, caloric intake was associated with both WFA in boys and girls, and with BMI in boys. Each 100 calories increased intake would result in a 0.01 (girls)-0.02 increase in z-score WFA and 0.03 increase in z-score BMI. We found no significant association between CFA and WFA, HFA/TH or BMI. The contribution of protein, fat and carbohydrates was not associated with WFA, nor with HFA/TH or BMI. CONCLUSION: Even at this relatively early age, a compromised growth in children with CF was found when compared to healthy children. The energy intake was below 110% EAR in 47% of the measurements, and appeared to be insufficient to prevent suboptimal body-growth over the 8-years of follow-up.

Cirrhosis associated with decreased survival and a 10-year lower median age at death of cystic fibrosis patients in the Netherlands.

BACKGROUND: Up to 10% of patients with Cystic Fibrosis develop cirrhotic CF-related liver disease with portal hypertension: CF cirrhosis (CFC). In a nationwide study, we aimed to determine the role of CFC on survival in the Netherlands between 1 and 1-2009 and1-1-2015. METHODS: We identified all CFC patients in the Netherlands, based on ultrasonographic liver nodularity and portal hypertension. A non-cirrhotic control group was obtained from the national Dutch CF patient registry. We compared groups with regards to baseline lung function and nutritional status and survival and age at death over a 6-year period. In case of death of CFC patients, the clinical reported cause was recorded. RESULTS: At baseline, we found no significant difference in lung function and nutritional status between the CFC patients (N = 95) and controls (N = 980). Both the 6-year survival rate (77 vs. 93%; P < .01) and the median age at death (27 vs. 37 years; P = .02) was significantly lower in CFC compared to controls. In the deceased CFC patients, the reported primary cause of death was pulmonary in 68% of cases, and liver failure related in 18% of cases. CONCLUSIONS: In the Netherlands, the presence of CFC is associated with a higher risk for early mortality and an approximately 10-year lower median age at death. This substantial poorer outcome of CFC patients was not reflected in a lower baseline lung function or a diminished nutritional status. However, in the case of mortality, the reported primary cause of death in CFC patients is predominantly pulmonary failure and not end-stage liver disease.

Heterozygous alpha-I antitrypsin deficiency as a co-factor in the development of chronic liver disease: a review.

Alpha-I antitrypsin (AIAT) is an acute-phase protein that is produced in liver cells. AIAT deficiency is a hereditary disease which is defined by the hepatic production of an abnormal protein that can not be released into the plasma. This leads to deficiency of plasma AIAT and subsequently to an impaired protection against proteases, resulting in pulmonary disease. Accumulation of the abnormal protein in hepatocytes can lead to liver damage. Serum level measurement, phenotyping and liver biopsy can be used for establishing the diagnosis. Homozygous AIAT deficiency can cause neonatal hepatitis; in adults end-stage liver disease, cirrhosis and hepatocellular carcinoma can develop. There are strong arguments to consider heterozygous AIAT deficiency as an important co-factor in the aetiology of chronic liver disease. Studies have shown that AIAT heterozygosity can be considered a modifier for hepatitis C virus, end-stage liver disease, cirrhosis and hepatocellular carcinoma. The accumulation of AIAT in the hepatocytes occurs more profoundly in a diseased liver, and as a consequence it affects the natural course of the liver disease. Therapeutic options include augmentation therapy (infusion of purified human plasma AIAT) in pulmonary disease; in end-stage liver disease liver transplantation is an option. For the future, other interventions such as gene therapy or strategies to inhibit polymerisation are promising.

Progress towards non-invasive diagnosis and follow-up of celiac disease in children; a prospective multicentre study to the usefulness of plasma I-FABP.

