Chapter 22 Flashcards
Dental Plaque
-begins as biofilm
-bacteria undergo metabolism
-produce acids that can dissolve tooth enamel
dental caries
tooth decay
gingivitis
inflammation of the gums
periodontal disease
-advanced inflammation causing the gums to bleed and pull away from the teeth
-aggregatibacter actinomycetemocomitans and porphyromonas gingivalis
thrush
-white coating resembling cottage cheese
-caused by the yeast strain, candida albicans
-common in newborns and patiens taking antibiotics
osmotic diarrhea
-intestinal osmolarity is higher than internal of mucosal cells, causing water to leave the cells
-pathogens that prevent nutrient absorption can cause osmotic diarrhea
secretory diarrhea
-increased ion secretion causes electrolytes to leave, leading to imbalance and water leaving intestinal cells.
-Pathogens that cause ion secretion cause secretory diarrhea.
inflammatory diarrhea
-inflammatory cytokines damage mucosal cells and prevent absorption of nutrients and water. Build up of water.
-Shigella and Salmonella are common causes of inflammatory diarrhea
motility-related diarrhea
-food moves too quickly through the intestinal tract and nutrients are not absorbed.
-Often caused by enterotoxins and rotavirus
gastritis
inflammation of the stomach lining
gastroenteritis
inflammation along the gastrointestinal tract
enteritis
inflammation mainly of the small intestine
enterocolitis
inflammation of the colon and small intestine
colitis
inflammation of the colon
hepatitis
-inflammation of the liver
-infection, overconsumption of alcohol, toxic chemicals, autoimmune reactions
rotavirus
-fecal-oral route
-nonenveloped, segmented, dsRNA
-enterotoxin that causes hypermotility of the intestinal tract
-vaccine prevents severe disease
norovirus
-fecal-oral route
-nonenveloped, positive sense, ssRNA
-causes sudden onset of symptoms; can also cause fever, headache, and malaise
-outbreaks common on cruise ships
paramyxovirus
Single-stranded RNA virus
Highly infectious, self-limiting infection
Parotid glands
Shed in saliva
Spread via sneezing and coughing
Causes massive swelling of parotid glands and can cause harm if swelling of testes occurs
Vaccination has eliminated most cases
Helicobacter pylori
Gram-negative
Survives acidic nature
Urease
Symptoms
Dyspepsia, upper abdominal pain, bloating, belching, nausea
Treatment
Proton pump inhibitors
Antibiotics
Enterotoxigenic E. Coli (ETEC)
Produces labile toxin
Causes secretory, watery diarrhea
No animal reservoirs
enteroinvasive E. coli (EIEC)
causes bloody diarrhea similar to that caused by Shigella
Enterohemorrhagic E. Coli (EHEC)
Shiga toxin
Causes bloody diarrhea
In severe cases EHEC can lead to hemolytic uremia syndrome and thrombocytopenic purpura-clots in either kidneys or circulatory system (skin hemorrhages)
shigellosis
Bloody diarrhea
Also called bacillary dysentery
Similar pathogenesis to EIEC
No animal reservoir, but is transmitted between humans through fecal-oral route via food or water
Symptoms include
Abdominal cramping
Fever
Vomiting
Watery diarrhea
Salmonellosis
two major diseases are typhoid fever and enterocolitis
typhoid fever
No animal reservoir
Associated with food preparation
Intermittent fevers and diarrhea for 1‒3 weeks
Usually resolves after 3-4 weeks, but sometimes antibiotics
enterocolitis
Associated with animal contact
Short-term illness lasts 6‒48 hours-nausea, vomiting, diarrhea
Not treated with antibiotics unless septicemia
yersiniosis
Gastrointestinal disease caused by
Y. enterocolitica
Y. pseudotuberculosis
Gram-negative bacilli
Associated with wild and domestic animals
Transmitted through food or milk
Can grow at refrigerator temperatures
Causes general enteritis lasting up to 2 weeks
Fever, cramping, sometimes nausea and vomiting, diarrhea
Antibiotics not recommended
Campylobacter enterocolitis
Gram-negative, corkscrew shape
Number one cause of diarrhea worldwide
Transmitted through consumption of poorly handled or undercooked meat and unpasteurized milk
Immunocompromised patients can experience disseminated disease.
Pancreas, gallbladder, heart muscles, or peritoneum
Hydration therapy, no antibiotics unless severe
Rarely, infection causes an autoimmune disease called Guillain-Barré syndrome (nerve damage)
cholera
Vibrio cholerae
Gram-negative curved rod with a single flagellum
Transmitted via fecal-oral route
Contaminated water
“Rice water stools”
Noninvasive; therefore, does not cause fever or bloody stools
cholera toxin
secretory diarrhea-stimulates secretion of electrolyes
listeriosis
Listeria monocytogenes
Gram-positive, non-spore‒forming coccobacilli
Associated with animals and animal products
Especially unpasteurized dairy
Causes a mild gastroenteritis
Immunocompromised patients experience disseminated infection and severe septicemia
The bacteria lives inside macrophages to avoid detection by the immune system
antibiotic-associated colitis
Clostridium difficile (commonly called C. diff)
Gram-positive, endospore-forming
Chronic antibiotic
Nosocomial infection due to improper cleaning and disinfection coupled with vulnerable populations
Toxin production
Toxins A, B, and CDT
Treatment is often fecal bacterial transplant.
staphylococcus food poisoning
Staphylococcus aureus
Gram-positive, cocci
Symptoms are seen within 2‒6 hours upon ingestion
Toxin is heat stable
