Taking the next step forward - Diagnosing inherited infantile cholestatic disorders with next generation sequencing.

Identifying rare genetic forms of infantile cholestasis is challenging due to their similar clinical presentation and their diverse etiology. After exclusion of common non-genetic causes a huge list of rare differential diagnosis remains to be solved. More than 90 genes are associated with monogenic forms of infantile cholestasis, thus preventing routine genetic workup by Sanger sequencing. Here we demonstrate a next generation sequencing approach to discover the underlying cause in clinically well characterized patients in whom common causes of infantile cholestasis have been excluded. After validation of the analytical sensitivity massive parallel sequencing was performed for 93 genes in six prospectively studied patients. Six novel mutations (PKHD1: p.Thr777Met, p.Tyr2260Cys; ABCB11: p.Val1112Phe, c.611+1G > A, p.Gly628Trpfs*3 and NPC1: p.Glu391Lys) and two known pathogenic mutations were detected proving our multi gene panel for infantile cholestasis to be a sensitive and specific method overcoming the complexity of the phenotype-based, candidate gene approach. Three exemplary clinical cases of infants with cholestasis are presented and discussed in the context of their genetic and histopathological findings (autosomal recessive polycystic kidney disease, atypical PFIC and Niemann-Pick syndrome type C1). These case reports highlight the critical impact of integrating clinical, histopathological and genetic data during the process of multi gene panel testing to ultimately pinpoint rare genetic diagnoses.

High levels of procalcitonin in the early phase after pediatric liver transplantation indicate poor postoperative outcome.

BACKGROUND/AIMS: To date, no data is available about procalcitonin (PCT) levels and its relevance to morbidity and graft function in the early phase after pediatric liver transplantation (pLTx). The aim of this study was to analyse the prognostic relevance of early postoperative PCT elevations in pediatric liver recipients. METHODOLOGY: Thirty pediatric patients who underwent 32 liver transplantations were included into this observational single-center study. RESULTS: Patients with high PCT levels on postoperative day (POD) 2 had higher International Normalized Ratio values on POD 5 (p<0.05) and suffered more often from primary graft non-function (p<0.05). They also had a longer stay in the pediatric intensive care unit (p<0.01) and on mechanical ventilation (p=0.001). There was no correlation between PCT elevation and systemic infection. However, PCT levels were correlated with peak serum lactate levels immediately after graft reperfusion and elevation of serum aminotransferases on POD 1 (r2=0.61, p<0.001). CONCLUSIONS: High levels of PCT after pLTx are an early indicator of poor postoperative outcome and may reflect ischemia induced liver cell injury within the context of an ischemia- reperfusion injury.

Growing experience with mTOR inhibitors in pediatric solid organ transplantation.

Controlled trials of mTOR inhibitors in children following solid organ transplantation are scarce, although evidence from prospective single-arm studies is growing. Everolimus with reduced CNI therapy has been shown to be efficacious and safe in de novo pediatric kidney transplant patients in prospective trials. Prospective and retrospective data in children converted from CNI therapy to mTOR inhibition following kidney, liver, or heart transplantation suggest preservation of immunosuppressive efficacy. Good renal function has been maintained when mTOR inhibitors are used de novo in children following kidney transplantation or after conversion to mTOR inhibition with CNI minimization. mTOR inhibition with reduced CNI exposure is associated with a low risk for developing infection in children. Growth and development do not appear to be impaired during low-dose mTOR inhibition, but more studies are required. No firm conclusions can be drawn as to whether mTOR inhibitors should be discontinued in children requiring surgical intervention or whether mTOR inhibition delays progression of hepatic fibrosis after pediatric liver transplantation. In conclusion, current evidence suggests that use of mTOR inhibitors in children undergoing solid organ transplantation is efficacious and safe, but a number of issues remain unresolved and further studies are required.

[Scrotal ultrasound in children and adolecents with duplex Doppler analysis of intratesticular arteries]. / Hodensonografie bei Kindern und Jugendlichen mit Bestimmung Doppler-sonografischer Referenzwerte der intratestikulären Arterien.

