Genetic landscape of pediatric acute liver failure of indeterminate origin

BACKGROUND AND AIMS

Pediatric acute liver failure (PALF) is a life-threatening condition. In Europe, the main causes are viral infections (12%-16%) and inherited metabolic diseases (14%-28%). Yet, in up to 50% of cases the underlying etiology remains elusive, challenging clinical management, including liver transplantation. We systematically studied indeterminate PALF cases referred for genetic evaluation by whole-exome sequencing (WES), and analyzed phenotypic and biochemical markers, and the diagnostic yield of WES in this condition.

APPROACH AND RESULTS

With this international, multicenter observational study, patients (0-18 y) with indeterminate PALF were analyzed by WES. Data on the clinical and biochemical phenotype were retrieved and systematically analyzed.

RESULTS

In total, 260 indeterminate PALF patients from 19 countries were recruited between 2011 and 2022, of whom 59 had recurrent PALF. WES established a genetic diagnosis in 37% of cases (97/260). Diagnostic yield was highest in children with PALF in the first year of life (41%), and in children with recurrent acute liver failure (64%). Thirty-six distinct disease genes were identified. Defects in NBAS (n=20), MPV17 (n=8), and DGUOK (n=7) were the most frequent findings. When categorizing, the most frequent were mitochondrial diseases (45%), disorders of vesicular trafficking (28%), and cytosolic aminoacyl-tRNA synthetase deficiencies (10%). One-third of patients had a fatal outcome. Fifty-six patients received liver transplantation.

CONCLUSIONS

This study elucidates a large contribution of genetic causes in PALF of indeterminate origin with an increasing spectrum of disease entities. The high proportion of diagnosed cases and potential treatment implications argue for exome or in future rapid genome sequencing in PALF diagnostics.

Progressive familial intrahepatic cholestasis-outcome and time to transplant after biliary diversion according to genetic subtypes

Background

Progressive familial intrahepatic cholestasis (PFIC) is a heterogeneous disease characterized by progressive cholestasis in early childhood. Surgical therapy aims at preventing bile absorption either by external or internal biliary diversion (BD). Several different genetic subtypes encode for defects in bile transport proteins, and new subtypes are being discovered ongoingly. Overall, the literature is scarce, however, accumulating evidence points to PFIC 2 having a more aggressive course and to respond less favorable to BD. With this knowledge, we aimed to retrospectively analyze the long-term outcome of PFIC 2 compared to PFIC 1 following BD in children at our center.

Methods

Clinical data and laboratory findings of all children with PFIC, who were treated and managed in our hospital between 1993 and 2022, were analyzed retrospectively.

Results

Overall, we treated 40 children with PFIC 1 (n = 10), PFIC 2 (n = 20) and PFIC 3 (n = 10). Biliary diversion was performed in 13 children (PFIC 1, n = 6 and 2, n = 7). Following BD, bile acids (BA) (p = 0.0002), cholesterol (p < 0.0001) and triglyceride (p < 0.0001) levels significantly decreased only in children with PFIC 1 but not in PFIC 2. Three out of 6 children (50%) with PFIC 1 and 4 out of 7 children (57%) with PFIC 2 required liver transplantation despite undergoing BD. On an individual case basis, BA reduction following BD predicted this outcome. Of the 10 children who had PFIC 3, none had biliary diversion and 7 (70%) required liver transplantation.

Conclusion

In our cohort, biliary diversion was effective in decreasing bile acids, cholesterol levels as well as triglycerides in the serum only in children with PFIC 1 but not PFIC 2. On an individual case level, a decrease in BA following BD predicted the need for liver transplantation.

Parents' Perceptions of the Effectiveness of Music Therapy on Their Chronically Ill Children

