Plasma microRNA levels in male and female children with cystic fibrosis

A gender gap exists in cystic fibrosis (CF). Here we investigate whether plasma microRNA expression profiles differ between the sexes in CF children. MicroRNA expression was quantified in paediatric CF plasma (n = 12; six females; Age range:1-6; Median Age: 3; 9 p.Phe508del homo- or heterozygotes) using TaqMan OpenArray Human miRNA Panels. Principal component analysis indicated differences in male versus female miRNA profiles. The miRNA array analysis revealed two miRNAs which were significantly increased in the female samples (miR-885-5p; fold change (FC):5.07, adjusted p value: 0.026 and miR-193a-5p; FC:2.6, adjusted p value: 0.031), although only miR-885-5p was validated as increased in females using specific qPCR assay (p < 0.0001). Gene ontology analysis of miR-885-5p validated targets identified cell migration, motility and fibrosis as processes potentially affected, with RAC1-mediated signalling featuring significantly. There is a significant increase in miR-885-5p in plasma of females versus males with CF under six years of age.

Successful long-term outcome of liver transplantation in late-onset lysosomal acid lipase deficiency

Late-onset LAL deficiency, previously referred to as cholesteryl ester storage disorder, is a rare lysosomal storage disorder characterized by accumulation of cholesteryl esters. It has a heterogeneous clinical phenotype including abdominal pain, poor growth, hyperlipidemia with vascular complications and hepatosplenomegaly. End-stage liver disease may occur, but there are few reports of successful LT. There are also concerns that systemic manifestations of the disease might persist post-LT. We report a case with excellent outcome eight yr following LT. The subject was noted to have asymptomatic hepatosplenomegaly during an intercurrent illness, and LAL deficiency was confirmed with compound heterozygosity in the LIPA. Despite dietary fat restriction, he developed signs of progressive liver disease and subsequently developed hepatopulmonary syndrome. He underwent cadaveric LT at the age of nine and a half yr and recovered with prompt resolution of hepatopulmonary syndrome. Eight yr post-transplant he has normal growth, normal lipid profile, and liver and renal function tests. Liver histology showed no evidence of disease recurrence at this stage. LT in this subject resulted in an excellent functional correction of late-onset LAL deficiency.

Outcome of children with hereditary tyrosinaemia following newborn screening

BACKGROUND

Nitisinone has transformed the management of hereditary tyrosinaemia type 1 (HT1). However, the risk of developing hepatocellular carcinoma is related to the age at which treatment is commenced. Little data on the outcome of children treated pre-emptively exist.

AIM

To describe the outcome of children with HT1 treated with nitisinone following selective newborn screening (NBS) and to compare their outcome with index siblings who had presented clinically.

SUBJECTS

12 children with HT1 were detected by NBS. Seven children were screened for HT1 because of an affected sibling (n=5). Four children were detected due to raised tyrosine concentrations on routine NBS and one child was born in a country with universal NBS for HT1.

OUTCOME

Nitisinone was commenced at 4 (1-52) days old. 6 children had an initial coagulopathy which resolved after 4 (1-7) days treatment. Currently at median age 8.5 (3-12.5) years all are clinically normal, with normal liver function tests and imaging. Those of school age are in normal classes but four have reported learning difficulties. Five index siblings presented clinically with acute liver failure (four) and chronic liver disease (one) at median 4 (1.5-17) months. One died of liver failure prior to nitisinone's availability. Four were treated with nitisinone; one failed to respond and underwent liver transplantation and three responded. One responder died from complications of prematurity and the remaining two have compensated liver disease.

SUMMARY

Children with HT1 treated with nitisinone following NBS have an excellent outcome.

CONCLUSIONS

Universal NBS for HT1 should be introduced in the UK.

Rejection is less common in children undergoing liver transplantation for hepatoblastoma

To compare the incidence of acute histologically proven rejection in children who have had a liver transplant for hepatoblastoma with a control group of children transplanted for biliary atresia (EHBA). A retrospective case notes based study was performed. Twenty patients were identified with hepatoblastoma who were transplanted at a single unit between 1991 and 2008. These were matched as closely as possible for age, gender, year of transplant and type of immunosuppression used to the control group transplanted for biliary atresia (n = 60). There was a significant decrease in rate of acute rejection as assessed by the rejection activity index (RAI) in the hepatoblastoma group (75% vs. 50%, respectively, p < 0.04). Chronic rejection was rare in both groups, but twice as common in the biliary atresia group. Equal levels of immunosuppression were achieved in both groups. Renal function was noted to be reduced one yr post-transplant in both groups, as previously reported. A modified immunosuppression regimen could be considered in children with hepatoblastoma undergoing liver transplantation.