PURPOSE: Scrotal ultrasound, color Doppler and spectral Doppler analysis of intratesticular arteries are the most common and important examinations in boys with scrotal pain. In the existing literature information concerning feasibility and reference values of color Doppler and spectral Doppler in small testes is inconsistent. MATERIALS AND METHODS: In the present study 102 boys from 2 days to 16 years old without present or anamnestic scrotal disease were examined in a standardized manner. Using linear scanners (9 - 14 mHz), testicular volumetry and spectral Doppler analysis of typical intratesticular arteries were performed and the paratesticular structures were examined. For analysis we grouped the testes by volume and compared the measured values V. max syst., V. max enddiast., and RI. RESULTS: In all test subjects a complete examination with spectral Doppler analysis of intratesticular arteries could be performed. With increasing testicular volume, there is a linear increase in blood flow velocities V. max syst. and V. enddiast. Irrespective of age and testicular volume, the RI of the intratesticular arteries is 0.54 ± 0.08. CONCLUSION: In contrast to published data, this study shows that color Doppler and spectral Doppler of testicular arteries can be regularly performed even in small testes of less than 1 ml. Reference values for blood flow velocities and RI were found and should improve the diagnostic value of testicular ultrasound examinations in children.

Super selective percutaneous transhepatic coil embolization of intrahepatic pseudoaneurysm after pediatric liver transplantation: a case report.

BACKGROUND: Intrahepatic arterial pseudoaneurysms are a rare, life-threatening complication after pediatric liver transplantation. Treatment of choice represents interventional radiological management with endovascular embolization of the segmental artery proximal and distal to the aneurysm. However, this technique results in loss of arterial perfusion distal to the aneurysm with subsegment arterial ischemia. CASE PRESENTATION: We report a case of a 1-year-old girl with a pseudoaneurysm in the split-liver graft. Direct percutaneous, transhepatic access to the pseudoaneurysm was performed followed by super selective coil application into the aneurysm. CONCLUSION: Super selective percutaneous, transhepatic coil application is feasible even in pediatric patients after liver transplantation and results in preservation of the entire course of the liver artery.

[Chronically ill children become grown-up. What does the internist learn from the pediatrician?]. / Chronisch kranke Kinder werden erwachsen. Was lernt der Internist vom Pädiater?

Transition from the protective, child and family centered pediatric care to the adult health care system with the expectation of patient self care and self management, is challenging the adolescent as well as his adult specialist. The young patients often show a delayed somatic and psychosocial development and oppose not only against their parents but also against their medical team. Adult specialists feel not well trained and experienced in dealing with adolescents. They are worried about the difficulties in the guidance of the patients and the non adherence to therapeutic recommendations. Due to medical progress, many children with severe or/and fatal chronic disorders are now surviving into adulthood. Profound knowledge of diseases that were known until now almost exclusively in the pediatric population as well as an awareness of normal physical, mental and psychosocial development of childhood and adolescence is not training content of German internists. The intention of this article is to discuss some of the experiences of pediatricians that might be helpful to internists to take better care for these special young patients.

European biliary atresia registries: summary of a symposium.

Biliary atresia (BA) is a rare but potentially devastating disease. The European Biliary Atresia Registry (EBAR) was set up to improve data collection and to develop a pan-national and interdisciplinary strategy to improve clinical outcomes. From 2001 to 2005, 100 centers from 22 countries registered with EBAR via its website (www.biliary-atresia.com). In June 2006, the first meeting was held to evaluate results and launch further initiatives. During a 5-year period, 60 centers from 19 European countries and Israel sent completed registration forms for a total of 514 BA patients. Assuming the estimated incidence of BA in Europe is 1:18,000 live births, 35% of the expected 1488 patients from all EBAR participating countries were captured, suggesting that reporting arrangements need improvement. At the meeting, the cumulative evaluation of 928 BA patients including patients from other registries with variable follow-up revealed an overall survival of 78% (range from 41% to 92%), of whom 342 patients (37%) have had liver transplants. Survival with native liver ranged from 14% to 75%. There was a marked variance in reported management and outcome by country (e.g., referral patterns, timing of surgery, centralization of surgery). In conclusion, EBAR represents the first attempt at an overall evaluation of the outcome of BA from a pan-European perspective. The natural history and outcome of biliary atresia is of considerable relevance to a European population. It is essential that there is further support for a pan-European registry with coordination of clinical standards, further participation of parent support groups, and implementation of online data entry and multidisciplinary clinical and basic research projects.

