Krista Blackwell Microbiology November 28, 2011

A disease that destroys red blood cells, causes anemia, and destroys renal function 1 Most common form of acute kidney failure in children 1 Caused when shiga-toxin producing E. coli release toxins into the blood stream and destroy red blood cells 1 Can be life threatening, however, most people recover completely 1

About E. coli Gram Negative Bacilli Family: enterobacteriaceae Do not form endospores Faculative Anaerobes Distributed worldwide 2 ronmental/life/cellular- microscopic/cell1.htm

 Major source of Foodborne and waterborne illness 3  Most harmful to children under the age of 5, the elderly, and people with compromised immune function 2  E. coli are capable of doubling their population in two hours 4  Incidence- Unknown 5  Causes about twenty thousand infections a year in the U.S. 4  About 79,420 cases of Enterotoxigenic E. coli occur each year in the U.S 5 March 27, 2011 CDC

Recent Outbreaks July 2011: Germany. Shiga- toxin producing E. coli July 2011: U.S. 6 confirmed cases of STEC O104:H4 June 2011: France. E. coli O104:H4 July 2011: All outbreaks were traced back to fenugreek seeds from Egypt 5

Organs and Organ Systems Affected Urinary System Digestive System w.mydiges tivehealth. com/

 E. coli lives naturally in the intestines of humans and animals 3  Most forms of E. coli are not harmful.  O157:H7  The GI tracts contains over 500 species of bacteria 6  The stomach and small intestine contain few microorganisms because of gastric acid, which suppresses bacteria populations 6  The colon contains mostly strict anaerobes and some aerobic and anaerobic bacteria 6  Bacteria populations in the large intestine are important for digestion of carbohydrates, lipids, and proteins 6 StomachJejunumIleumColon Viable bacteria per gram pH (6)

History  First emerged in 1982: Undercooked ground beef 3  E. coli 0157:H7- had at least 62 subtypes 4  Department of Agriculture 2  1991 and 1999: Waterborne 3 history/ winn-dixie-walmart-and-sams-club/

Subgroups of E. coli  Enterohemorrhagic E. coli (EHEC) O157:H7: Causes HUS and Hemorrhagic colitis 2  Shiga-toxin producing E. coli (SHEC)  Enterotoxigenic (ETEC): Releases a toxin into the large intestine resulting in overproduction of fluid and therefore diarrhea 5  Enteropathogenic (EPEC): The release of toxins results in bloods and watery diarrhea 2  Enteroinvasive (EIEC): Invade epithelial cells of the intestine which results in bacillary dysentery 2  Enteroaggregative (Eagg EC): Produces acute or chronic diarrhea with abdominal pain and vomiting ( 7 ichia-coli-and-its-outbreak-in.html

Through food or water that is contaminated with animal or human feces 5 Raw beef, chicken, or deer Raw milk Waterborne

 Commensalism: One organisms benefits while the other is unaffected 8  Saliva: Helps wash surfaces and dilute numbers of bacteria and prevent colonization and contain enzymes that prevent microbial growth 8  Gastric Juice: Has an acidity of about pH , which kills bacteria and toxins released by bacteria 8  Vomiting, defecation, and peristalsis: Remove microbes from the body 8  Urine: The flow of urine cleans the organs in the urinary system including the kidneys and urethra 8  White Blood Cells/Leukocytes: Some perform phagocytosis and others force the target cell to undergo apoptosis or cytolysis 8  Fever: Increases the speed of the host’s reactions to help repair tissues and increase the production of T cells 8

1.Portal of Entry: Enter into gastrointestinal tract through mouth (Mucous Membrane) 8 2.Attachment to Host Cell: Adhesions on fibriae 8 3.Penetration of Host Cell: Enter by endocytosis can also induce host cells to engulf them, this is similar to phagocytosis 8 4.Damage to Host Cell: Multiplies within the host cell and can leave through reverse phagocytosis. Damages the host cell because the E. coli uses up the cell’s nutrients and waste products accumulate 8 5.Portal of Exit: Exit through Gastrointestinal tract (Mucous Membrane) – from book 8

 Shiga Toxin-producing E. coli (SHEC) also known as verocytotoxigenic E. coli or enterohemorrhagic E. coli (EHEC) 5  Type of protein toxin 9  After entering the cell, inhibit protein synthesis by cleaving the RNA of the 60S ribosome 9  Shiga producing E. coli cause about 100,000 illnesses, 3,000 hospitilizations, and 90 deaths per year in the U.S 6 m/2011/06/ecoli-outbreak- in-france.html

 It usually takes about 2-4 days for symptoms such as diarrhea and vomiting to occur, however, it can sometimes take as long as 8 days for symptoms to appear 3  About 2 weeks after the onset of diarrhea, the symptoms for HUS appear 10  Pale, tired, unexplained bruises, bleeding from the nose or mouth, bloody urine, swelling of the face, hands, and body 1  Only about 2- 7% of O157:H7 infections result in HUS 10

Observation of Symptoms Stool and Blood Cultures 1 Gram Staining Increase fluid intake or intravenous fluid 11 Blood transfusion 1 Dialysis 1 Kidney Transplant 1 Medication from a type of drug called angiotensin-converting enzyme (ACE) 1 Diagnoses of HUS Treatment

 Avoid Raw Milk  Make sure meat is cooked thoroughly (Above 160°F)  Avoid cross contamination of raw meet and other foods  Wash hands

References