Successful isolated liver transplantation in a child with atypical hemolytic uremic syndrome and a mutation in complement factor H

A male infant was diagnosed with atypical hemolytic uremic syndrome (aHUS) at the age of 5.5 months. Sequencing of the gene (CFH) encoding complement factor H revealed a heterozygous mutation (c.3644G>A, p.Arg1215Gln). Despite maintenance plasmapheresis he developed recurrent episodes of aHUS and vascular access complications while maintaining stable renal function. At the age of 5 years he received an isolated split liver graft following a previously established protocol using pretransplant plasma exchange (PE) and intratransplant plasma infusion. Graft function, renal function and disease remission are preserved 2 years after transplantation. Preemptive liver transplantation prior to the development of end stage renal disease is a valuable option in the management of aHUS associated with CFH mutations.

Reversible valproate hepatotoxicity due to mutations in mitochondrial DNA polymerase γ (POLG1)

We report the case of a 2-year-old boy with seizures who developed hepatic failure shortly after commencing sodium valproate. Unexpectedly, liver function returned to normal on stopping the drug. Sequencing of the mitochondrial polymerase γ gene (POLG1) revealed four heterozygous substitutions, two of which have been identified in cases of Alpers-Huttenlocher disease.

Renal tubular function in children with tyrosinaemia type I treated with nitisinone

BACKGROUND

Tyrosinaemia type I (TTI) is an inherited deficiency in the enzyme fumarylacetoacetate hydrolase and is frequently complicated by renal tubular dysfunction which may persist in some patients after hepatic transplantation. Nitisinone has revolutionized the management of TTI but its effect on renal tubular dysfunction has not been described in a large cohort of patients.

AIMS

To document the incidence and progression of renal tubular dysfunction in children with TTI treated with nitisinone at a single centre.

SUBJECTS

Twenty-one patients with TTI from a single centre were treated with nitisinone for at least 12 months. Median age at first treatment was 17 weeks (range 1 week to 27 months). Nine patients (43%) presented in acute liver failure, seven (33%) had a chronic presentation and five (24%) were detected pre-clinically.

METHODS

A retrospective case analysis of plasma phosphate, urinary protein/creatinine ratio and tubular reabsorption of phosphate was performed for all patients as markers of tubular function. Renal ultrasounds were examined for evidence of nephrocalcinosis and where available, skeletal radiographs for rickets.

RESULTS

All patients had biochemical evidence of renal tubular dysfunction at presentation. After nitisinone and dietary treatment were started, all three markers normalized within one year. Four children had clinical rickets at presentation (which improved), of whom one had nephrocalcinosis, which did not reverse on nitisinone. No child redeveloped tubular dysfunction after commencing nitisinone. All patients with TTI had evidence of tubular dysfunction at presentation and in all cases this resolved with nitisinone and dietary control.

CONCLUSION

The tubulopathy associated with TTI is reversible.

Reversible valproate hepatotoxicity due to mutations in mitochondrial DNA polymerase gamma (POLG1)

We report the case of a 2-year-old boy with seizures who developed hepatic failure shortly after commencing sodium valproate. Unexpectedly, liver function returned to normal on stopping the drug. Sequencing of the mitochondrial polymerase gamma gene (POLG1) revealed four heterozygous substitutions, two of which have been identified in cases of Alpers-Huttenlocher disease.

The usefulness of bone marrow aspiration in the diagnosis of Niemann-Pick disease type C in infantile liver disease

BACKGROUND

Niemann-Pick disease type C (NPC) is a fatal, autosomal recessive lysosomal storage disease which may present in infancy with cholestatic jaundice and/or hepatosplenomegaly. In cholestatic patients with splenomegaly, a bone marrow aspirate has been advocated as a relatively accessible tissue to demonstrate storage phenomena. Typically in patients with NPC, macrophages with abnormal cholesterol storage, so called foam cells, can be detected in the bone marrow.

AIM

To review our experience of bone marrow aspiration in children with NPC presenting with infantile liver disease.

METHODS

A retrospective analysis of 11 consecutive children (8 males) from Birmingham Children's Hospital with NPC presenting with infantile liver disease was undertaken. The diagnosis of NPC was confirmed in all cases by demonstrating undetectable or low rates of cholesterol esterification and positive filipin staining for free cholesterol in cultured fibroblasts.

RESULTS

The median age at presentation was 1.5 months (range 0.5-10). Bone marrow aspirates showed storage cells in only 7/11 cases. Bone marrow aspirates which had storage cells were undertaken at a median age of 11 months while those with no storage cells were undertaken at median age 2.3 months. The overall sensitivity of bone marrow aspirates for detecting storage cells in children presenting with infantile liver disease was 64%; however, for children who had bone marrow aspirates in the first year of life it was only 57%.

CONCLUSIONS

The sensitivity of bone marrow aspirate for the diagnosis of NPC disease in patients presenting with infantile liver disease was lower than previously reported. Where NPC is suspected clinically, definitive investigations should be undertaken promptly. There is a need to develop sensitive screening methods for NPC in children presenting with infantile liver disease.

Is Serum Gentamicin Level a Good Predictor of Graft Injury in Intestinal Transplantation?

INTRODUCTION

Following intestinal transplant (SBT), the early diagnosis and treatment of rejection is a major management aim. The diagnosis of rejection is based on histology of stomal biopsies. Oral gentamycin (2.5 mg/kg) was used for selective decontamination of the digestive system. Our hypothesis was that gentamycin might be absorbed in the presence of graft dysfunction.

