Acute Diarrhea: Its Nutritional Consequences

The recent elucidation of etiologic agents of infantile diarrhea has markedly improved our understanding of the pathophysiology and epidemiology of acute nonbacterial gastroenteritis. In addition, the study of these agents has led to the formulation of potential strategies for the prevention and treatment of these infections. The agent of nonbacterial gastroenteritis in children which has received the most attention is human rotavirus. This agent is responsible for a large percentage of the serious cases of diarrhea which occur in children living in both developed and developing countries (3,8). However, in spite of the importance of this agent, it is clear that there are numerous episodes of serious diarrheal disease which cannot be explained by infection with rotavirus or with known bacterial agents. Studies in our population have indicated that some of these cases of gastroenteritis are caused by adenoviruses. These viruses are icosahedral, nonlipidcontaining DNA viruses, which are capable of replicating in multiple body sites, including the respiratory and gastrointestinal tracts (7). To study the role of adenoviruses in acute diarrhea, we devised enzyme immunoassays for the measurement of adenoviral antigens in stool specimens. We utilized reagents directed at hexon antigen to detect common adenoviral antigen in the stool specimens (5). We then further characterized the adenovirus by the use of reagents specifically directed at adenoviruses implicated in diarrheal disease. These adenoviruses, which have been tentatively designated adenovirus type 38 and type 39, can be distinguished from other adenoviruses by their antigenic makeup and DNA restriction patterns (6). In addition, these adenoviruses are not cultivable in human, embryonic, kidney cells and other cell lines utilized to grow adenoviruses obtained from the respiratory tract (2). These adenoviruses are, thus, similar to other viruses causing diarrhea such as rotavirus and Norwalk virus, which are difficult to cultivate in in vitro systems (1). We utilized these immunoassay systems to examine the role of adenoviruses as causes of infantile gastroenteritis in our population. We concentrated on the fall months, since previous studies in our population have documented