Chronic disease in a child, with the associated hospital stays, places considerable demands on the child and their family. The aim of this study was to investigate the parents' perceptions of the music therapy used with their child during a hospital stay and to determine whether they felt that it reduced the child's anxiety and stress generated by hospital admission. We hypothesized that the use of live music therapy from a music therapist would positively support these patients in everyday clinical practice, promote their wellbeing, and have positive impacts on their vital signs and blood pressure. Children with chronic gastroenterological and nephrological diseases included in this prospective study received live music therapy with a median duration of 41 min (range from 12 to 70 min) two to four times per week until discharged from the hospital. At the time of discharge, the parents were asked to complete a Likert-style questionnaire to evaluate the music therapy. Seven items were related to general questions about the patients and sessions, and eleven items evaluated the personal perceptions of the parents. Music therapy was conducted in 83 children, with a median age of 3 years (range from 1 month to 18 years). All parents (100%) completed the questionnaire at the time of discharge. Seventy-nine percent of the parents stated that their children were able to enjoy the music therapy sessions without being stressed. In addition, 98% of the respondents said that they were grateful for the music therapy their children received (97% fully agreed and 1% rather agreed). All parents considered music therapy to be beneficial for their child. The parents' responses reflected the view that music therapy is beneficial to patients. According to the parents, music therapy can be integrated effectively in the inpatient clinical setting and can support children with chronic illnesses during their hospital stay.

Effects of Music Therapy on Vital Signs in Children with Chronic Disease

Background: Recent research found evidence supporting music therapy for hospitalized children with chronic diseases. The aim of this study was to investigate the effect of music therapy on hospitalized children’s vital signs. Methods: In this prospective study, children with chronic gastroenterological and nephrological diseases received active or receptive music therapy two to four times a week until discharge from hospital at the pediatric special care unit (SCU) and pediatric intensive care unit (ICU). Baseline and post-therapy heart rate, oxygen saturation and blood pressure were recorded and analyzed as control values at three points on the same day when the children were alone in their patient room at rest. Results: A total of 83 children, median 3 age of years (range one month to eighteen years) received music therapy. In total, 377 music therapy sessions were treated: 200 receptive therapy (78 ICU, 122 SCU) and 177 with active therapy (0 ICU, 177 SCU). Music therapy interventions showed changes in vital signs during music therapy sessions. After music therapy, heart rates decreased by 18 beats per minute (95% confidence interval (CI), −19.4 to (−16.8)), oxygen saturation increased by 2.3% (95% CI, 2.2 to 2.5), systolic blood pressure decreased by 9.2 (95% CI, −10.6 to −7.7) and diastolic blood pressure decreased by 7.9 (95% CI, −9.6 to −6.3). When music therapy was applied at the SCU (ICU), heart rates significantly reduced by 17.9 (18.9) beats per min, oxygen saturation increased by 2.4% (2.1%) and blood pressure reduced by 9.2 (2.8) mmHg (systolic) and 7.9 (0.3) mmHg (diastolic). Almost all control values were better than directly before the intervention. However, after music therapy intervention, the children showed better values in vital signs compared to being alone in their patient room. Conclusion: Music therapy is an added value for children with kidney and liver/gastrointestinal diseases during their hospital stay.

A Retrospective Analysis of Rituximab Treatment for B Cell Depletion in Different Pediatric Indications

Background: Rituximab (RTX) is used in cancer therapy as well as in the treatment of autoimmune diseases and alloimmune responses after transplantation. It depletes the disease-causing B cells by binding to the CD (cluster of differentiation) 20 antigen. We evaluate different pediatric treatment protocols (via fixed treatment schedule, B cell- or symptom-controlled) and their therapeutic effects. Methods: Demographic information, clinical and laboratory characteristics, and special laboratory values such as immunoglobulin G (IgG), CD19 positive B cells and Epstein-Barr viral load were retrospectively analyzed in children treated with RTX between 2008 and 2016. Results: Seventy-six patients aged 1 to 19 (median 13) years were treated with 259 RTX infusions. The spectrum of diseases was very heterogeneous. RTX led to a complete depletion of the B cells. The reconstitution time varied between patients and was dependent on the application schedule (median 11.8 months). Fourteen out of 27 (52%) patients developed hypogammaglobulinaemia. The risk of IgG deficiency was 2.6 times higher in children under 4 years of age than in olderones. In the last group IgG deficiency developed in only 38% of the cases (n = 8). Recurrent and severe infections were observed each in 11/72 (15%) patients. Treatment-related reactions occurred in 24/76 (32%) cases; however, treatment had to be discontinued in only 1 case. In 16/25 (76%), the Epstein-Barr viral load dropped below the detection limit after the first RTX infusion. Conclusion: RTX is an effective and well-tolerated drug for the treatment of oncological diseases as well as autoimmune and alloimmune conditions in children. B cell depletion and reconstitution varies both intra- und interindividually, suggesting that symptom-oriented and B cell-controlled therapy may be favorable. Treatment-related reactions, IgG deficiency and infections must be taken into account.