AIM

Our goal was to assess the correlation between serum gentamycin level and the health of the intestinal graft.

SUBJECTS AND METHODS

Among 33 SBT performed from 1993 to 2005, serum gentamycin levels were performed once weekly or more often when there was a suspicion of rejection. All data were analyzed retrospectively.

RESULTS

Adequate trough levels were achieved for only 23 patients, six of whom had histologically proven rejection and only one did not have a raised gentamycin content. Five patients with raised levels but no rejection included two with severe intestinal ischemia and three with bowel obstruction/ileus. Four of the five patients required laparotomies.

CONCLUSION

We concluded that in our study raised serum gentamycin levels were a good predictor of rejection or significant injury to the graft.

Paracetamol induced hepatotoxicity

AIM

To identify the clinical and biochemical risk factors associated with outcome of paracetamol induced significant hepatotoxicity in children.

METHODS

Retrospective case notes review of those with paracetamol overdose admitted from 1992 to 2002. Patients were analysed in two groups: group I recovered after conservative treatment and group II developed progressive liver dysfunction and were listed for liver transplantation.

RESULTS

Of 51 patients (6 males, 45 females, aged 0.8-16.1 years), 6 (aged <7 years) received cumulative multiple doses, and 45 a single large overdose (median 345 mg/kg, range 91-645). The median (range) interval to hospital at presentation post-ingestion was 24 hours (4-65) and 44 hours (24-96) respectively in groups I and II. Patients received standard supportive treatment including N-acetylcysteine. All children in group I survived. In group II, 6/11 underwent orthotopic liver transplantation (OLT) and 2/6 survived; 5/11 died awaiting OLT. Cerebral oedema was the main cause of death. Children who presented late to hospital for treatment and those with progressive hepatotoxicity with prothrombin time >100 seconds, hypoglycaemia, serum creatinine >200 micromol/l, acidosis (pH <7.3), and who developed encephalopathy grade III, had a poor prognosis or died. Although hepatic transaminase levels were markedly raised in both groups, there was no correlation with necessity for liver transplantation or death.

CONCLUSION

Accidental or incidental paracetamol overdose in children may be associated with toxic liver damage leading to fulminant liver failure. Delayed presentation and/or delay in treatment, and hepatic encephalopathy > or =grade III were significant risk factors, implying poor prognosis and need for OLT. Prompt identification of high risk patients, referral to a specialised unit for management, and consideration for liver transplantation is essential.

Cardiomyopathy in tyrosinaemia type I is common but usually benign

Tyrosinaemia type I (TTI) is an inherited multisystemic disorder of tyrosine metabolism. In addition to hepatic and renal involvement, cardiomyopathy is an important clinical manifestation.

OBJECTIVE

To evaluate the incidence and outcome of cardiomyopathy in TTI.

SUBJECTS AND METHODS

A retrospective study was performed of 20 consecutive children with TTI (12 male, 8 female) referred to a single centre between 1986 and 2002. All were initially treated with standard dietary therapy and, since 1992, with nitisinone. The indications for orthotopic liver transplantation (LT) changed during the study. Serial echocardiography was undertaken in all subjects.

RESULTS

9/20 (45%) children had an acute hepatic presentation. Five (25%) received dietary treatment followed by LT, and 14 (70%) were treated with nitisinone at presentation. 6/20 (30%) had cardiomyopathy at initial assessment, with interventricular septal hypertrophy being the commonest finding (5/6). Cardiomyopathy was significantly less common in those treated initially with nitisinone. After a median follow-up of 3.6 (0.45-13.5) years, 5/6 (83%) had complete resolution of cardiomyopathy and 1/6 showed significant improvement. No child with a normal initial echocardiography subsequently developed cardiomyopathy.

CONCLUSION

Cardiomyopathy is a common manifestation of TTI and it has a favourable long-term outcome. Children initially treated with nitisinone are less likely to develop this complication.

POLGmutations in Alpers syndrome

Described are six patients with Alpers syndrome from four unrelated families. Affected individuals harbored the following combinations of POLG mutations: 1) A467T/W1020X, 2) W748S-E1143G/G848S, 3) A467T/A467T, and 4) A467T/G848S. Homozygosity for the A467T allele in one patient was associated with a later age at onset. Mitochondrial respiratory chain studies in skeletal muscle were normal in each case. Nine combinations of mutant POLG alleles that cause Alpers syndrome are summarized.

