PubMed Health⌕ Search

Biomedical subjects

Jeong Kee Seo

Publications and source records attributed to Jeong Kee Seo.

15 recordsLinked to original sources

Long-term protection against hepatitis B in pediatric liver recipients can be achieved effectively with vaccination after transplantation.

Liver recipients who have antibodies to hepatitis B core antigen (anti-HBc) or received an anti-HBc positive liver graft are at risk of acquiring de novo hepatitis B infection so a life long prophylaxis is required. A post-transplant vaccination against hepatitis B virus (HBV) can offer a better alternative than either hepatitis B hyperimmune globulin (HBIG) or lamivudine. This study investigated the course of anti-HBs titer after vaccination and analyzed the factors that influence the response. Between October 1999 and February 2003, 37 pediatric patients were given a post-transplant vaccination when an anti-HBc positive graft was used, the recipient was anti-HBc positive, or when anti-HBs titer was below 20 IU/L irrespective of the serological status. Thirty-three patients responded to the vaccine and did not require further HBIG injections at a mean follow up of 33.6 months. Fifteen patients were good responder and only needed a single set of vaccines, and 18 were poor responder needing additional boosters. Two patients developed de novo hepatitis B infection and two required additional HBIG injections. Preoperative severity of liver disease, serological status of HBV of recipient or donor, use of HBIG or pulse steroid therapy, type of vaccines, and dose or time interval between doses had no influence on response rate. Recipients with a high preoperative anti-HB titer, small graft-recipient weight ratio (GRWR), greater catch up growth, heavier body weight, lower tacrolimus level at the time of vaccination, and longer time interval between transplant or steroid medication and vaccination yielded good response. If well tailored, post-transplant vaccination can be effective and offer patients prophylaxis against de novo hepatitis B infection for a prolonged period of time.

Cadaver↗

[Wilson disease: an update].

Wilson disease (WD) is an autosomal recessive disorder of copper transport that results in accumulation of copper primarily in the liver, the brain and the cornea. WD is the most common inherited liver disease with the prevalence of 1: 37,000 in the pediatric population in Korea. Mutations in the ATP7B gene cause failure of copper excretion into the bile and a defective incorporation of copper into ceruloplasmin. More than 300 mutations in the ATP7B gene have been described so far. Mutations differ between ethnic groups. The p.R778L (an allele frequency of 37%), p.A874V (13%), p.L1083F (8%) and p.N1270S (6%) are the common major mutations in Korea. Conflicting results on genotype/phenotype correlations of the most common mutations have been reported in various countries. There seems to be no correlation between the R778L mutation and age of onset or clinical manifestations in Korean patients. None of the laboratory parameters alone allows a definite diagnosis of WD. In a nation-wide survey of WD, low serum ceruloplasmin (<20 mg/dL), high 24 hour urine copper (>100 microgram), high hepatic copper content (>250 microgram/g of dry liver) and Kayser-Fleischer rings were found in 96%, 86%, 88%, and 73% of the 550 Korean patients respectively. A combination of any two of the above 4 laboratory findings is strong support for a diagnosis of WD. For the last couple of years, genetic testing has been playing an increasingly important role in diagnosing WD. Direct DNA sequencing did confirm WD in 98% of the Korean patients. Two mutations were detected in 70% and one mutation in 28% of the patients who showed characteristic biochemical and clinical findings of WD. Genetic testing, either by haplotype analysis or by mutation analysis, is the only reliable tool for differentiating heterozygote carriers from affected asymptomatic patients. The agents of the first choice among chelators and zinc in specific clinical situations of WD is still a matter of debate. Because of frequent side effects and initial neurologic deterioration of penicillamine therapy, less toxic trientine or zinc has gradually replaced penicillamine over the past few years. Trientine or tetrathiomolybdate has been increasingly recommended as the first-line treatment for neurologic WD. Currently, liver transplantation is not recommended as primary treatment for neurologic WD. Recently published data show that initial zinc therapy for asymptomatic/presymptomatic patients and maintenance zinc therapy in patients after long term chelation are safe and effective. Further researches and the new guidelines on the proper management of patients with WD are needed.

