Diarrheal diseases are major causes of morbidity, with attack rates ranging from two to 12 or more illnesses per person per year in developed and developing countries. In addition, diarrheal illnesses account for an estimated 12,600 deaths each day in children in Asia, Africa, and Latin America. The causes of diarrhea include a wide array of viruses, bacteria, and parasites, many of which have been recognized only in the last decade or two. While enterotoxigenic Escherichia coli and rotaviruses predominate in developing areas, Norwalk-like viruses, Campylobacter jejuni, and cytotoxigenic Clostridium difficile are seen with increasing frequency in developed areas; and Shigella, Salmonella, Cryptosporidium species, and Giardia lamblia are found throughout the world. The rational management of infectious diarrhea requires the highly selective use of laboratory tests for these varied etiologic agents, depending on the clinical and epidemiologic setting. The purpose of this review is to provide an overview of the magnitude, special settings, and etiologies of diarrhea endemic to developed and developing countries. This information permits a practical approach to the diagnosis and management of common diarrheal illnesses in different settings.
PIP: Diarrhea is the 2nd most frequent illness in the world. In a study done in Cleveland, Ohio from 1948-1957, researchers learned that people had diarrhea an average of 1.52 times annually. The age specific attack rates climbed from 1 episode/child 1 year old/years to 2-2.2 episodes/child 1-10 years old/year. In similar study in Charlottesville, Virginia between August 1975-July 1977, the overall diarrhea attack rate stood at 1.9 episodes/person/year and, for children 3 years old, it was 2.5 episodes/year. The incidence of diarrhea peaked in the winter months, unlike developing countries where it peaks in the summer months. In developing countries, attack rates range from 5-12 episode/child/year with the highest rates in the 1st 2 years of life (e.g., in India among the urban poor, 18.6 episodes/child/year. diarrhea stands as the leading cause of death in developing areas. Even though oral rehydration therapy is reducing the morality rate from acute diarrhea in developing countries, prolonged episodes of diarrhea of 14- 20 days continue to claim children's lives. In developed countries, diarrhea poses a distinct problem to hospitals, nursing homes., and day care enters. For example, researchers revealed 7.7 cases of nosocomial diarrhea/100 admissions in the medical intensive care unit at the University of Virginia Hospital. About 33% of the elderly patient in extended care facilities have a serious diarrheal illness each year. Reports show that attack rates among children in child care facilities range from 17-100% with considerable secondary attack rates in the children's families. People with AIDS often experience diarrhea which for them is often fatal. In the United State, 50-60% of them have it at diagnosis while in Africa and Haiti the percentage is 95%.