• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/100

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

100 Cards in this Set

  • Front
  • Back
What is the target of the alpha- hemolysins produced by the Enterobacteriaceae?
More effective on lymphocytes.
What is the function of the beta hemolysins produced by the Enterobacteriaceae?
They are cell bound and inhibit phagocytosis and neutrophil chemotaxis.
What do the type III secretion systems of the Enterobacteriaceae do?
Target virulence factors to the cytoplasm of the host cell.
What is ETEC?
Enterotoxigenic E. coli - Traveler's diarrhea.
What are the specific virulence factors of enterotoxigenic E. coli?
ST - a heat stable toxin. Increases fluid excretion by mucosal cells in the small intestine.
LT - heat labile toxin. Virtually identical to cholera toxin.
What is EPEC?
Enteropathogenic E. coli - causes childhood diarrhea.
What is the specific virulence factor of enteropathogenic E. coli (EPEC)?
A shiga-like toxin.
What type of E. coli is responsible for childhood diarrhea of long duration?
EaggEC - Enteroaggregative E. coli
Which type of E. coli produces a severe dysentery-like illness?
EIEC - enteroinvasive E. coli.
Which type of E. coli is responsible for hemorrhagic colitis in children?
EHEC - enterohemorrhagic E. coli
Which strain of E. coli is associated with eating under cooked meat?
E. coli 0157:H7 - an EHEC type E. coli
Besides gastrointestinal infections, what other infections can be caused by E. coli?
Urinary tract infections by strains that make P fimbriae.
Neonatal meningitis by strains that produce the K1 capsular polysaccharide.
What type of illness is caused by Shigella spp.?
Diarrheal illness, associated with toxemia, systemic symptoms with blood and mucus in the stool.
What are the specific virulence factors of Shigella spp.?
Invasins: allow penetration of mucosal epithelial cells.
Shiga toxin: inhibits protein synthesis in target cells.
Type III secretion system.
What is the most common source of salmonellosis?
Contaminated water or food (especially poultry).
What is the most common form of Salmonella infection?
Gastroenteritis.
What type of Salmonella infection can cause severe and life-threatening disease?
Typhoid fever.
What is the pathogenesis of Salmonella infection?
Organisms multiply in small intestine. Adhere to the jejunum and invade epithelial cells.
Transport of organisms to lymph nodes. Ingestion of organisms by phagocytes with multiplication of the organism intracellularly.
Organisms make their way into the bloodstream and seed the RES.
What are the virulence traits of Salmonella?
Invasins : aid in penetration of epithelial cells.
Endotoxin.
Resistance to intracellular killing.
Vi antigen - inhibits phagocytosis, inhibits serum bacteriocidal activity. Type III secretion.
Carrier state.
What type of infection is caused by Yersinia enterocolitica?
Enterocolitis.
Exudative pharnyngitis.
What is the reservoir for Yersinia spp.?
Domesticated animals.
What is the etiologic agent of the plague?
Yersinia pestis.
What are the Gram stain and morphologic characteristics of Campylobacter spp.?
Gram-negative comma-shaped (may be called "gull winged")
How is man infected with Campylobacter jejuni?
Consumption of contaminated food and water.
What is the most prevalent food-borne illness in the USA?
Campylobacter jejuni
What types of extraintestinal infections can be caused by Campylobacter fetus?
Enteric. Meningitis. Septic arthritis. Salpingitis. Lung abscess.
What is the specific virulence factor of Campylobacter fetus?
S layer of the organism blocks complement and killing by serum.
What is the etiologic agent of peptic ulcer caused by a bacterium?
Helicobacter pylori.
What is the etiologic agent of cholera?
Vibrio cholerae.
What are the clinical findings in patients with cholera?
High volumes of watery diarrhea. Vomiting.
Fluid and electrolyte imbalance leading to dehydration.
How does man become infected with Vibrio cholerae?
From contaminated water.
What are the virulence factors of Vibrio cholerae?
Cholera toxin - causes fluid and electrolyte accumulation in the lumen of the gut.
