Progressive liver, kidney, and heart degeneration in children and adults affected by TULP3 mutations.

Organ fibrosis is a shared endpoint of many diseases, yet underlying mechanisms are not well understood. Several pathways governed by the primary cilium, a sensory antenna present on most vertebrate cells, have been linked with fibrosis. Ciliopathies usually start early in life and represent a considerable disease burden. We performed massively parallel sequencing by using cohorts of genetically unsolved individuals with unexplained liver and kidney failure and correlated this with clinical, imaging, and histopathological analyses. Mechanistic studies were conducted with a vertebrate model and primary cells. We detected bi-allelic deleterious variants in TULP3, encoding a critical adaptor protein for ciliary trafficking, in a total of 15 mostly adult individuals, originating from eight unrelated families, with progressive degenerative liver fibrosis, fibrocystic kidney disease, and hypertrophic cardiomyopathy with atypical fibrotic patterns on histopathology. We recapitulated the human phenotype in adult zebrafish and confirmed disruption of critical ciliary cargo composition in several primary cell lines derived from affected individuals. Further, we show interaction between TULP3 and the nuclear deacetylase SIRT1, with roles in DNA damage repair and fibrosis, and report increased DNA damage ex vivo. Transcriptomic studies demonstrated upregulation of profibrotic pathways with gene clusters for hypertrophic cardiomyopathy and WNT and TGF-ß signaling. These findings identify variants in TULP3 as a monogenic cause for progressive degenerative disease of major organs in which affected individuals benefit from early detection and improved clinical management. Elucidation of mechanisms crucial for DNA damage repair and tissue maintenance will guide novel therapeutic avenues for this and similar genetic and non-genomic diseases.

Protocol Biopsies in Pediatric Liver Transplantation Recipients Improve Graft Histology and Personalize Immunosuppression.

OBJECTIVES: Protocol liver biopsies (PLBs) are part of the follow-up program at many pediatric liver transplant centers, but the impact on clinical decision-making and allograft histology following adjustments of immunosuppression (IS) after PLB has not been thoroughly analyzed. METHODS: Following our previous single-center cohort study, we have now evaluated histological findings of 178 PLBs of 118 pediatric patients transplanted at our center between 1998 and 2017. In particular, we focused on the changes in allograft histology in the follow-up biopsy of a subgroup of 22 patients, in which the histologic findings led to an adjustment of immunosuppressive therapy. All biopsies of this sub-study group were reevaluated by an experienced pathologist. RESULTS: The overall frequency and severity of fibrosis increased over time after orthotopic liver transplantation. Patients with donor-specific antibodies (DSAs) had a higher prevalence of fibrosis than DSA-negative patients. Graft inflammation decreased significantly after intensifying IS, but renal function needs to be monitored. A significant increase in fibrosis was detected in children with reduced IS. CONCLUSION: The adjustment of IS following PLBs has a significant impact on allograft histology. Since chronic inflammatory changes may lead to graft failure, adjustment of IS seems to be of major importance for the long-term outcome.

Liver cirrhosis in children - the role of imaging in the diagnostic pathway.

Liver cirrhosis in children is a rare disease with multifactorial causes that are distinct from those in adults. Underlying reasons include cholestatic, viral, autoimmune, hereditary, metabolic and cardiac disorders. Early detection of fibrosis is important as clinical stabilization or even reversal of fibrosis can be achieved in some disorders with adequate treatment. This article focuses on the longitudinal evaluation of children with chronic liver disease with noninvasive imaging tools, which play an important role in detecting cirrhosis, defining underlying causes, grading fibrosis and monitoring patients during follow-up. Ultrasound is the primary imaging modality and it is used in a multiparametric fashion. Magnetic resonance imaging and computed tomography are usually applied second line for refined tissue characterization, clarification of nodular lesions and full delineation of abdominal vessels, including portosystemic communications.

Outcome of liver transplantation and prevalence of liver fibrosis in Crigler-Najjar syndrome.