Role of Tacrolimus C/D Ratio in the First Year After Pediatric Liver Transplantation

Background: The calcineurin inhibitor (CNI) tacrolimus (TAC) is a cornerstone agent in immunosuppressive therapy in pediatric liver transplantation (LTX). Adverse effects limit the use of CNI. In adults, calculating the individual TAC metabolism rate allows to estimate the transplant recipient's risk for therapy-associated complications. Methods: A retrospective, descriptive data analysis was performed in children who had undergone LTX in 2009-2017 and had received TAC twice daily in the first year after LTX. A weight-adjusted concentration/dose ratio (C/D ratio) was calculated [TAC trough level/(daily TAC dose/body weight)] every 3 months after LTX to estimate the average individual TAC metabolism rate. Depending on the C/D ratio, all patients were divided into two groups: fast metabolizers (FM) and slow metabolizers (SM). Clinical and laboratory parameters were analyzed as risk factors in both groups. Results: A total of 78 children (w 34, m 44, median age at LTX 2.4; 0.4-17.0 years) were enrolled in the study. FM (SM) had a mean C/D ratio of <51.83 (≥51.83) ng/ml/(mg/kg). FM were younger at the time of LTX (median age 1.7; 0.4-15.8 years) than SM (5.1, 0.4-17.0), p = 0.008. FM were more likely to have biliary atresia (20/39, 51%) compared to SM (11/39, 28%), p = 0.038, whereas SM were more likely to have progressive familial intrahepatic cholestasis (9/39, 23%) vs. in FM (1/39, 3%), p = 0.014. Epstein-Barr virus (EBV) infection occurred more frequently in FM (27/39, 69%) than SM (13/39, 33%), p = 0.002. Three FM developed post-transplant lymphoproliferative disorder. The annual change of renal function did not differ in both groups (slope FM 1.2 ± 0.6; SM 1.4 ± 0.8 ml/min/1.73 m² per year, and p = 0.841). Conclusions: Calculation of individual, weight-adjusted TAC C/D ratio is a simple, effective, and cost-efficient tool for physicians to estimate the risk of therapy-associated complications and to initiate individual preventive adjustments after pediatric LTX. Lower TAC levels are tolerable in FM, especially in the presence of EBV infection, reduced renal function, or when receiving a liver transplant in the first 2 years of life.

Case Report: Hepatic Adenoma in a Child With a Congenital Extrahepatic Portosystemic Shunt

Congenital extrahepatic portosystemic shunts (CEPS), previously also described as Abernethy malformations, are rare malformations in which the extrahepatic portal system directly communicates with the vena cava inferior, thereby bypassing the liver. A hypoplastic portal vein (PV) exists in most cases. CEPS have been associated with the development of liver nodules, ranging from mostly focal nodular hyperplasia (FNH) to hepatic adenoma (HA) and even hepatocellular carcinoma (HCC). Tumor development in CEPS may be due to changes in perfusion pressures, oxygen supply or endocrine imbalances. It is important to rule out CEPS in children with liver tumors, because resection could impede future shunt occlusion procedures, and benign masses may regress after shunt occlusion. Here, we review the case of a 9-years-old male with CEPS and hepatic nuclear Factor 1-alpha (HNF-1-alpha) inactivated HA to raise awareness of this condition and review histopathological changes in the liver of CEPS.

Mutation in ITCH Gene Can Cause Syndromic Multisystem Autoimmune Disease With Acute Liver Failure

Pediatric intractable autoimmune hepatitis is rare and may be responsible for acute liver failure. Mutations in the itchy E3 ubiquitin protein ligase (ITCH) gene (located on chromosome 20q11.22) can lead to a deficiency of the encoded protein, resulting in increased T-cell activity with lack of immune tolerance and manifestation of a complex systemic autoimmune disease. A 1-year-old girl of consanguineous parents received a liver transplant (LT) because of acute liver failure attributed to a drug-induced hypereosinophilic syndrome with positive liver-kidney-mikrosome-2 antibodies. Notable findings were syndromic features, dystrophy, short stature, psychomotor retardation, and muscular hypotonia. Later, we saw corticosteroid-sensitive rejections as well as a systemic autoimmune disease with detection of specific antibodies (de novo autoimmune hepatitis, thyroiditis with exophthalmos, diabetes mellitus type 1, and immune neutropenia). Histologically, liver cirrhosis with lobular inflammatory infiltrates, giant-cell hepatitis, and ductopenia was verified in chronic cholestasis. Shortly after a second LT, a comparable liver histology could be detected, and viral, bacterial, and mycotic infections deteriorated the general health condition. Because of refractory pancytopenia related to portal hypertension and hypersplenism, a posttransplant lymphoproliferative disorder was excluded. One year after the second LT, epidural and subdural bleeding occurred. Three months afterward, the girl died of sepsis. Postmortem, whole-exome sequencing revealed a homozygous mutation in the ITCH gene. A biallelic mutation in ITCH can cause a severe syndromic multisystem autoimmune disease with the above phenotypic characteristics and acute liver failure because of autoimmune hepatitis. This case reveals the importance of ubiquitin pathways for regulation of the immune system.

