Upper digestive system: Chapter 24 microbiology

Signs and symptoms of Dental caries (tooth decay)

-Usually already advanced before symptoms develop

-discoloration, roughness, tooth may break

-severe throbbing pain of toothache

Causative agent of Dental caries (tooth decay)

Streptococcus mutans (gram positive, live only on teeth, thrive in acidic conditions)

Streptococcus mutans is gram positive or gram negative ?

Gram positive

Dental Caries pathogenesis

-Results from acids produced by bacteria growing on the tooth

-Split sucrose into glucose and fructose

-S. Mutans, have a sucrose rich diet

-Lactic acid forms (what erodes enamel)

-Biofilm forms to protect bacteria

-Plaque → tartar formation

Dental Caries epidemiology

Worldwide, peaks during teen years

Dental Caries treatment and prevention

-Drill out cavity and replace with filling

-Restrict dietary sucrose

-Brushing and flossing

Periodontal disease signs and symptoms

-Gingivitis: gums are tender and bleed easily

-Chronc periodontitis: bad breath, red shiny gums that bleed easily, tooth lost

Periodontal disease bacteria and whether they are gram negative or gram positive

-Mostly gram negative anaerobes

-Porphyromonas

-Treponema

-Tannerella

-Prevotella

Periodontal disease pathogenesis

-Plaque and tartar accumulate

-Bacterial products cause and inflammatory response

-Tissue degrading enzymes are released by microbes

-Tissues detect LPS endotoxin, releases cytokines

Periodontal disease epidemiology

Mostly after 65, smokers, immunodeficiency

Periodontal disease treatment and prevention

Cleaning, minor surgery, flossing and brushing, antibiotics

Acute necrotizing gingivitis signs, causative agent, pathogenesis, epidemiology, treatment and prevention

-Signs and symptoms: Bleeding painful gums, some necrotic lesions, ulcerated

-Causitive agent: Heavy growth of anaerobes at gum line

-Pathogenesis: Plaque present with large numbers of spirochetes, meth lowers salvia production

-Epidemiology: Any age with poor oral hygiene

-Treatment and prevention: Antibiotics, removing plaque and tartar, daily brushing and flossing

Helicobacter pylori gastritis signs and symptoms

-Asymtomatic

-Belching, loss of appetite, nausea and vomitting

Helicobacter pylori gastritis causative agent and is it gram + or gram -

Gram negative helicobacter pylori

Helicobacter pylori gastritis pathogenesis

-Survives acidic environment of stomach

-produces urease, converts urea in gastric juices into ammonia, pH goes up

-VacA damages mitochondria and induces apoptosis

-CagA in strains with higher incidence of cancer

-Decreased mucus production

-90% of people with stomach cancer has this bacteria

H. Pylori epidemiology

-35% of adults in U.S infected, 80% over 75

-Transmitted fecal oral route

Treatment for H.Pylori

Antibiotics

Oral herpes pathogenesis

-Virus multiplies in epithelium

-Viral DNA can persist in nerve cells in latent form

Oral herpes simplex: Causitive agent, epidemiology, treatment and prevention

-Causitive agent: Herpes simplex virus (Double stranded DNA)

-2 types (HSV1 and HSV2)

-Epidemiology: Affects up to 90% of some populations

-transmitted by close contact

-can infect any body tissue

-Treatment and prevention: Meds like acyclovir, sunscreen

Mumps pathogenesis

-Virus inhaled by salvia droplets

-virus replicates in upper respiratory tract

-virus also replicates in salivary glands

-swelling can also impair blood supply to testicular tissue

Mumps Causitive agent, epidemiology, signs and symptoms, treatment and prevention

Signs and Symptoms: Onset by fever, loss of appetite, headache, swelling of salvary glands, spasm of muscles

Causative agent: mumps virus (single stranded RNA)

Epidemiology: Humans only host, virus spread from asymptomatic infections

Treatment and prevention: no effective treatment, attenuated vaccine (MMR vaccine)