Adenosine Triphosphatases↗

Hepatocellular carcinoma occurring in alagille syndrome.

Hepatocellular carcinoma only rarely occurs in Alagille syndrome. Here, we report on three cases of hepatocellular carcinoma associated with Alagille syndrome. All three patients were boys and presented with jaundice. In addition, they had the characteristic facial appearance of Alagille syndrome with cardiac, vertebral, and eye anomalies, and all had passed acholic stools from the neonatal period. Liver biopsies were diagnosed as bile duct paucity, compatible with Alagille syndrome in two cases, but the third case showed marked bile duct proliferation at the initial liver biopsy when 7 months old, which made diagnosis difficult. Eventually, all three cases progressed to biliary cirrhosis and hepatocellular carcinoma, which occurred at 17 months, 4 years, and 7 years, respectively. Because of the unusual liver histology and early onset of hepatocellular carcinoma, careful clinicopathologic correlations and close monitoring are required for the diagnosis of Alagille syndrome and for the early detection of hepatocellular carcinoma.

Alagille Syndrome↗

Molecular epidemiology of adenovirus infection among pediatric population with diarrhea in Asia.

A total of 3,577 fecal specimens from infants and children with acute gastroenteritis in Japan, Korea and Vietnam during 1998 and 2001 were tested for adenovirus by the ELISA method. Of these, adenovirus was detected in 158 (4.4%). The detection rate of adenovirus was highest in Korea (8.7%, 20/231) followed by 5.0% (100/1,991) in Japan and 2.8% (38/1,355) in Vietnam. All adenoviruses were further serotyped by PCR-RFLP. The diversity of adenovirus serotypes including Ad2, 3, 5, 8, 31, 40 and 41 was demonstrated. Worth of note was a decrease in the rate of isolation of Ad40 (7.6%, 12/158) and a concomitant increase of Ad41 (63.9%, 101/158) to become the predominant serotype. Another interesting feature of the study was the presence of Ad3 (4.0% and 30%) and Ad8 (8.0% and 20%) in Japan and Korea, respectively, which is mainly associated with keratoconjunctivitis worldwide. Our result underscored the importance of adenovirus in association with acute gastroenteritis in Asian countries.

Adenoviridae↗

Diagnostic accuracy of the C-urea breath test in children: adjustment of the cut-off value according to age.

BACKGROUND AND AIMS: The (13)C-urea breath test ((13)C-UBT) is a reliable non-invasive method of diagnosing Helicobacter pylori infection in adults and children. However, only a few validation studies have been performed on the (13)C-UBT in very young children. The purpose of the present study was to evaluate the diagnostic accuracy of the (13)C-UBT according to age, and to determine the optimal cut-off value in children. METHODS: A total of 307 (13)C-UBT were performed in 274 children. All were compared with the results of endoscopic biopsy-based methods to confirm H. pylori infection. Seventy-five milligrams of (13)C-urea was ingested without a test meal. Two breath samples were collected at 0 and 30 min. The optimal cut-off value of the (13)C-UBT was assessed by determining the sensitivity, specificity, false negative, and false positive results, at cut-off values ranging from 2.0 to 10.0 per thousand. RESULTS: The delta over baseline (DOB) values of the (13)C-UBT showed a significant negative correlation with age in both the H. pylori-positive group (r = -0.309; P = 0.005) and the H. pylori-negative group (r = -0.162; P = 0.015). High false positive results and low specificity were noted in children aged 6 years or less compared with children older than 6 years at a cut-off value of 4.0 per thousand (false positives; 8.3%vs 0.85%, specificity; 89.8%vs 98.8%). After adjusting the cut-off value, the optimal cut-off values were found to be 4.0 per thousand in children older than 6 years and 7.0 per thousand in children aged 6 years or less. CONCLUSIONS: The cut-off value of the (13)C-UBT recommended regardless of age must be adjusted in preschool children to reduce the false positive results.

Adolescent↗

Immunohistochemical studies of pediatric intestinal pseudo-obstruction: bcl2, a valuable biomarker to detect immature enteric ganglion cells.