Tacrolimus Aggravated Tube Feeding Syndrome with Acute Renal Failure in a Pediatric Liver Transplant Recipient.

Acute renal failure can be caused by calcineurin inhibitors (CNIs), due to arteriolopathy and altered tubular function. Within this context, we present the case of a 14-month-old liver transplant recipient who suffered an acute polyuric renal failure during a short episode of hypercaloric feeding. In our case, CNI-induced distal RTA led to nephrocalcinosis and therefore to secondary nephrogenic diabetes insipidus. The diet with high renal solute load consequently resulted in an acute polyuric renal failure with severe hypernatremic dehydration. In conclusion, a hypercaloric diet in children with potentially impaired renal function due to therapy with CNIs requires precise calculation of the potential renal solute load and the associated fluid requirements.

Glucose Metabolism and Associated Outcome After Pediatric Liver Transplantation.

BACKGROUND: Despite hypoglycemia and hyperglycemia being frequently observed in the early postoperative phase, information on glucose metabolism after pediatric liver transplantation (pLT) is scarce. METHODS: The goal of this retrospective single-center study, which included 46 patients who consecutively underwent 55 liver transplantations, was to gather data on glucose uptake, the prognostic relevance of hyperglycemia, and the safety of insulin administration in patients after pLT. RESULTS: In this study population, glucose intake to keep blood sugar levels (BSLs) within the targeted range of 120 to 200 mg/dL (6.7-11.1 mmol/L) increased rapidly over the first few postoperative days and was significantly correlated with graft function. There was no association between a postoperative daily mean BSL >200 mg/dL and specific posttransplant complications (acute rejection, infection, need for retransplantation, and/or death). High postoperative mean 7-day BSLs were associated with poor glucose metabolism and an increase in morbidity and 6-month posttransplant mortality. Hypoglycemia was not observed under insulin administration. CONCLUSIONS: With high BSLs being associated with poor glucose metabolism, it is likely that the critical illness itself, in addition to poor graft function, causes the increase in morbidity and mortality, with hyperglycemia serving as a marker.

Expression of the chemokine receptor CXCR3 and its ligand IP-10 during human cardiac allograft rejection.

BACKGROUND: Chemokines play an essential role in regulating the infiltration of leukocytes into allografts in experimental models. Little is known of their expression or function after human cardiac transplantation. METHODS AND RESULTS: We analyzed 169 sequential human endomyocardial biopsies by immunocytochemistry for infiltration by CD3(+) T cells and the expression of the chemokine receptors CCR1, CCR3, CCR5, and CXCR3. In both cross-sectional and longitudinal analyses, the expression of each of the chemokine receptors correlated with the degree of CD3(+) T-cell infiltration. In particular, the expression of CXCR3 was temporally and spatially associated with CD3(+) T-cell infiltrates and correlated with the histopathological diagnosis of acute rejection (OR, 11.73 and 4.05, respectively; P<0.001). Of 7 patients followed up longitudinally for 1 year, 4 with consecutive biopsies developed intimal thickening by intravascular ultrasound. In these patients, there was a trend for persistent expression of CD3- and CXCR3-expressing infiltrates in the later part of the first posttransplant year. The chemokines eotaxin, IP-10, lymphotactin, MCP-1, Mig, RANTES, and SDF-1 were examined in an additional 35 biopsies by RT-PCR. Eotaxin, lymphotactin, MCP-1, Mig, and SDF-1 were present in both normal and rejecting biopsies. However, the CXCR3 ligand IP-10, which was rarely expressed in normal biopsies, was markedly induced in acute rejection (OR, 19.43; P=0.01). CONCLUSIONS: The presence of CXCR3(+) T cells and the CXCR3 ligand IP-10 within endomyocardial biopsies is strongly associated with acute rejection. The CXCR3-IP-10 interaction warrants consideration as a therapeutic target in the management of cardiac allograft recipients.

