Microbiology - Pathogens of the Digestive System

Pathogens of the Digestive System

Chapter 25

1. Diseases that enter via the digestive Tract

A. Gastroenteritis

i. Preformed Bacterial Toxins

ii. Noninvasive Bacteria

iii. Intracellular Invasion

B. Systemic or Neurological Infections

C. Oral Lesions

2. Bacteria of Diseases via. Preformed Bacterial Toxins

A. Staphylococcus aureus (pp. 711 - 712)

i. General Information (p. 318)

a. Carriers

b. Locations

c. Nosocomial Infections

ii. Diseases

a. Staphylococcal Food Poisoning

• Growth Factors

• Heat-stable Enterotoxin

• Symptoms

b. Prevention

B. Bacillus cereus (pp. 720 - 721)

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Microbiology - Pathogens of the Digestive System

i. General Information

a. Environment

b. Endospores

c. Disease Symptoms

d. Prevention

ii. Toxins

a. Heat-Labile

b. Heat-Stable

C. Clostridium botulinum (pp. 616 - 619)

i. General Information (p. 316)

a. Obligate anaerobe

b. Endospores

c. Exotoxin

• Types A, B, and E

• Heat Susceptibility

• Cases

* Europe

* United States

* Farm Animals

ii. Diseases

a. Botulism

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Microbiology - Pathogens of the Digestive System

• Flaccid Paralysis

b. Infant Botulism

c. Wound Botulism

ii. Therapy

a. Trivalent Antitoxin

b. Supportive Care

D. Clostridium perfringens (p. 720)

i. General Information

a. Toxin

b. Wound infections and food poisoning

• Contamination

• Gas Gangrene (P. 646)

* Ischemia Necrosis and Anaerobic

ii. Clostridium perfringens Gastroenteritis

a. Contamination

3. Bacterial Diseases of the Mouth

A. Streptococcus mutans (pp. 706 - 709) (see handout)

i. Etiology

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Microbiology - Pathogens of the Digestive System

a. Biofilm

• Dental Plaque

• Metabolic Pathways (see handout)

* Dextran (Glycocalyx)

* Lactic Acid

ii. Diseases (pp. 708 - 709)

a. Dental caries

b. Gingivitis

c. Periodontitis

4. Fungal Diseases via. Preformed Toxins

A. Aspergillus flavus (p. 443)

i. Disease

a. Mycotoxicosis

• Liver Damage

• Cirrhosis

• Liver Carcinoma

ii. Virulence Factor

a. Mycotoxin

• Aflatoxin

5. Non-invasive toxin producing Bacteria

A. Escherichia coli (p. 310; pp. 717 - 718)

i. E. coli Strains

a. Enterotoxigenic E. coli (ETEC)

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Microbiology - Pathogens of the Digestive System

• Colonizing Factors

* Fimbriae

• Toxins

* LT (Heat Labile Toxin)

* ST (Heat Stable Toxin)

b Enteroinvasive E. coli (EIEC)

• General Information

* Outbreaks

c. Enterohemorrhagic E. coli (EHEC)

• General Information

* Outbreaks

* Fimbrial Adhesion

* Two shiga like toxins

* Serotype: 0157:H7

• Hemolytic Uremic Syndrome

• Control

B. Vibrio cholerae (pp. 716 - 717)

i. General Characteristics

a. Bacteria

b. Epidemics

ii. Disease

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Microbiology - Pathogens of the Digestive System

a. Cholera

• Fecal-oral route

• Non-invasive

• Mortality

iii. Virulence Factors

a. Choleragen

iv. Control

a. Sanitation

b. Vaccine

v. Treatment

a. Antibiotics

b. Rehydration

C. Campylobacter jejuni (p. 718)

i. General Information

a. Reservior

b. Transmission

c. Disease: Campylobacteriosis (Campylobacter

Gastroenteritis)

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Microbiology - Pathogens of the Digestive System