INTRODUCTION: Crigler-Najjar syndrome (CNS) is a rare inherited disorder that is characterized by high levels of non-hemolytic, unconjugated hyperbilirubinemia leading to brain damage and even death. Liver transplantation (LT) can correct the metabolic defect, but there are little data regarding LT in this patient cohort. The liver parenchyma has been considered to be structurally normal in CNS, but there is growing evidence of clinically silent but histologically significant fibrosis in CNS patients. PATIENTS AND METHODS: We included 13 patients in our retrospective study who underwent LT at our center. Patient survival, graft function, and long-term complications were evaluated over a median follow-up period of 10 years (range: 1-16 years). In addition, the prevalence of histologically relevant fibrosis was characterized. RESULTS: The overall survival among our LT patients was 100%. The graft survival was only 61.5%. During the follow-up period, 5 LT patients had to undergo retransplantation. More than 45% of our patients showed histological signs of fibrosis. CONCLUSION: LT remains the only definite therapeutic option for severe CNS but needs to be considered thoroughly regarding the clinical risk-benefit-ratio and impact on quality of life. Furthermore, hepatic parenchymal injury needs to be considered while evaluating future therapeutic options for CNS.

Presence of donor specific HLA class 2 antibodies (DSA class 2) is associated with development of graft fibrosis more than 10 years after liver transplantation-a retrospective single center study.

Here the impact of donor specific human leukocyte antigen (HLA) class 2 antibodies (DSA cl 2) on long term outcome after liver transplantation (LT) was investigated. Altogether 156 (44 pediatric and 112 adult) LT recipients were included in the study. Graft fibrosis was assessed by liver elastography and biopsy. DSA cl 2 were determined by Luminex technology. 46% of LT recipients were positive for DSA cl 2 after a median follow-up of 15 years. In the multivariate analysis DSA cl 2 were significantly associated with immunosuppressive monotherapy (OR 5.42; 95% CI: 1.02-28.90; p = .048). Compared to DSA cl 2 negative patients, positive recipients had significantly more graft fibrosis based on the liver stiffness (mean 9.4 ± 9.0 kPa vs. 6.5 ± 6.3 kPa; p < .002) and fibrosis stages determined by liver elastography (p = .016) and the performed liver biopsies (p = .002). Also, a significantly higher incidence of chronic rejections (11% vs. 2%; p = .045) and graft losses (6% vs. 0%; p = .043) were found. In the multivariate regression analysis DSA cl 2 were significantly associated with graft fibrosis (OR 4.57; 95% CI 1.59-13.10; p = .005). So, these data suggest that development of DSA cl 2 occurs more often with immunosuppressive monotherapy and may ultimately result in chronic rejection and graft fibrosis.

Short- and long-term results of liver transplantation according to age at transplant: a single-center experience of 351 children.

Pediatric liver transplantation (PLT) has very good results at experienced transplant centers. However, there is still an ongoing discussion about inferior outcomes, especially in young infants. The aim of this retrospective study was to evaluate outcomes of infants compared to older recipients in a single center over 20 years. We conducted a retrospective study of children who received liver transplants at our center between 1991 and 2011. Only patients without other limiting organ involvement were included and compared according to age. The inclusion criteria were fulfilled by 351 patients (173 vs. 178). The most common indication in both groups was biliary atresia (82.1% vs. 49.4%). The 1-, 5-, and 10-year patient survivals were 93.8%/91.8%/91.1% and 93%/90.8%/90.1%, and the graft survivals were 90.4%/83.5%/79.6% and 89.4%/81.8%/77.5%, respectively. Complications such as postoperative bleeding, biliary complications, or perfusion impairment occurred more often in infants. Leading indications for retransplantation (vascular complications/primary nonfunction) and leading causes of death (sepsis/multiorgan failure) were the same in both groups. Significant predictors for patient loss were decade of transplantation, retransplantation, postoperative bleeding, and infections for infants. Predictors for graft loss were bowel perforation, arterial thrombosis, and age >12 months. Children can have excellent results, independent of age at PLT.

Psychosocial situation, adherence, and utilization of video consultation in young adult long-term pediatric liver transplant recipients during COVID-19 pandemic.

BACKGROUND: Young adults who underwent liver transplantation in childhood (YALTs) are highly vulnerable to non-adherent behavior and psychosocial problems. During the COVID-19 pandemic, special efforts may be necessary to maintain contact with these patients and offer support. This can be achieved through the use of telemedicine. The study's objective was to assess adherence and the psychosocial situation of YALTs during the COVID-19 pandemic in Germany and to evaluate the utilization of video consultations. METHODS: In May 2020, a questionnaire was sent to YALTs treated at the Hamburg University Transplant Center, accompanied by the offer of video appointments with the attending physician. The questionnaire included the Generalized Anxiety Disorder Scale 7, the Patient Health Questionnaire 2, and questions compiled by the authors. RESULTS: Of 98 YALTs, 12% used the video consultation, while 65% had an in-person appointment. The 56 patients who completed the questionnaire did not report reduced medication adherence during the pandemic, but 40% missed follow-up visits with their primary care physician or check-up laboratory tests. About 70% of YALTs were afraid to visit their physician and the transplant center, and 34% were afraid of a SARS-CoV-2 infection. Mental health and well-being were unimpaired. CONCLUSIONS: During the COVID-19 pandemic, YALTs in our study did not show an increased need for psychosocial support, but a majority were afraid to attend medical appointments, and 40% reported lower appointment adherence. Acceptance of video consultations was lower than expected. The reasons for this need to be further investigated in order to optimize care.