Undue Elevation of Procalcitonin in Pediatric Paracetamol Intoxication is Not Explained by Liver Cell Injury Alone

INTRODUCTION AND AIM

Procalcitonin is widely used as a biomarker to distinguish bacterial infections from other etiologies of systemic inflammation. Little is known about its value in acute liver injury resulting from intoxication with paracetamol.

MATERIAL AND METHODS

We performed a single-center retrospective analysis of the procalcitonin level, liver synthesis, liver cell damage and renal function of patients admitted with paracetamol-induced liver injury to a tertiary care children's hospital. Children with acute liver failure due to other reasons without a bacterial or fungal infection served as the control group. Twelve patients with acute paracetamol intoxication and acute liver injury were compared with 29 patients with acute liver failure.

RESULTS

The procalcitonin levels were higher in children with paracetamol intoxication than in patients with acute liver failure without paracetamol intoxication (median 24.8 (0.01-55.57) ng/mL vs. 1.36 (0.1-44.18) ng/mL; p &lt; 0.005), although their liver and kidney functions were better and the liver cell injury was similar in both groups. Outcome analysis showed a trend towards better survival without transplantation in patients with paracetamol intoxication (10/12 vs. 15/29). Within each group, procalcitonin was significantly correlated with alanine aminotransferase and aspartate aminotransferase but was not correlated with the International Normalized Ratio or paracetamol blood levels in the paracetamol group. In conclusion, paracetamol intoxication leads to a marked increase in procalcitonin serum levels, which are significantly higher than those seen in acute liver failure.

CONCLUSION

The underlying mechanism is neither caused by infection nor fully explained by liver cell death alone and remains to be determined.

[Lysosomal acid lipase deficiency (LAL-D) : Diagnostic and therapeutic options in an underdiagnosed disease]

BACKGROUND AND CLINICAL SETTING

Lysosomal acid lipase deficiency is an autosomal recessive storage disease caused by mutations in the LIPA gene. The accumulation of cholesteryl esters and triglycerides in hepatocytes lead to hepatomegaly with progressive fibrosis and liver cirrhosis. Characteristically, patients have a hepatomegaly combined with high serum levels of cholesterol, LDL-cholesterol and in some cases triglyceride, whereas HDL-cholesterol is decreased. Histologically, hepatocytes show a microvesicular steatosis with typically ballooned Kupffer cells. Even though histological morphology is typical, it is not characteristic. Therefore LAL-D is supposed to be an underdiagnosed disease with a high number of unreported cases misdiagnosed as uncharacteristic fatty liver disease (NASH, NAFLD, cryptogenic liver cirrhosis). Further, there is overlap with other storage diseases, complicating a correct diagnosis.

THERAPY

Until recently, different therapeutic options could not prevent development of liver cirrhosis. Patients with Wolman's disease have an especially rapid progression and die within the first six months of life. With the recent development of a new enzyme replacement therapy with sebelipase alfa (Kanuma ®), new therapeutic options with significant improvement of dyslipidemia and reduction of transaminases have become reality. Positive clinical results seem to have the potential to significantly raise life expectancy.

CONCLUSION

These new therapeutic options warrant an increase in awareness of LAL-D by clinicians and pathologists. Correct diagnosis of LAL-D is important for effective therapy and long-term survival.

Sequencing of FIC1, BSEP and MDR3 in a large cohort of patients with cholestasis revealed a high number of different genetic variants

BACKGROUND & AIMS

The bile salt export pump (BSEP, ABCB11), multidrug resistance protein 3 (MDR3, ABCB4) and the ATPase familial intrahepatic cholestasis 1 (FIC1, ATP8B1) mediate bile formation. This study aimed to determine the contribution of mutations and common variants in the FIC1, BSEP and MDR3 genes to cholestatic disorders of differing disease onset and severity.

