Acute Infectious Diarrhea
An overview
By
Professor Dr Intekhab Alam
Faculty of Medicine
Khyber Medical University
PGMI, Lady Reading Hospital, Peshawar.
Introduction
Food poisoning (Acute Infectious Diarrhea) denotes gastrointestinal diseases caused
by micro-organism transmitted in food or by microbial toxins preformed in the
food.
Worldwide impact of food poisoning is great, responsible for
increasing childhood mortality and their physical and mental growth
retardation.
The commonest bacterial pathogens responsible for bacterial
gastroenteritis in the world are Enterobacteriaceae (E.coli,
Salmonella and Shigella) in underdeveloped and Compylobacter in
the industrialized world.
Epidemiology of Acute Infectious Diarrhea
Etiologic Agent
%age
Comments
Enterotoxigenic Escherichia coli
15–50
Single most important agent, particularly in summertime in semitropical areas; percentage of
cases ranges from 15% in Asia to 50% in Latin America
Enteroaggregative E. coli
20–35
Emerging enteric pathogen of worldwide distribution
Shigella and enteroinvasive
E. coli
10–25
Major causes of fever and dysentery
Salmonella
5–10
Causes fever and dysentery
Campylobacter jejuni
3–15
More common in winter in semitropical areas; more common in Asia
Aeromonas
5
Important in Thailand
Plesiomonas
5
Related to tropical travel and seafood consumption
Vibrio cholerae
0–10
Most common in India and Asia; also common in Central and South America
Rotavirus and norovirus
10–40
Latin America, Asia, and Africa; norovirus associated with seafood ingestion on cruise ships
Entamoeba histolytica
5
Particularly important in Mexico and Thailand
Giardia lamblia
<2
Zoonotic reservoirs in northern United States; affects hikers and campers who drink from
freshwater streams; contaminates water supplies in Russia
Cryptosporidium
2
Affects travelers to Russia, Mexico, and Africa; causes large-scale urban outbreaks in United
States
Cyclospora
<1
Affects travelers to Nepal, Haiti, and Peru; contaminates water or food
Unknown
20
Illness improves with antibacterial therapy, implicating bacterial diarrhea
GI Pathogens and the pathogenesis of acute Diarrhea
Mechanism
Location
Illness
Stool Findings
Examples of Pathogens Involved
Non
inflammatory
(enterotoxin)
Proximal small bowel
Watery diarrhea No fecal leukocytes;
Inflammatory
(invasion or
cytotoxin)
Colon or distal small
bowel
Dysentery or
inflammatory
diarrhea
Fecal
polymorphonuclear
leukocytes;
substantial increase in
fecal lactoferrin
Shigella spp., Salmonella spp., Campylobacter
jejuni, enterohemorrhagic E. coli, enteroinvasive
E. coli, Yersinia enterocolitica, Vibrio
parahaemolyticus, Clostridium difficile, ?A.
hydrophila, ?P. shigelloides, Entamoeba
histolytica
Penetrating
Distal small bowel
Enteric fever
Fecal mononuclear
leukocytes
Salmonella typhi, Y. enterocolitica,
?Campylobacter fetus
Vibrio cholerae, enterotoxigenic Escherichia coli
mild or no increase in (LT and/or ST), enteroaggregative E. coli,
fecal lactoferrin
Clostridium perfringens, Bacillus cereus,
Staphylococcus aureus, Aeromonas hydrophila,
Plesiomonas shigelloides, rotavirus, norovirus,
enteric adenoviruses, Giardia lamblia,
Protozoa:
Cryptosporidium spp., Cyclospora spp.,
microsporidia and isospora.
Bacterial Food Poisoning
Incubation Period, Organism
Symptoms
Common Food Sources
Staphylococcus aureus
(1-6 hrs)
Nausea, vomiting, diarrhea
Poultry, potato or egg salad, mayonnaise,
cream pastries
B. cereus(Gm+ive saprophyte)
Nausea, vomiting, diarrhea
Fried rice
Clostridium perfringens
(8–16 hrs)
Abdominal cramps, diarrhea (vomiting
rare)
Beef, poultry, legumes, gravies
B. cereus (Gm+ive saprophyte)
Abdominal cramps, diarrhea (vomiting
rare)
Meats, vegetables, dried beans, cereals
Vibrio cholerae (>16 H)
Watery diarrhea
Shellfish
Enterotoxigenic Escherichia coli
Watery diarrhea
Salads, cheese, meats, water
Enterohemorrhagic E. coli
(EHEC), E.coli O157:H7
Bloody diarrhea
HUS in 15% of children <10 yrs.
Ground beef, roast beef, salami, raw
milk, raw vegetables, apple juice
Salmonella spp.
Inflammatory diarrhea
Beef, poultry, eggs, dairy products
Campylobacter jejuni
Inflammatory diarrhea
Poultry, raw milk
Shigella spp.
