Diphtheria Review extra credit Flashcards
1. Know the following characteristics about Corynebacterium diphtheriae: Genus and species name Gram reaction Cell shape Disease name Transmission Virulence factors Clinical symptoms of disease Treatment
Genus name: Corynebacterium
species name: diphtheriae
Gram reaction: +
Cell shape: bacillus
Disease name: Diphtheria
Transmission: Air droplets (direct person to person)
Fomites (indirect): Diphtheria bacteria can live on fomite surface for minimum of 7 days and documented to live on some surfaces for 6 months
Virulence factors: Powerful exotoxin:
Interferes with protein synthesis in certain tissues
Transported through body via blood
Can stop heart function, damage nerve tissue, paralysis of muscle
Clinical symptoms of disease: Sore throat, fever, fatigue
Pseudomembrane forms on tonsils, tongue surface, pharynx, eventually can block air passage to lungs (by covering glottis opening to trachea)
(NOTE: Pseudo means false; therefore, a pseudomembrane is not true tissue but grows on tissue surfaces that are infected)
Exotoxin causes extreme swelling of throat tissue resulting in “bull’s neck”(Local affect)
Exotoxin enters blood damaging heart, nerves and kidneys initiating cell death (Systemic affect: spreads to internal organs via blood)
Treatment: Antibiotics: kill bacteria (Must kill bacteria to stop exotoxin production)
Antibiotics taken for 14 days/ Patient usually not contagious after 48 hours on antibiotics
Antitoxins: neutralize exotoxin (anti-serum ; Passive Artificial Acquired Immunity)
Antitoxins neutralize exotoxin in circulation but do NOT neutralize exotoxin adhered to tissue
(NOTE: Antitoxin is only available from the CDC in the USA)
- Be able to translate the organism’s genus and species name into the English language.
Corynebacterium means: club shape bacteria in reference to the
club shaped bacteria cells produced along with the normal thin bacillus cells
Diphtheria means: “leather-like” membrane in reference to the pseudomembrane produced during the course of the infection
- What is the cell shape and gram reaction of Corynebacterium diphtheria?
Gram +
bacillus shape
clubshaped
- Why does the bacteria cell stain irregular?
Presence of metachromatic granules(cause cell to stain irregular)
- What is unique about the shape and staining properties of Diphtheria bacteria?
Some cells enlarge and are club-shape (enlarged at one end and tapered at other end)
- Disease caused by Corynebacterium diphtheriae:
Diphtheria
- How is Corynebacterium diphtheriae transmitted direct person to person?
Air droplets
indirect contact on fomites
- Is Diphtheria considered to be a contagious disease?
Yes Very!!!
- Approximately how long can Corynebacterium survive on fomite surfaces?
Diphtheria bacteria can live on fomite surface for minimum of 7 days and documented to live on some surfaces for 6 months
- What is the virulence factor for the virulent strains of Corynebacterium diphtheria?
Powerful exotoxin:
Interferes with protein synthesis in certain tissues
Transported through body via blood
Can stop heart function, damage nerve tissue, paralysis of muscle
- What is the genetic source of the diphtheria toxin?
1
- What is a prophage?
virus
- Can the diphtheria toxin have both a local and systemic effect?
yes it can
- What are the clinical symptoms for diphtheria?
Sore throat, fever, fatigue
Pseudomembrane forms on tonsils, tongue surface, pharynx, eventually can block air passage to lungs (by covering glottis opening to trachea)
(NOTE: Pseudo means false; therefore, a pseudomembrane is not true tissue but grows on tissue surfaces that are infected)
Exotoxin causes extreme swelling of throat tissue resulting in “bull’s neck”(Local affect)
Exotoxin enters blood damaging heart, nerves and kidneys initiating cell death (Systemic affect: spreads to internal organs via blood)
- Define Pseudomembrane:
Pseudo means false; therefore, a pseudomembrane is not true tissue but grows on tissue surfaces that are infected
Pseudomembrane Characteristics
Grayish white
Composed of mucus, WBC, dead tissue cells, bacteria, exotoxin
- Is it possible for the pseudomembrane to obstruct the air passage way to the lower respiratory tract?
yes
- What is meant by “bull’s neck” and what causes it?
Exotoxin causes extreme swelling of throat tissue resulting in “bull’s neck”(Local affect)
- Why does treatment for diphtheria have to be two-fold and what does that mean?
Antibiotics: kill bacteria (Must kill bacteria to stop exotoxin production)
Antibiotics taken for 14 days/ Patient usually not contagious after 48 hours on antibiotics
Antitoxins: neutralize exotoxin (anti-serum ; Passive Artificial Acquired Immunity)
Antitoxins neutralize exotoxin in circulation but do NOT neutralize exotoxin adhered to tissue
(NOTE: Antitoxin is only available from the CDC in the USA)
- How long does a patient have to be on antibiotic therapy before they are rendered non-contagious?
Patient usually not contagious after 48 hours on antibiotics
- Why does the treatment of diphtheria typically require an antiserum?
1
- In the United States, what organization has the only available supply of antiserum?
CDC
- What is the CDC?
Centers for Disease Control and Prevention
- What category of acquired immunity is being applied in treatment with diphtheria antiserum?
Passive Artificial Acquired Immunity
- Does antitoxin = antiserum?
yes
- What does the antiserum contain that neutralizes diphtheria toxin?
1
- Can the antiserum neutralize diphtheria toxin already associated with tissue?
Antitoxins neutralize exotoxin in circulation but do NOT neutralize exotoxin adhered to tissue
- What is Diphtheria toxoid and how is it used?
lost toxicity (does not cause disease)
retains antigenicity (stimulates immunity because it is seen as foreign)
Adult form: Td (given every 10 years) and Tdap (given once between 11 – 64 yrs) [Look at your shot records to see if you have received the Tdap 1 time in place of Td for one of your booster shots]- What does toxoid mean?
non living part of the toxin used in vaccines to help your body to create their own antibodies
- What diseases does DTaP or Tdap vaccinate against?
D = Diphtheria (toxoid) T = Tetanus (toxoid) aP = (acellular) Pertussis
- What diseases does the Td vaccine vaccinate against?
Td vaccinates against 2 diseases: Tetanus and diphtheria
- Which form of the diphtheria vaccine is used in children, how many dosages are given, and at what age?
Children Form (5 doses): DTaP
2, 4, 6mths, 15 – 18mths, 4 – 6 years
(At ages 11 – 12 years, the booster shot is Tdap)
- Which form of the diphtheria vaccine is used in teens and adults and how often is the vaccine administered?
Td vaccinates against 2 diseases: Tetanus and diphtheria
Given to adults every 10 years
Tdap should be given only once in place of the Td vaccine between ages 11 - 64
- How often is the Tdap vaccine administered?
Tdap (given once between 11 – 64 yrs)
- What is the difference between the DTaP and the Tdap form of the vaccine?
Tdap has reduced dosages of diptheria and pertussis portion of vaccine compared to the DTaP
- Is Diphtheria a rare or common occurrence in the United States?
In the USA – very rare because of a successful vaccine program
but Vaccine program deteriorated when Soviet Union dissolved which led to 125,000 cases by 1995 in Eastern Europe mostly in children (NOTE: a rise of diphtheria could happen anywhere if vaccine administration is disrupted)
- What is the danger in any interruption of the diphtheria vaccine in the general population?
a rise of diphtheria could happen anywhere if vaccine administration is disrupted)