METHODS

Coding exons with flanking intron regions of ATP8B1, ABCB11, and ABCB4 were sequenced in cholestatic patients with assumed genetic cause. The effects of new variants were evaluated by bioinformatic tools and 3D protein modeling.

RESULTS

In 427 patients with suspected inherited cholestasis, 149 patients carried at least one disease-causing mutation in FIC1, BSEP or MDR3, respectively. Overall, 154 different mutations were identified, of which 25 were novel. All 13 novel missense mutations were disease-causing according to bioinformatics analyses and homology modeling. Eighty-two percent of patients with at least one disease-causing mutation in either of the three genes were children. One or more common polymorphism(s) were found in FIC1 in 35.3%, BSEP in 64.3% and MDR3 in 72.6% of patients without disease-causing mutations in the respective gene. Minor allele frequencies of common polymorphisms in BSEP and MDR3 varied in our cohort compared to the general population, as described by gnomAD. However, differences in ethnic background may contribute to this effect.

CONCLUSIONS

In a large cohort of patients, 154 different variants were detected in FIC1, BSEP, and MDR3, 25 of which were novel. In our cohort, frequencies for risk alleles of BSEP (p.V444A) and MDR3 (p.I237I) polymorphisms were significantly overrepresented in patients without disease-causing mutation in the respective gene, indicating that these common variants can contribute to a cholestatic phenotype.

LAY SUMMARY

FIC1, BSEP, and MDR3 represent hepatobiliary transport proteins essential for bile formation. Genetic variants in these transporters underlie a broad spectrum of cholestatic liver diseases. To confirm a genetic contribution to the patients' phenotypes, gene sequencing of these three major cholestasis-related genes was performed in 427 patients and revealed 154 different variants of which 25 have not been previously reported in a database. In patients without a disease-causing mutation, common genetic variants were detected in a high number of cases, indicating that these common variants may contribute to cholestasis development.

[Left-Lateral Living Related Liver Donation - The Essen Experience]

Background: The international organ shortage for liver transplantation exists particularly in paediatric transplantation. Therefore left-lateral living related liver donation (LLRLD) plays a major role in this field. The aim of the present study was to analyse all procedures of LLRLD in terms of donor safety from December 2008 to October 2012 at the University Hospital of Essen, Germany. Methods: All procedures of LLRLD from December 2008 to October 2012 at the University Hospital of Essen were included in the present study. All operations were carried out via an open narrowed median longitudinal laparotomy. General donor data were analysed. Complications were recorded and classified in accordance to their relevance. Results: 35 LLRLD were performed between December 2008 and October 2012 at the University Hospital of Essen, Germany. Mean age of the donors was 31.9 (23.4-61.7) years and 60 % were female. Past medical histories of the donors showed no relevant diagnoses. Mean length of the surgical procedure was 180 (± 89) minutes. Survival rate was 100 %. Minor complications were seen in 1 of 35 patients. Laboratory data showed a peak of the transaminases on the first postoperative day which resolved during the further course. Median postoperative hospital stay was 7 (5-11) days. Conclusion: LLRLD can be performed safely for the donors after adequate donor selection. The organ pool for paediatric recipients can be expanded by this procedure at suitable transplant centres.

Endoscopic treatment of pediatric post-transplant biliary complications is safe and effective

BACKGROUND AND AIM

Biliary complications (BC) after liver transplantation (LT) are associated with significant morbidity and mortality. Incidence of BC after pediatric LT is more than 10%. In adults, treatment by endoscopic retrograde cholangiopancreaticography (ERCP) is successful. As data in pediatric patients are limited, endoscopic treatment of BC in a pediatric cohort in a German transplant center was analyzed.

METHODS

LT recipients <18 years of age who were endoscopically treated for BC at University Hospital Essen were retrospectively analyzed. Characteristics of LT, endoscopic treatment measures, clinical and endoscopic presentation of BC, and outcomes after endoscopic treatment were evaluated.

