Utilization of Segmental Grafts Is Associated With Higher Transplant Rates in Pediatric Patients

INTRODUCTION

In July 2017, a policy to increase the use of segmental grafts (SGs) was implemented at our institution. The aim was to compare changes in waitlist activity after implementation of this policy.

METHODS

A single-center, retrospective study. Pediatric patients on the liver waiting list between January 2015 and December 2019 were screened. Patients were classified as receiving a liver transplant (LT) before (Period 1) or after (Period 2) policy changes. Primary end points were transplant rates and time to transplant.

RESULTS

Sixty five first LT performed on 65 patients were included. Twenty nine LT were performed during Period 1 and 36 during Period 2. More than half (55%) of LT in Period 2 were SG, compared to 10.3% in Period 1 (P < 0.001). Forty nine and 56 pediatric candidates on the waiting list accounted for 38.78 and 24.48 person-years during Period 1 and Period 2, respectively. Transplant rates per 100 person-years on the waiting list increased from 85.09 during Period 1 to 187.87 in Period 2 (Rate ratio: 2.20; P < 0.001). Median time to receive a LT decreased from 229 d in Period 1 to 75 d during Period 2 (P = 0.013). One-year patient survival rates were 96.6% in Period 1 and 95.7% in Period 2. One-year graft survival rates were 89.7% and 88% in Period 1 and Period 2, respectively.

CONCLUSIONS

A policy to increase the use of SG was associated with significantly higher transplant rates and lower waiting times. Implementation of this policy can be done successfully with no observed negative impact on patient and graft survival.

Serum biomarkers correlated with liver stiffness assessed in a multicenter study of pediatric cholestatic liver disease

BACKGROUND AND AIMS

Detailed investigation of the biological pathways leading to hepatic fibrosis and identification of liver fibrosis biomarkers may facilitate early interventions for pediatric cholestasis.

APPROACH AND RESULTS

A targeted enzyme-linked immunosorbent assay-based panel of nine biomarkers (lysyl oxidase, tissue inhibitor matrix metalloproteinase (MMP) 1, connective tissue growth factor [CTGF], IL-8, endoglin, periostin, Mac-2-binding protein, MMP-3, and MMP-7) was examined in children with biliary atresia (BA; n = 187), alpha-1 antitrypsin deficiency (A1AT; n = 78), and Alagille syndrome (ALGS; n = 65) and correlated with liver stiffness (LSM) and biochemical measures of liver disease. Median age and LSM were 9 years and 9.5 kPa. After adjusting for covariates, there were positive correlations among LSM and endoglin ( p = 0.04) and IL-8 ( p < 0.001) and MMP-7 ( p < 0.001) in participants with BA. The best prediction model for LSM in BA using clinical and lab measurements had an R2 = 0.437; adding IL-8 and MMP-7 improved R2 to 0.523 and 0.526 (both p < 0.0001). In participants with A1AT, CTGF and LSM were negatively correlated ( p = 0.004); adding CTGF to an LSM prediction model improved R2 from 0.524 to 0.577 ( p = 0.0033). Biomarkers did not correlate with LSM in ALGS. A significant number of biomarker/lab correlations were found in participants with BA but not those with A1AT or ALGS.

CONCLUSIONS

Endoglin, IL-8, and MMP-7 significantly correlate with increased LSM in children with BA, whereas CTGF inversely correlates with LSM in participants with A1AT; these biomarkers appear to enhance prediction of LSM beyond clinical tests. Future disease-specific investigations of change in these biomarkers over time and as predictors of clinical outcomes will be important.

Risk of variceal hemorrhage and pretransplant mortality in children with biliary atresia

BACKGROUND AND AIMS

The natural history of gastroesophageal variceal hemorrhage (VH) in biliary atresia (BA) is not well characterized. We analyzed risk factors, incidence, and outcomes of VH in a longitudinal multicenter study.

APPROACH AND RESULTS

Participants enrolled in either an incident (Prospective Database of Infants with Cholestasis [PROBE]) or prevalent (Biliary Atresia Study of Infants and Children [BASIC]) cohort of BA were included. Variceal hemorrhage (VH) was defined based on gastrointestinal bleeding in the presence of varices accompanied by endoscopic or nontransplant surgical intervention. Cumulative incidence of VH and transplant-free survival was compared based on features of portal hypertension (e.g., splenomegaly, thrombocytopenia) and clinical parameters at baseline in each cohort (PROBE: 1.5 to 4.5 months after hepatoportoenterostomy [HPE]; BASIC: at enrollment > 3 years of age). Analyses were conducted on 869 children with BA enrolled between June 2004 and December 2020 (521 in PROBE [262 (51%) with a functioning HPE] and 348 in BASIC). The overall incidence of first observed VH at 5 years was 9.4% (95% CI: 7.0-12.4) in PROBE and 8.0% (5.2-11.5) in BASIC. Features of portal hypertension, platelet count, total bilirubin, aspartate aminotransferase (AST), albumin, and AST-to-platelet ratio index at baseline were associated with an increased risk of subsequent VH in both cohorts. Transplant-free survival at 5 years was 45.1% (40.5-49.6) in PROBE and 79.2% (74.1-83.4) in BASIC. Two (2.5%) of 80 participants who had VH died, whereas 10 (12.5%) underwent transplant within 6 weeks of VH.

