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Mei-Hwei Chang

Publications and source records attributed to Mei-Hwei Chang.

At least 19 recordsLinked to original sources
PubMed2006

Impaired T-lymphocyte proliferation function in biliary atresia patients with chronic cholestatic jaundice after a Kasai operation.

To investigate the association between chronic cholestatic jaundice, systemic immunity, and various infectious complications in patients with biliary atresia (BA), we performed a survey of the systemic immune function in 30 children with BA. Patients were divided into a jaundice group (total serum bilirubin > or = 2 mg/dL for >6 mo) and control group (total serum bilirubin <2 mg/dL for >6 mo) with comparable age. Patients were tested for serum immunoglobulin and complement levels, mitogen response, interleukin (IL)-4, IL-5, and interferon-gamma production after phytohemagglutinin (PHA) stimulation, blood cell and lymphocyte subpopulation counts, phagocytic function, and leukocyte adhesion complex. They were then followed prospectively for 6 mo, and severe infectious complications requiring hospitalization were recorded. Compared with jaundice-free patients, T-lymphocyte proliferation function, determined by PHA mitogen test was significantly lower (p = 0.02) in BA patients with chronic cholestatic jaundice after a Kasai operation. During the study period, patients with chronic cholestatic jaundice had a higher risk of severe infectious complications than their jaundice-free counterparts (risk ratio = 5.87; p = 0.001). In conclusion, BA patients with chronic cholestatic jaundice are associated with impairment of T-lymphocyte proliferation and increased incidence of severe infectious complications.

Adolescent↗
PubMed2006

Time course of acylcarnitine elevation in neonatal intrahepatic cholestasis caused by citrin deficiency.

Citrin is a mitochondrial membrane aspartate-glutamate carrier, and citrin deficiency causes both hyperammonaemia in adults (adult-onset type II citrullinaemia, CTLN2) and neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD), with metabolic derangements in gluconeogenesis, aerobic glycolysis, urea synthesis, UDP-galactose epimerase activity, and possibly fatty acid synthesis and utilization. Through neonatal screening and case review, four patients with NICCD who had an acylcarnitine profile during infancy were all found to have an elevation of free carnitine, C2-carnitine, and long-chain acylcarnitines. These metabolic abnormalities appeared after the rise of citrulline and bilirubin, but before the elevation of alanine aminotransferase and aspartate aminotransferase. Although the rise of free carnitine and acylcarnitines seems to be a benign condition, the sequential changes of these metabolic derangements may give clues to the pathogenesis of this interesting disorder.

Alanine↗
PubMed2006

Hepatitis B virus mutation in children.

Due to the lack of proof reading activity of hepatitis B virus (HBV) polymerase, mutation/variation of the viral sequence is frequently found during long term follow-ups. In the majority of children with chronic HBV infection, wild type HBV is the dominant viral strain during the natural course of chronic HBV infection. During long-term follow-up, HBV precore mutants developed spontaneously in approximately 10 to 24% of children before HBeAg seroconversion and in around 50% of children after HBeAg seroconversion mutants. Occasionally, children may be infected primarily by mutant strains of HBV. Approximately 36% of children with fulminant hepatitis and 30% of children with acute hepatitis B were infected by precore mutants of HBV transmitted by their mothers or blood donors. In addition, after universal HBV vaccination, HBV surface gene variants emerge or are selected under the immune pressure generated by the host or by administration of hepatitis B immune globulin and hepatitis B vaccination. In HBV DNA positive children from four sequential surveys in Taiwan, the prevalence of hepatitis B surface gene a determinant mutants increased from 7.8% before the vaccination program, to 19.6%, 28.1% and 23.1% at 5, 10 and 15 years after the program. Nucleoside analogue may also induce mutant strains, which reduces the antiviral effects. The most common example is the YMDD mutation of the HBV polymerase gene after antiviral therapy with lamivudine. It developed in 19% of the treated children. In conclusion, children may be infected primarily by mutant strains of HBV either naturally during acute HBV infection. Those infected with wild type HBV initially may develop mutant strains gradually during the course of chronic infection under the host immune pressure. Vaccine escape mutants may develop after immunoprophylaxis. In addition, antiviral therapy with nucleoside analogues may also induce drug resistant mutant strains. Understanding the viral mutation status will help to design accurate strategies of immmunoprophylaxis and antiviral therapy against HBV infection.