Genotype correlates with the natural history of severe bile salt export pump deficiency.

BACKGROUND & AIMS: Mutations in ABCB11 can cause deficiency of the bile salt export pump (BSEP), leading to cholestasis and end-stage liver disease. Owing to the rarity of the disease, the associations between genotype and natural history, or outcomes following surgical biliary diversion (SBD), remain elusive. We aimed to determine these associations by assembling the largest genetically defined cohort of patients with severe BSEP deficiency to date. METHODS: This multicentre, retrospective cohort study included 264 patients with homozygous or compound heterozygous pathological ABCB11 mutations. Patients were categorized according to genotypic severity (BSEP1, BSEP2, BSEP3). The predicted residual BSEP transport function decreased with each category. RESULTS: Genotype severity was strongly associated with native liver survival (NLS, BSEP1 median 20.4 years; BSEP2, 7.0 years; BSEP3, 3.5 years; p <0.001). At 15 years of age, the proportion of patients with hepatocellular carcinoma was 4% in BSEP1, 7% in BSEP2 and 34% in BSEP3 (p = 0.001). SBD was associated with significantly increased NLS (hazard ratio 0.50; 95% CI 0.27-0.94: p = 0.03) in BSEP1 and BSEP2. A serum bile acid concentration below 102 µmol/L or a decrease of at least 75%, each shortly after SBD, reliably predicted NLS of ≥15 years following SBD (each p <0.001). CONCLUSIONS: The genotype of severe BSEP deficiency strongly predicts long-term NLS, the risk of developing hepatocellular carcinoma, and the chance that SBD will increase NLS. Serum bile acid parameters shortly after SBD can predict long-term NLS. LAY SUMMARY: This study presents data from the largest genetically defined cohort of patients with severe bile salt export pump deficiency to date. The genotype of patients with severe bile salt export pump deficiency is associated with clinical outcomes and the success of therapeutic interventions. Therefore, genotypic data should be used to guide personalized clinical care throughout childhood and adulthood in patients with this disease.

Oxalate retinopathy is irreversible despite early combined liver-kidney transplantation in primary hyperoxaluria type 1.

In primary hyperoxaluria type 1 (PH1), systemic oxalate deposition (oxalosis) in end-stage renal disease (ESRD) is associated with high morbidity and mortality, particularly in children with infantile oxalosis (IO). Combined liver and kidney transplantation (CLKT) is the only curative treatment option in these patients. After CLKT, systemic oxalosis decreases continuously, although only insufficient data are available regarding oxalate retinopathy (ROx), leading to severe visual impairment. We analyzed long-term follow-up data of ROx in 13 patients undergoing CLKT for PH1 at our center between 1998 and 2018. Age at transplantation was 1.3-14.2 years, including nine patients with IO. We performed visual acuity testing, slit lamp investigation, funduscopy, fundus photography, and spectral-domain optical coherence tomography (SD-OCT) imaging. Severe (grade 2-4) ROx was present in all nine children with IO but not in the four patients developing ESRD in adolescence. A significant negative correlation was found between age at onset of ESRD and grade of ROx (r = -0.66; P < .001). Notably, follow-up assessment after CLKT demonstrated no regression of ROx after a median of 5.3 years (range 0.6-14). The data show that despite early CLKT in IO, ROx is irreversible and the concomitant visual deterioration occurs prior to transplantation.

Surgical Aspects of Liver Transplantation and Domino Liver Transplantation in Maple Syrup Urine Disease: Analysis of 15 Donor-Recipient Pairs.