CONCLUSIONS

The low risk of VH and associated mortality in children with BA needs to be considered in decisions related to screening for varices and primary prophylaxis of VH.

Severe Acute Respiratory Syndrome Coronavirus-2 Infection in Children With Liver Transplant and Native Liver Disease: An International Observational Registry Study

OBJECTIVE

Increased mortality risk because of severe acute respiratory syndrome coronavirus-2 (SARS-CoV2) infection in adults with native liver disease (LD) and liver transplant (LT) is associated with advanced age and comorbid conditions. We aim to report outcomes for children with LD and LT enrolled in the NASPGHAN/SPLIT SARS-CoV2 registry.

METHODS

In this multicenter observational cohort study, we collected data from 91 patients <21 years (LD 44, LT 47) with laboratory-confirmed SARS-CoV2 infection between April 21 and September 17, 2020.

RESULTS

Patients with LD were more likely to require admission (70% vs 43% LT, P = 0.007) and pediatric intensive care unit (PICU) management (32% vs 4% LT, P = 0.001). Seven LD patients required mechanical ventilation (MV) and 2 patients died; no patients in the LT cohort died or required MV. Four LD patients presented in pediatric acute liver failure (PALF), 2 with concurrent multisystem inflammatory syndrome in children (MIS-C); all recovered without LT. Two LD patients had MIS-C alone and 1 patient died. Bivariable logistic-regression analysis found that patients with nonalcoholic fatty LD (NAFLD) (odds ratio [OR] 5.6, P = 0.02) and LD (OR 6.1, P = 0.01, vs LT) had higher odds of severe disease (PICU, vasopressor support, MV, renal replacement therapy or death).

CONCLUSIONS

Although not directly comparable, LT recipients had lower odds of severe SARS-CoV2 infection (vs LD), despite immunosuppression burden. NAFLD patients reported to the registry had higher odds of severe SARS-CoV2 disease. Future controlled studies are needed to evaluate effective treatments and further stratify LD and LT patients with SARS-CoV2 infection.

Society of pediatric liver transplantation: Current registry status 2011-2018

BACKGROUND

SPLIT was founded in 1995 in order to collect comprehensive prospective data on pediatric liver transplantation, including waiting list data, transplant, and early and late outcomes. Since 2011, data collection of the current registry has been refined to focus on prospective data and outcomes only after transplant to serve as a foundation for the future development of targeted clinical studies.

OBJECTIVE

To report the outcomes of the SPLIT registry from 2011 to 2018.

METHODS

This is a multicenter, cross-sectional analysis characterizing patients transplanted and enrolled in the SPLIT registry between 2011 and 2018. All patients, <18 years of age, received a first liver-only, a combined liver-kidney, or a combined liver-pancreas transplant during this study period.

RESULTS

A total of 1911 recipients from 39 participating centers in North America were registered. Indications included biliary atresia (38.5%), metabolic disease (19.1%), tumors (11.7%), and fulminant liver failure (11.5%). Greater than 50% of recipients were transplanted as either Status 1A/1B or with a MELD/PELD exception score. Incompatible transplants were performed in 4.1%. Kaplan-Meier estimates of 1-year patient and graft survival were 97.3% and 96.6%. First 30 days of surgical complications included reoperation (31.7%), hepatic artery thrombosis (6.3%), and portal vein thrombosis (3.2%). In the first 90 days, biliary tract complications were reported in 13.6%. Acute cellular rejection during first year was 34.7%. At 1 and 2 years of follow-up, 39.2% and 50.6% had normal liver tests on monotherapy (tacrolimus or sirolimus). Further surgical, survival, allograft function, and complications are detailed.

Revision of meso-Rex bypass utilizing a collateral vein in a patient with portal steal phenomenon after liver transplant: A case report

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Re-do of a meso-Rex Bypass is a feasible option with good outcomes.

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A large collateral vein is an alternative for an autologous venous conduit in a MRB.

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Large collaterals ligation during MRB should be performed to avoid portal steal.

Introduction

In children with extrahepatic portal vein obstruction or those who develop portal vein thrombosis after liver transplant, the use of Meso-Rex Bypass (MRB) creates a more physiological state by redirecting mesenteric blood flow back into the intrahepatic portal system via a venous conduit.

Presentation of case

A 3-year-old female with biliary atresia associated with polysplenia syndrome and a surgical history of Kasai portoenterostomy procedure, and an ABO incompatible whole liver transplant. Within a year after transplant she presented with prehepatic portal hypertension, that was treated with MRB using a deceased donor ABO compatible iliac vein as conduit. Six months later, she was taken to the operating room for bypass revision, during the procedure the MRB showed no flow and no thrombus, and a large splenorenal collateral vein that was causing a portal perfusion steal phenomenon was observed. After dissecting the collateral vein, an 8 cm x8 mm segment of this vessel was used as an autologous conduit to re-do the Rex.