Laparoscopic partial external biliary diversion procedure in progressive familial intrahepatic cholestasis: a new approach.

BACKGROUND: Progressive familial intrahepatic cholestasis results in fibrosis, cirrhosis, and liver insufficiency if untreated. Medical therapy often fails and partial external biliary diversion has been recommended to prevent early liver transplantation. We present a new technique of performing a laparoscopic partial external biliary diversion and report our experience in a first series of infants. METHODS: From October to November 2004, four consecutive patients with progressive familial intrahepatic cholestasis underwent the laparoscopic partial biliary diversion procedure. A three-trocar technique was used. A proximal jejunal conduit was constructed after exteriorization of the small bowel via the infraumbilical trocar incision. After repositioning of the bowel, an isoperistaltic cholecystojejunostomy was carried out laparoscopically. The distal jejunal conduit was placed as a stoma at the right abdominal trocar site. RESULTS: There were no intraoperative events. The mean duration of the operation was 156.5 min. The postoperative course was uneventful in all patients with full enteral feedings on day 2. The laboratory and clinical signs of cholestasis were reduced up to a mean follow-up of 2 months (range, 1.5-2.5). CONCLUSION: The laparoscopic partial biliary diversion procedure is feasible with all the benefits of minimally invasive surgery. Long-term results remain to be evaluated.

Evaluation of the diagnostic accuracy of CEUS in children with benign and malignant liver lesions and portal vein anomalies.

OBJECTIVE: Comparison of the diagnostic findings of MRI, CT and CEUS in children with benign and malignant and portal venous anomalies of the liver. MATERIALS/METHODS: Retrospective analysis of the diagnostic findings of CEUS, MRI and CT scans in 56 children (age 0-17 years) with a total of 60 benign and malignant liver lesions and anomalies of the portal vein/perfusion. All patients underwent CEUS using sulphur hexafluoride microbubbles and a multi-frequency probe (1-5 MHz, 6-9 MHz). Cine-loops were stored up to 3 minutes. MRI was performed in 38 lesions. CT was performed in 8 lesions. RESULTS: Out of the 56 patients 49 liver lesions (48 benign, 1 malignant), 9 anomalies of the portal vein/perfusion and 2 of the biliary system were detected. 16/49 lesions were analyzed histopathologically. Using CEUS, the characterization of the lesions was possible in 45 out of 49 cases. In 32 cases, CEUS provided the exact diagnosis. Only two benign lesions were falsely categorized as malignant.Findings of MRI and CEUS were concordant in 84% of cases (n = 32/38). CEUS considered 1 benign lesion to be malignant. 2 lesions were not detectable and in 3 lesions no definite diagnosis was established using MRI.Findings of CT and CEUS were concordant in 5 of 8 cases. In 21 lesions CEUS as the only imaging modality was found to be sufficient for diagnostics. CONCLUSION: Despite the restricted indications for using CEUS in children, it offers a high diagnostic detection rate (93%) for characterization of liver lesions and portal vein anomalies.

Liver transplantation in children with chronic end stage liver disease: factors influencing survival after transplantation.

To identify pretransplant factors that are influencing survival after orthotopic liver transplantation a Cox proportional hazards regression model was applied to 118 children with chronic terminal liver failure transplanted at Medical School Hannover during the period of 1978 to 1994. The response variable was survival, as covariates a total of 19 pretransplant variables were entered--i.e. age, diagnosis (biliary cirrhosis, metabolic cirrhosis, postnecrotic cirrhosis, cryptogenetic cirrhosis) sex, laparotomy prior to OLT, height, weight, standard deviation scores for height and weight, date of first OLT, serum alanine aminotransferase, asparagine aminotransferase, albumin, total bilirubin, cholinesterase activity, glomerular filtration rate, and prothrombin time. Significant independent predictors of survival after OLT were bilirubin (P=0.0024), SDS for weight (P=0.034), and albumin (P=0.039). In a subsequent discriminant analysis cut off points for these variables could be identified--i.e., bilirubin >340 micromol/L, SDS for weight <-2.2 and albumin < 33 g/L. Patients with one or more of these risk factors were grouped as urgent indication group (n=76) and those with no risk factor as elective indication group (n=42). Comparing the posttransplantation survival in these groups there is a statistically significant difference at 1 year (57% vs. 90.5%) and 4 years (49% vs. 90.5%) after OLT (P=0.0001, log rank test). It is concluded that the risk of OLT is much higher if liver function is very poor. Optimal nutritional support prior to transplantation is mandatory to optimise the clinical status of the children and to improve the results of OLT.