Hyperinsulinism in tyrosinaemia type I

Tyrosinaemia type I (TT I) (McKusick 276700) is a heterogeneous disorder with a broad spectrum of clinical phenotypes. Although histological abnormalities of the pancreas are well recognized, there are only incidental reports of pancreatic dysfunction manifested as insulin-dependent diabetes mellitus. We report three subjects with TT I and acute liver dysfunction who had hyperinsulinism in early infancy. Hypoglycaemia persisted despite dietary treatment and one patient had inadequate lipolysis at the time of hypoglycaemia. All three patients were successfully treated with diazoxide (10 mg/kg per day) and chlorthiazide (35 mg/kg per day) and treatment was gradually withdrawn after 9, 13 and 34 months, respectively. The mechanism of pancreatic dysfunction in TT I is unknown but may be related to the toxic metabolites that accumulate in this condition. We conclude that hyperinsulinism is not a rare complication in TT I. In patients with persistent hypoglycaemia, C-peptide should always be measured. Treatment with diazoxide and chlorthiazide is highly effective, appears to be safe, and does not need to be continued lifelong.

Renal function following liver transplantation for unresectable hepatoblastoma

Combination of cyclosporine (CsA) and tacrolimus immunosuppression post-liver transplantation (LT) and the chemotherapeutic drugs used to treat hepatoblastoma (HB), are nephrotoxic. We aimed to determine the severity and duration of nephrotoxicity in children following LT for unresectable HB. We reviewed all children undergoing LT for unresectable HB at the Liver Unit, Birmingham Children's Hospital, UK, from 1991 to July 2000. Thirty-six children undergoing LT for biliary atresia, matched for age and sex, were selected as controls to compare pre- and post-LT renal function. Renal function was determined by estimation of glomerular filtration rate (eGFR) derived from plasma creatinine using Schwartz's formula. Twelve children with HB (mean age of diagnosis 33 months) who underwent LT (mean age 47 months) and 36 controls (mean age of LT 34 months) were studied. CsA was the main immunosuppressive drug used in each group. The median eGFR before, and at 3, 6, 12, 24 and 36 months after LT in HB group was significantly lower than controls (93 vs. 152, 66 vs. 79, 62 vs. 86, 66 vs. 87, 64 vs. 94, 53 vs. 90 mL/min/1.73 m2, respectively; 0.01 < p < 0.03). The reductions in the median eGFR of both the HB group and controls before and at 36 months after LT were 49 and 41%, respectively. At 36 months after LT, there was a trend for partial recovery of the eGFR in the controls but not in the HB group. Children who underwent LT for unresectable HB had renal dysfunction before transplantation that persisted for 36 months after LT.

Ophthalmic follow-up of patients with tyrosinaemia type I on NTBC

NTBC has revolutionized the management of tyrosinaemia type I, although animal experiments have shown that long-term administration may produce corneal opacities analogous to those in tyrosinaemia type II. We have assessed the prevalence of ocular side-effects in 11 tyrosinaemia type I patients on NTBC attending the Birmingham Children's Hospital. Despite high plasma tyrosine concentrations in some patients, they did not experience symptoms or signs of ocular toxicity.

Concomitant basiliximab with low-dose calcineurin inhibitors in children post-liver transplantation

Orthotopic liver transplantation (OLT) is effective therapy for end-stage liver disease but immunosuppression with calcineurin inhibitors (CNI) leads to significant nephrotoxicity, resulting in either a reduction of dosage to below the therapeutic level or omission of the drug altogether. Basiliximab (Bx) is a human/mouse chimeric monoclonal antibody that inhibits binding of interleukin-2 (IL-2) to IL-2 receptors and thus prevents proliferation of T cells, which is the main step in the development of acute cellular rejection. The aim of this study was to identify the role of Bx in the prevention of acute cellular rejection and in the reduction of nephrotoxicity in children post-liver transplantation. We evaluated three children (19 months, 22 months, and 11 yr of age; one male, two female) who were treated with Bx post-OLT on compassionate grounds. The indications were: nephrotoxicity in two children, requiring re-transplantation for hepatic artery thrombosis and recurrent giant cell hepatitis, respectively; and nephrotoxicity secondary to chemotherapy for hepatoblastoma in the third child. All patients received 10 mg of Bx, at OLT and on Day 4. Tacrolimus (0.15 mg/kg/day) was started at 48 h (n = 2) and cyclosporin (5 mg/kg/day) at 2 weeks (n = 1). Trough levels of tacrolimus were maintained at 5-8 ng/mL and trough levels of cyclosporin at 100-150 mg/L for the first 3 months. All patients received methylprednisolone (2 mg/kg) with azathioprine (1.5 mg/kg) (n = 2) and/or mycophenolate mofetil (20 mg/kg) (n = 1). The glomerular filtration rate (cGFR) was calculated using the Schwartz formula before and 10 weeks after transplant. Bx was found to be easy to administer and no major side-effects were reported. One child had two episodes of mild acute rejection at 5 and 9 weeks post-OLT and one developed chronic rejection requiring re-transplantation at 9 weeks post-OLT. One child did not develop rejection. The mean pretransplant cGFR was 58.1 (54.6-64.1) mL/min/m2. Within 10 weeks of transplantation, the cGFR had improved by 69% to a mean of 116 (88-157.6) mL/min/m2. To conclude, Bx was well tolerated in all children and had a renal sparing effect. It was effective in preventing early acute rejection, but the combination of Bx and low-dose CNI drugs did not prevent late acute or chronic rejection. Further studies to evaluate the appropriate levels of CNI immunosuppression with Bx are required.

