BI of the GI Track

• Foodborne Disease can arise from either infection or intoxication
• – inflammation of the mucosal lining of the stomach

  Gastritis
• – inflammation of the small intestines

  Enteritis
• – inflammation of the colon (large intestines)

  Colitis
• – inflammation of the mucosal lining of the stomach and intestine

  Gastroenteritis
• – inflammation of the liver

  Hepatitis
• – low-volume, painful, bloody diarrhea

  Dysentery
• • a gram-positive aerobic rod or bacillus, mildly pathogenic, low virulence
  • an opportunist pathogen

  Bacillus cereus
• types of Bacillus cereus

  1. Emetic Type- associated with re-warmed fried rice
  2. Diarrheal type – associated with meat dishes, poultry, vegetables, sauces
• • causes food poisoning with the shortest incubation period of 30 minutes to 8 hrs., average of 2 hrs.
  • Enterotoxins produced when the organisms grows in food rich in carbohydrates and protein

  Staphylococcus aureus
• • Anaerobic gram-positive spore forming rod
  • Enterotoxin produced that causes food poisoning
  • Incubation period – 8-24 hrs

  Clostridium perfringens
• • Marine organism Curved Gram=negative coccobacillus
  • Produces enterotoxin, possess flagella and pili
  • common cause of bacterial gastroenteritis associated with seafoods

  Vibrio parahaemolyticus
• Gastroenteritis (Diarrhea)

  A) enterotoxin

  B) cytotoxin

  C) inflammation

  D) intense inflammation

  E) intestinal mucosa

  F) dysenteric

  
• • Non-invasive bacterial diarrhea
  • is a gram-negative, motile, encapsulated rod, that produces disease when it reaches the tissues outside of their normal flora sites

  Escherichia coli (E. coli)
• 5 Pathogenic groups of Escherichia coli (E. coli)

  1. Enterotoxigenic E. coli (ETEC)
  2. Enteropathogenic E. coli (EPEC)
  3. Enteroaggregative E. coli (EAEC)
  4. Enteroinvasive E. coli (EIEC)
  5. Enterohemorrhagic E. coli (EHEC)
• An E. Coli

  • “traveler’s diarrhea” or “turista”
  • intense and prolonged hypersecretion of water and chlorides and inhibits sodium re-absorption.
  • cause of diarrhea in infants

  Enterotoxigenic E. coli (ETEC)
• An E. Coli infection

  • associated with outbreaks of diarrhea in nurseries.
  • Dehydration, electrolyte imbalance and other complications may cause death.
  • Antibiotic therapy is necessary

  Enteropathogenic E. coli (EPEC)
• An E. Coli Infection

  • causes acute and chronic diarrhea and causes food-borne illness in industrialized countries

  Enteroaggregative E. coli (EAEC)
• An E. Coli infection

  • causes invasion of colonic mucosa, commonly in children and travelers
  • acute bloody diarrhea, malaise, headache, high fever, abdominal pain
  • Cause: UTI, meningitis in newborn

  Enteroinvasive E. coli (EIEC)
• An E. Coli infection

  • source from undercooked meat (hamburgers)
  • bloody diarrhea, vomiting, severe abdominal pain associated with hemorrhagic colitis

  Enterohemorrhagic E. coli (EHEC)
• • Non-invasive bacterial diarrhea
  • Comma-shaped, curved, motile rod with flagellum
  • Produces enterotoxin that stimulates prolonged hypersecretion of water and electrolytes

  Vibrio cholerae (El tor)
• • Non-invasive bacterial diarrhea
  • a toxin-producing organism that can produce invasive infection

  Clostridium perfringens
• • Invasive Bacterial Diarrhea
  • Gram-negative, encapsulated, motile rods
  • have three important antigen (flagella, capsule, cell wall)
  • Incubation period: 8-48 hrs.

  Salmonella spp.
• Clinical Findings of Salmonella spp.

  1. Enterocolitis– invasion of small and large intestine
  2. Typhoid or enteric fever– slow onset with fever, bradycardia and constipation
  3. Septicemia – occurs in patient with underlying disease (e.g. Sickle anemia or Cancer)
• • Invasive bacterial diarrhea
  • a Gram- negative, non motile, non encapsulated rods
  • Incubation period: 24-72 hrs.

  Shigella spp.
• Tuberculosis of the gastrointestinal tract

  1. Mycobacterium tuberculosis- transmitted through swallowed after being coughed up from a lung lesions
  2. Mycobacterium bovis– ingested in unpasteurized milk products
• • Anaerobic, gram-positive, spore forming rod
  • Most common Nosocomial cause of diarrhea
  • Organisms produces exotoxins that cause death of enterocytes

  Clostridium difficile
• Dental Caries (Tooth decay) Organisms

  Streptococcus mutans
• Dental caries is most commonly caused by the bacteria Streptococcus mutans and is associated with sucrose and lactic acid.
• Periodontal diseases are mixed infections caused by different groups of bacteria. The infection involve inflammation of the gums and the progressive destruction of the deeper tissues and alveolar bone.
• Oral thrush is most commonly caused by Candida albicans and is associated with a variety of predisposing factors like immunosuppression and intake of broad-spectrum antibiotics, among others.
• Mumps is a highly communicable infection characterized by an inflammation of the salivary glands.
• Helicobacter pylori produces urease which enables it to survive the acidity of the stomach. It is a common cause of gastritis, peptic ulcer, gastric carcinoma, and MALT lymphomas.
• The most common causes of hepatitis are viruses.
• Hepatitis A and B are acquired through the fecal-oral route while Hepatitis B, C, and D are acquired by sexual, parenteral, and transplacental transmission.
• Chronic liver disease can be due to alcoholism, chronic viral hepatitis (hepatitis B and C), autoimmune disorders, metabolic disorders, and drug toxicities.
• Non-A, non-B hepatitis refers to any form of hepatitis that does not fall under the categories of Hepatitis A or B.
• Hepatitis E is similar to Hepatitis A but has higher mortality rates especially during pregnancy.
• Cryptococcus neoformans is a fungus that grows on decaying vegetation or soil contaminated with bird droppings. It infects the lungs and spreads via bloodstream to other organs such as brain, skin, bone marrow, and eyes.
• Aspergillosis is a type of mycosis caused by Aspergillus fumigatus. It usually affects people who have weakened immune systems from diseases like HIV/AIDS, cancer, diabetes mellitus, organ transplant recipients, and those taking corticosteroids.