The involvement of precore stop codon 1896-A and base exchanges in the AT-rich region at positions 1762 and 1764 of the hepatitis B core promotor has been controversely discussed in adults with fulminant hepatitis B. Because no data are currently available on children, we analyzed the basic core promotor (BCP) and precore region in children with chronic and fulminant hepatitis B. The BCP and precore region were sequenced directly and after cloning from mothers and infants. Thirteen children suffered from chronic liver disease, 6 of whom were treated with interferon alfa (IFN-␣). All 13 patients seroconverted from hepatitis B e antigen (HBeAg) to hepatitis B e antigen antibodies (anti-HBe), and sera were analyzed before and after seroconversion. To date, the pathogenetic mechanisms leading to the different clinical courses of hepatitis B in childhood are not well understood. While babies born to hepatitis B e antigen (HBeAg)-positive mothers often develop chronic hepatitis B, infants from hepatitis B e antigen antibody (anti-HBe)-positive mothers are at risk to develop a fulminant course. Because both immunologic conditions of the host-and virus-specific factors are thought to have an important impact on the clinical course, [1][2][3] it is necessary to analyze regions relevant for viral replication. Additionally, enhanced viral protein expression has been associated with a direct hepatocytopathic effect in previous studies. [4][5][6] The hepatitis B virus (HBV) genome includes four open reading frames (pre-S/S-, precore/core-, polymerase-, and X-gene). The core promotor that is part of the X and precore region plays an important role in the viral life cycle, concerning the production of the precore and pregenomic RNA. It

Advances in endoscopy and anesthesia have enabled gastrointestinal endoscopy for children since 1960. Over the past decades, the number of endoscopies has increased rapidly. As specialized teams of pediatric gastroenterologists, pediatric intensive care physicians and pediatric endoscopy nurses are available in many medical centers, safe and effective procedures have been established. Therefore, diagnostic endoscopies in children are routine clinical procedures. The most frequently performed endoscopies are esophagogastroduodenoscopy (EGD), colonoscopy and endoscopic retrograde cholangiopancreaticography (ERCP). Therapeutic interventions include variceal bleeding ligation, foreign body retrieval and percutaneous endoscopic gastrostomy. New advances in pediatric endoscopy have led to more sensitive diagnostics of common pediatric gastrointestinal disorders, such as Crohn’s disease, ulcerative colitis and celiac disease; likewise, new diseases, such as eosinophilic esophagitis, have been brought to light.Upcoming modalities, such as capsule endoscopy, double balloon enteroscopy and narrow band imaging, are being established and may contribute to diagnostics in pediatric gastroenterology in the future.

In order to investigate the generation and selection of hepatitis B virus mutants and the influence of interferon on their evolution, a longitudinal study including 22 patients was performed. The complete preS1/S2 open reading frame was analyzed by direct sequencing from serum samples obtained before and after seroconversion to anti-HBe in 11 children without alpha-interferon treatment. Furthermore, in 11 cases with therapy additional samples obtained during interferon therapy were investigated. The comparison of each patient's preS sequences analyzed before and during therapy did not show any nucleotide change, while in both groups numerous silent and missense mutations were found immediately after seroconversion. Surprisingly, in 7 cases the hepatitis B virus changed genotype from A to D (subtype adw to ayw) after seroconversion. Additional rearrangements were observed in 4 patients. In 3 cases the selection of preS2 start codon mutants was detected after seroconversion and in 1 individual a 183-nucleotide deletion was found during and after HBeAg positivity. In conclusion, the emergence of preS rearrangements and numerous base exchanges provide evidence for a strong selection process focused against the preS region. Moreover, the appearance of genotype changes after anti-HBe seroconversion reveales a thus far unrecognized event during the natural course of HBV infection in childhood.

The emotional burden associated with chronic abdominal pain-regardless of its cause-is enormous. Interventions should target the children's coping strategies, as catastrophizing seems to be the causal link between pain and HRQOL.