Neonatal cholestasis

Neonatal cholestasis must always be considered in a newborn who is jaundiced for more than 14-21 days and a measurement of the serum total and conjugated bilirubin in these infants is mandatory. Conjugated hyperbilirubinaemia, dark urine and pale stools are pathognomic of the neonatal hepatitis syndrome which should be investigated urgently. The neonatal hepatitis syndrome has many causes and should be investigated using a structured protocol. The most important condition in the differential diagnosis is biliary atresia and affected infants require a Kasai portoenterostomy performed by an experienced surgeon, ideally before the infant is 60 days old. A modified evaluation schedule should be used for preterm infants who have required neonatal intensive care. Genetic causes of the neonatal hepatitis syndrome are increasingly recognized and early diagnosis facilitates genetic counselling and, in some situations, specific treatment. The management of cholestasis is largely supportive, consisting of aggressive nutritional support with particular attention to fat-soluble vitamin status. The use of ursodeoxycholic acid is associated with improvement in biochemical measures of cholestasis and may improve the natural history of cholestasis in some circumstances. Outcome is dependent on aetiology. In idiopathic neonatal hepatitis more than 90% make a complete biochemical and d clinical recovery.

Techniques for and outcome of liver transplantation in neonates and infants weighing up to 5 kilograms

BACKGROUND

Neonates and small infants represent less than 5% of paediatric candidates for liver replacement. Most cases present under urgent conditions and receive grafts from large donors. Surgical techniques must be adapted for adequate graft preparation, vascular reconstruction, and abdominal closure.

METHODS

Technical aspects and outcome of 15 liver transplantations in infants weighing less than 5 kg performed at our unit were analysed retrospectively.

RESULTS

Liver transplantation was performed under urgent or highly urgent condition in 13 cases. Reduced or split liver grafts were used in all cases (median donor to recipient weight ratio, 9), including a monosegmental graft in 2 cases. In 10 cases, vascular reconstruction was done using a vascular conduit (5, 4, and 1 for artery, portal, and hepatic veins, respectively) and a delayed closure of the abdomen was necessary in 7 children. Postoperative complications were as follows: thrombosis of hepatic artery (n = 1) or portal vein (n = 1), gastrointestinal haemorrhage (n = 2), intraperitoneal bleeding (n = 1), biliary stricture (n = 2), septicaemia (n = 1). Two infants died of brain damage with a functioning graft. One child underwent retransplant for chronic rejection.

CONCLUSIONS

Overall, survival rate is 60% (median follow-up, 34 months), which compares favourably with older patient groups when case mix is comparable.

Metabolic stroke in methylmalonic acidemia five years after liver transplantation

It is believed that liver transplantation may improve the outcome of early onset methylmalonic acidemia. We report a case of methylmalonic acidemia in which successful liver transplantation in infancy failed to prevent neurologic damage caused by a metabolic stroke.

Successful treatment of refractory ascites in a child with transjugular intrahepatic portosystemic shunt

A 16-y-old boy who had undergone bone marrow transplantation for relapsed acute lymphoblastic leukaemia developed liver cirrhosis and refractory ascites, which did not respond to salt restriction, diuretics and abdominal paracentesis. Liver transplantation was not feasible because of poor nutritional status, pre-existing renal dysfunction and uncertainty about the prognosis of his leukaemia. The patient underwent a successful transjugular intrahepatic portosystemic shunt (TIPS), with immediate resolution of ascites, enabling cessation of diuretics and improvement in nutritional status. At 24 mo following TIPS there has been no re-accumulation of ascites.

CONCLUSION

TIPS may have a role in the management of refractory ascites secondary to liver cirrhosis in selected children.

ARC syndrome: an expanding range of phenotypes

AIM

To describe the clinical phenotype in infants with ARC syndrome, the association of arthrogryposis, renal tubular acidosis, and cholestasis.

METHODS

The medical records for six patients with ARC syndrome were reviewed, presenting over 10 years to three paediatric referral centres.

RESULTS

All patients had the typical pattern of arthrogryposis. Renal Fanconi syndrome was present in all but one patient, who presented with nephrogenic diabetes insipidus. Although all patients had severe cholestasis, serum gamma glutamyltransferase values were normal. Many of our patients showed dysmorphic features or ichthyosis. All had recurrent febrile illnesses, diarrhoea, and failed to thrive. Blood films revealed abnormally large platelets.

CONCLUSIONS

ARC syndrome exhibits notable clinical variability and may not be as rare as previously thought. The association of Fanconi syndrome, ichthyosis, dysmorphism, jaundice, and diarrhoea has previously been reported as a separate syndrome: our observations indicate that it is part of the ARC spectrum.

Complete regression of posttransplant lymphoproliferative disease using partially HLA-matched Epstein Barr virus-specific cytotoxic T cells

BACKGROUND

Adoptive immunotherapy with autologous and donor-derived cytotoxic T lymphocytes (CTL) has recently been used to treat Epstein Barr virus (EBV)-positive posttransplant lymphoproliferative disease (PTLD).

