Development of RT-PCR Method to Detect Various Human Enteric Viruses

Human enteric viruses are one of the major causes of acute gastroenteritis outbreaks. A rapid and precise detection of virus is critical for prompt diagnosis. For this purpose, nucleic acid-based techniques such as reverse transcription (RT)-PCR have been developed. Although RT-PCR is a rapid, specific and sensitive method to detect virus, many steps or reactions are required, especially when various types of viruses are targeted. In this study, we developed a quick and effective method to detect human enteric viruses with a few reactions. Our candidate viruses were as follows: one DNA virus (adenovirus: AdV) and seven RNA viruses including poliovirus (PV), coxsackievirus A (CoxA) and B (CoxB), human rotavirus (HRV), hepatitis A virus (HAV), norovirus (NorV), and astrovirus (AstV). With this amount of samples, theoretically, a total of fifteen biomolecular reactions have to be performed, which include seven RT reactions and eight subsequent PCR with specific primers in each case. Specific primers, enterovirus universal primers, and random primers were applied independently to compare the outcomes of RT and PCR steps in each viral sample. We found that random 9-mer is ideal for the RT reactions of RNA viruses with negligible differences in sensitivity and specificity of viral detection except HRV. Hence, HRV cDNA generated by HRV-specific primer and AdV DNA were amplified in a single tube by duplex PCR. The cDNAs generated by RT using random 9-mers were divided into two reaction tubes without losing sensitivity: one duplex PCR detects enteroviruses (PV, CoxA, CoxB) and HAV, the other detects NorV and AstV. In conclusion, it is possible to detect eight enteric viruses with a substantially reduced number of reactions, which are composed of five reactions, two RT and three PCR reactions.

Efficacy of Hepatitis B Immune Globulin for Prevention of De Novo Hepatitis B in Living-related Liver Transplantation / 대한소아소화기영양학회지

PURPOSE: Hepatic allografts from donors with hepatitis B core antibody have been demonstrated to transmit hepatitis B virus (HBV) infection to recipients after liver transplantation (LT). The efficacy of hepatitis B immune globulin (HBIg) to prevent de novo hepatitis B was investigated by comparing active immunization in the early phase to HBIg monotherapy in the late phase of pediatric liver transplants at Samsung Medical Center. METHODS: Among pediatric liver transplants, from May, 1996 to June, 2002, 15 recipients who were hepatitis B surface antigen (HBsAg) (-) received an allograft from a donor with hepatitis B core antibody (HBcAb) (+). Except two who died from unrelated causes, eleven of 13 recipients were HBsAb (+), and 2 were naive (HBsAb(-), HBcAb(-)). All patients were vaccinated for HBV before LT. In the early phase (January, 1997~November, 1997, 3 patients), HBsAb (+) recipients received booster vaccination after LT. In the late phase (December, 1997~, 10 patients), all recipients were given booster vaccination and received HBIg therapy in order to maintain HBsAb titer greater than 200 IU/L. Lamivudine was given in one case because of severe side effect of HBIg. We retrospectively analyzed the effect of the preventive therapy for de novo hepatitis B through medical records. RESULTS: De novo hepatitis B developed in three of 13 recipients (23.1%). All of 3 patients who received active immunization in the early phase became HBsAg (+) at 7~19 months after transplantation. One of them was naive before LT and the other two were HBsAb (+). All of 10 recipients who were given HBIg in the late phase remained HBsAg (-) at 7~55 months' follow-up. CONCLUSION: Passive immunization with HBIg was effective for prevention of de novo hepatitis B in HBsAg (-) recipients of hepatic allografts from HBcAb (+) donors.

The Relationship between Helicobacter pylori Infection and Iron-Deficiency: Seroprevalence Study in 937 Pubescent Children / 대한소아소화기영양학회지

PURPOSE: The purpose of this study was to investigate the relationship between Helicobacter pylori (H. pylori) infection and iron-deficiency anemia in pubescent children, susceptible to iron deficiency due to the high iron requirements for growth. METHODS: Hemoglobin, serum iron, total iron-binding capacity, serum ferritin, and serum IgG antibodies to H. pylori were measured in 937 children (475 boys and 462 girls). Their ages ranged from 10 to 18 years. The prevalences of H. pylori infection were compared between groups, based on the presence or absence of anemia, hypoferritinemia, iron deficiency, and iron-deficiency anemia. The levels of hemoglobin, serum iron, total iron-binding capacity, transferrin saturation, and serum ferritin were obtained according to the presence or absence of H. pylori infection. RESULTS: The prevalences of anemia, iron deficiency, iron-deficiency anemia, and H. pylori infection were 8.1%, 9.1%, 3.1%, and 20.8%, respectively. The H. pylori-positive rates in anemia, hypoferritinemia, and iron-deficiency group were 34.2%, 29.5%, and 35.3%, respectively, compared to 19.6% in the non-anemia group, 19.2% in the non-hypoferritinemia group, and 19.4% in the non-iron deficiency group. The H. pylori-positive rate in the iron-deficiency anemia group was 44.8% in comparison with 20.0% in the non-iron-deficiency anemia group. Hemoglobin and iron levels did not show any significant differences between the H. pylori-positive and -negative groups, whereas the serum ferritin level decreased significantly in the H. pylori-infected group. CONCLUSION: H. pylori infection is thought to be associated with iron deficiency in pubescent children.

Clinical Characteristics and Treatment Outcome of Pediatric Patients with Burkitt Lymphoma / 대한소아혈액종양학회지

PURPOSE: Burkitt lymphoma (BL) occurs mainly in pediatric populations. Data on the clinical characteristics and treatment results are scarce in Korea. We report our single center experience on BL in children to improve the treatment efficacy while minimizing treatment-related toxicities. METHODS: We undertook a retrospective analysis of 15 patients diagnosed as BL or Burkitt leukemia-lymphoma (BLL) between Aug., 1995 and Feb., 2002. Several induction chemotherapy regimens were used including CCG 106B (prednisolone, cyclophosphamide, daunorubicin, vincristine, L-asparaginase; N=10). Post-induction regimens consisted of CCG 106B (N=12), high dose chemotherapy and autologous stem cell transplantation (N=1), and others (N= 2). RESULTS: The incidence of BL and BLL was 27.2% of Non-Hodgkin's lymphoma diagnosed at our institution. Abdominal mass was the most common presentation (80%) and many patients had advanced stage diseases. Six patients suffered from tumor lysis syndrome, all of whom eventually improved. None died from infection or bleeding. All patients are alive disease-free for median 20 months (range 2~26 months) of follow-up duration except for one who is alive with a residual liver mass. CONCLUSION: Though recent therapeutic trials of repeated intensified chemotherapy including high dose cytarabine and methotrexate led to improvement of survival in patients with BL, many patients suffers from therapy-related toxicities. We successfully treated pediatric BL patients with tolerable toxicities using CCG 106B regimen which is known to be highly effective in high-risk acute lymphoblastic leukemia. More experiences are needed to establish the optimal duration of therapy.