Discussion

Failed of MRB can be attributed to portal steal phenomenon, hypercoagulable disorders, bypass contraction or kinking. In this case we believe the culprit to be the former. When there is a history of longstanding portal hypertension, large collaterals develop; thus, intraoperative portal vein flow measurement is critical and ligation of large collaterals during liver transplantation and MRB should be performed to avoid portal steal phenomenon postprocedure.

Conclusion

Using a collateral vein as an alternative autologous venous conduit is a feasible option that can have durable success.

The Impact of Increased Allocation Priority for Children Awaiting Liver Transplant: A Liver Simulated Allocation Model (LSAM) Analysis

OBJECTIVE

The aim of the study was to investigate the impact of prioritizing infants, children, adolescents, and the sickest adults (Status 1) for deceased donor livers. We compared outcomes under two "SharePeds" allocation schema, which prioritize children and Status 1 adults for national sharing and enhanced access to pediatric donors or all donors younger than 35 years, to outcomes under the allocation plan approved by the Organ Procurement and Transplant Network in December 2017 (Organ Procurement and Transplantation Network [OPTN] 12-2017).

METHODS

The 2017 Liver Simulated Allocation Model and Scientific Registry of Transplant Recipients data on all US liver transplant candidates and liver offers 7/2013 to 6/2016 were used to predict waitlist deaths, transplants, and post-transplant deaths under the OPTN 12-2017 and SharePeds schema.

RESULTS

Prioritizing national sharing of pediatric donor livers with children (SharePeds 1) would decrease waitlist deaths for infants (<2 years, P = 0.0003) and children (2-11 years, P = 0.001), with no significant change for adults (P = 0.13). Prioritizing national sharing of all younger than 35-year-old deceased donor livers with children and Status 1A adults (SharePeds 2) would decrease waitlist deaths for infants, children, and all Status 1A/B patients (P < 0.0001 for each). SharePeds 1 and 2 would increase the number of liver transplants done in infants, children, and adolescents compared to the OPTN-2017 schema (P < 0.00005 for all age groups). Both SharePeds schema would increase the percentage of pediatric livers transplanted into pediatric recipients.

CONCLUSIONS

Waitlist deaths could be significantly decreased, and liver transplants increased, for children and the sickest adults, by prioritizing children for pediatric livers and with broader national sharing of deceased donor livers.

Liver transplant for metastatic pancreatoblastoma: 7-year event-free survival after chemotherapy, pancreatectomy, complete hepatectomy, and liver transplant

Pancreatoblastoma is a rare malignant tumor in children. Surgical resection of the tumor is necessary for cure; however, due to its aggressive nature, it is often unresectable at presentation due to tumor size, local invasion, and/or metastasis. Because it is a rare tumor, there is currently no standard treatment regimen. We report a case of a 4-year-old boy who presented with metastatic pancreatoblastoma with multiple large metastases involving all four sectors of the liver. We began treatment with chemotherapy (cisplatin, 5FU, vincristine, and doxorubicin), which significantly reduced the tumor burden in both the pancreas and liver. We then performed a staged subtotal pancreatectomy, complete hepatectomy, and living donor left lateral segment liver transplant. This was followed by postoperative adjuvant chemotherapy. Our patient is alive and healthy and has now been tumor-free for 7 years with no tumor relapse.

Identification of Pediatric Patients With Celiac Disease Based on Serology and a Classification and Regression Tree Analysis

BACKGROUND & AIMS

Celiac disease is detected using serology and endoscopy analyses. We used multiple statistical analyses of a geographically isolated population in the United States to determine whether a single serum screening can identify individuals with celiac disease.

METHODS

We performed a retrospective study of 3555 pediatric patients (18 years old or younger) in the intermountain West region of the United States from January 1, 2008, through September 30, 2013. All patients had undergone serologic analyses for celiac disease, including measurement of antibodies to tissue transglutaminase (TTG) and/or deamidated gliadin peptide (DGP), and had duodenal biopsies collected within the following year. Modified Marsh criteria were used to identify patients with celiac disease. We developed models to identify patients with celiac disease using logistic regression and classification and regression tree (CART) analysis.

RESULTS

Single use of a test for serum level of IgA against TTG identified patients with celiac disease with 90% sensitivity, 90% specificity, a 61% positive predictive value (PPV), a 90% negative predictive value, and an area under the receiver operating characteristic curve value of 0.91; these values were higher than those obtained from assays for IgA against DGP or IgG against TTG plus DGP. Not including the test for DGP antibody caused only 0.18% of celiac disease cases to be missed. Level of TTG IgA 7-fold the upper limit of normal (ULN) identified patients with celiac disease with a 96% PPV and 100% specificity. Using CART analysis, we found a level of TTG IgA 3.2-fold the ULN and higher to most accurately identify patients with celiac disease (PPV, 89%). Multivariable CART analysis showed that a level of TTG IgA 2.5-fold the ULN and higher was sufficient to identify celiac disease in patients with type 1 diabetes (PPV, 88%). Serum level of IgA against TTG in patients with versus those without trisomy 21 did not affect diagnosis predictability in CART analysis.