METHODS AND RESULTS

We report complete regression of EBV-positive PTLD in an 18-month-old small bowel and liver transplant recipient after one infusion of partially human leukocyte antigen (HLA)-matched EBV-specific CTL grown ex vivo from an EBV seropositive unrelated blood donor. No infusion-related toxicity or evidence of graft-versus-host disease was observed. The tumor showed signs of regression within 1 week and EBV load in peripheral blood dropped to undetectable levels. Limiting dilution analyses (LDA) detected no EBV-specific CTL precursor (CTLp) cells before the infusion, and high numbers of CTLp at 4 hr and 24 hr post-CTL infusion. There was a reversal of the CD4/8 ratio in peripheral blood and an increase in HLA-DR positive CD8 cells. The patient has been in complete remission for 24 months.

CONCLUSION

If this success is repeated in more PTLD patients, then stored CTL could be used for antiviral and antitumor therapies in immunocompromised patients.

Treatment of variceal bleeding

Variceal bleeding is the most common cause of severe gastro-intestinal bleeding in childhood. Biliary atresia and portal venous obstruction are the most common causes. Each center should have a defined management protocol reflecting local practice and expertise. For patients with acute bleeding, pharmacotherapy with octreotide should be used immediately. All of these patients should undergo therapeutic endoscopy with band ligation or sclerotherapy. All children surviving variceal hemorrhage should undergo secondary prophylaxis with band ligation. No evidence supports the routine use of primary prophylaxis in children with esophageal varices.

Classification and genetic features of neonatal haemochromatosis: a study of 27 affected pedigrees and molecular analysis of genes implicated in iron metabolism

Neonatal haemochromatosis (NH) is a severe and newly recognised syndrome of uncertain aetiology, characterised by congenital cirrhosis or fulminant hepatitis and widespread tissue iron deposition. NH occurs in the context of maternal disease including viral infection, as a complication of metabolic disease in the fetus, and sporadically or recurrently, without overt cause, in sibs. Although an underlying genetic basis for NH has been suspected, no test is available for predictive analysis in at risk pregnancies. As a first step towards an understanding of the putative genetic basis for neonatal haemochromatosis, we have conducted a systematic study of the mode of transmission of this disorder in a total of 40 infants born to 27 families. We have moreover carried out a molecular analysis of candidate genes (beta(2)-microglobulin, HFE, and haem oxygenases 1 and 2) implicated in iron metabolism. No pathogenic mutations in these genes were identified that segregate consistently with the disease phenotype in multiplex pedigrees. However, excluding four pedigrees with clear evidence of maternal infection associated with NH, a pedigree showing transmission of maternal antinuclear factor and ribonucleoprotein antibodies to the affected infants, and two families with possible matrilineal inheritance of disease in maternal half sibs, a large subgroup of the affected pedigrees point to the inheritance of an autosomal recessive trait. This included 14 pedigrees with affected and unaffected infants and a single pedigree where all four affected infants were the sole offspring of consanguineous but otherwise healthy parents. We thus report three distinct patterns of disease transmission in neonatal haemochromatosis. In the differentiation of a large subgroup showing transmission of disease in a manner suggesting autosomal recessive inheritance, we also provide the basis for further genome wide studies to define chromosomal determinants of iron storage disease in the newborn.

Bile bilirubin pigment analysis in disorders of bilirubin metabolism in early infancy

BACKGROUND

Early and accurate diagnosis of Crigler-Najjar syndrome, which causes prolonged unconjugated hyperbilirubinaemia in infancy, is important, as orthotopic liver transplantation is the definitive treatment.

AIM

To determine whether bilirubin pigment analysis of bile in infants with prolonged unconjugated hyperbilirubinaemia provides useful diagnostic information in the first 3 months of life.

METHODS

Retrospective review of patients with prolonged unconjugated hyperbilirubinaemia referred to the liver unit, Birmingham Children's Hospital, for the diagnosis of Crigler-Najjar syndrome. Bile bilirubin pigment composition was determined by high performance liquid chromatography. Initial diagnoses were made based on the result of bile bilirubin pigment composition. Final diagnoses were made after reviewing the clinical course, response to phenobarbitone, repeat bile bilirubin pigment composition analysis, and genetic studies.

RESULTS

Between 1992 and 1999, nine infants aged less than 3 months of age with prolonged hyperbilirubinaemia underwent bile bilirubin pigment analyses. Based on these, two children were diagnosed with Crigler-Najjar syndrome (CNS) type 1, six with CNS type 2, and one with Gilbert's syndrome. Five children whose initial diagnosis was CNS type 2 had resolution of jaundice and normalisation of serum bilirubin after discontinuing phenobarbitone, and these cases were thought to be normal or to have Gilbert's syndrome. One of the initial cases of CNS type 1 responded to phenobarbitone with an 80% reduction in serum bilirubin consistent with CNS type 2. In all, the diagnoses of six cases needed to be reviewed.