This prospective study investigates whether measurement of plasma intestinal-fatty acid binding protein (I-FABP), a sensitive marker for small intestinal epithelial damage, improves non-invasive diagnosing of celiac disease (CD), and whether I-FABP levels are useful to evaluate mucosal healing in patients on a gluten-free diet (GFD). Ninety children with elevated tTG-IgA titres and HLA-DQ2/DQ8 positivity were included (study group). Duodenal biopsies were taken, except in those fulfilling the ESPGHAN criteria. Plasma I-FABP levels and tTG-IgA titres were assessed sequentially during six months of follow-up. Eighty children with normal tTG-IgA titres served as control group. In 61/90 (67.8%) of the children in the study group an increased I-FABP level was found; in all these children CD diagnosis was confirmed. Interestingly, in 14/30 (46.7%) children with slightly elevated tTG-IgA titres (<10x upper limit of normal), an increased I-FABP level was found. In all these children the diagnosis of CD was confirmed histologically. After gluten elimination for six weeks I-FABP levels had decreased towards levels in the control group. Measurement of plasma I-FABP, in addition to tTG-IgA, EMA-IgA and HLAtyping, enables non-invasive diagnosing of CD in a substantial number of children, and might therefore be of value in the diagnostic approach of CD.

Genetics of familial intrahepatic cholestasis syndromes.

Bile acids and bile salts have essential functions in the liver and in the small intestine. Their synthesis in the liver provides a metabolic pathway for the catabolism of cholesterol and their detergent properties promote the solubilisation of essential nutrients and vitamins in the small intestine. Inherited conditions that prevent the synthesis of bile acids or their excretion cause cholestasis, or impaired bile flow. These disorders generally lead to severe human liver disease, underscoring the essential role of bile acids in metabolism. Recent advances in the elucidation of gene defects underlying familial cholestasis syndromes has greatly increased knowledge about the process of bile flow. The expression of key proteins involved in bile flow is tightly regulated by transcription factors of the nuclear hormone receptor family, which function as sensors of bile acids and cholesterol. Here we review the genetics of familial cholestasis disorders, the functions of the affected genes in bile flow, and their regulation by bile acids and cholesterol.

Impact of laparoscopic antireflux surgery on belching in pediatric GERD patients.

BACKGROUND: Laparoscopic antireflux surgery (LARS) is a well-established treatment option for children with proton pomp inhibitor (PPI)-resistant gastroesophageal reflux disease (GERD). Besides preventing reflux of gastric fluid and solid content, LARS may also impair the ability of the stomach to vent intragastric air (i.e. gastric belching) and induce gas-related complications, such as bloating and/or hyperflatulence. Furthermore, it was previously hypothesized that LARS induces a behavioral type of belching, not originating from the stomach, called supragastric belching. The aim of this study was to objectively evaluate the impact of LARS on gastric (GB) and supragastric belching (SGB) in children with GERD. METHODS: We performed a prospective, Dutch multicenter cohort study including 25 patients (12 males, median age 6 (range 2-18) years) with PPI-resistant GERD who were scheduled for LARS. Twenty-four-hour multichannel intraluminal impedance pH monitoring (MII-pH monitoring) was performed before and 3 months after fundoplication. Impedance pH tracings were analyzed for reflux episodes and GBs and SGBs. KEY RESULTS: LARS reduced acid exposure time from 8.5% (6.0-16.2%) to 0.8% (0.2-2.8%), p < 0.001. The number of GBs also significantly decreased after LARS (59 [43-77] VS 5 [2-12], p < 0.001). The number of air swallows remained unchanged after LARS. SGBs were infrequent before LARS with no change in the number of SGB observed after the procedure. Postoperative belching symptoms were associated with GBs, not with SGBs. CONCLUSION & INFERENCES: LARS significantly reduces the number of GBs in children with GERD, whereas the number of air swallows remains unchanged. Postoperative symptomatic belching is associated with GBs, but not with SGBs. These findings suggest that LARS does not induce the occurrence of SGBs in children, but longer follow-up is required.

Serum retinol levels and pulmonary function in children and adolescents with cystic fibrosis.