Dysentery
Potato or egg salad, lettuce, raw
vegetables
Vibrio parahaemolyticus
Dysentery
Mollusks, crustaceans
Management
Take history: recent fast food or dining in a restaurant.
onset, frequency, consistency of stools, colic,
tenemus, vomiting and fever.
Examine and assess: Conscious state, Hydration status,
postural drop, icterus and abdominal tenderness.
collect stool sample for physical examination and if
indicated send for C/S.
Secure two wide bored IV lines and send blood for
S.Electrolytesa and S. Creatinine and keep strict
intake-output record and commence IV hydration.
Pass CV line if pt is in shock and peripheral IV access
is difficult. Keep hourly BP/Pulse record.
reatment of Acute Infectious Diarrhea on the Basis of Clinical Features
inical syndrome
Suggested therapy
atery diarrhea (no blood in stool, no fever), 1 or 2
formed stools per day without distressing enteric
mptoms
Oral fluids (Pedialyte, ORS, or flavored mineral water) and saltine crackers
atery diarrhea (no blood in stool, no fever), 1 or 2
formed stools per day with distressing enteric
mptoms
Bismuth subsalicylate (for adults): 30 mL or 2 tablets (262 mg/tablet) every 30 min for 8 doses; or
loperamide: 4 mg initially followed by 2 mg after passage of each unformed stool, not to exceed 8
tablets (16 mg) per day (prescription dose) or 4 caplets (8 mg) per day (over-the-counter dose);
drugs can be taken for 2 days
atery diarrhea (no blood in stool, no distressing
dominal pain, no fever), >2 unformed stools per
y
Antibacterial drug plus (for adults) loperamidea (see dose above)
sentery (passage of bloody stools) or fever
7.8°C)
Antibacterial drug
miting, minimal diarrhea
Bismuth subsalicylate (for adults; see dose above)
arrhea in infants (<2 y old)
Fluids and electrolytes (Pedialyte, ORS); continue feeding, especially with breast milk; seek medic
attention for moderate dehydration, fever lasting >24 h, bloody stools, or diarrhea lasting more
than several days
arrhea in pregnant women
Fluids and electrolytes; can consider attapulgite, 3 g initially, with dose repeated after passage of
each unformed stool or every 2 h (whichever is earlier), for a total dosage of 9 g/d; seek medical
attention for persistent or severe symptoms
arrhea despite trimethoprim-sulfamethoxazole
ophylaxis
Fluoroquinolone—with loperamide (see dose above) if no fever and no blood in stool, alone in
cases of fever/dysentery
arrhea despite fluoroquinolone prophylaxis
Bismuth subsalicylate (see dose above) for mild to moderate disease; consult physician for
moderate to severe disease or if disease persists
Post-Diarrhea Complications of Acute Infectious Diarrheal Illness
Complication
Comments
Chronic diarrhea
Occurs in ~1% of travelers with acute diarrhea
Lactase deficiency
Small-bowel bacterial overgrowth
Protozoa account for ~⅓ of cases
Malabsorption syndromes
(tropical and celiac sprue)
Initial presentation or exacerbation of
inflammatory bowel disease (IBD)
May be precipitated by traveler's diarrhea
Irritable bowel syndrome (IBS)
Occurs in ~10% of travelers with traveler's
diarrhea
Reiter's syndrome (reactive arthritis)
Particularly likely after infection with invasive
organisms (Shigella, Salmonella, Campylobacter)
Hemolytic-uremic syndrome (hemolytic
anemia, thrombocytopenia, and renal failure)
Follows infection with Shiga toxin–producing
bacteria (Shigella dysenteriae type 1 and
enterohemorrhagic Escherichia coli)
Differential Diagnosis of Acute Diarrhea
1.
2.
3.
4.
5.
Food intolerance e.g. Lactose intolerance,
Inorganic agents like Sodium nitrite,
Organic substances like Mushrooms and shellfish,
Drugs e.g. Laxatives and Antibiotics,
Emotional stress.
finally
1. Infectious agents including Bacteria, Viruses and Protozoal
agents.
Prevention
1.
2.
3.
4.
5.
All agents responsible for food poisonings are transmitteed through oro-fecal
route.
First principal is personal hygiene and handwashing before handling food,
eating and attending the toilet provides 80-90% safety against the
transmission of these agents.
It is of paramount importance to wash the food with plenty of fresh and
clean water before consumption, especially the raw food consumption like
lettuce and salad.
Production of safe food rests on evidence based practical technologies and
management systems; HACCP (Hazard Analysis and Critical Control Points).
This system identifies the Hazards and the points in a process whwere and
when they can occur and decides which points are critical to control to
ensure consumers’ safety, e.g. Pasteurization of the milk in which critical
points are, a)Temperatures reeached during heating, b)its duration and c)to
prevent subsequent contamination
Good sanitation and sewerage system and safe water supply
Thank you
Questions?
or
comments