Understanding Diarrhea: Causes, Types, and Consequences, Exercises of Law

Download Understanding Diarrhea: Causes, Types, and Consequences and more Exercises Law in PDF only on Docsity! The greatest volume of intestinal water is absorbed in the small bowel the colon concentrates intestinal contents against a high osmotic gradient. What are the three types of diarrhea in terms of duration? Acute watery diarrhea, invasive (bloody) diarrhea, and chronic diarrhea (persistent ≥14 days). What is the difference between dysentery and bloody diarrhea? Dysentery is characterized by frequent small stools containing visible blood, often accompanied by fever, tenesmus, and abdominal pain, while bloody diarrhea refers to larger volume bloody stools with less systemic illness. Why are prolonged and persistent diarrhea important? Prolonged (lasting 7-13 days) and persistent diarrhea (lasting 14 days or longer) are important because of their impact on growth and nutrition. What are the potential consequences of recurrent, prolonged, or persistent diarrhea in young children? Diarrheal illnesses, especially episodes among young children that are recurrent, prolonged, or persistent, can be associated with malnutrition, stunting, micronutrient deficiencies, and significant deficits in psychomotor and cognitive development. What is secretory diarrhea? Secretory diarrhea occurs when the intestinal mucosa directly secretes fluid and electrolytes into the stool and is the result of inflammation (e.g., IBD, chemical stimulus). How is cholera-induced diarrhea different from other types of diarrhea? Cholera-induced diarrhea is a secretory diarrhea that is stimulated by the enterotoxin of Vibrio cholerae, which causes increased levels of cyclic adenosine monophosphate (cAMP) within enterocytes and leads to secretion into the small-bowel lumen. What is the difference between secretory and osmotic diarrhea? Secretory diarrhea is usually of large volume and persists even with fasting, while osmotic diarrhea occurs after ingestion of a poorly absorbed solute and is usually of lesser volume than a secretory diarrhea and stops with fasting. What is the most common cause of acute diarrhea in children worldwide? Rotavirus. What is the most common cause of acute gastroenteritis (AGE) among children worldwide? Rotavirus. What are the two genera of Caliciviruses that cause AGE? Norovirus and sapovirus. Which serotypes of adenovirus are most often associated with diarrhea? 40 and 41. What are the major bacterial pathogens that cause AGE? Nontyphoidal Salmonella (NTS), Shigella, Campylobacter, and Yersinia. What are the five pathotypes of Escherichia coli that infect humans? Shiga toxin-producing (STEC), enterotoxigenic (ETEC), enteropathogenic (EPEC), enteroaggregative (EAEC), and enteroinvasive (EIEC). Which serogroups of Vibrio cholerae produce epidemic cholera? O1 and O139. Which bacterial pathogens cause foodborne illness due to their ability to produce emetic and/or enterotoxins? Bacillus cereus, Clostridium perfringens, and Staphylococcus aureus. Which parasites cause AGE? Giardia intestinalis, Cryptosporidium spp., Cyclospora cayetanensis, and Entamoeba histolytica. What are the most common parasites that cause diarrhea? Giardia intestinalis, Cryptosporidium spp., Cyclospora cayetanensis, and Entamoeba histolytica. What are the most common pathogens attributed to moderate-to-severe diarrhea in low- and middle-income countries? Rotavirus, Cryptosporidium, Shigella, and ETEC producing heat-stable toxin (ST) either alone or in combination with heat-labile toxin (LT), herein termed ST-ETEC, and, to a lesser extent, adenovirus 40 and 41. What are some etiologic agents that are common causes of AGE in high-resource settings but have low frequency in resource-limited settings? NTS, STEC, norovirus, and C. difficile toxin. Which three agents are associated with most deaths among children under 5 years? Rotavirus (29%), Cryptosporidium (12%), and Shigella (1%). What are the three agents associated with most deaths among children under 5 years old? Rotavirus, Cryptosporidium, and Shigella. What are the examples of local invasion caused by NTS? Mesenteric adenitis, appendicitis, and rarely cholecystitis, mesenteric venous thrombosis, pancreatitis, hepatic, or splenic abscess. What are the extraintestinal invasive infections that can result from bacteremic spread of NTS? Pneumonia, osteomyelitis, meningitis (3 conditions seen most commonly with NTS), abscesses, cellulitis, septic arthritis, and endocarditis. What is the most common symptom associated with S. aureus and B. cereus emetic toxin? Vomiting. What are the noninvasive contiguous infections caused by Shigella? Vaginitis and urinary tract infections. What are the clinical syndromes associated with fatal cases of C. difficile toxin? Toxic megacolon, systemic toxicity, and multisystem organ failure, possibly related to systemic absorption of toxin. What are the major manifestations of S. aureus and B. cereus emetic toxin? A vomiting illness. What are the major manifestations of C. perfringens and B. cereus enterotoxins? Diarrhea. How long do illnesses due to intestinal protozoa tend to be? More prolonged, sometimes for 2 weeks or more. What should be suspected when there is a prolonged diarrheal illness characterized by episodes of sometimes-explosive diarrhea with nausea, abdominal cramps, and abdominal bloating? A protozoal etiology. What are the major complications from diarrhea from any cause? Dehydration and electrolyte or acid-base derangements, which can be life-threatening. What are the potential complications of prolonged or persistent episodes of diarrhea in children? Poor growth and nutrition, secondary infections, and micronutrient deficiencies such as iron, zinc, and vitamin A. What is the importance of ensuring continued nutritional support during diarrheal episodes? Prolonged limitation of the diet may extend diarrheal symptoms. What is the most common cause of viral acute gastroenteritis (AGE)? Viral AGE illnesses are usually self-limited and resolve after several days. What is intussusception, and how is it triggered by viral AGE? Intussusception is a rare complication of viral AGE where lymphoid hyperplasia is associated with it. What are the potential complications of bacterial AGE in malnourished children and HIV-infected populations? Bacteremia is a well-recognized complication, which can result from local or systemic spread of the organism. What are the potential complications of Shigella-associated diarrhea in developing countries? Toxic megacolon, intestinal perforation, and rectal prolapse can occur. What is the most common complication of pediatric diarrhea in the United States? Hemolytic uremic syndrome (HUS), which is the leading cause of acquired renal failure in children, developing in 5-10% of patients infected with STEC. What is the leading cause of acquired renal failure in children in the United States? HUS. What are the risk factors for HUS? Age 6 months to 4 years, bloody diarrhea, fever, elevated leukocyte count, and treatment with antibiotics and antimotility agents. What is a notable complication of Yersinia and sometimes Campylobacter? Pseudoappendicitis secondary to mesenteric adenitis. Who is most often affected by pseudoappendicitis? Older children and adolescents. What are the symptoms of pseudoappendicitis? Fever and abdominal pain with tenderness localized to the right lower quadrant, with or without diarrhea, and can be confused with appendicitis. What are the immune-mediated complications that are more often seen in adults than children? Reactive arthritis following infection with the classical bacterial enteropathogens and Guillain-Barré syndrome following Campylobacter infection. What can protozoan illnesses lead to in young and immunocompromised individuals? Poor weight gain. What are the potential consequences of persistent protozoan illnesses in young and immunocompromised individuals? Poor weight gain, weight loss, malnutrition, or vitamin deficiencies. What are the potential consequences of Entamoeba infection? Severe ulcerating colitis, colonic dilation, and perforation. How does Entamoeba infection spread systemically? Most commonly causing liver abscesses.