Antiviral Agents↗
PubMed2006

Hepatic steatosis and neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) in Taiwanese infants.

OBJECTIVES: To explore the prevalence of hepatic steatosis and neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) in Taiwanese infants with idiopathic intrahepatic cholestasis. STUDY DESIGN: The liver specimens from 69 infants with idiopathic intrahepatic cholestasis were reviewed (1993-2004); 11 of them (14.7%) had hepatic steatosis. Six patients with hepatic steatosis participated in the genetic study for the SLC25A13 gene under parental consent. RESULTS: Infants with cholestasis and hepatic steatosis had lower aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels than those with cholestasis alone. Three of the six infants in the genetic study had homozygous 851del4 mutation; for the others, homozygous 1638ins23 mutation, compound heterozygous 851del4/IVS6+5G-->A mutation, and heterozygous IVS6+5G-->A mutation were found for each one. Eleven of the total 12 alleles (91.7%) were demonstrated to have SLC25A13 gene mutations. CONCLUSIONS: Metabolic and genetic studies for NICCD should be performed in Asian infants with idiopathic intrahepatic cholestasis and hepatic steatosis. The 851del4 mutation on the SLC25A13 gene accounts for the major genotype expression of patients with NICCD in Taiwan.

Asian People↗
PubMed2006

HLA typing associated with hepatitis B E antigen seroconversion in children with chronic hepatitis B virus infection: a long-term prospective sibling cohort study in Taiwan.

OBJECTIVE: To conduct a prospective cohort study to clarify the relationship between human leukocyte antigen (HLA) polymorphisms and the seroconversion of hepatitis B e antigen (HBeAg). STUDY DESIGN: In the prospective cohort study, 81 HBeAg-positive children with chronic hepatitis B virus (HBV) infection from 40 unrelated families were recruited and followed-up regularly for a mean period of 17.70 +/- 3.23 years. The association between HLA antigen and the age at HBeAg seroconversion was analyzed using Cox regression model with shared frailties under left truncation and right censorship. RESULTS: HLA-B61 and HLA-DQB1*0503 antigens predicted a higher HBeAg seroconversion rate (relative incidence = 6.17 and 3.22, P = .024 and .017, respectively). Within-family frailty in our sibling cohort study demonstrated a negligible or a low degree of within-family correlation with spontaneous HBeAg seroconversion in each HLA antigen. CONCLUSIONS: HLA class I antigen B61 and class II antigen DQB1*0503 are associated with earlier HBeAg seroconversion in Taiwanese children with chronic HBV infection.

Adolescent↗
PubMed2006

Clinical improvement following home parenteral nutrition in pediatric patients with intestinal failure.

BACKGROUND/PURPOSE: Home parenteral nutrition (HPN) is being increasingly used to treat children with intestinal failure. This study evaluated the long-term growth, outcome and complications in Taiwanese pediatric patients with intestinal failure who were treated with HPN. METHODS: This retrospective study included 27 consecutive pediatric patients with intestinal failure who received long-term HPN between 1987 and 2002. These patients were categorized into two groups according to whether they had short bowel syndrome or a bowel motility disorder. Growth, prognosis and complications, including cholestasis, hypoglycemia, hyperglycemia and infections were compared between the two groups. RESULTS: The median age of starting HPN was significantly younger in patients with short bowel syndrome (5 months) than in patients with motility disorders (1.9 years). The median duration of HPN treatment in the overall group was 13.5 months (range, 2.1-113.1 months); weight and height increased 1.7 +/- 2.3 and 1.0 +/- 1.6 in z score, respectively. The most common complications were cholestatic liver disease (52%), hypoglycemia (15%) and hyperglycemia (33%). All patients maintained stable serum glucose levels at follow-up. Cholestatic liver disease developed after 2.3 +/- 2.0 months of total HPN in 13 patients, which subsided after 9.7 +/- 6.9 months in 11 patients, while two patients died. The mean incidence of central venous infection was 3.0 +/- 3.3 per 1000 HPN days. The most common pathogens were Staphylococcus spp. (50%) and Candida spp. (30.6%). CONCLUSION: HPN treatment can successfully provide a bridge to enteral nutrition in pediatric patients with intestinal failure. The metabolic disturbances and cholestasis are usually transient, but infection control is important throughout the period of HPN treatment.