To identify the diagnostic pitfalls as well as the value of immunohistochemical studies in making a pathologic evaluation of a pediatric intestinal pseudo-obstruction (IPO), this study reassessed the pathology of 87 surgically resected intestines from 80 patients under the impression of IPO and 10 normal controls using immunohistochemical studies. The main diagnostic pitfall was the interpretation of the enteric nervous plexuses in the transitional zone and the detection of the indistinct or immature neurons indistinguishable from enteric glial cells or satellite cells. Immunohistochemical study was a very helpful diagnostic adjunct to delineating the immature neurons (bcl2), the size of the enteric ganglia and neuromuscular innervation (S-100 protein, synaptophysin, and CD56), and the interstitial cell of Cajal (c-Kit) and myopathy (SMA). With help of immunohistochemistry, our series of IPO could classify as neuropathy (92.5%), myopathy (2.5%), and the idiopathic forms (3.8%) more clearly. In terms of the types of neuropathy, Hirschsprung's disease (HD), pure hypoganglionosis, and intestinal neuronal dysplasia (IND-B) were diagnosed in 71.3%, 6.3%, and 48.8% of patients, respectively. IND-B was associated with other neuropathies, HD in 77.0% and hypoganglionosis in 7.7%, rather than being present in a pure form. Immature ganglion cells were found in 48.8%. Because a reduced number of interstitial cells of Cajal was commonly associated with HD in 84.2%, hypoganglionosis in 40%, and IND-B in 76.9% of cases, it might be a preceding or aggravating factor related to an IPO. In terms of detecting immature ganglion cells, we found bcl2 most helpful.

Biomarkers↗

Histopathology and expression of Ki-67 and cyclooxygenase-2 in childhood Helicobacter pylori gastritis.

BACKGROUND: Helicobacter pylori infection has been implicated in many pathobiologic changes that are linked with the pathogenesis of gastric cancer. The majority of studies have been performed in adults; however, H. pylori infection in children may be of greater significance because, in general, it reflects the early phase of infection. We therefore investigated several pathobiologic changes in the gastric mucosa of H. pylori-infected children, including histopathologic features, cell proliferation-associated Ki-67 antigen expression, and cyclooxygenase (COX)-2 expression. METHODS: Sixty-five children with nonulcer dyspepsia were included; 52 were infected with H. pylori, while the other 13 were free of H. pylori infection. A histopathologic review of biopsy specimens obtained from the gastric antrum was performed according to the updated Sydney system. Immunohistochemical expressions of Ki-67 and COX-2 were scored quantitatively or semiquantitatively. RESULTS: The H. pylori-infected group was significantly associated with a higher grade of chronic inflammation, acute inflammation, and glandular atrophy. Ki-67 and COX-2 expressions were found to be significantly higher in the H. pylori-infected group. COX-2 expression was correlated with acute and chronic inflammation and Ki-67 expression. COX-2 expression was observed mainly in the monocytic cells and myofibroblasts in the lamina propria. CONCLUSIONS: H. pylori-infected children, suggestive of the early phase of infection, exhibit increased gastric epithelial cell proliferation, increased COX-2 expression, and other pathobiologic features that may contribute to gastric carcinogenesis. These results have clinical significance for the early introduction of eradication of H. pylori infection in childhood.

Adolescent↗

Characterizations of adenovirus type 41 isolates from children with acute gastroenteritis in Japan, Vietnam, and Korea.

Genetic and antigenic characterizations of 70 strains of adenovirus type 41 (Ad41), isolated between 1998 and 2001 from children in Japan, Vietnam, and Korea, were done by DNA restriction enzyme (RE) analysis, sequencing analysis, and monoclonal antibody (MAb)-based enzyme-linked immunosorbent assay (ELISA). Eight genome types were observed in the present study, among which D25, D26, D27, and D28 were novel genome types. These eight genome types were divided into two genome-type clusters (GTCs) based on phylogenetic analysis of the hypervariable regions (HVRs) of the hexon. GTC1 includes D1, D25, D26, D27, and D28, and the GTC2 contains D4, D12, and D22. The amino acid homologies among the members within a GTC were 97 to 100%, whereas between the members of different GTCs the homologies were 92 to 94%. The specificity of the GTC classification was confirmed by ELISA with MAb 1F, which was selected by the Ad41 prototype Tak strain. It was found that only the isolates of GTC1 but not of GTC2 reacted with MAb 1F. These results suggest that Ad41 isolates from the three countries should be classified into two subtypes. The accumulation of amino acid mutations located in HVRs of hexon are indicative for the classification of Ad41 subtype.

