Acute gastroenteritis Flashcards
Could be also known as:
*Acute Enterocolitis
*Acute Gastroenterocolitis
*Acute Diarrhea
*Acute Diarrheal Disease
ACUTE DIARRHEA–
generally defined by stool consistency and duration
(less than 7 days) (not by the number of stools per day – infant
variability)
- EXTENDED DIARRHEA (7-14 DAYS)
- CHRONIC/PERSISTENT DIARRHEA – More than 14 days
The causes of acute diarrhea (modified and adapted after Ciofu E, Ciofu
C. Pediatria - Tratat 1st Edition, 2001 )
1. Enteral infections (bacterial, viral, parasitic)
2. Parenteral infections (UTI, etc)
3. Inflammatory intestinal disease
4. Anatomical/functional causes (short intestine, de l’anse borgne
syndrome, etc)
5. Pancreatic/hepatic diseases (cistic fibrosis, etc)
6. Biochemical causes(disaccharides deficit, chloride diarrhea)
7. Celiac disease
8. Neoplasia (lymphoma, neuroblastoma, etc)
9. Immunodeficiency (hypogammaglobulinemia, Iga selective deficiency,
AIDS)
10. Endocrinopathy (hyperparathyroidism , Addison’s disease)
11. Malnutrition
12. Diet factors (over-alimentation, introduction of new foods)
13. Alimentary intolerances/allergies
14. Psychogenic diseases (irritable bowel)
15. Toxic diarrhea (heavy metal poisoning)
The causes of acute diarrhea (from a
practical point of view)
- Enteral infections
- bacterial
- viral
- Parasitic
- Parenteral infections (UTI, etc)
- Medication (antibiotics, etc)
- Alimentary allergies
- Food factors (over-alimentation, introduction of new
foods)
There are many pathogenetic mechanisms that are both
self-explanatory and asociated with acute diarrhea:
- Secretory - secretagogue agents, ex. cholera toxin, which
attach to the receptors of the intestinal ephitelium and
determine an intracellular accumulation of cAMP and cGMP
Osmotic – determined by unabsorbable solutions,
carbohydrate malabsorption (caused by the damage of the
small intestine’s brush border)
*Intestinal motility disorders – ex thyrotoxicosis, bacterial
overgrowth (the transit is slowed down)
*Reduce intestinal surface (short intestinal syndrome)
*Mucosal invasion (inflammation, decreased colonic
reabsorption, increase motility)
There are many pathogenetic mechanisms that are both
self-explanatory and asociated with acute diarrhea:
- Secretory - secretagogue agents, ex. cholera toxin, which
attach to the receptors of the intestinal ephitelium and
determine an intracellular accumulation of cAMP and cGMP
Osmotic – determined by unabsorbable solutions,
carbohydrate malabsorption (caused by the damage of the
small intestine’s brush border)
*Intestinal motility disorders – ex thyrotoxicosis, bacterial
overgrowth (the transit is slowed down)
*Reduce intestinal surface (short intestinal syndrome)
*Mucosal invasion (inflammation, decreased colonic
reabsorption, increase motility)
Practical differential diagnosis: osmotic
diarrhea e secretory diarrhea
Parameters Osmotic Diarrhea Secretory Diarrhea
Stool Volume < 200 ml/day > 200 ml/day
Answer to fasting Answer No answer
Stool Na < 60 mOsm/l > 90 mOsm/l
Fecal osmolarity < plasma osmolarity = plasma osmolarity
Definition acute gastroenteritis (AGE)
*Decrease of fecal consistency (soft or liquid) and/or
increase of stool evacuation frequency (tipically ≥3/24
hours) with or without fever and vomiting
* A change in stool consistency versus previous stool
consistency is more indicative of diarrhea than stool
number, particularly in the first months of life
Pathogeny- AGE
- Enterotoxigenic Mechanism - major pathogenic
mechanism (if not exclusive) production of
enterotoxin and its action on the intestinal mucus,
with the distruction of villus cells - Enteroinvasive mechanism - direct invasion of the
intestine, as well as cytokines production that
causes the increase of water secretion and
electrolytes in the intestinal lumen.