Adolescent↗
PubMed2006

Microbial etiology of acute gastroenteritis in hospitalized children in Taiwan.

BACKGROUND/PURPOSE: Viral infections are the most common causes of acute infectious diarrhea in the pediatric population. To explore any possible microbial etiologies of acute gastroenteritis in children, we detected stool viral antigen including rotavirus, adenovirus, norovirus and astrovirus. We also studied the possible precipitating factors. METHODS: During a period of 1 year (from October 2003 to September 2004), children from birth to 15 years old admitted to the pediatric ward were prospectively surveyed. Stool specimens were collected within 48 hours after admission and then frozen at -40 degrees C until analysis. Enzyme immunoassay was used to detect rotavirus, astrovirus, norovirus and adenovirus. Bacterial culture was performed at the same time. RESULTS: During the study period, 82 stool samples were collected due to acute gastroenteritis and fit the definition of a diarrhea episode. Forty-two (51.2%) patients with viral infection, 11 (13.4%) with bacterial infection, and six (7.3%) with mixed viral and bacterial infection were detected. The most prevalent virus was rotavirus (35.4%), followed by norovirus (29.3%). The most prevalent cause of bacterial infection was Salmonella (19.5%). With regard to clinical severity, rotavirus resulted in longer hospital stay, higher rate of vomiting, stool occult blood, leukocytosis, lower rate in stool pus cell, and C-reactive protein elevation more than 5 mg/dL as compared with norovirus. Only the difference in hospital stay reached significant statistical difference. CONCLUSION: Norovirus is an important cause of acute gastroenteritis in children, although rotavirus is still the leading cause of pediatric acute gastroenteritis.

Acute Disease↗
PubMed2006

Impact of hepatitis B vaccination on hepatitis B disease and nucleic acid testing in high-prevalence populations.

Hepatitis B virus (HBV) infection is highly prevalent in Asia, Africa, southern Europe and Latin America, HBV vaccination has effectively reduced the acute and chronic infection rates as well as related complications in the vaccinated children. The incidence of hepatocellular carcinoma in children has been reduced to approximately 25% of the incidence before the vaccination program, and fulminant hepatitis in children has also been reduced after universal hepatitis B vaccination. HBV DNA sero-positive rate was 98-100% in HBsAg positive vaccinated children, while the positive rate was only 11-20% in those vaccinees with a negative HBsAg but positive anti-HBc reaction. Hepatitis B surface gene mutants in HBV DNA positive children increased gradually from 7.8% before the vaccination program, to 19.6%, 28.1% and 23.1% at 5, 10 and 15 years after the vaccination program. Long-term follow-up of vaccinated children has confirmed that universal HBV vaccination in infancy has produced adequate protection up to 14 years of age. The annual decay rate of hepatitis B surface antibody (anti-HBs) was 10.2% in children who did not receive a booster dose. The new HBV infection rate was not different between those who did and those who did not receive a booster dose of HBV vaccine. During a follow-up period of seven years for 1200 vaccinated 7-year-old children in Taiwan, the mean annual hepatitis B core antibody sero-conversion rate was 0.2%. All were negative for HBV DNA. No new chronic HBV infections developed. A booster dose of HBV vaccine is not recommended in children under 15 years of age. Systematic HBV DNA screening of a large population such as blood donors may be instrumental in following the long-term effect of the universal vaccination program on the incidence of silent HBV infection and vaccine escape mutants.