Liver transplantation (LT) has been shown to be a feasible treatment in patients with severe forms of maple syrup urine disease (MSUD). Because of a sufficient extrahepatic enzyme activity in non-MSUD individuals, the organ of MSUD patients can be used as a domino graft. We performed a retrospective data collection of all LTs for MSUD carried out at the University Medical Center Hamburg-Eppendorf (2016-2018). Moreover, data from all consecutive domino LTs of the MSUD grafts either transplanted at our institution or allocated to other transplant centers were analyzed. During the study period, 15 LTs in MSUD patients were performed (12 children, 3 adults; median age, 10.9 years; range, 0.3-26.1 years). Biliary complications occurred in 20%, and 13.3% suffered from bleeding complications. No further surgical problems occurred. At present, all MSUD patients are alive with a well-functioning liver graft and on an unrestricted diet. In total, 14 consecutive domino LTs were performed. No surgical complications requiring intervention occurred. One patient died because of HCC relapse, and all other patients are alive with good liver graft function. In conclusion, the use of MSUD livers as domino grafts is safe and allows application of LT in MSUD patients without net extraction of a liver graft from the limited donor pool.

Tissue inhibitor of metalloproteinase 1 and AST-to-Platelet Ratio Index as noninvasive biomarkers predict allograft fibrosis after pediatric liver transplantation.

BACKGROUND: Assessing liver fibrosis in patients after liver transplantation is still largely dependent on liver biopsy. Especially in children, noninvasive methods are of utmost importance. We evaluated tissue inhibitor of metalloproteinase 1 (TIMP1) and AST-to-Platelet Ratio Index (APRI) and their potential as serum biomarkers to predict liver allograft fibrosis (LAF) in a pediatric cohort. METHODS: In this retrospective, observational study, we analyzed 91 protocol liver biopsy specimens from 73 children after pediatric liver transplantation (PLT) and compared histological stage of liver fibrosis using LAF Score (LAFSc) and Ishak Score (IshakSc) to TIMP1-serum concentration and APRI using ROC analysis. RESULTS: In our cohort, TIMP1 and APRI reliably predict LAF. Depending on the histological scoring system, cutoff values for TIMP1 were 328 ng/mL (IshakSc ≥ IV) and 351 ng/mL (LAFSc ≥ 5) with AUC of 0.86 and 0.98. The cutoff for APRI was 0.8 with AUC of 0.87 (IshakSc ≥ IV) and 0.94 (LAFSc ≥ 5). Using LAFSc, TIMP1 and APRI showed excellent diagnostic accuracy to detect severe LAF (LAFSc ≥ 5) with PPV of ≥ 90% and NPV of 100%. CONCLUSION: TIMP1 and APRI are accurate biomarkers to predict severe LAF in children. The use of TIMP1 and APRI will not replace but complement liver biopsies after PLT to further improve our understanding of each individual patient.

Impact on the hepatic flow velocity after pediatric combined liver-kidney transplantation compared to isolated pediatric liver transplantation-A matched-pair analysis.

BACKGROUND: Combined liver-kidney transplantation (CLKT) in children is still a rarely performed procedure. Our aim was to analyze the effect of the simultaneous transplantation of the kidney in pediatric CLKT on the liver graft flow velocity, and vascular complications compared to singular liver transplantation (LTX) in children. METHODS: All pediatric CLKT performed at our institution from 1998 to 2016 were matched with singular LTX and retrospectively analyzed. RESULTS: Overall 30 CLKT were performed in 28 children (median age 8 years, range 1-16) and matched with 30 children undergoing singular LTX (median age 7.9 years, range 1-16). No significant differences were found concerning the systolic peak flow velocity of the hepatic artery (HA) or the resistance index (RI). Vascular complications of the hepatic vessels occurred in 16.7% (CLKT) and 6.7% (LTX). The 1-/5- and 10-year patient survival was 93.3%/93.3% and 93.3% (CLKT) and 100%/100% and 92.9% (LTX). 1-/5-and 10-year liver graft survival was 76.7%/73.2% and 73.2% (CLKT) and 84.4%/75.9% and 69.6% (LTX). CONCLUSION: The simultaneous transplantation of the kidney in CLKT had no negative impact on hepatic flow velocity or vascular complications. Frequent Doppler ultrasound examinations, accurate volume management, and avoidance of abdominal pressure might be an explanation for the results and an excellent graft- and patient survival.

Fatigue in pediatric liver transplant recipients and its impact on their quality of life.

