Immunonutrition.

Nutrition and immunology are interrelated. Several nutrients like arginine, glutamine, omega-3-fatty acids and nucleotides enhance cellular immunity, modulate tumor cell metabolism and improve clinical outcome in stress situations. Glutamine supplementation has been shown to decrease incidence of sepsis and to reduce length of hospital stay in bone marrow transplant patients, low birth weight infants, surgical and multiple trauma patients. Studies with arginine have shown a reduction in infectious complications and lower mortality, however a better understanding of the biology of arginine is needed. Omega-3-fatty acid supplimentation as in fish oil stimulates the immune system. The beneficial effects of immunonutrition in surgical patients has been demonstrated in several studies. It significantly reduces infectious complications and length of hospital stay. In critically ill patients immunonutrition may decrease infectious complications but it is not associated with a mortality advantage. Pediatric experience is limited, but the future is promising.

Hepatitis C in childhood.

The prevalence of hepatitis C virus (HCV) infection is relatively low in childhood. Blood transfusion has been the principal route of acquisition in children but vertical transmission is gradually occupying primacy in the developed world. The risk of vertical transmission increases with higher maternal viraemia and human immuno-deficiency virus (HIV) co-infection but current international guidelines do not suggest avoidance of vaginal delivery and breastfeeding to minimise the risk of vertical transmission. The diagnosis of perinatal transmission is different from that in older child or adult and detection of HCV-RNA is essential. Although the natural history of HCV infection in children is not well characterised, almost 50-80% will progress to chronic hepatitis among vertically infected and blood transfusion acquired hepatitis C cases. Children have a lower viral load, lower ALT values and milder histological derangement as compared to adults with chronic hepatitis C cases. Experience of treatment of chronic hepatitis C in children is limited and still evolving. Few patients achieve spontaneous remission and progression to a more severe liver disease might occur in adult life. Here, the natural history, diagnosis and management of HCV infection in children are discussed with special emphasis on features which are different from adults.

Liver transplantation in the developing world.

Liver transplantation is an accepted therapy for acute and chronic liver failure. Advances in preoperative and postoperative management and surgical techniques have extended the indications and improved results. Most international centres report one year actual survival rates of between 58-90% and 5-8 years survival of 75-80%. These developments, however, have been limited largely to the West. While the need for liver transplantation is well recognised in the developing world, liver transplantation has only recently been performed successfully in India. This article examines the challenges of liver transplantation in the developing world.

Helicobacter pylori in children.

Helicobacter pylori (Hp) infection is one of the most frequently encountered bacterial infections worldwide. Although strong epidemiological association exists between Hp infection and duodenal and gastric ulcers and gastric cancer in adults, the clinical spectrum of Hp infection in children is yet to be established. The increasing use of endoscopy as a diagnostic modality in gastroduodenal diseases in children has raised some questions regarding the role of Hp in causing symptoms in children and need for eradication therapy. Despite a variety of protocols, the standard therapy of Hp in children is still undecided. This article discusses the epidemiological and clinical spectrum of Hp infection in children and includes a review of various diagnostic modalities and treatment protocols for this infection.