Hepatitis B↗
PubMed2006

SEN virus infection in children in Taiwan: transmission route and role in blood transfusion and liver diseases.

BACKGROUND: SEN virus (SENV) is a newly discovered DNA virus. We conducted this study to evaluate potential modes of SENV transmission and the pathogenic effect of SENV on liver diseases in children. METHODS: Polymerase chain reaction was used to detect 2 SENV variant (SENV-D and SENV-H) DNA in sera from healthy individuals and diseased children. Nucleotide sequence of SENV was determined by direct sequencing. RESULTS: SENV infection was assessed in healthy individuals, including 50 newborns (sera collected from the umbilical cord), 24 infants, 46 preschool children (aged 1-6 years), 42 school children of an age before that of the first sexual experience (aged 7-12 years), 62 adolescents (13-18 years), 72 young adults (19-30 years) and 32 adults (>30 years). The prevalence of SENV-D and/or SENV-H (SENV-D/H) viremia in each group was 0%, 17%, 24%, 24%, 27%, 33% and 40%, respectively. The prevalence of SENV-D/H viremia in 18 children with non-A to E hepatitis, 64 thalassemic children, 80 children transfused during cardiac surgery, 30 children with chronic hepatitis B, 9 children with chronic hepatitis C and 32 infants with biliary atresia was 11%, 61%, 80%, 83%, 67% and 50%, respectively. SENV was found more frequently in all patient groups than in 174 age-matched controls (P < 0.01), with the exception of non-A to E hepatitis (11% versus 24% in the control group; P = 0.27). In 2 infants with proven intrauterine hepatitis B viral infection, identical SENV-D nucleotide sequence existed in both the maternal and neonate serum. Elevated alanine aminotransferase concentrations were rarely observed in children who acquired isolated SENV viremia because of transfusion for surgery. Infection with SENV in children with chronic hepatitis C virus or hepatitis B viral infection was not associated with higher peak alanine aminotransferase values. CONCLUSION: SENV is transmitted mainly via nonparenteral daily contact and frequently occurs early in life. Transfusion can significantly increase the rate of SENV viremia. SENV does not appear to cause hepatitis in children.

Adolescent↗
PubMed2006

Long-term prognosis of patients with biliary atresia: a 25 year summary.

OBJECTIVE: The purpose of this study was to delineate the long-term prognosis of biliary atresia (BA) in Taiwan. STUDY DESIGN: From 1976 to 2000, 185 children were diagnosed with BA, 22 underwent exploratory laparotomy without Kasai operation, and 163 underwent Kasai operation, of which 141 cases had long-term follow-up and formed the basis of this study. The outcome was analyzed. RESULTS: Among the 141 BA children studied who underwent Kasai operation, 115 (81.6%) had recoloration of stools, and 86 (61.0%) became jaundice-free (bilirubin <34 micromol/L) [corrected]. The resolution of jaundice and the absence of repeated cholangitis contributed to better outcome. Five and 10 year survival rates with native liver were 35% and 31%, respectively. Liver transplantation was performed in 19 patients (all but 2 with a living-related donor), and 15 (79%) survived. Five and 10 year overall survival rates for BA patients were 41.9% and 40.2%, respectively. CONCLUSIONS: The study delineated the long-term outcome of BA in an Asian country other than Japan. Survival with native liver after a Kasai operation in Taiwan was similar to that in the American and European series. Limited donors for liver transplantation in the years of the study accounted for the poor overall prognosis of BA patients in this series.

Adolescent↗
PubMed2006

Post-transplantation lymphoproliferative disorders localizing to the gastrointestinal tract after liver transplantation: report of five pediatric cases.

