Infectious diseases of gastrointestinal tract in adolescents.

This article reviews the following gastrointestinal infections: esophagitis, gastritis, duodenitis including duodenal ulcers, and enteritis (gastroenteritis). The epidemiology, risk factors, microbiology and pathogenesis, diagnosis, treatment, morbidity/mortality, and prevention are discussed in relation to the most important pathogens. The symptoms and pathogenesis of esophagitis caused by Candida albicans and herpes simplex are contrasted with the symptoms of esophagitis caused by Helicobacter pylori and gastroesophageal reflux disease (GERD). The incidence of gastritis and gastric and duodenal ulcers caused by H. pylori is discussed. The treatment regimens of H. pylori infection recommended by the CDC are presented. Endoscopic findings in esophagitis, gastritis, and duodenal ulcers are presented and discussed. The difference in symptoms caused by viral agents (Norwalk virus), bacterial agents (enterotoxigenic E. coli), and parasites (Giardia lamblia and Cryptosporidium parvum) are compared and contrasted. The symptoms of infections of the terminal small bowel caused by Salmonella and Campylobacter jejuni and the symptoms of pure colonic infection, dysentery, caused by Shigella and enteroinvasive E. coli and Entamoeba histolytica are discussed. The treatment regimens for enteritis are presented.