CONCLUSIONS

Early bile pigment analysis, performed during the first 3 months of life, often shows high levels of unconjugated bilirubin or bilirubin monoconjugates, leading to the incorrect diagnosis of both type 1 and type 2 Crigler-Najjar syndrome.

The management of organic acidaemias: the role of transplantation

This workshop addressed the issue of treatment in propionic acidaemia (PA) and methylmalonic acidaemia (MMA) and in particular the outcome of conventional management compared with organ transplantation. Although it appears that with medical treatment the mortality for early-onset disease has improved, long-term outcome remains poor. However, liver and liver/kidney transplantation is associated with a high perioperative mortality and long-term complications. It offers only a partial cure. The indications for transplantation remain unclear. It is recommended that a register of PA and MMA patients should be established.

Combined liver-kidney transplantation for primary hyperoxaluria type 1 in young children

BACKGROUND

Primary hyperoxaluria type 1 (PH1) is a rare condition in which deficiency of the liver enzyme alanine:glyoxylate aminotransferase leads to renal failure and systemic oxalosis. Combined liver-kidney transplantation (LKT) is recommended for end-stage renal failure (ESRF) in adults, but management of infants and young children is controversial. We retrospectively reviewed six children who underwent LKT for PH1.

METHODS

The median age at diagnosis was 1.8 years (range 3 weeks to 7 years). Two children presented with severe infantile oxalosis at 3 and 9 weeks, five patients had ESRF with nephrocalcinosis and systemic oxalosis, (median duration of dialysis 1.3 years), and one had progressive chronic renal failure. Four children underwent combined LKT, one child staged liver then kidney, and one infant had an isolated liver transplant. The median age at transplantation was 8.9 years (range 1.7-15 years).

RESULTS

Overall patient survival was four out of six. The two infants with PH1 and severe systemic oxalosis died (2 and 3 weeks post-transplant) due to cardiovascular oxalosis and sepsis. The other four children are well at median follow-up of 10 months (range 6 months to 7.4 years). No child developed hepatic rejection and all have normal liver function. Renal rejection occurred in three patients. Despite maximal medical management, oxalate deposits recurred in all renal grafts, contributing to graft loss in one (one of the infants who died), and significant dysfunction requiring haemodialysis post-transplant for 6 months.

CONCLUSIONS

LKT is effective therapy for primary oxalosis with ESRF but has a high morbidity and mortality rate in children who present in infancy with nephrocalcinosis and systemic oxalosis. We feel that earlier LKT, or pre-emptive liver transplantation, may be a better therapeutic strategy to improve the outlook for these patients.

Characterization of a highly divergent TT virus genome

A novel TT virus (TTV)-like DNA sequence was detected in the serum of a patient (PM) with acute non-A-E hepatitis. The full-length genome sequence, referred to here as PM virus (PMV), was obtained and its relationship to other full or near full-length TTV sequences examined. Although it shares a common genomic arrangement and short conserved regions, the majority of the genome is extremely divergent, displaying an average genetic distance of 0.60 from all other TTV sequences. By comparing PMV with TTV genomes representing the most divergent types so far described, six major groups can be distinguished. The level of genetic diversity seen between these genomes is higher than would be expected within a single virus species. Indeed, PMV could be considered the prototype of an independent taxonomic group within the Circoviridae: family. A genoprevalence study of sera from blood donors and patients with acute hepatitis suggests that PMV is rare.

En block combined reduced-liver and small bowel transplants: from large donors to small children

BACKGROUND

The critical shortage of size-matched donor organs for infants and small children in need of combined liver and intestinal transplantation has lead to long waiting times and a high risk of dying before transplantation. Utilizing grafts from larger donors could alleviate this problem, but using larger composite grafts in small children has been challenging and unsuccessful in the past.

METHODS

We conducted a pilot study for evaluating the results of transplanting into small recipients a composite graft (reduced-size liver and whole small bowel, including duodenum and pancreas head) procured from large donors. Liver size reduction was performed ex situ using the extrahilar approach, which leaves the liver hilum untouched. Straightforward implantation of the graft was performed by simple, two-step vascular anastomoses. The preservation of the donor duodenum in continuity with the combined graft avoided the need for biliary reconstruction, thus preserving maximal bowel length for gut continuity restoration in the recipient.

RESULTS

Two children, weighing 7.6 and 9.8 kg, respectively, underwent transplantation of a composite graft procured from donors weighing 35 kg. Their waiting time (68 and 97 days, respectively) was shorter compared with our previous experience with conventional techniques. Both are currently alive and well, at home and on full enteral feeds, 15 and 11 months after transplantation, respectively.

CONCLUSION

This new technique has extended the range of possible donors for small candidates waiting for combined grafts and was successful in two patients. It should be considered for small recipients in the future.