D. Helicobacter pylori (pp. 718 - 720)

i. Stomach Review

ii. Mechanism of Disease

iii. Chemotherapy

6. Bacteria that Invade and Grow Intracellularly

A. Shigella sp. (p. 712)

i. General Information

a. Reservoir

b. Symptoms

c. Species

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Microbiology - Pathogens of the Digestive System

ii. Disease

a. Bacillary Dysentery (or Shigellosis)

b. Transmission

c. Invasiveness

e. Dysentery

iii. Virulence Factor

a. Shiga Toxin

b. Lysogenic Conversion

iv. Control

B. Enteroinvasive E. coli (p. 717)

i. Invasiveness

ii. Disease

iii. Lysogenic Conversion

C. Salmonella sp. (pp. 712 - 714)

i. General Information

a. Peritrichious flagella

b. Reservoir

ii. Pathogenesis of Salmonellosis

a. Transmission

• Cases

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Microbiology - Pathogens of the Digestive System

• Associations

• Eggs

b. Etiology

iii. Control

a. “Scramble or Gamble”

b. Industrial Issues

iv. Symptoms

D. Salmonella typhi (pp. 714 - 716)

i. General Information

a. Transmission

b. Acid resistant

ii. Typhoid Fever

a. Invasivemess

b. Gall Bladder

c. Symptoms

d. Chronic Carriers

• “Typhoid Mary”

e. Vaccine

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Microbiology - Pathogens of the Digestive System

E. Listeria monocytogenes (pp. 614 - 615)

i. General Information

• Transmision

• Source

• Growth

ii. Reservior

iii. Diseases

a. Listeriosis

b. Meningitis

c. Still birth

d. Carriers

F. Bacteroides fragilis

i. Diseases

a. Intraabdominal Abscesses

b. Lung Abscesses

c. Bacteroides Bacteremia

7. Protozoal Diseases of the Digestive Tract

A. Entamoeba histolytica (p. 348; 731 - 732)

i. General Information

ii. Disease

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Microbiology - Pathogens of the Digestive System

a. Amebic Dysentery (Amoebiasis)

b. Carriers

B. Naegleria fowlerii (p. 629)

i. Disease

a. Primary Amebic Meningoencephalitis

C. Balantidium coli (p. 354)

i. Disease

a. Balantidiasis

D. Giardia lamblia (p. 730)

i. Disease

a. Giardiases

E. Toxoplasma gondii (p 661 - 663)

i. Introduction

ii. Stages

a. Acute

b. Chronic

iii. Forms

iv. Life Cycle

v. Disease

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Microbiology - Pathogens of the Digestive System

a. Toxoplasmosis

• Congenital Toxoplasmosis

• Toxoplasma Encephalitis (TE)

iv. Treatment and Prevention

a. AIDS patients

• Acute Stage Therapy

• Maintenance Treatment

b. Immunocompromized Patients and Pregnant Women

c. Prevention

8. Parasitic (Multicellular Euchariotic) Diseases of the Digestive Tract

A. Taenia saginata (pp. 356 - 358; 732 - 733)

i. General Information

a. Definitive Host

b. Intermediate Host

ii. Life Cycle

iii. Disease

a. Symptoms

b. Psychological Distress

c. Control

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Microbiology - Pathogens of the Digestive System

B. Taenia solium (pp. 356 - 358; 732 - 733)

i. General Information

a. Definitive Host

b. Intermediate Host

i. Disease

a. Cysticercosis

C. Trichinella spiralis (pp. 736 - 737)

i. Life Cycle

ii. Disease

a. Trichinosis

D. Enterobius vermicularis (pp. 360; 734 - 735)

i. Disease

a. Pinworm

9. Enteric Viruses That Cause Disease

A. Polio

i. Disease

a. Poliomyletis (pp. 620 - 622)

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Microbiology - Pathogens of the Digestive System

ii. Vaccine

a. Salk vaccine

b. Sabin vaccine

• Disadvantages

iii. World Elimination of Polio

A. Hepatitis A Virus (HAV) (infectious hepatitis) (pp.721 - 723)

• General Information about Hepatitis

i. Statistics

ii. About the Virus

iii. Transmission

• Fecal Oral Route

• Shellfish

iv. Disease

v. Vaccine

vi. Prevention

B. Hepatitis B (Serum Hepatitis) (pp. 723 - 726)

i. About the Virus

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Microbiology - Pathogens of the Digestive System

ii. Incubation / Pathology

iii. Transmision

iv. Clinical Course

v. Therapy

C. Hepatitis C (p. 726)

i. General Information

a. The Virus - (non A, non B)

b. Development of Disease

c. Effected

d. Cause

e. Severity

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