Ch.9-10 Flashcards
What disease does the “mantoux” or “tine test” test for?
Tuberculosis
Is tuberculosis gram negative or positive?
Neither, it is “acid fast”
What is unique about mycobacterium tuberculosis cell wall?
Waxy lipids called “mycolic acids” make up half or more of the envelope. This waxy layer is resistant to gram staining.
Generally speaking, how long is the antibiotic treatment for tuberculosis?
6 months - 2 years
During the 18th & 19th centuries, what disease was the cause of 25% of all adult deaths?
Tuberculosis
What is the drug isoniazid used to treat?
Tuberculosis
What type of organism is diphtheria?
Bacteria
Is Diphtheria graham positive or negative?
Gram positive
What is the mechanism of action of diphtheria?
Inhibits the 80s ribosomes of the host (prevents host cell protein synthesis). Affects the heart and nervous system and can cause death.
Describe the characteristics of the pertussis bacterium?
Gram?
Shape/organization?
Pertussis:
Gram negative
Coccobacillus
Is streptococcus gram negative or positive?
Gram positive
What is the bacterium that causes scarlet fever?
Streptococcus pyogenes
What is unusual about the morphology of Bordatella pertussis?
It is a coccobaccilus?
What are the 2 systems used to classify streptococci?
Lancefield’s grouping
Hemolysis type
What is the name of the bacteria known as group B strep?
In what relatively new site is group B strep found today?
Which people group are at risk from which diseases from group B strep?
S. agalactiae
Found in human vaginal tract.
Newborns are at risk for septicemia and meningitis.
What hemolytic classification is viridians strep?
What color will viridians strep produce on blood agar?
What particular disease does viridians strep cause?
Alpha hemolytic
Greenish Tinge
Sub-acute endocarditis
What chemical component of the cell wall is used to differentiate streptococci?
Cell-wall associated carbohydrate
In reference to Streptococcus pneumoniae (also called pneumococcus)
a. How does the capsule relate to virulence?
b. How many times can an individual can acquire pneumococcal pneumonia?
c. What group of strep is it?
d. Hemolytic group?
A. Only encapsulated strains are virulent
B. An individual can acquire pneumococcal pneumonia 90 times because there are 90 serovars.
C. Group D strep
D. Alpha hemolytic
List 2 unusual characteristics about Mycoplasma pneumoniae bacterium.
Is it gram negative or gram positive?
- No cell wall (peptidoglycan layer)
- Membranes contain sterols
Gram Negative
What disease is caused by mycoplasma pneumoniae?
Describe how to diagnose the disease caused by mycoplasma pneumoniae.
Walking Pneumonia
Observe increasing titers of cold agglutinins that cause RBC agglutination at refrigerator temperatures.
What is the prophylactic treatment for someone who comes in contact with a meningitis patient?
Rifampin
What is the most common cause of meningitis?
Is this bacteria gram negative or positive?
Hemophilus influenzae
Gram negative
How are Chlamydia pneumoniae cultured?
Inside human cells as they are obligate intracellular pathogens.
List 2 characteristics of the influenza virus.
Enveloped capsid
RNA genome
Name the 2 important surface proteins of the influenza virus.
- neuraminidase
2. hemagglutinin
Why does influenza predispose patients to secondary infections in the lungs?
Influenza inhibits phagocytic activity in the lungs.
What causes rubeola? (7-day rash that starts at the core and spreads to extremities)
Measles
Measles has a distinctive rash of reddish patches with white salt-crystal-like centers. What are these spots called?
Koplik’s spots
What is another name for rubella?
German measles
Rubella is a fairly minor disease only causing minor rash lasting about 3 days. Why is vaccination important?
Newborns are at risk of “congenital rubella syndrome” which can have devastating effects.
Name the 2 vaccines used for poliovirus.
Salk Vaccine (dead) Sabin vaccine (live attenuated)
What is the principle cause for the common cold?
Rhinoviruses
What is the primary site of infection for adenoid viruses?
Upper respiratory tract.
What is:
- A mutational change in the hemagglutinin and neuraminidase genes?
- A complete hemagglutinin gene change?
- Antigenic drift
2. Antigenic shift
What drug is used to treat RSV?
ribavirin via respirator
What 2 tissue types are primarily infected by polio virus?
- Alimentary canal
2. Neurons in the spinal column
What is dysentery?
Bloody diarrhea
What organism causes typhoid fever?
Salmonella typhi
What type of fever is associated with typhoid fever?
Stepladder fever (up and down)
Describe the typical symptoms of a cholera patient.
“Rice water” diarrhea with massive electrolyte loss - up to 20 liters per day.
What is disease transmission from animal to human?
Zoonosis
What is the transmission mode of cholera?
- Untreated water
2. Fecal/oral
What notable differentiating symptom does shigellosis have compared to salmonellosis?
Bloody diarrhea with a raspberry jam stool.
What is EMB agar used for?
To culture coliforms to trace the occurrence of fecal contamination in water and other food sources.
Describe the etiology and symptoms of the following diseases:
- Infantile diarrhea
- Travelers diarrhea
- Cystitis and bacteriuria
- E.coli, fecal/oral, diarrhea
- E.coli, diarrhea
- E.coli, polyuria, dysuria
How long can carriers spread salmonella typhi (typhoid fever)?
A lifetime
What gastric symptom is H.pylori commonly associated with?
Ulcers
All hepatitis viruses contain RNA except one. Which one contains DNA?
Hepatitis B
How does hepatitis cause jaundice?
Damaged liver cells are unable to completely breakdown hemoglobin resulting in increased levels of bilirubin.
What treatment does someone exposed to HAV receive?
Hepatitis A immune globulin
List possible diseases caused by the coxsackie virus.
Gastroenteritis Aseptic meningitis Herpangina Pleurodynia Myocarditis
List 3 Protozoa that cause intestinal tract infections.
Giardia
Entamoeba histolytica
Cryptosporidium parvum
What is the definitive host of a helminth?
The host in which the sexually mature form grows.
What are the 2 physiologic components of a tapeworm?
What is their function?
- Scolex (head with a sucker for attachment)
2. Proglottids (uterui that fill with eggs)
How is Taenia saginata acquired?
By eating tapeworm cysts in undercooked beef.
Regarding Legionaires disease:
Name of bacterium?
Gram?
Morphology?
Legionella pneumophila
Gram negative
Baccili
Regarding Chlamydia pneumoniae:
Gram?
Where does it replicate/reproduce?
Gram negative
Intracellular (obligate intracellular pathogen)