The aim of the study was to investigate the occurrence of fatigue in 100 pediatric liver transplant recipients aged 2-18 years and its impact on their health-related quality of life (HRQL). HRQL and fatigue were measured using the PedsQL 4.0 Inventory and the PedsQL Multidimensional Fatigue Scale, which encompasses three subscales: general fatigue, sleep/rest fatigue, and cognitive fatigue. The impact of the different domains of fatigue and of clinical and sociodemographic factors on the HRQL was identified with stepwise multiple regression analyses. Parent proxy-reports were available for all 100 participants (2-18 years), and child self-reports were available for 71 patients (8-18 years). Across all domains, participants and their parents reported significantly more fatigue than healthy peers in a large PedsQL validation study. Thirty-seven percent of patients and 57% of parents scored clinically relevant levels of fatigue. In the multiple regression analyses, none of the clinical and sociodemographic factors contributed to the HRQL for child self-report. Only general and cognitive fatigue were significant predictors of patients' HRQL, explaining 66% of the variance in the PedsQL total score. For parent proxy-report, general and cognitive fatigue also significantly predicted child's HRQL. Further predictors were child's age and family income. The regression model explained 65% of the variance. These findings demonstrate the importance of assessing fatigue during regular follow-up examinations. Further research is urgently needed to better understand the underlying mechanisms of fatigue. Improvement of fatigue symptoms is essential for better HRQL, for cognitive functioning, and for school achievement.

Alloimmunity and Cholestasis After Liver Transplantation in Children With Progressive Familial Intrahepatic Cholestasis.

OBJECTIVES: Bile salt export pump (BSEP) deficiency is an important reason for chronic cholestasis leading to liver transplantation (LT) in early childhood. The underlying pathology is a dysfunction of BSEP due to various mutations in the ABCB11 gene. Cases of clinical recurrence after LT due to alloantibodies directed against BSEP (antibody-induced BSEP deficiency [AIBD]) have been reported. Most of these patients could be controlled by intensified immunosuppression. METHODS: We here report on 3 children with BSEP-deficiency and end-stage liver disease, which developed AIBD after LT refractory to extensive immunosuppressive and immunomodulatory treatments; retransplantation was necessary in all 3 patients. In 1 patient, a stem cell transplantation was performed successfully. RESULTS: AIBD seems to be induced by triggering factors such as initial impaired graft function or infections after LT. CONCLUSIONS: The underlying mutation may play a role in this process. Intensifying immunosuppression may be able to control AIBD, but some cases seem to be refractory to treatment and require retransplantation. Stem cell transplantation may provide a new therapeutic option for cases refractory to conservative treatment.

Allogeneic haematopoietic stem cell transplantation eliminates alloreactive inhibitory antibodies after liver transplantation for bile salt export pump deficiency.

Progressive familial intrahepatic cholestasis 2 is an autosomal-recessive disorder caused by mutations in the ABCB11 gene, which encodes the bile salt export pump (BSEP). Recurrence of BSEP deficiency after liver transplantation is caused by the development of anti-BSEP antibodies. Antibody-induced BSEP deficiency is typically treated by increasing immunosuppressive therapy. We report, in a child, the first case of allogeneic haematopoietic stem cell transplantation for antibody-induced BSEP deficiency that was refractory to intensive pharmacological immunosuppression and immunoadsorption. After haematopoietic stem cell transplantation, anti-BSEP antibodies were cleared from the patient's serum and later from the canalicular space of the liver graft.

Long-term follow-up after full-split liver transplantation and its applicability in the recent transplant era.

INTRODUCTION: Full-split liver transplantation (LTX) offers the possibility to expand the donor pool by utilization of one liver for two adults. The aim of our study was to analyze the long-term outcome in a large series and its applicability in the recent transplant era. METHODS: We performed a retrospective analysis of all full-split LTX from deceased donors (1999-2015). Additionally, the potential of full-split LTX was retrospectively analyzed in all whole organ LTX recipients between 2006 and 2015 (after introduction of the MELD allocation). RESULTS: We performed 44 full-split LTX, thereof 82% before introduction of the MELD-based allocation system in Germany. Analysis showed highly selected recipients (median MELD score 8 points) and organ data (median donor age 30 years). 5- and 10-year patient survival rates after full-left and full-right LTX were 90.7%/90.7% and 85.2%/56.8% (P = .301), corresponding graft survival rates were 80.5%/80.5% in full-left grafts and 73.7%/36.8% in full-right graft (P = .198). CONCLUSION: In the past, in case of strict donor and recipient selection, full-split LTX was a feasible method with a good outcome. Due to introduction of the national waiting list with a patient-oriented allocation based on the MELD score in 2006, full-split LTX seems to be not any longer applicable.

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.

Bile salt export pump-reactive antibodies form a polyclonal, multi-inhibitory response in antibody-induced bile salt export pump deficiency.