The frequency and outcome of biliary atresia in the UK and Ireland

BACKGROUND

Biliary atresia is an obliterative cholangiopathy of infancy that is fatal if untreated. Surgical treatment, the Kasai portoenterostomy, may restore bile flow and clear jaundice, and, if successful, achieve a 10-year survival of 90% with a native liver. The outcome of a 2-year cohort of children with biliary atresia in the UK and Ireland was assessed to find the current frequency, the factors influencing outcome, and the medium-term need for liver transplantation.

METHODS

Cases diagnosed between March, 1993, and February, 1995, were notified by paediatricians to the British Paediatric Surveillance Unit via a monthly reporting system. Confirmed cases were followed up by postal questionnaires to notifying paediatricians.

FINDINGS

93 cases were confirmed, a frequency of 1/16700 livebirths. Primary surgery was done in 91 children in 15 surgical centres with an early success rate for clearing jaundice of 55% overall. Centres were grouped according to caseload; group A had more than 5 cases/year and group B fewer than 5 cases/year. Early success was higher in group-A centres, odds ratio 2.02 (95% CI 0.86-4.73), but this did not reach statistical significance. Of 41 children in whom surgery was unsuccessful in clearing jaundice 9 (22%) died and 30 (73%) underwent liver transplantation. Survival without liver transplantation and overall survival were both significantly greater in group-A centres, rate ratios 0.48 (95% CI 0.27-0.86) and 0.32 (0.11-0.94). Actuarial 5-year survival without transplantation was 61.3% in group-A centres and 13.7% in groupB centres. Actuarial 5-year overall survival was 91.2% in group A and 75% in group B. Once centre size was taken into account, no other factor, including age at surgery, was predictive of survival without transplantation or overall survival.

INTERPRETATION

The outcome of children with biliary atresia is related to the caseload of the surgical centre where they have their primary surgery. Children with biliary atresia should be managed in surgical centres with a caseload of more than five cases annually.

Liver transplantation for methylmalonic acidaemia

The outcome for children with severe forms of methylmalonic acidaemia remains poor. Patients have recurrent episodes of metabolic decompensation; many have neurodevelopmental complications and the mortality is high. Long-term survivors develop chronic renal failure. Because of the poor prognosis, transplantation has been considered. In young patients with early onset disease, liver transplantation might prevent complications and, for those in end-stage renal failure, kidney transplantation could be combined with that of the liver. The results of liver transplantation in the early onset patients have generally been disappointing. In particular there appears to be a high risk of neurological complications. The optimal management of those in end-stage renal failure has not yet been determined although combined liver and kidney transplantation has been successful.

CONCLUSION

The role of transplantation in methylmalonic acidaemia has yet to be established and follow up of all patients who are considered for transplantation is essential.

Metabolic liver disease in the pediatric patient

Most metabolic liver diseases that affect pediatric patients present in the neonatal period with either cholestasis or acute liver failure. Metabolic liver disease in the older child has considerable overlap with adult patients. New diagnostic methods and therapy, including liver transplantation, has radically changed the outcome of many metabolic liver diseases.

Metabolism of paracetamol in children with chronic liver disease

OBJECTIVE

To study the metabolism of single doses of paracetamol in paediatric patients with chronic liver disease admitted to a hospital liver disease clinic.

RESULTS

Thirteen paediatric patients, aged 7 months to 12 years, with chronic liver disease of varying severity were studied. In these children, paracetamol elimination half-life was negatively correlated with serum albumin and positively with prothrombin time, as previously reported in adults with liver disease. The rate constant of glucuronide formation was higher in the children with liver disease compared to the value reported in healthy children of similar ages. The rate constant of the formation of paracetamol sulphate was no different from that in normal children. The 36 h urinary paracetamol glucuronide to sulphate ratio was 1.4 (95% CI 0.8 to 1.7). This mean ratio was higher than in healthy children (0.81 and 0.75) but not significantly so, probably because of a Type 1 error due to the inevitable small sample size arising from the nature of the population being studied.

CONCLUSION

The present study provides reassuring additional data to indicate that, at least for single doses, there is no cause for concern in the use of paracetamol in children with chronic liver disease.

Nutritional care and candidates for small bowel transplantation

Twenty two children were evaluated for small bowel transplantation between 1989 and 1994. Eight were unfit for transplantation and died within three months; a raised plasma bilirubin concentration (> 200 mumol/l) predicted death from liver failure within six months (p = 0.0001). The 11 children who were not managed by a multidisciplinary nutritional care team were less well nourished at referral, had more complications with intravenous feeding catheters, and greater early mortality while awaiting transplantation (p < 0.05). It is recommended that children with chronic intestinal failure be referred for assessment early, before liver dysfunction is established.

Assay of paracetamol and its metabolites in urine, plasma and saliva of children with chronic liver disease

A high-performance liquid chromatographic (HPLC) assay of paracetamol and its metabolites is described. The method for quantifying the metabolism of paracetamol in children with chronic liver disease and the good correlation between plasma and salivary concentrations of paracetamol is demonstrated. Despite an increasing bias between the two methods with increasing concentration of paracetamol, it is concluded that salivary assay is satisfactory for characterising paracetamol pharmacokinetics in the group of patients studied.