*The main pathogenic mechanism
consists in
blocking or decrease water and electrolytes absorption at the intestinal level
Epidemiology
- The incidence of diarrhea ranges from 0.5 to 2 episodes
per child per year in children <3 years in Europe. - Gastroenteritis is a major reason for hospitalization in this range of age.
- Rotavirus is the most frequent agent of AGE;
- norovirus is becoming the leading cause of medically attended AGE in countries with high rotavirus vaccine coverage.
- The most common bacterial agent is either Campylobacter or Salmonella depending on country.
*Intestinal infections are a major cause of nosocomial infection.
Etiology of age divided in age groups
*<a 1year: rotavirus, norovirus, adenovirus,
salmonella
*1-4 ani: rotavirus, norovirus, adenovirus,
salmonella, campylobacter, yersinia
*>5 years: campylobacter, salmonella,
rotavirus
Clinical Signs
*Diarrheic stool
*Vomitting
* Fever
*Abdominal pain
*Anorexia
* Seizures
* Tenesmus
* Erythema nodosum
Clinical signs of acute dehydration are to be added to the
clinical representation of acute diarrhea, as they severely
affect the disease
Clinical research has focused on the following:
- Fever (different definitions of absent, low, moderate, and high)
- Vomiting (absent, present, and different definitions of frequent)
- Onset (abrupt or more gradual)
- Stool frequency (different definitions of low, moderate, and high)
- Fecal mucus (present or not)
- Fecal blood (present or occult)
- Abdominal pain (present or not)
- Respiratory symptoms (rhinorrhea, cough)
- CNS involvement (irritability, apathy, seizures, or coma)
ATTENTION ASOCIATION DIARRHEA, OLIGURIA, EDEMA = suspicion
of hemolytic uremic syndrome
Risk factors that cause severe/persistent forms
of disease
- Clinical signs of severity: severe dehydration, repeated vomiting, persistent/high fever
*Age < 6 months - Etiology: rotavirus, norovirus, astrovirus, E Coli enteropatogen
- Socio-economic conditions
*Artificial nutrition - Community: prekindergarden, kindergarden
*Immunodeficiency
Are there any clinical signs that could lead to
the etiology?
*Fever > 40 ̊C, blood in the stool, abdominal
pain, irritability, seizures, coma = suggestive
for bacterial etiology
*Signs of vomiting and respiratory symptoms =
suggestive for viral etiology
Is a child with diarrhea dehydrated?
- The degree of dehydration is essential for the
therapeutic approach!
(expressed in loss weight)
*Minimal dehydration : <3% (Child) (5%) (Infant)
*Mild to moderate dehydration : 3-9% (6-10%) - Severe dehydration> 9% (10%)
When are electrolytes /astrup
needed?
*In cases of moderate and severe dehydration
*In case of parenteral rehydration
*Hypovolemic shock
*Neurological abnormalities (lethargy, seizures)
*Incoercible vomiting
When should one go to the doctor?
*Diarrhea: ≥ 8 episodes/day
* Persistent vomiting
*Infants < 2 months
* Severe underlying disease (diabetes mellitus or renal failure)
* Family reported sign of severe dehydration
When is hospitalization recommended?
- Shock
- Severe dehydration
- Somnolence, seizures, etc
- Persistent /bilious vomiting
- Lack of response to oral rehydration
- Social/family causes
- Suspected of surgical disease causes
Microbiological investigations
- Stool samples (Coprocultures)
*Microscopic examination of faecal samples (evaluation
of the number of leukocytes ) - Stool antigen (Rotavirus, Campylobacter etc)
*Verotoxina (shiga-like toxin) - EHEC O157:H7
(suspicion of hemolytic uremic syndrome)