What Gram-negative organism causes primary lobar pneumonia with a propensity for abscess formation in the lungs of immunocompromised individuals in a hospital setting?
Klebsiella pneumoniae
What is the most important treatment for all diarrheal diseases?
Fluid and electrolyte replacement.
What is the most important preventative measure for gastrointestinal diseases?
Safe water and food supplies.
How can typhoid fever be prevented in those traveling to areas with a high incidence of disease?
A vaccine is available that provides 2-5 years protection.
What is the natural habitat of Pseudomonas spp.?
Moist environments - soil, water, plants
How are Pseudomonas infections usually transmitted?
Via water.
What are the Gram stain and morphological characteristics of Pseudomonas spp.?
Gram-negative rods.
What is the leading cause of death in burn patients?
Pseudomonas infection.
What is the primary cause of death in cystic fibrosis patients?
Burkholderia cepacia infection.
Why is Pseudomonas infection a concern in the dental clinic?
The organism can be spread by aerosols generated by handpieces and contaminated water lines to handpieces.
What types of infections are caused by Pseudomonas aeruginosa?
Respiratory
Bacteremia
CNS infections
Ear infections
Eye infections
Bone and joint infections
Urinary tract infections
Gastrointestinal infections
Skin and soft tissue infections
How does algenate (the capsule) enhance the pathogenic potential of Pseudomonas?
Binding to tissues.
Anti-phagocytic.
Inhibits aminoglycoside antibiotics.
Besides its capsule what are some other virulence factors of Pseudomonas?
Pili.
Proteases. Cytotoxin. Hemolytic factors. Exotoxin A. Exotoxin S. Pyocyanin
What is typical of antimicrobic treatment of Pseudomonas and Burkholderia?
It must be aggressive, commonly using combinations of antibiotics that are synergistic.
What is the best way to prevent Pseudomonas and Burkholderia infections?
Rigorous cleanliness with attention paid to infection control practices.
What is the etiologic agent of gonorrhea?
Neisseria gonorrhoeae
What are the Gram staining and morphological characteristics of Neisseria?
Gram-negative diplococci (kidney bean shaped).
What types of growth requirements are needed by the pathogenic Neisseria spp.?
Enriched media needed.
What Neisseria species causes meningitis?
Neisseria meningitidis
In what age group do most of infections with Neisseria gonorrhoeae occur?
20 to 24 years of age.
Does immunity develop after infection with N. gonorrhoeae?
No.
What percent of women will develop gonorrhea after one sexual encounter with an infected male?
50%
What percent of men will develop gonorrhea after one sexual encounter with an infected female?
20%
What severe consequences can happen to women subsequent to having gonorrhea?
Pelvic inflammatory disease. Ectopic pregnancy.
Infertility.
What infection of children is considered to be an indication of child abuse?
Neisseria gonorrhoeae
In what age group does most of meningitis due to Neisseria meningitidis occur?
Children - 6 months to 4 years.
A second peak occurs at 18 years of age.
What are the most severe consequences of Neisseria meningitidis?
A high case fatality ratio in the USA. An epidemic killer in developing countries.
Why is an understanding of Neisseria infections important to the dentist?
These organisms can infect oropharyngeal mucosal surfaces. Proper practices are needed to protect the dentist and patient.
What are the risks of production of aerosols containing Neisseria to the dentist?
Infection of the conjunctiva leading to severe conjunctivitis, corneal ulceration, abscesses and potentially blindness.
What does gonococcal pharyngitis look like?
Patchy edema and erythema of the tonsilar pillars and uvula with discrete vesicles with exudate.
What types of infections can occur due to Neisseria gonorrhoeae?
Uncomplicated genital mucosal infection.
Pharynx infection.
Ophthalmia neonatorum - due to contamination at birth.
Are complications due to Neisseria gonorrhoeae common in the male?
No.
What are the complications associated with Neisseria gonorrhoeae in the female?
Disseminated gonococcal infection. Pelvic inflammatory disease and endocervical gonorrhea.