RESULTS

Seventeen patients (median age 12 years) with clinical signs of BC were treated endoscopically using ERCP. Eleven patients had received a full-size liver, and six a left-sided living-donor transplant graft. In 12 patients, the bile ducts were accessible via Vater's papilla and five patients had a bilioenteric anastomosis. Biliary sphincterotomy was done in 13 patients. Eleven patients presented with stricture of the biliary anastomosis (AST), either isolated (nine) or in combination with biliary cast syndrome (BCS) or biliary leakage (one patient each). Ischemia-type biliary lesions (ITBL) were found in two patients. Five patients suffered from BCS, either as isolated pathology (two) or in combination with AST, bile leak or ITBL. In one patient, biliary access via the major papilla was not obtainable.

CONCLUSIONS

BC in pediatric LT were treated safely and successfully in pediatric patients when the biliary tract was accessible. The most common complications were AST, BCS and ITBL.

First case studies of successful ABO-incompatible living-related liver transplantation in infants in Germany

AIM

A series study mainly from Asia suggests that ABO-incompatible (ABOi) living-related liver transplantation (LRLT) for pediatric recipients is associated with excellent short- and long-term graft and patient survival. Until now, ABOi LRLT has been rarely performed in Europe. The aim of this study was to analyze the safety and early results of an ABOi LRLT in a German high-volume pediatric liver transplant center.

METHODS

Six consecutive pediatric patients (four males and two females) were included in this prospective study from January, 2010 to January, 2013 with a median age of 13 months (range, 6-30 months) receiving ABOi LRLT and were matched with six patients receiving ABO-compatible LRLT in the same period. In the ABOi group, titers of IgG and IgM isoagglutinins against the donor's blood group were determined at day 14 before the transplantation and from day 1 to 14 after the transplantation, and then twice a week for another 8 weeks. The titer results were determined as the reciprocal number of the highest serum dilution that caused macroscopical reaction.

RESULTS

The patients receiving ABOi and those receiving ABO-compatible LRLT were comparable regarding the recipient's preoperative pediatric end-stage liver disease (PELD), age, gender, and technical aspects of transplantation. The median follow-up was 2.6 years (range, 1-4.5 years). At the time of operation, the mean body weight was 7.7 kg (range, 5.7-16 kg) in ABO-compatible LRLT recipients and 8.8 kg (range, 5.5-18 kg) in ABOi LRLT recipients. In each group, the median PELD score was 28 (range, 28-35), respectively. All recipients received tacrolimus plus mycophenolate mofetil-based standard immunosuppression and four ABOi transplanted patients received intravenous immunoglobulins at days 1, 3, and 5 after liver transplantation. Patient and graft survival in this group was 83%. One female patient died within 24 hours due to fulminant gram-negative sepsis. Another patient developed acute cellular rejection at the 8th postoperative day, which responded to steroid treatment. No further complications occurred. In the ABO-compatible group, patient survival was 100% and graft survival was 83%; one patient in this group received retransplantation after 4 days. During follow-up, two patients of the ABOi group had maximum alloantibody titers of four against the donor's blood group; all other patients had titers below four.

CONCLUSION

ABOi LRLT seems to be safe without an escalation of immunosuppression and should be considered as an additional option to timely facilitate the transplantation.

Laparoscopic button cholecystostomy for progressive familial intrahepatic cholestasis in two children

BACKGROUND

Untreated, progressive familial intrahepatic cholestasis (PFIC) results in fibrosis, cirrhosis, and liver failure. It has been shown that partial external biliary diversion (PEBD) may prevent from liver transplantation in patients without cirrhosis. The aim of this study is to present a new laparoscopic technique using a button instead of a bowel conduit for PEBD.

PATIENTS AND METHODS

Two boys with PFIC (patient 1, 17 months; patient 2, 12 years) underwent laparoscopic button cholecystostomy using a 3-trocar technique by insertion of a 14 French MIC KEY button (Kimberly-Clark Worldwide, Inc, Draper, Utah, United States) at the gallbladder fundus secured with two absorbable purse-string sutures. Beside the suitability of the procedure, end points included course of serum bile acids, total bilirubin, liver enzymes, and pruritus at a follow-up of 6 months.

RESULTS

No complications related to the operation occurred. Relieve of pruritus was achieved in both the children, due to adequate bile drainage during a follow-up period of 6 months. In patient 2, a 10-mm gallstone was removed simultaneously. In patient 1, serum bile acids decreased from 12.3 to 6.6 µmol/L and in patient 2, serum bile acids decreased from 106.3 to 2.9 µmol/L. Total bilirubin, aspartate amino transferase, alanine amino transferase, and gamma-glutamyltransferase are kept in normal ranges during follow-up. Patient's and parent's acceptance with the button was excellent.