Acute Disease↗

Active immunization against de novo hepatitis B virus infection in pediatric patients after liver transplantation.

The shortage of donor organs occasionally mandates the use of hepatic allografts from anti-HBc (+) donors. HBIG and/or lamivudine are recommended for the prevention of de novo HBV infection in naive patients, but there are attendant problems, such as mutant strain emergence and high cost. Active immunization presents a better alternative than the use of HBIG or lamivudine, if it can be proven to be effective. Accordingly, we investigated the outcome of HBV vaccination in pediatric hepatic transplant recipients. Between July 1999 and October 2001, 19 pediatric recipients were administered HBV vaccinations after liver transplantation at Seoul National University Hospital. Nine patients received a graft from anti-HBc (+) donors and 10 from anti-HBc (-) donors. When steroid was withdrawn, recombinant HBV vaccine was administered. The median follow-up period after vaccination was 10.0 +/- 5.2 months. Seventeen of the 19 patients showed a positive response to vaccination. In 9 patients who received grafts from anti-HBc (+) donors, 2 patients showed no response, 4 patients low response (peak HBsAb titer <1,000 IU/L), and 3 patients high response (peak HBsAb titer >/=1,000 IU/L). De novo HBV infection developed in 1 of 2 patients who showed no response to vaccination. In 10 patients who received grafts from anti-HBc (-) donors, 5 showed a low response and 5 a high response. In conclusion, HBV vaccination in pediatric patients after liver transplantation appeared to exhibit some effectiveness at protecting young children that received a graft from anti-HBc (+) donors from de novo HBV infection.

Child, Preschool↗

Hypertrophic obstructive cardiomyopathy with infundibular stenosis treated by alcohol ablation therapy.

This report describes an uncommon case of hypertrophic obstructive cardiomyopathy (HOCM) accompanying infundibular stenosis of the right ventricle treated by alcohol ablation therapy, in a 28-yr-old male patient presenting with dyspnea on exertion. HOCM with infundibular stenosis was detected by echocardiogram and cardiac catheterization and patient has dynamic obstructions of both ventricular outflow tracts. We performed alcohol ablation therapy to improve clinical symptoms and to relieve dynamic obstructions of both ventricular outflow tracts. This is the first case in which HOCM with infundibular stenosis of the right ventricle was treated by alcohol ablation therapy.

Adult↗

[Diagnostic role of anti-Saccharomyces cerevisiae and antineutrophil cytoplasmic autoantibodies in pediatric inflammatory bowel disease].

BACKGROUND/AIMS: Combined measurement of perinuclear antineutrophil cytoplasmic autoantibodies (pANCA) and anti-Saccharomyces cereviseae mannan antibodies (ASCA) has recently been suggested as a valuable diagnostic approach to inflammatory bowel disease (IBD) in the pediatric age group. The aim of this study was to test the accuracy of the assay using pANCA and ASCA in diagnosing pediatric ulcerative colitis (UC) and Crohn's disease (CD). METHODS: Sera were collected from 25 patients with IBD (17 with CD, 8 with UC) and 32 healthy controls. The levels of pANCA and ASCA were determined by using a standard indirect immunofluorescence technique on ethanol-fixed granulocytes and an ELISA assay, respectively. RESULTS: In patients with UC, the sensitivity, specificity, and positive predictive value of the pANCA test were 38%, 88%, and 60%, respectively. Such values were not changed significantly in the case of positive pANCA and negative ASCA. The sensitivity, specificity, and positive predictive value of ASCA test in diagnosing CD were 71%, 88%, and 92%, respectively. The combination of pANCA negative and ASCA positive was not significant. CONCLUSIONS: ASCA and pANCA assays are highly disease specific for CD and UC, respectively. These serological tests can assist clinicians in diagnosing and categorizing patients with IBD and may be useful in making therapeutic decisions.