UNLABELLED: Progressive familial intrahepatic cholestasis type 2 (PFIC-2) is caused by mutations in ABCB11, encoding the bile salt export pump (BSEP). In 2009, we described a child with PFIC-2 who developed PFIC-like symptoms after orthotopic liver transplantation (OLT). BSEP-reactive antibodies were demonstrated to account for disease recurrence. Here, we characterize the nature of this antibody response in 7 more patients with antibody-induced BSEP deficiency (AIBD). Gene sequencing and immunostaining of native liver biopsies indicated absent or strongly reduced BSEP expression in all 7 PFIC-2 patients who suffered from phenotypic disease recurrence post-OLT. Immunofluorescence, western blotting analysis, and transepithelial transport assays demonstrated immunoglobulin (Ig) G-class BSEP-reactive antibodies in these patients. In all cases, the N-terminal half of BSEP was recognized, with reaction against its first extracellular loop (ECL1) in six sera. In five, antibodies reactive against the C-terminal half also were found. Only the sera recognizing ECL1 showed inhibition of transepithelial taurocholate transport. In a vesicle-based functional assay, transport inhibition by anti-BSEP antibodies binding from the cytosolic side was functionally proven as well. Within 2 hours of perfusion with antibodies purified from 1 patient, rat liver showed canalicular IgG staining that was absent after perfusion with control IgG. CONCLUSIONS: PFIC-2 patients carrying severe BSEP mutations are at risk of developing BSEP antibodies post-OLT. The antibody response is polyclonal, targeting both extra- and intracellular BSEP domains. ECL1, a unique domain of BSEP, likely is a critical target involved in transport inhibition as demonstrated in several patients with AIBD manifest as cholestasis.

Hepatic shear wave elastography in children under free-breathing and breath-hold conditions.

OBJECTIVES: To compare hepatic 2D shear wave elastography (2D SWE) in children between free-breathing and breath-hold conditions, in terms of measurement agreement and time expenditure. METHODS: A cohort of 57 children (12.7±4.3 years) who underwent standardized 2D SWE between May and October 2015 were retrospectively evaluated. Liver elastograms were obtained under free-breathing and breath-hold conditions and time expenditure was measured. Median stiffness, interquartile range (IQR), and IQR/median ratio were calculated based on 12, six, and three elastograms. Results were compared using Pearson correlation coefficient, intraclass correlation coefficient (ICC), Bland-Altman analysis, and Student's t. RESULTS: Median liver stiffness under free-breathing and breath-hold conditions correlated strongly (7.22±4.5kPa vs. 7.21±4.11kPa; r=0.97, P<0.001). Time to acquire 12 elastograms with free-breathing was lower than that with breath-holding (79.3±32.5sec vs. 143.7±51.8sec, P<0.001). Results for median liver stiffness based of 12, six, and three elastograms demonstrated very high agreement for free-breathing (ICC 0.993) and for breath-hold conditions (ICC 0.994). CONCLUSIONS: Hepatic 2D SWE performed with free-breathing yields results similar to the breath-hold condition. With a substantially lower time requirement, which can be further reduced by lowering the number of elastograms, the free-breathing technique may be suitable for infants and less cooperative children not capable of breath-holding. KEY POINTS: • Hepatic 2D SWE performed with free-breathing yields results similar to breath-hold condition. • Benefit of the free-breathing approach is the substantially lower time requirement. • Lowering the number of elastograms can further reduce time expenditure. • Free-breathing 2D SWE is suitable in children with suspected liver disease.

Health-related quality of life after combined liver and kidney transplantation in children.

While reduced HRQOL following isolated organ transplantation has been previously reported, there are no data in the context of children following CLKT. Twenty-three children who underwent CLKT at our institution were included in the study. The indication for CLKT was PH1 in 13 patients and ARPKD in 10 patients. Quantification of HRQOL was facilitated through the use of the PedsQL 4.0 Generic Core Scale. The results of the study were compared to healthy children and published data of children who had undergone LTx or KTx. The CLKT samples' child self-report showed good HRQOL. No statistically significant difference was found between the patients with PH1 and patients with ARPKD (P=.4). Compared to healthy children, a significant difference in the total scale score, the physical health score, and the school functioning was reported. HRQOL did not differ significantly when compared to patients following isolated LTx or KTx. To improve HRQOL after CLKT, a focus on patients' physical health, educational performances, and overall quality of life is crucial. Thus, coordinated medical care across disciplines and psychological and social support is essential to achieve this goal.