CONCLUSION

Laparoscopic button cholecystostomy is a simple, safe, and sufficient technique for PEBD in patients with PFIC. It achieves an adequate bile flow with consecutive relief of pruritus and avoids an enteric anastomosis.

Spectrum of pathogens in native liver, bile, and blood during pediatric liver transplantation

During LTX, there may be a risk that pathogens of the native liver are released into the systemic circulation. No investigations on incidence/spectrum of pathogens in native livers have been published. We hypothesized that pathogens are found in the native liver of a large proportion of pediatric patients during LTX and investigated the microbiology of native livers. These data may help optimize antibiotic therapy. Twenty-two consecutive pediatric patients (median age 14 months, range, 5 months-15 yr) receiving LTX in our department from October 2010 to October 2011 were included in this prospective study. Tissue and bile were collected from the explanted liver and were cultivated on different media. All liver tissues were investigated using a broad-range PCR (SepsiTest(®)). In 16 patients, blood cultures were collected post-transplantation. Eleven patients (50%) had at least one pathogen detected; nine of these patients had an underlying diagnosis of biliary atresia. SepsiTest(®) was positive in seven patients. In four patients it was the only test detecting any pathogen. In detail, the positivity rate for liver tissue in all patients was 41% (n = 9); for bile 25% (n = 3); and for blood 25% (n = 4). Thirteen different pathogens (69% bacterial, 31% fungal) were isolated. A highly-sensitive broad-range PCR appears to be an effective method to detect pathogens in native livers of patients undergoing LTX. A high number and variety of microbes, including a high proportion of fungal pathogens, were detected.

Pulse oximetry is insufficient for timely diagnosis of hepatopulmonary syndrome in children with liver cirrhosis

OBJECTIVE

To prospectively investigate the prevalence of hepatopulmonary syndrome (HPS), the importance of pulse oximetry in diagnosing HPS, and the longitudinal course after liver transplantation in children with cirrhosis referred for liver transplantation.

STUDY DESIGN

Fifty-six patients aged 1-17 years (mean age, 4.6 ± 5.0 years) with liver cirrhosis were screened for HPS by hyperemic capillary blood gas (CBG) analysis and contrast-enhanced transthoracic echocardiography. Eleven patients were excluded owing to conditions that can produce cardiopulmonary dysfunction, including 5 with cystic fibrosis, 1 with pulmonary arterial hypertension, and 5 with an intracardial shunt. HPS was classified in accordance with the European Respiratory Society Task Force criteria on pulmonary-hepatic disorders. Patient groups were compared for biochemical and clinical characteristics.

RESULTS

Eighteen children (40%) with cirrhosis were intrapulmonary vasodilatation (IPVD)-positive and had a pulse oximetry oxygen saturation level >98%. Two of these patients (11%) exhibited moderate HPS with an elevated alveolar arterial oxygen gradient >15 mm Hg and PaO2 <70 mm Hg; they died before undergoing liver transplantation. The sensitivity and specificity of CBG analysis for detecting elevated alveolar arterial oxygen gradient in children with IPVD was 94% and 53%, respectively. HPS was associated with late hepatoportoenterostomy (P < .04). Liver transplantation led to resolution of HPS in all patients.

CONCLUSION

IPVD is frequent in children with liver cirrhosis (40%). Pulse oximetry is insufficient for timely HPS diagnosis. Pathological CBG analysis data indicate IPVD in the majority of cases, but are imprecise in children aged <2 years. Contrast-enhanced transthoracic echocardiography and CBG analysis are recommended for evaluation of HPS in children with cirrhosis, regardless of liver synthesis capacity and clinical chemistry data.

Diversity of disorders causing neonatal cholestasis - the experience of a tertiary pediatric center in Germany

BACKGROUND AND OBJECTIVE

Rapidly establishing the cause of neonatal cholestasis is an urgent matter. The aim of this study was to report on the prevalence and mortality of the diverse disorders causing neonatal cholestasis in an academic center in Germany.

METHODS

Clinical chemistry and cause of disease were retrospectively analyzed in 82 infants (male n = 42, 51%) that had presented with neonatal cholestasis to a tertiary medical center from January 2009 to April 2013.