BACKGROUND: It has been suggested that higher serum retinol levels could have protective effects on pulmonary function (PF) in patients with cystic fibrosis (CF). However, serum retinol levels will be transiently decreased during pulmonary exacerbation. Therefore, the extent of chronic pulmonary inflammation should be included when describing the association between PF and serum retinol. We assessed the longitudinal relation between serum retinol, immunoglobulin G (IgG) and PF in paediatric CF patients. METHODS: We studied the serum retinol, IgG and forced expiratory volumes in one second (FEV(1)% pred.) of 228 CF patients during a seven-year follow up period. The cross-sectional and longitudinal relations between these variables were assessed. RESULTS: Serum retinol, with medians levels between 1.2 and 1.4 µmol/l, were relatively stable, while median serum IgG gradually increased during the age years. The FEV(1)% pred. was longitudinally inversely associated with serum IgG and age, but not with serum retinol. Each g/l increase in serum IgG level was associated with an accelerated yearly decline in FEV(1)% pred. of 0.5% (95% CI -0.8 to -0.1, p=0.008), and each year increase in age was associated with a 1.7% (95% CI -2.1 to -1.3, p=0.000) decline in FEV(1)% pred. This effect was not observed with respect to serum retinol levels (95% CI -1.9 to 2.2, p=0.570). CONCLUSIONS: In this large sample of children and adolescents with CF, we found no evidence that higher serum retinol levels had protective effects on PF.

Endemic Tyrolean infantile cirrhosis is not an allelic variant of Wilson's disease.

Recently, 138 cases of infantile cirrhosis originating in several families in the Austrian province of the Tyrol were reported. This endemic Tyrolean infantile cirrhosis (ETIC) is indistinguishable from Indian childhood cirrhosis (ICC), idiopathic copper toxicosis (ICT), and resembles the early forms of Wilson's disease (WND). It has been argued that ETIC might represent an allelic variant of the WND gene, which is a copper transporting P-type ATPase (ATP7B). Assuming that ETIC results from a founder effect, a possible role for ATP7B in ETIC was investigated by association studies and haplotype sharing. Because of its lethality, the mapping of ETIC was focused on obligate gene carriers, i.e. the patients' parents. Our data indicate that ETIC is a separate genetic entity, distinct from WND.

A deletion hybrid breakpoint map of the chromosomal region 13q14-q21 orders 19 genetic markers in 10 intervals.

A deletion hybrid breakpoint map of the chromosomal region 13q14-q21 has been constructed using 19 DNA markers and 13 cell lines with breakpoints in this chromosomal region. The cell lines define 10 distinct intervals in this region, which spans approximately 20 Mb. The markers include 6 RFLP markers, 11 microsatellites that provisionally had been mapped to the region 13q14-21, and 2 new polymorphic CA-repeats that were developed from an EMBL3 library of cell line ICD, containing 13pter-q14.3. The following order of markers was established: CEN-D13S320-(D13S118, D13S153)-RB1-D13S319-D13S25-(D13S31, D13S59, D13S133, D13S137)-D13S163-D13S119-(D13S26, D13S55)-(D13S131, D13S134, D13S135, D13S144, D13S152)-TEL.

Autosomal-recessive inheritance of benign recurrent intrahepatic cholestasis.

Benign recurrent intrahepatic cholestasis (BRIC) is a rare disorder characterized by recurrent episodes of cholestasis without permanent liver damage. Familial and sporadic cases have been described. Based on existing evidence, both autosomal-recessive and autosomal-dominant inheritance have been considered. We describe a large Dutch pedigree with 4 patients, strongly suggesting autosomal-recessive inheritance.

Unexpected lethal pulmonary hypertension in a 5-year-old girl successfully treated for biliary atresia.

There appears to be a relationship between portal and pulmonary hypertension. A 5-year-old girl treated for biliary atresia developed this combination unexpectedly and died of pulmonary hypertension. Established pulmonary hypertension has a poor prognosis, which underscores the importance of early diagnosis by regular screening.