CONCLUSIONS

In a population-based study, we found that serum level of IgA against TTG can identify patients with celiac disease with PPVs of about 90%. Predictive values increase greatly when levels are markedly above the ULN or when the assay is used in combination with other variables. Measurement of IgG against TTG or DGP does not increase the accuracy of detection of celiac disease based against TTG IgA levels. There is a low risk of false-positive results from serologic analysis in patients with type I diabetes or persistent increases in antibody against TTG on repeat testing.

Cholangiocarcinoma and high-grade dysplasia in young patients with primary sclerosing cholangitis

INTRODUCTION

Cholangiocarcinoma (CCA) is very often an adulthood disease with primary sclerosing cholangitis (PSC) as one of the risk factors. It is rarely seen in the pediatric population, and when it is diagnosed before adulthood, it can be associated with PSC as well as HIV infection, biliary atresia, radiation therapy, and choledochal cyst. Although there have been some case reports of pediatric CCA, cases of childhood CCA associated with PSC are still relatively rare.

AIM

To describe the clinical and pathologic features of CCA in pediatric patients with previously diagnosed PSC.

METHODS

Retrospective study

RESULTS

Four patients with PSC (age range 15-18, mean 17 years) were included in this study. All patients underwent ERCP for diagnosis. Tissue samples obtained included routine cytology and FISH. ERCP was used to target sites for tissue acquisition in all patients. 3/4 of patients have inflammatory bowel disease (two Crohn's disease and one ulcerative colitis). Alkaline phosphatase was elevated in 3/4 patients, aspartate aminotransferase/alanine aminotransferase were elevated in 2/4 patients, and total bilirubin/direct bilirubin were elevated in 2/4 patients. 4/4 patients had positive FISH studies, and 3/4 patients had brush cytology concerning for CCA. 2/4 patients received chemotherapy, one patient underwent orthotopic liver transplant, and one patient underwent Whipple procedure. Two patients died soon after being diagnosed.

CONCLUSIONS

Young patients with PSC can develop CCA. This finding has implications for both screening and surveillance for cancer in pediatric patients with PSC.

Liver transplantation in a 7-month-old girl with Caroli's disease

Caroli's disease (including Caroli's syndrome) is a rare autosomal recessive disorder of the liver characterized by diffuse cystic dilatation of the intrahepatic bile ducts. The disease may present at any age and is characterized by recurrent episodes of biliary obstruction, cholangitis, hepaticolithiasis, and liver abscesses. Caroli's syndrome is further associated with congenital hepatic fibrosis and portal hypertension. Patients with recurrent complications or cirrhosis may die because of recurrent infection, portal hypertension, liver failure, or cholangiocarcinoma. Liver transplantation is the treatment of choice for these complicated patients. Here we describe the youngest reported patient with Caroli's syndrome treated successfully using liver transplantation and review the recent literature.

Plasmapheresis treatment of antibody-mediated rejection in an A2 donor to O pediatric liver transplant recipient

It is safe to transplant kidneys from blood group A2 donors into O recipients if the latter have low titers of anti-A antibodies. However, in liver transplantation, O and B recipients of A2 donor livers are not routinely screened for anti-blood group antibodies because of the immuno-absorptive capacity of the liver and the low incidence of antibody-mediated rejection. Herein, we report a rare case of combined cell and antibody-mediated rejection in a pediatric blood group O recipient of an A2 donor liver, and rescue of the allograft using PP and IVIG.

Genome-wide linkage analysis of 160 North American families with celiac disease

Celiac disease (CD) is a common autoimmune disease caused by exposure to the protein gliadin in wheat, and related prolamins in barley and rye. The prevalence of the disease in the US is 1:133. The aim of this study was to identify non-human leukocyte antigen (HLA) loci that predispose to CD. A genome-wide search of 405 microsatellite markers was performed on DNA samples from 160 families with a minimum of two cases of CD. Multipoint, parametric and non-parametric linkage (NPL) analyses were performed. Locations on chromosomes 1q, 3q, 6p, 6q, 7q, 9q and 10q showed linkage statistics (NPL scores or heterogeneity logarithm of the odds (HLOD) scores) of approximately 2.0 or larger. The greatest evidence for linkage outside of chromosome 6 was on 7q and 9q. An NPL score of 2.60 occurred at position 151.0 on 7q and a HLOD score of 2.47 occurred at position 144.8 on 9q under a recessive model. As expected, there was highly significant linkage to the HLA region on 6p, with NPL and HLOD scores exceeding 5.50. In conclusion, this genome-wide linkage analysis represents one of the largest such studies of CD. The most promising region is a putative locus on 7q, a region reported independently in previous genome-wide searches.