RESULTS

Altogether, 19 disorders causing neonatal cholestasis were identified. Biliary atresia was the most common diagnosis (41%), followed by idiopathic cases (13%), progressive familial intrahepatic cholestasis (PFIC, 10%), cholestasis in preterm infants (10%), α1AT deficiency, Alagille syndrome, portocaval shunts, mitochondriopathy, biliary sludge (all 2%), and others. Infants with biliary atresia were diagnosed with a mean age of 62 days, they underwent Kasai portoenterostomy ~66 days after birth. The majority of these children (~70%) received surgery within 10 weeks of age and 27% before 60 days. The 2-year survival with their native liver after Kasai procedure was 12%. The time span between Kasai surgery and liver transplantation was 176 ± 73 days. Six children (7%), of whom three patients had a syndromic and one a non-syndromic biliary atresia, died prior to liver transplantation. The pre- and post-transplant mortality rate for children with biliary atresia was ~12 and ~17%, respectively.

CONCLUSION

Neonatal cholestasis is a severe threat associated with a high risk of complications in infancy and it therefore requires urgent investigation in order to initiate life saving therapy. Although in the last 20 years new causes such as the PFICs have been identified and newer diagnostic tools have been introduced into the clinical routine biliary atresia still represents the major cause.

Prevalence of hepatitis E virus infection in pediatric solid organ transplant recipients--a single-center experience

HEV infection appears to be an emerging disease in industrialized countries. The aim of this study was to evaluate the prevalence of HEV infection in pediatric solid organ transplant recipients. One hundred and twenty-four pediatric recipients of liver (n = 41) or kidney (n = 83) transplants aged between one and 18 yr were screened for anti-HEV IgG antibodies. Patients were tested for fecal HEV RNA excretion if they showed anti-HEV seropositivity. As a control group, 108 immunocompetent pediatric patients without liver disease aged between three and 18 yr were screened for anti-HEV IgG. HEV seroprevalence was 2.4% in renal Tx (2/83), 4.9% in liver Tx patients (2/41), and 3.2% overall (4/124). Three of these four patients were HEV RNA-negative. In one renal transplant patient, HEV genotype 3 RNA excretion persisted and liver enzymes were elevated, indicating chronic hepatitis. In the control group, eight patients (7.4%) were HEV IgG-positive without biochemical evidence of hepatitis. The prevalence of HEV infection in pediatric renal or liver transplant recipients is not higher compared with immunocompetent children. Chronic HEV infection with long-term carriage of the virus may develop in pediatric transplant recipients. Autochthonous HEV infection needs to be considered in uncertain cases of hepatitis in immunosuppressed as well as immunocompetent children.

Gilbert's syndrome--a frequent cause of unconjugated hyperbilirubinemia in children after orthotopic liver transplantation

Gilbert's syndrome is one major cause for unconjugated hyperbilirubinemia in healthy individuals with the prevalence being approximately 3.2-8.6%. It is caused by a mutation in the promoter region of the UGT1A1-gene with a prolonged TAA-repeat coding for the enzyme bilirubin UDP-glucuronosyltransferase (A(TA)(7) TAA allele). After OLT, Gilbert's disease of the transplanted liver can cause unconjugated hyperbilirubinemia. Therefore, we looked for the presence of A(TA)(7) TAA alleles in pediatric liver transplant recipients with unconjugated hyperbilirubinemia. Laboratory results of 106 pediatric liver transplant recipients (aged 0-17 yr) were evaluated for elevated total bilirubin over 2.0 mg/dL (conjugated bilirubin <30%). In these patients, DNA of the liver graft was extracted from paraffin-embedded liver biopsy samples formerly taken for diagnostic reasons. The DNA was analyzed for A(TA)(7) TAA alleles in the promoter region of the UGT1A1-gene. In 4 of 106 pediatric liver transplant recipients we found unconjugated hyperbilirubinemia with total bilirubin above 2.0 mg/dL (conjugated bilirubin <30%). The analysis of the promoter region of the UGT1A1-gene of the liver grafts showed three homozygous A(TA)(7) TAA alleles (homozygous Gilbert's syndrome) and one heterozygous A(TA)(7) TAA allele (heterozygous Gilbert's syndrome). This study shows that pediatric liver transplant recipients with unconjugated hyperbilirubinemia are very likely to have received a liver graft from a donor with Gilbert's syndrome.