Bio 205 Ch 25 - Microbial Diseases of the Digestive System

Flashcards about Microbial Diseases of the Digestive System

Fecal/oral route

The typical route of transmission for microbial diseases of the digestive system.

Dental Plaque

A biofilm on the surface of teeth where organisms ferment carbohydrates, creating lactic acid.

Lactic acid

Weakens enamel, leading to dental caries.

Streptococcus mutans

The most common cause of cavities because it produces dextran.

Tartar

Calcified deposits of plaque.

Periodontal Disease

Inflammation and degeneration of structures that support the teeth.

Gingivitis

Infection of the gingiva (gums).

Periodontitis

Chronic gingivitis where gums are inflamed and bleed easily.

Staphylococcal Food Poisoning

Caused by ingestion of S. aureus enterotoxins.

Shigellosis (bacterial dysentery)

Causative agent is a G- facultative anaerobe rod of the genus Shigella.

Salmonellosis (Gastroenteritis)

G-rod, facultative anaerobe, non-spore former; normal in the intestinal tracts of animals.

Typhoid Fever

Causative agent is Salmonella typhi; found only in human feces.

Cholera

Causative agent is Vibrio cholera, a G-, flagellated curved rod that produces exotoxin.

Traveler's Diarrhea

E. coli is most common cause

Peptic Ulcers

Causative agent is Helicobacter pylori, a spiral microaerophile.

C-dif

Causative agent is Clostridium difficile, a G+, spore forming obligate anaerobe rod that produces exotoxins.

Mumps

Targets the parotid glands; saliva or respiratory transmission.

HAV (Hepatitis A Virus)

Single stranded (SS) RNA virus without an envelope; food borne transmission; no chronic form.

HBV (Hepatitis B Virus)

Double stranded (DS) DNA virus with an envelope; not found in urine or feces but found in other body fluids.

HCV (Hepatitis C Virus)

SS RNA virus with envelope; often undetectable until chronic, then leads to liver cancer or cirrhosis.

HDV (Hepatitis D Virus)

SS RNA virus only found in those that already have HBV; increases the mortality rate of HBV patients.

HEV (Hepatitis E Virus)

SS RNA virus with an envelope; fecal/oral transmission; does not cause chronic liver disease.

Mycotoxins

Fungal toxins that cause blood diseases, nervous system disorders, kidney and liver damage, and cancer.

Giardiasis

Caused by a flagellated protozoan called Giardia intestinalis; attaches to the intestinal wall.

Cryptosporidiosis

Caused by Cryptosporidiosis parrum or C. hominis; creates a cholera-like diarrhea.

Amoebic Dysentery

Entamoeba histolytica is the causative agent; causes severe diarrhea containing RBCs.