Multicenter, randomized, double-blind study comparing 20 and 40 mg of pantoprazole for symptom relief in adolescents (12 to 16 years of age) with gastroesophageal reflux disease (GERD)

An age-appropriate questionnaire (GASP-Q) was used to assess the frequency and severity of the gastroesophageal reflux disease (GERD) symptoms: abdominal/belly pain, chest pain/heartburn, pain after eating, nausea, burping/belching, vomiting/regurgitation, choking when eating, and difficulty swallowing, in adolescents age 12 to 16 years. The primary objective was to compare the mean composite symptom score (CSS) at week 8 with baseline after treatment with 20 or 40 mg of pantoprazole. Statistically significant (p < 0.001) improvement in CSS occurred in both groups. Safety was comparable between the 2 groups. Pantoprazole was safe, well tolerated, and effective in reducing symptoms of GERD in adolescents.

Pediatric celiac disease: clinicopathologic and genetic aspects

Evaluation for celiac disease (CD), an autoimmune enteropathy triggered by grain proteins in wheat, barley, rye, and possibly oats, is a common indication for pediatric endoscopy and biopsy. Duodenal or jejunal biopsy remains key for the initial diagnosis of CD. Small intestinal pathology may be diffuse or focal in CD, and histologic findings are nonspecific and must be interpreted in conjunction with clinical and serologic findings. A standardized grading system for CD biopsies is recommended. This review article summarizes the epidemiology, clinical manifestations, genetics, pathogenesis, and serologic and histologic findings of CD. Clinical management of CD and general handling of small intestinal biopsies are also addressed.

Efficacy of lansoprazole in the treatment of gastroesophageal reflux disease in children

OBJECTIVES

To assess the efficacy of lansoprazole for the relief of symptoms due to gastroesophageal reflux disease (GERD) in children 1 to 11 years of age. In addition, the efficacy in healing of erosive esophagitis (EE) was determined in those children with EE who were enrolled in the study.

METHODS

In this phase I/II, open-label, multicenter (11 sites) U.S. study, children with symptomatic GERD, EE by endoscopy, and/or intraesophageal pH < 4 for greater than 4.2% of the time based on 24-hour pH testing were assigned, on the basis of body weight, to lansoprazole 15 mg (< or = 30 kg) or 30 mg (> 30 kg) once daily for 8 to 12 weeks. At the discretion of the investigator, the dosage of lansoprazole was increased up to 60 mg daily in children who continued to be symptomatic after 2 weeks of treatment. Symptom response was assessed by investigator interview and daily diary. Esophagitis healing was evaluated by repeat endoscopy after 8 and, if applicable, 12 weeks of treatment.

RESULTS

Sixty-six children were enrolled. At week 8, 78% (21/27) of the children with EE at baseline had healed; the remaining six children were healed by week 12 (100%, 6/6). By investigator interview, 70% of children experienced resolution or improvement in their overall symptoms of GERD by their final visit. Statistically significant reductions from baseline in the severity of each symptom were reported with the exceptions of wheezing, hematemesis, and melena. Based on daily diary data, improvement in overall GERD symptoms was reported in 76% (47/62) of all children. With few exceptions, significant (P < 0.05) reductions from baseline occurred during each of the 2-week treatment intervals of the study period in the percentage of days and the average daily severity of GERD symptoms, the percentage of days antacid was used, and the average number of antacid tablets used per day.

CONCLUSION

In children 1 to 11 years of age, lansoprazole is efficacious in healing EE and in relieving GERD-related symptoms.

Pharmacokinetics and pharmacodynamics of lansoprazole in children with gastroesophageal reflux disease

OBJECTIVES

To evaluate the pharmacokinetics and pharmacodynamics of lansoprazole in children between 1 and 11 years of age with gastroesophageal reflux disease (GERD).

METHODS

In a multicenter, open-label trial of pediatric patients with symptomatic GERD, children were assigned, based on their weight, to receive lansoprazole 15 mg (patients weighing < or = 30 kg) or lansoprazole 30 mg (patients weighing > 30 kg) once daily. The effects of lansoprazole on 24-hour median intragastric pH, the percentages of time intragastric pH was above 3 and 4, and pharmacokinetic parameters were assessed at the day-5 visit and compared to baseline.

RESULTS

Sixty-six children were enrolled in the study. Mean lansoprazole C(max) values of 790.9 ng/mL and 898.5 ng/mL and T(max) values of 1.5 hours and 1.7 hours were observed in the < or = 30 kg and the > 30 kg body weight treatment groups, respectively. AUC0-24 values of 1707 ng x h/mL and 1883 ng x h/mL and T1/2 values of 0.68 hours and 0.71 hours were observed in the < or = 30 kg and > 30 kg lansoprazole body weight treatment groups, respectively. There was no statistical significant difference in AUC0-24 between the two groups (P = 0.2571). After 5 days of treatment lansoprazole produced significant increases in patients' 24-hour mean intragastric pH and the percentages of time intragastric pH was above 3 and 4 compared to baseline.

CONCLUSION

The observed pharmacokinetic properties of lansoprazole in children between 1 and 11 years of age with GERD were similar to those previously observed in healthy adult subjects. Lansoprazole significantly increased the mean 24-hour intragastric pH and the percentages of time intragastric pH was above 3 and 4 when children were dosed with either 15 or 30 mg according to body weight.