Challenges after pediatric transplantation.

In this review we address the current challenges facing the pediatric transplant caregiver. We focus most of our discussion on recent developments that have resulted in improved graft survival in renal allograft recipients. We discuss the issue of growth failure posttransplant and the realization that it is time to reassess strategies that optimize the immunosuppression and growth after pediatric transplantation. Lastly, we discuss some recent findings suggesting that these issues are also of critical importance for success after pediatric liver transplantation.

Treatment of copper associated liver disease in childhood.

BACKGROUND/AIMS: Copper associated liver disease is accompanied with high liver copper concentrations and progressive liver disease in infancy or childhood. The disease is thought to be due to excessive dietary copper overload (copper-enriched water supply) and in addition to be based on a genetic predisposition. Treatment with penicillamine in Indian childhood disease, which probable has the same etiology, is effective when it is started early enough as well as in Wilson's disease. We aimed to describe the clinical features of copper associated liver disease and report our experience with different treatment options in German children. METHODS/RESULTS: Two boys presented at the age of 6 and 10 months with abdominal distension due to hepatosplenomegaly. The diagnosis of copper associated liver disease was made based on feeding history, standard liver function parameters, liver biopsy and assessment of dry weight copper concentration and urinary excretion of copper. Both had micronodular cirrhosis, ballooning of hepatocytes and Mallory bodies. In child A improvement of liver function was observed after introduction of penicillamine therapy and copper-reduced diet. The treatment was stopped after 18 months, when normalisation of copper concentration in the liver had occured. In child B acute liver failure developed despite initiation of treatment. The boy was transplanted successfully. Both children are presently healthy 10 years after transplantation and 4 years after begin of chelating therapy, respectively. CONCLUSIONS: We conclude, that early chelating therapy with penicillamine can be successful in children with copper associated liver disease. In case of delayed diagnosis and acute liver failure liver transplantation is necessary. Our case reports highlight the urgent need of rapid diagnosis of copper associated liver disease in order to initiate early chelating therapy. Copper associated liver disease should obviously be considered in liver disease of unknown origin. Possible causes of excessive dietary copper intake should be ascertained.

Kinetics of interleukin-6, procalcitonin, and C-reactive protein after pediatric liver transplantation.

In the early phase after pediatric liver transplantation (pLT) several concomitant factors may reduce the performance of established sepsis markers. To date, their clinical interpretation is hindered by a lack of information on their postoperative kinetics. To gather more information on the postoperative course and their changes in bacterial sepsis, we prospectively studied C-reactive protein (CRP), interleukin-6 (IL-6), and procalcitonin (PCT) on 9 perioperative days in 25 consecutive pLTs. After an initial postoperative peak, IL-6 and CRP levels significantly re-increased in patients with bacterial sepsis (P < .001). In contrast, PCT had very high postoperative levels; therefore severe infection was a comparatively inferior trigger for PCT elevation compared with the initial operation. The area under the receiver operating characteristic curve to diagnose postoperative sepsis for PCT was only 0.52, compared with 0.95 for IL-6 and 0.89 for CRP. None of the studied biomarkers were depressed by poor graft function. In conclusion, PCT performs poorly as a biomarker for sepsis in the early phase after pLT. With a rapid decline of initially elevated levels, IL-6 provides the best kinetics for detection of postoperative bacterial sepsis.