Acute infectious gastroenteritis

The aetiology of diarrhoea in newborn infants

Diarrhoea is a common problem in newborn infants in hospital nurseries. In the past, sporadic diarrhoea was often attributed to dietary indiscretion by the mother, and epidemic diarrhoea was though to be caused by an unknown infectious agent. Techniques with which to locate non-cultivable viruses and untypable enteropathogenic strains of Escherichia coli allow reevaluation of the aetiology of diarrhoea in newborn infants. Preliminary results from Melbourne, Australia, suggest that most diarrhoea in newborn infants is induced by a specific infectious agent. During 1975 the agent most often identified from sporadic and epidemic diarrhoea in hospital nurseries was a reovirus-like particle ("duovirus"). Enterotoxin-producing strains of E. coli were rarely isolated. Future attempts to protect newborn infants from developing diarrhoea must be based on an accurate understanding of the aetiology of this disease.

Acute infectious diarrhea in children

Effective management of acute diarrheal disease depends on an understanding of the mechanisms and the pathogens responsible for diminished absorption of water from the intestines or increased secretion of water and electrolytes into the intestines. Initial therapy consists of fluid management, with hospitalization if dehydration is significant. Antibiotics are useful in treating specific disease entities, such as shigellosis. Careful attention to clinical status and follow-up is essential.

Treatment of infantile E. coli gastroenteritis with specific bovine anti-E. coli milk immunoglobulins

A milk immunoglobulin concentrate (MIC) containing antibodies to enteropathogenic E. coli strains was prepared by hyperimmunisation of pregnant cows and using the milk obtained during the first 6 to 8 days of lactation. The sterile concentrate contained 70 to 80% protein and 35 to 40% immunoglobulin. The antibacterial activity was measured by bacterial passive agglutination, bacteriostatic activity in vitro, phagocytic clearance in vivo, and a protection test in mice. Though differences in titers were observed, adequate immunologic activity was demonstrated by these tests. Clinical studies were performed with 60 patients (aged 10 days to 18 months) suffering from diarrhoea with isolation of enteropathogenic E. coli. They were treated for 10 days with MIC and stool cultures were done prior to, during, and 2, 3 and 4 days after termination of treatment. Among 51 patients infected with E. coli strains incorporated in the vaccine, stool cultures became negative in 43 (84.3%) after treatment with MIC and 8 remained positive. Nine patients infected with strains O 78:K80(B-) and O 114:K--(B-)--which were not included in the vaccine used for immunisation--served as controls. Only one patient in this group became negative. If all patients receiving antibiotics for non intestinal infections during the treatment period are omitted the results remained unaltered: MIC was effective in 32 out of 38 patients (84.2%). These differences were highly significant. These results provide evidence that treatment with specific MIC is effective in eliminating enteropathogenic E. coli from the intestine.

Porcine pancreatin as a source of salmonella infection in children with cystic fibrosis

Contamination of a powdered preparation of pancreatin with Salmonella schwarzengrund and S. eimsbuettel resulted in the infection of at least 31% of one group of paediatric patients with cystic fibrosis. The pancreatin contained very small numbers of Salmonellae, the infecting dose in at least one child being less than 44 organisms. More stringent bacteriological standards are needed for pharmaceuticals and foods used by paediatric patients.

Toxigenic bacterial diarrhea: nursery outbreak involving multiple bacterial strains

An outbreak of watery diarrhea occurred in 14 of 15 infants in a special care unit over a four-day period. Using the CHO cell assay for enterotoxin, we found that 11 of these patients had toxigenic bacteria in their stools. These bacteria comprised nine different serotypes of three species of organisms: Escherichia coli, Klebsiella, and Citrobacter. None of the three serotypes of E. coli were classic enteropathogenic serotypes. Rectal swab specimens from all 15 infants were examined for the presence of viruses by electron microscopic and cell culture techniques as well as by studies in suckling mice. None had parvovirus- or reovirus-like agents and two had adenoviruses. No other viral agents were detected. Of 38 bacterial strains isolated from ten control infants without diarrhea, three Klebsiella strains from two individuals were found to be toxigenic. Analysis of a total of 136 enteric isolates showed that toxigenicity as measured by the CHO assay was strongly associated with strains isolated during acute diarrheal illness when compared with strains isolated in convalescence (p less than 10(-5)) or with strains from control infants without diarrhea (p less than 10(-5)). This study raises the possibility of an outbreak of disease caused by a transmissible plasmid responsible for a cholera-like enterotoxin production in several enteric bacterial strains.

Enterotoxin-producing bacteria and parasites in stools of Ethiopian children with diarrhoeal disease

Enterotoxinogenic bacteria were isolated from 131 (37%) of 354 Ethiopian infants and children with acute gastrointestinal symptoms. Only one of these isolates belonged to the classical enteropathogenic serotypes of Esch. coli. Two colonies from each patient were isolated and tested for production of enterotoxin by the rabbit ileal loop test, the rabbit skin test, and an adrenal cell assay. However, only 38% of the isolated enterotoxinogenic strains were Esch. coli; the others belonged to Klebsiella, Enterobacter, Proteus, Citrobacter, Serratia, and Aeromonas. In 18 patients both isolates were toxinogenic and belonged to different species. The incidence of intestinal parasites was 35% with no apparent correlation to the occurrence of toxinogenic bacteria in the stools.

[Old and new data on diarrhetic diseases in childhood I. Etiology and pathophysiology]

Etiology and Pathophysiology. The present article is a comprehensive review of recent research results in the field of acute diarrhea. The most important new idea in contrast to older views is that almost all acute diarrheas are associated with a disturbance of intestinal bacterial homeostasis: overgrowth of the small intestine with apathogenic or pathogenic organisms is followed by changes in intestinal metabolism with increase in intestinal water and electrolyte secretion. Anaerobic organisms cause by enzymatic deconugation and dydroxylation of bile acids secretion of fluid into the small intestine and inhibition of fluid absorption from the large intestine. 10-OH-fatty acids, which are formed intraluminally by enzymatic hydroxylation of long-chain unsaturated fatty acids from the diet by similar anaerobic organisms, produce profuse secretion of fluid into the small intestine. The ability of numerous strains of E. coli to produce enterotoxin, which has a qualitatively similar action to cholera toxin, is now considered to be a major cause of infantile diarrhea. The separation of two completely different pathophysiologic mechanisms of E. Coli, the enterotoxic and the enteroinvasive action which are determined by extranuclear chromosomal material, is an important result of recent research. Overgrowth of the small intestine with different bacteria is followed by loss of actiivity of lactase, and later of all disaccharidases in the intestinal mucosa.