What part of the Neisseria gonorrhoeae organism is responsible for producing inflammation?
Endotoxin.
Peptidoglycan fragments.
How does Neisseria gonorrhoeae avoid the immune system?
lgA1 protease
Molecular mimicry - similarity to human antigens makes this organism have weak antigens.
Serum resistance - resistant to killing effects of complement.
Blocking antibody - these don't bind complement.
Phase and antigen variation.
How do you diagnose N. gonorrhoeae infection?
Culture is most reliable.
Antibiotic resistance is common among strains of N. gonorrhoeae.
The correct answer is: True
How do you prevent infection with N. gonorrhoeae?
Abstinence.
Use of condoms Tracking contacts.
How is Neisseria meningitidis spread?
Aerosols.
What types of infection are caused by Neisseria meningitidis?
Bacteremia.
Meningitis.
Meningoencephalitis.
Why is Neisseria meningitidis infection so dangerous?
Can be fulminant with death occurring as soon as 12 hours after appearance of symptoms.
What are the sequelae of systemic meningococcal disease?
Neurological deficits.
Amputations due to damage and tissue necrosis.
What are the virulence traits of Neisseria meningitidis?
Endotoxin (LOS). Peptidoglycan fragments. lgA1 protease. Anti-phagocytic capsule. Phase variation. Molecular mimicry.
Does effective immunity develop subsequent to infection with Neisseria meningitidis?
Yes. Due to development of cross¬reactive antibodies with normal flora.
What age group is most susceptible to Neisseria meningitidis infection?
6 months to 4 years old.
What can be done to prevent Neisseria meningitidis infection?
Vaccine - not effective in young children. Contact tracing.
Isolate infected patients.
What are the Gram staining and morphological characteristics of Haemophilus species?
Gram-negative pleomorphic rods
What special growth requirements are needed by Haemophilus species?
X factor - heme V factor - NAD or NADP
What diseases are caused by Haemophilus influenzae?
Meningitis. Otitis media.
What diseases are caused by Haemophilus parainfluenzae?
Endocarditis
Where is Haemophilus aphrophilus found in the body?
In the oral cavity.
What diseases can Haemophilus aphrophilus cause?
Colonizer of dental plaque. Juvenile forms of periodontitis. Endocarditis.
Brain abscesses.
Spinal fluid infections.
Jaw infections.
Wound infections.
Where is Haemophilus paraphrophilus found?
Colonizes dental plaque and other sites.
What diseases can be caused by Haemophilus paraphrophilus?
Endocarditis. Brain abscess. Osteomyelitis.
What are the major consequences to patients due to colonization of the oral cavity with Haemophilus species?
Juvenile forms of periodontal disease. Dental procedures leading to endocarditis.
What is the most common infection due to Haemophilus influenzae?
Meningitis.
Which type of Haemophilus influenza causes most invasive disease?
Type b
What type of Haemophilus influenzae commonly causes otitis media?
Nonencapsulated, nontypeable H. influenzae
What is the best way to prevent type b, H. influenzae infections?
Vaccination
What is the best way to prevent infection with non-typeable H. influenzae?
No prophylactic measures are currently available.
What are the Gram staining and morphologic characteristics of the rickettsia?
Gram-negative coccobacilli.
What type of growth conditions do the Rickettsia require?
They are obligate intracellular parasites.
What is the etiologic agent of Rocky Mountain spotted fever?
Rickettsia rickettsii
How are most rickettsia infections spread to humans?
Bite of an arthropod or insect vector
What diseases are caused by Ehrlichia spp?
Human monocytotrophic ehrlichiosis - HME.
Human granulocytotrophic ehrlichiosis - HGE.
Why is there a potential for spreading rickettsial disease in the dental clinic?
The agents are found in the bloodstream and therefore could be spread in the clinic if proper infection control practices are not followed.
How do you control the spread or rickettsial diseases?
Control the ectoparasites.
What is the leading cause of community- acquired pneumonia?
Chlamydophila pneumoniae