Prevalence of celiac disease among relatives of sib pairs with celiac disease in U.S. families

OBJECTIVE

Celiac disease is a familial malabsorptive disorder with an estimated prevalence in first-degree relatives of 10-12%. The prevalence for first-degree and more distant relatives has not been determined in families where there are two affected first-degree relatives. The aim of our investigation was to estimate the prevalence and relative risk for celiac disease in relatives of two siblings diagnosed with celiac disease.

METHODS

We ascertained sib pairs with celiac disease, and then identified all living first-degree relatives and available second-degree relatives to minimize ascertainment bias. We measured IgA endomysial antibodies, a highly specific and sensitive assay for celiac disease, in all subjects without a confirmed biopsy diagnosis. For those individuals with positive serologic tests, IgA tissue transglutaminase antibody tests and human leukocyte antigen DQA1 and DQB1 genotyping were performed for additional confirmation. Individuals with positive biopsy and/or serology were considered affected. We calculated the relative risk of being affected with celiac disease using the lambda(R) statistic.

RESULTS

The prevalence of celiac disease in relatives of affected sib pairs was as follows: 21.3% (13/61) of siblings (lambda(S) = 53); 14.7% (10/68) of offspring (lambda(O) = 37); 17.2% (28/163) of first-degree relatives; 19.5% (16/82) of second-degree relatives; and 17.8% (52/292) of all relatives (lambda(R) = 44.5).

CONCLUSIONS

In these families, we identified a sibling risk approximately double that found in previous reports, as well as significant risk for more distant relatives, probably because of sharing of a common gene. In families where at least two siblings have been diagnosed with celiac disease, relatives are at high risk for celiac disease. Screening should be considered for all family members.

Prevalence of celiac disease among relatives of sib pairs with celiac disease in U.S. families

OBJECTIVE

Celiac disease is a familial malabsorptive disorder with an estimated prevalence in first-degree relatives of 10-12%. The prevalence for first-degree and more distant relatives has not been determined in families where there are two affected first-degree relatives. The aim of our investigation was to estimate the prevalence and relative risk for celiac disease in relatives of two siblings diagnosed with celiac disease.

METHODS

We ascertained sib pairs with celiac disease, and then identified all living first-degree relatives and available second-degree relatives to minimize ascertainment bias. We measured IgA endomysial antibodies, a highly specific and sensitive assay for celiac disease, in all subjects without a confirmed biopsy diagnosis. For those individuals with positive serologic tests, IgA tissue transglutaminase antibody tests and human leukocyte antigen DQA1 and DQB1 genotyping were performed for additional confirmation. Individuals with positive biopsy and/or serology were considered affected. We calculated the relative risk of being affected with celiac disease using the lambda(R) statistic.

RESULTS

The prevalence of celiac disease in relatives of affected sib pairs was as follows: 21.3% (13/61) of siblings (lambda(S) = 53); 14.7% (10/68) of offspring (lambda(O) = 37); 17.2% (28/163) of first-degree relatives; 19.5% (16/82) of second-degree relatives; and 17.8% (52/292) of all relatives (lambda(R) = 44.5).

CONCLUSIONS

In these families, we identified a sibling risk approximately double that found in previous reports, as well as significant risk for more distant relatives, probably because of sharing of a common gene. In families where at least two siblings have been diagnosed with celiac disease, relatives are at high risk for celiac disease. Screening should be considered for all family members.

Genome-wide linkage analysis for celiac disease in North American families

Celiac disease (CD) is an autoimmune disease caused by sensitivity to the dietary protein gluten. It has a prevalence of 1 in 250 in the United States. Multiple-case families are common with a risk to siblings from 10-12%. Previous linkage studies have found no significant evidence for linkage other than to HLA. In this study, we performed a genome-wide search on 62 families with at least two cases of CD to identify non-HLA loci for CD. Two-point and multipoint parametric and nonparametric analyses were performed on the entire set of families and on sets stratified by the HLA genotype. Accounting for multiple testing, we found genome-wide intermediate linkage evidence at 18q (heterogeneity LOD (HLOD) = 3.6) and at 3p (HLOD = 3.2) and suggestive evidence at 5p (HLOD = 2.7). Good consensus between two-point and multipoint evidence was not found, and after genotyping with new markers in these regions, our results were inconclusive. The 18q region had intermediate two-point evidence, but weak multipoint evidence. At 3p and 5p, the addition of follow-up markers added flanking support, yet multipoint evidence was still lacking. Our results indicate that multipoint analyses may be hindered by the complexity of CD. Multipoint analyses are not robust to model misspecification, and further development of models is needed. Additional study of these and other families is necessary to validate or rule out the regions implicated in this study.

Linkage analysis of HLA and candidate genes for celiac disease in a North American family-based study

BACKGROUND

Celiac disease has a strong genetic association with HLA. However, this association only explains approximately half of the sibling risk for celiac disease. Therefore, other genes must be involved in susceptibility to celiac disease. We tested for linkage to genes or loci that could play a role in pathogenesis of celiac disease.

