Gastrointestinal and liver infections
Michael JG Farthing, Anne B Ballinger in Drug Therapy for Gastrointestinal and Liver Diseases, 2019
Prolonged carriage of an enteropathogen is well-recognized in bacterial, viral, protozoal and helminth intestinal infections. Asymptomatic carriage of Salmonella spp. is probably the most common example of carriage of a bacterial enteropathogen. In the majority of patients, stool cultures become negative within 12 weeks but, in some stool cultures, may remain positive for 6-12 months or longer. This human reservoir of infection is particularly important in food handlers, healthcare workers and workers in day-care centres. Eradication of Salmonella spp. can be achieved in more than 80% of cases by administration of amoxycillin or a quinolone for 4-6 weeks at standard doses. Long-term asymptomatic carriage is also recognized to occur with many other bacterial enteropathogens including Camplyobacter jejuni, Yersinia enterocolitica and Clostridium difficile.
Interlocking Inequalities Related to Water and Sanitation, Nutrition and Healthcare Access
Oliver Cumming, Tom Slaymaker in Equality in Water and Sanitation Services, 2018
EED is associated with poor sanitary conditions and chronic enteric pathogen exposure and is characterized by immune responses that cause inflammation and alter gut structure and function. These changes occur at the cellular level of the small intestine wall, including broadened villi structure, increased permeability, and mucosal inflammation.25 In addition to loss of fluids from diarrhea, the child’s body is not able to absorb the nutrients necessary for growth or for full immune system function, resulting in higher severity of future infection and increased risk of mortality.26 Muscosal inflammation is a defense against enteropathogen colonization, but it can also prevent growth of beneficial microbes, allowing enteropathogens with survival mechanisms to thrive.22 Proinflammatory cytokines are also directly linked to inhibition of the growth hormone–insulin-like growth factor (GH–iGF-i) axis, which is critical for linear growth.27,28
Gastrointestinal disorders
Anne Lee, Sally Inch, David Finnigan in Therapeutics in Pregnancy and Lactation, 2019
Most gastrointestinal infections result in some form of gastroenteritis, with alteration of bowel habit (usually towards diarrhoea), abdominal discomfort, cramps or pain, nausea and/or vomiting. They are usually self-limiting and best treated with supportive measures. If symptoms are prolonged for more than 24–48 hours, stools should be examined for ova, cysts and parasites and microbial culture. Many episodes are due to enterotoxins or viruses, neither of which respond to antibiotics, which are best avoided even for proven bacterial infections. There is no indication for the routine use of antibiotics for gastrointestinal infections in pregnancy. By the time culture results are available the illness is often over, but it is important to monitor such infections for public health reasons.
Antimicrobial resistance in enteric bacteria: current state and next-generation solutions
Published in Gut Microbes, 2020
M. J. Wallace, S. R. S. Fishbein, G. Dantas
Invasive enteropathogens do not typically occupy the human microbiome as commensal species, and upon pathogenesis they can inflict acute intestinal distress including gastroenteritis, inflammation, and diarrhea. If not treated properly, extensive morbidities such as dehydration, bacteremia, shock, and even death may ensue.50 Diarrheal disease accounts for over 1.6 million deaths worldwide and is one of the top five causes of mortality for children under five.51 Many of these diseases are endemic to specific regions, but increased globalization has accelerated international transmission of MDROs.2 Furthermore, common reservoirs of infection include water sources, food, and animals (Figure 1a).2 Invasive enteropathogens employ diverse mechanisms of AMR, which exacerbate the associated burdens on human health and the economy.1
Mapping of aetiologies of gastroenteritis: a systematic review and meta-analysis of pathogens identified using a multiplex screening array
Published in Scandinavian Journal of Gastroenterology, 2020
Jeremy Meyer, Elin Roos, Christophe Combescure, Nicolas C. Buchs, Jean-Louis Frossard, Frédéric Ris, Christian Toso, Jacques Schrenzel
The American College of Gastroenterology recommends performing microbiological assessment of the stools in patients with dysentery, moderate-to-severe gastroenteritis and in those with symptoms lasting for more than seven days. Other patients should receive either supportive treatment only or empiric antibiotics. Of note, the recommendation indicates that ‘use of antibiotics for community-acquired diarrhea should be discouraged as epidemiological studies suggest that most community-acquired diarrhea is viral in origin’ [6]. Moreover, giving antibiotics in patients with E. coli O157 infection might induce a severe form of hemolysis and precipitate renal failure. Noteworthy, the American College of Gastroenterology considers traditional methods of diagnosis, such as bacterial culture, microscopy and antigen testing, to be of low analytical sensitivity for the detection of enteropathogens causing gastroenteritis [6]. For instance, a multicentre cohort including 30,000 stool cultures identified a bacterial pathogen in only 5.6% of samples [7]; a result that questions the cost-effectiveness of stool cultures. In addition, the diversity of organisms able to cause gastroenteritis constitutes a limitation for single pathogen-targeted molecular-based detection methods.
Pathobionts: mechanisms of survival, expansion, and interaction with host with a focus on Clostridioides difficile
Published in Gut Microbes, 2021
Harish Chandra, Krishna Kant Sharma, Olli H. Tuovinen, Xingmin Sun, Pratyoosh Shukla
It is widely known that microbiota protect against enteropathogen infections. In contrast, how enteropathogens may play a role in dysbiosis of the gut microbiota is poorly understood. Embedded in a matrix of extracellular polymeric substances in the intestinal mucus, gut microbiota predominantly consist of a complex of poly-microbial biofilms, which may disperse free-swimming bacteria as well.38 Pathobionts under conditions of a physiological disturbance may slough off from the biofilms, thus leading to inflammation. It has been observed that the inflammatory IBD complications in patients are exacerbated after enteropathogen infections due to dysbiotic gut.11 Enteropathogens such as Giardia duodenalis perturb the beta diversity of the microbiota and increase the abundance of Firmicutes like Clostridiales by disrupting the microbial biofilm polysaccharide matrix, thereby releasing the pathobiont.11,38 There are other enteropathogens like Campylobacter jejuni that has been shown to activate latent virulence genes of fimbriae, flagella, and hemolysin E in noninvasive E. coli, thus facilitating adherence and translocation through the epithelial barrier.39