Post-transplantation lymphoproliferative disorder (PTLD) is a life-threatening complication of organ transplantation. PTLD can occur in every kind of organ transplantation. From July 1992 to July 2004, five patients were diagnosed at our transplantation center with PTLD after pediatric liver transplantation. During this period, there were 52 pediatric patients (<18 yr) receiving an orthotopic liver transplantation (OLT) at our center. All five patients had transmural gastrointestinal (GI) PTLD, which occurred mostly in the stomach and duodenum. Epstein-Barr virus (EBV) in situ was demonstrated in each case. EBV viral load was noted to be an important risk factor. Treatment included dose reduction of immunosuppressants and anti-CD20 antibody infusion. Chemotherapy, including cyclophosphamide, doxorubicin, vincristine, and prednisolone, was given to three patients. Four patients have survived more than 10 months until now after treatment. The one who was unresponsive to chemotherapy and anti-CD20 antibody had diffuse metastasis and died of systemic candidiasis. In our series, each PTLD involved the GI tract. The mechanism of this phenomenon is unclear, but these five cases indicate the high incidence of PTLD in pediatric solid organ transplantation.

Antigens, CD20↗
PubMed2006

Neonatal Dubin-Johnson syndrome: long-term follow-up and MRP2 mutations study.

Neonatal Dubin-Johnson syndrome (DJS) is rarely diagnosed and mutational analysis of multidrug-resistance-associated protein 2 (MRP2) in such patients had not been reported. We aimed to investigate the possible correlations between genotype and phenotype of patients with DJS. Four cases of DJS, two diagnosed during the neonatal period and two diagnosed at adolescence, were followed for 5-20 y. Mutational analysis in the MRP2/ABCC2 gene was performed in all four cases. Biphasic pattern of jaundice attack was observed in one patient who was followed for 20 y, with jaundice subsiding before 1 y of age and recurring at adolescence. Six novel mutations in four patients were found, including deletions (2748del136, 3615del229, and Del3399-3400), and missense mutations (L441M and E1352Q) and nonsense mutation (Y1275X). The immunohistochemical staining in liver tissues from two patients with neonatal onset showed negative staining for MRP2. Reviewing previously reported cases, all patients diagnosed as DJS before 10 y of age have mutations involving one of the two ATP-binding cassettes (ABC) of the MRP2. This study suggests that long-term follow-up is indicated for neonatal DJS because of possible recurrence and/or second attacks of jaundice in later life, and that disruption of functionally important ABC domains in MRP2 may be related to the earlier onset of the disease.

Adolescent↗
PubMed2006

Screening for biliary atresia by infant stool color card in Taiwan.

OBJECTIVE: We aimed to detect biliary atresia (BA) in early infancy to prevent additional liver damage because of the delay of referral and surgical treatment and to investigate the incidence rate of BA in Taiwan. METHODS: A pilot study to screen the stool color in infants for the early diagnosis of BA was undertaken from March 2002 to December 2003. We had designed an "infant stool color card" with 7 numbers of different color pictures and attached it to the child health booklet. Parents were then asked to observe their infant's stool color by using this card. The medical staff would check the number that the parents chose according to their infant's stool color at 1 month of age during the health checkup and then send the card back to the stool color card registry center. RESULTS: The average return rate was approximately 65.2% (78,184 infants). A total of 29 infants were diagnosed as having BA, and 26 were screened out by stool color card before 60 days of age. The sensitivity, specificity, and positive predictive value were 89.7%, 99.9%, and 28.6%, respectively. Seventeen (58.6%) infants with BA received a Kasai operation within 60-day age period. The estimated incidence of BA in screened newborns was 3.7 of 10,000. CONCLUSIONS: The stool color card was a simple, efficient, and applicable mass screening method for early diagnosis and management of BA. The program can also help in estimating the incidence and creating a registry of these patients.

Biliary Atresia↗
PubMed2005

Prevention of hepatocellular carcinoma by universal vaccination against hepatitis B virus: the effect and problems.