METHODS

DNA samples, from members of 62 families with a minimum of two cases of celiac disease, were genotyped at HLA and at 13 candidate gene regions, including CD4, CTLA4, four T-cell receptor regions, and 7 insulin-dependent diabetes regions. Two-point and multipoint heterogeneity LOD (HLOD) scores were examined.

RESULTS

The highest two-point and multipoint HLOD scores were obtained in the HLA region, with a two-point HLOD of 3.1 and a multipoint HLOD of 5.0. For the candidate genes, we found no evidence for linkage.

CONCLUSIONS

Our significant evidence of linkage to HLA replicates the known linkage and association of HLA with CD. In our families, likely candidate genes did not explain the susceptibility to celiac disease.

Prevalence and clinical characteristics of celiac disease in Downs syndrome in a US study

Celiac disease is an autoimmune gastrointestinal disorder characterized by mucosal atrophy of the jejunum on exposure to gluten, a protein found in grains. The purpose of our study was to determine the prevalence of celiac disease in children with Downs syndrome in a U.S.-based Caucasian population. The 97 Downs syndrome children were screened for celiac disease using serum IgA-anti-endomysial antibody testing, which is highly specific and sensitive for the disorder. Children with titers greater than 1:5 (using the IgA endomysial antibody [EMA] test; EMA+) were considered affected. Ten children (10.3%) were EMA+. We examined their HLA DQA1 DQB1 genotype, karyotype, clinical characteristics, and the prevalence of celiac disease in their first-degree relatives. The nine available karyotypes were trisomy 21. Downs syndrome-specific mean height percentile was 64%+/-26% (range <5-99%) and weight percentile was 43%+/-28% (range 5-95%). Presence of diarrhea, constipation, vomiting, and abdominal pain was similar for children with and without celiac disease. Only bloating symptoms were significantly more frequent in those with celiac disease (EMA+). Seven of eight (88%) genotyped EMA+ children had the celiac disease-associated high-risk HLA DQA1*0501 DQB1*0201 genotype as compared with 13/ 80 (16%) of EMA- children. Five of 48 (10%) first-degree relatives of the celiac disease (EMA+) children were EMA+. In conclusion, celiac disease, as diagnosed by positive endomysial antibody tests, has an increased prevalence in children with Downs syndrome in the U.S. as compared with the general population (1/250). Clinical and growth characteristics do not distinguish between children with and without celiac disease. Based on these observations, it is recommended that children with Downs syndrome be screened for celiac disease.

Postpericardiotomy syndrome: no evidence for a viral etiology

BACKGROUND

Postpericardiotomy syndrome has been considered a disorder induced by viral infection. This conclusion is based on serologic criterions, but these may be unreliable following either cardiopulmonary bypass or transfusion therapy. Previous studies have not verified the proposed etiology either by isolation of viruses, or by detection of their genome. We sought, therefore, to clarify the role, if any, of viruses in this syndrome.

METHODS AND RESULTS

We studied prospectively 149 children aged from 6 months to 16 years who were undergoing open heart surgery. Blood samples were collected from all prior to operation, and again 7 to 10 days post-operatively, and 47 were sampled at the time of development of symptoms of pericardial involvement. Serums were analyzed for the presence of IgM and IgG antibodies to cytomegalovirus, herpes simplex virus, and Epstein-Barr virus. The polymerase chain reaction was used for amplification when assessing the genome of the enteroviruses. Cultures for viruses were established on samples of stool, urine, and throat swabs collected 7 days post-operatively, and at the time of postpericardial symptoms. Pericardial fluid obtained from 5 patients with the syndrome was cultured for viruses, and tested for enterovirus genome. On the basis of clinical and echocardiographic findings, 34 children were determined to have definite evidence of the syndrome, 13 were considered to have possible evidence, and the results from these patients were compared to those from patients with no pericardial symptoms, the latter being matched for age and transfusion status. We isolated viruses from one or more sites in five patients with definite evidence (16%), from one (9%) of those with possible evidence, and from seven (19%) of the controls. All serums and pericardial samples were negative for enterovirus genome. IgM antibodies were found in only 5 patients, three with symptoms of pericardial involvement and two without. Rates of seroconversion to IgG for the viruses were lower in the patients with symptoms of pericardial involvement compared to controls, but were strongly influenced by transfusion status.

CONCLUSION

Our study has provided no evidence to support a viral etiology for the postpericardiotomy syndrome.

Celiac disease and human leukocyte antigen genotype: accuracy of diagnosis in self-diagnosed individuals, dosage effect, and sibling risk

BACKGROUND

Celiac disease is an autoimmune disorder of the small intestine characterized by intolerance to gluten. Traditionally, diagnosis is made by intestinal biopsy. Testing for immunoglobulin (Ig) A endomysial antibodies in the serum also is used for diagnosis. Biopsy and serology revert to normal with adherence to a gluten-free diet. Often, after an index case is diagnosed, siblings with symptoms adhere to a gluten-free diet without biopsy or serologic confirmation. More than 90% of patients with celiac disease have the human leukocyte antigen (HLA) DQA1*0501-DQB1*0201 genotype. Non-HLA genes also have been implicated.

