Diarrheal Syndrome Flashcards
What does diarrheal syndrome include?
- 3 or more bowel movements
- fecal masses with changed consistency, color, smell, +/- pathologic admixtures of mucus and/or blood
What are the criteria for infectious diarrhea?
- the presence of acute diarrheal syndrome (upto 14 days)
- one or more of the following symptoms:
abdominal pain
nausea
vomiting
tenesmus in combination with toxiinfectious syndrome
and/or epidemiological findings
What are the different causative agents?
Bacterial: E. Coli, Campylobacter, Shigella species, Vibrio cholera, Salmonella
Viral: Rotavirus, Human calicivirus, adenovirus
Parasitic: Cryptosporidium parvum, Giardia intestinalis, entamoeba histolytica, cyclospora cayetanensis
Which are the main E.Coli species that produce diarrheal syndrome?
- Enterotoxigenic E. coli (ETEC)
- Enteropathogenic E. coli (EPEC)
- Enteroinvasive E. coli (EIEC)
- Enterohemorrhagic E. coli (EHEC)
- Enteroaggregative E. coli (EAggEC)
Which strain of E.Coli causes traveler’s diarrhea?
- Enterotoxigenic E. coli (ETEC)
Which strain of E.coli rarely causes disease in adults?
Enteropathogenic E. coli (EPEC)
Which strain of E.coli causes bloody mucoid (dysentery) diarrhea?
Enteroinvasive E. coli (EIEC)
Which strain of E.coli causes bloody diarrhea, severe hemorrhagic colitis, and hemolytic uremic syndrome in 6–8% of cases?
Enterohemorrhagic E. coli (EHEC)
Which strain of E.coli causes watery diarrhea in young children and persistent diarrhea in children with human immunodeficiency virus (HIV)?
Enteroaggregative E. coli (EAggEC)
Which are the main sources of Campylobacter infections in developed countries?
Poultry
Which are the main sources of Campylobacter infections in developing countries?
Asymptomatic infection is very common in developing countries and is associated with the presence of cattle close to dwellings
What clinical signs can be seen in campylobacter infection?
- watery diarrhea
- dysentery
- Guillan Barre syndrome (1/1000 cases of campylobacter infections in developed countries)
Is campylobacter infection common in children in developing countries?
yes
Campylobacter is one of the most frequently isolated bacteria from the feces of infants and children in developing countries, with peak isolation rates in children 2 years of age and younger
What are the common disease-causing species of shigella?
- S. sonnei (developed countries)
- S. flexneri (developing countries)
- S. dysenteriae type 1 (Sd1) (only serotype that produces Shiga toxin)
Which age group is mainly affected by Shigella infections (in developing countries)?
An estimated 160 million episodes occur in developing countries, primarily in children
It is more common in toddlers and older children than in infants
Which serotypes of the vibrio cholerae species are pathogenic for humans?
All serotypes
Which serotypes cause severe cholera?
V. cholerae serogroups O1 and O139 are the only two serotypes that cause severe cholera, and large outbreaks and epidemics
What can happen if proper rehydration is not given in a vibrio cholera infection?
In the absence of prompt and adequate rehydration, severe dehydration leading to hypovolemic shock and death can occur within 12–18 h after the onset of the first symptom
What is the profile of the stools in a vibrio cholerae infection?
Stools are watery, colorless, and flecked with mucus; often referred to as “rice water” stools
Which serotypes of salmonella cause enteric fever?
Enteric fever — Salmonella enterica serovar Typhi and Paratyphi A, B, or C (typhoid fever);
fever lasts for 3 weeks or longer; patients may have normal bowel habits, constipation or diarrhea
What are the main reservoirs for Salmonella?
Animals are the major reservoir for salmonellae
Humans are the only carriers of typhoidal Salmonella
What are the clinical symptoms of nontyphoidal salmonellosis?
(Salmonella gastroenteritis), there is an acute onset of nausea, vomiting, and diarrhea that may be watery or dysenteric in a small fraction of cases
Fever develops in 70% of affected children
Bacteremia occurs in 1–5%, mostly in infants