Adolescent↗

Serum ferritin and Helicobacter pylori infection in children: a sero-epidemiologic study in Korea.

BACKGROUND: Helicobacter pylori infection is known to affect iron metabolism and serum ferritin levels, which are reduced in adults with H. pylori infection. The aim of the present study was to investigate the association between H. pylori infection and iron status in healthy Korean children. METHODS: The H. pylori seropositivity in 753 schoolchildren aged 6-12 years was screened for using an ELISA and confirmed by western blot analyses. Serum ferritin levels were measured using an immunoradiometric assay in 36 H. pylori-seropositive children and in 72 age- and gender-matched seronegative controls. RESULTS: The median serum ferritin levels were significantly lower in H. pylori-seropositive children than in seronegative controls (24 vs 39 ng/mL; P < 0.001). The prevalence of iron deficiency (ferritin < 15 ng/mL) in H. pylori-seropositive children was significantly higher (13.9%) than in seronegative children (2.8%). This association persisted after adjusting for age and their socioeconomic status (odds ratio, 5.6; 95% confidence interval, 1.0-30.6). CONCLUSION: Serum ferritin levels are reduced in children with H. pylori infection. The H. pylori infection may lead to iron deficiency in children.

Anemia, Iron-Deficiency↗

cag pathogenicity island of Helicobacter pylori in Korean children.

BACKGROUND: cag pathogenicity island is reported to be a major virulence factor of Helicobacter pylori. The aim of this study was to investigate the status of cag pathogenicity island genes and gastric histology in Korean children with H. pylori gastritis. METHODS: Helicobacter pylori DNA was extracted from antral biopsy specimens from 25 children with H. pylori gastritis. Specific polymerase chain reaction assays were used for four genes of cag pathogenicity island. The features of gastritis were scored in accordance with the updated Sydney System. RESULTS: cagA was present in 23 (92%) of 25 children, and cagE in 24 (96%). Twenty-two (88%) children were cagT positive and 19 (76%) virD4 positive. All of the selected genes of the cag pathogenicity island were present in 17 (68%) children and completely deleted in one child. There were no differences in neutrophil activity and chronic inflammation between children infected with intact cag pathogenicity island strains and those with partially or totally deleted-cag pathogenicity island strains. CONCLUSION: cag pathogenicity island is not a uniform, conserved entity in Korea. Completeness of cag pathogenicity island may not be the major factor to determine the severity of H. pylori gastritis in children.

Adolescent↗

Early dipyridamole stress myocardial SPECT to detect residual stenosis of infarct related artery: comparison with coronary angiography and fractional flow reserve.

BACKGROUND: The detection of residual stenosis of infarct related artery (IRA) at early stage after acute myocardial infarction (AMI) is crucial in clinical decision making for interventional revascularization. The aim of this study was to evaluate the relevancy of early dipyridamole stress myocardial SPECT to detect functionally and luminologically significant residual stenosis of IRA after AMI. METHODS: Twenty five consecutive patients (M:F = 19:6, age: 56 +/- 13 yrs) with AMI underwent SPECT and coronary angiography within 5 days of the attack. Infarct related arteries with FFR < 0.75 and diameter stenosis (DST) > 70% were regarded to have functionally and morphologically significant residual stenosis. Reversible perfusion defect was defined if there was improvement of the perfusion score more than one grade in infarct segments on rest images of SPECT compared with stress images. RESULTS: Mean FFR and DST were 0.76 +/- 0.14 and 74 +/- 15%. SPECT showed no significant correlation with both FFR and DST with Kendall's coefficiency of 0.28 (p = 0.05) and 0.13 (p = 0.35). The sensitivity and specificity of SPECT to detect functionally and morphologically significant residual stenosis were 92%, 31% and 83%, 29%. CONCLUSION: The early dipyridamole stress myocardial SPECT after AMI does not seem to be a useful non-invasive test for the detection of functionally and luminologically significant residual stenosis of IRA.

Adult↗