METHODS

One hundred ninety-five individuals with confirmed or suspected celiac disease were identified in 73 families affected by the disease. IgA endomysial antibody testing was performed for all symptomatic family members who did not have biopsy-confirmed diagnoses. DNA samples were genotyped at D6S276 and the HLA class II loci DQA and DQB.

RESULTS

At the time sampling was begun in families, 88 of 177 (49.7%) individuals were self-diagnosed and adhering to a gluten-free diet. Ninety percent (91/101) of confirmed cases (biopsy or serology) had at least 1 copy of the DQA1*0501-DQB1*0201 genotype, whereas only 67% (46/69) of cases self-diagnosed (adherence to gluten-free diet without confirmation) had at least 1 copy. Of confirmed cases, 61% carried two copies of DQB*0201. It is estimated that the HLA association and other unlinked genes contribute approximately equally to the sibling risk of celiac disease.

CONCLUSIONS

A dosage effect of DQB1*0201 may be associated with an increased risk of celiac disease. Self-diagnosis of celiac disease is as common as confirmed diagnosis in families in the United States. Diagnosis of celiac disease on the basis of clinical response to gluten restriction is inaccurate. With long-term adherence to a gluten-free diet, serologic test results are likely to be negative. Based on HLA genotype, approximately one third of self-diagnosed individuals are unlikely to have celiac disease. However, it is not possible to determine which individuals consuming a gluten-free diet have the disease. Therefore, before starting a gluten-free diet, serologic screening and biopsy confirmation are necessary.

Treatment of pediatric autoimmune enteropathy with tacrolimus (FK506)

Autoimmune enteropathy is characterized by chronic secretory diarrhea, villous atrophy, associated autoantibodies, and a partial response to immunosuppression. Currently available therapy (including steroids and cyclosporine) has resulted in remission only in a subset of patients. We evaluated the effects of tacrolimus (FK506) in patients with autoimmune enteropathy refractory to steroids and cyclosporine. Three patients with diagnosed autoimmune enteropathy who continued to have intractable diarrhea despite treatment with steroids and/or cyclosporine were treated with oral tacrolimus. Despite documented histological villous atrophy and poor absorption of oral cyclosporine, therapeutic tacrolimus levels were easily achieved in all 3 patients. All patients showed clinical improvement as documented by decreased stool output and ability to be weaned off parenteral nutrition; response time ranged from 1 to 4 months after tacrolimus was begun. Histological improvement was noted in all patients, and the small bowel biopsy specimens of 2 of the 3 patients showed a return to normal. All patients have been followed up for at least 6 months and are in clinical remission; 1 has received a bone marrow transplant for underlying immunodeficiency. Tacrolimus is a useful drug in the treatment of autoimmune enteropathy, even in patients who have not responded to steroids or cyclosporine. No long-term follow-up of patients with autoimmune enteropathy treated with tacrolimus is currently available.

The utility of latex agglutination assays in the diagnosis of pediatric viral gastroenteritis

To design a rapid and efficient protocol for processing pediatric stool specimens, the authors used 434 specimens to evaluate two commercial latex assays to detect rotavirus (Meritec-Rotavirus and Rotalex) and one to detect adenovirus (Adenolex). Rotavirus latex assay results were compared with electron microscopic examination and adenovirus latex assay results with virus culture. Ninety-two specimens (21%) were positive for rotavirus and 28 (6.5%) for adenovirus; 5 (1%) had both viruses. The sensitivity, specificity, positive predictive values, and negative predictive values for the three assays were, respectively, as follows: Meritec-Rotavirus (97%, 99%, 97%, 99%), Rotalex (91%, 99%, 94%, 98%), and Adenolex (46%, 99%, 77%, 97%). For primary rotavirus screening, the Meritec-Rotavirus and Rotalex latex assays offer a good alternative to electron microscopic examination. For primary adenovirus screening, the low sensitivity of the Adenolex latex assay precludes its use as a routine screen. Its excellent specificity, however, makes it a useful tool for culture confirmation.

Serum alpha fetoprotein (AFP) levels in normal infants

Serum alpha-fetoprotein (AFP) levels were monitored in 32 normal babies consecutively from 2 to 3 days, 2 wk, and 2 and 4 months after birth. In addition, serum AFP concentration was also measured in 116 random specimens from infants with normal liver enzymes and 10 infants born immaturely. Results were combined to establish normal AFP levels for infants at various ages. Serum AFP disappeared rapidly after birth. We found that it was not until 8 months of age that the normal AFP level in infants approached adult level. The half-lives of AFP degradation were estimated to be 5.5 days between birth and 2 wk, 11 days between 2 wk to 2 months, and 33 days between 2 and 4 months of age. In contrast to earlier belief, we felt that some AFP synthesis still exists after birth; however, the rate of synthesis may also decrease with age.