PURPOSE: In spite of the success of hepatitis B immunization, still a significant proportion of childhood hepatocellular carcinoma (HCC) failed to be prevented by the hepatitis B immunization program. This study is aimed to investigate the problems in the HCC prevention in children. EXPERIMENTAL DESIGN: All HCC children ages 6 to 14 diagnosed between 1981 and 2000 in Taiwan were collected from two national childhood HCC registry systems. We analyzed the causes of HCC prevention failure and the risk ratio of HCC among hepatitis B carriers born before versus after the vaccination program. RESULTS: The incidence of HCC per 100,000 children declined from 0.54 to 0.20 in those born before versus after the vaccination program (risk ratio, 0.36). Vaccine failure (33.3-51.4%) and failure to receive hepatitis B immunoglobulin at birth (42.4-57.5%) were the main causes of HCC prevention failure. Mother-to-child transmission of hepatitis B virus infection is an important risk factor of HCC development. This is evidenced by the very high hepatitis B surface antigen seropositive rate in our HCC children (97%) and their mothers (96%). Hepatitis B carrier children born after the vaccination program had a higher risk of developing HCC than those born before the program (risk ratio, 2.3-4.5). CONCLUSIONS: Vaccine failure and failure to receive hepatitis B immunoglobulin are the main problems preventing eradication of HCC. Hepatitis B carrier children born after the immunization program have a higher risk of developing HCC than those born before.

Adolescent↗
PubMed2005

Fecal elastase 1, serum amylase and lipase levels in children with cholestasis.

BACKGROUND/AIM: The pancreatic functions of children with cholestatic liver diseases were unclear. Due to anatomic vicinity and common ontogenic origin, hepatobiliary disorders of infancy may also affect pancreatic function. The aim of the study was to evaluate the exocrine pancreatic function and common pancreatic function tests in children with cholestatic disorders. METHODS: In 40 children with cholestasis, fecal elastase 1 (FE1) concentrations were measured. Serum amylase and lipase values were tested. The diagnoses included 32 patients with extrahepatic cholestasis (biliary atresia (BA) and choledochal cyst), and 8 patients with intrahepatic cholestasis (progressive familial intrahepatic cholestasis and Alagille syndrome). None had renal insufficiency or clinical symptoms/signs of acute pancreatitis. RESULTS: All the patients had normal FE1 (>200 microg/g). Nineteen percent (7/37) had elevated serum amylase levels (>100 U/l). Thirty-two percent (12/37) had elevated serum lipase levels above the normal (>120 U/l). Seventy-three percent (8/11) of BA patients with bilirubin >2 mg/dl had elevated serum lipase levels compared to 18% (3/17) with bilirubin < or = 2 mg/dl (p = 0.0036). None had detectable pancreatic abnormality on ultrasonography and magnetic resonance images. CONCLUSIONS: None of the cholestatic children in this study had exocrine pancreatic insufficiency as detected by FE1. Hyperamylasemia and/or hyperlipasemia were frequently found. In children with BA, those with impaired biliary excretion tended to have elevated serum pancreatic enzymes as compared with those who had no jaundice. A decreased hepatic metabolism may be the cause.

Alagille Syndrome↗
PubMed2005

Developmental expression of canalicular transporter genes in human liver.

BACKGROUND/AIMS: BSEP, MRP2, and MDR3 are major hepatic canalicular transporters mediating bile secretion. Their expression in human liver during development has not been reported. METHODS: Human liver samples from fetus at gestational age 14-20 weeks, adult livers and liver samples of infants with biliary atresia were tested for mRNA expression of BSEP, MDR3, MRP2, NTCP, FIC1, and FXR genes by using real-time RT-PCR. Immunohistochemical staining of BSEP, MDR3, and MRP2 were performed on fetal and adult livers. RESULTS: All the genes tested were expressed at mid-gestational age. MDR3 and NTCP showed significant lower levels in fetal livers compared to adults. In patients with biliary atresia, all the genes tested showed higher mean expression levels than adults except for NTCP, but not statistically significant. The immunohistochemical staining of MRP2 in fetal liver was canalicular, BSEP showed both intracellular and canalicular staining, and MDR3 staining was faint, only occasional canalicular pattern could be seen. CONCLUSIONS: The major canalicular transporter genes are expressed at mid-gestational stage during human fetal development, but are different in expression level and targeting pattern, indicating differential regulation and maturation.

ATP Binding Cassette Transporter, Subfamily B↗