Respiratory Disease

Question 1

Respiratory Tract System

Answer 1

• most common entry point for infections
• upper tract- mouth nose, nasal cavity, sinuses, throat, epiglottis and larynx
• lower tract- trachea, bronchi, and bronchioles in the lungs
  
  • no normal flora, free of microbes

Question 2

common infections

Answer 2

• pharyngitis- sore throat
• laryngitis- S. pneumoniae, S. pyogenes, viruses
• Tonsillitis- same as above
• Sinusitis- S. pneumoniae, H. influenzae
• Epiglottis- H. influenczae type b; life threatening; fast moving

Question 3

streptococcal pharyngitis

Answer 3

• S. pyogenes
• Group A beta hemolytic strep
• Virulence factors
  
  • streptokinases- lyse fibrin clots (breakdown clots)
  • streptlusins- cytotoxic to tissue cells and lyse (break open RBC)
  • M protein- resist phagocytosis

Question 4

Streptococcus pharyngitis

Answer 4

• inflammation and fever
• ear infections are complication
• respiratory route
• indirect latex agglutination (test)
• should treat with antibiotics

Question 5

Diphtheria

Answer 5

• Corynrbacterium diptheriae
• was leading cause of death in children before vaccine, DPT
• vaccine is a toxoid
• most of the damage of this organism caused by exotoxin produced in lysogenized strains

Question 6

Diphtheria vs. Strep

Answer 6

Diphtheria- inflamed pharynx and tonsils marked by grayish pseudomembrane formed by the bacteria are characteristic signs of diphtheria

strep- white patches on throat

Question 7

mechanisms of of A-B toxin of Corynebacterium

Answer 7

• one of most potent exotoxins
  -toxin interferes with protein synthesis; damages kidneys, heart etc.
• antitoxins must be used with antibiotics
  -Pseudomembrane
  -sub-clinical infections
  respiratory route

herd immunity

Question 8

Whopping Cough

Answer 8

• Bordetella pertussis
• Gm neg, coccobacillus, capsule, destroys the ciliated cells of trachea
• Tracheal toxin- ciliated cells
• Pertussis toxin- systemic toxin
• highly contagious
• vaccine- reactions to whole cell vaccine
• respiratory route
• new vaccine is acellular and causes fewer reactions: DTaP –> aP is acellular pertussis

Question 9

Pneumonia

Answer 9

viral, bacterial and fungal

Question 10

Pneumococcal pneumoniae

Answer 10

• S. pneumoniae, Gm pos diplococci, capsule
• high fever, breathing difficulty and chest pain
• involves both bronchi and alveoli
• vaccine- purified

bacteria

Question 11

Mycoplasma pneumoniae

Answer 11

• no cell walls
• require growth factors to culture
• low fever, cough, head ache 3-6 weeks
• walking pneumonia
• primary atypical (not as severe)

Question 12

Influenza

Answer 12

• influenza virus; many serotypes
• chills, muscle aches
• US:
  
  • 5% to 20% gets the flu
  • more then 200,000 get hospitalized
  • 36,00 die

Question 13

Antigenic changes

Answer 13

• strains typed based on antigens
  
  • N= neuraminidase
  • H = hemagglutinin

Antigenic drift- gradual changes in the antigens on virus

Antigenic shift- major shift in antigens, could be from recombination in swine or change that allows bird blu to directly infect humans

Question 14

Proposed emergence of H1N1

Answer 14

• caused pandemic in 2009 (worldwide)
• 3 strains of influenza virus from different species
• recombination of flu genes in swine

Question 15

Swine Influenza

Answer 15

• emerging disease

Question 16

Vaccine

Answer 16

• multivalent vaccines
  
  • 3 strains that are prevalent in world
  • decide by summer
  • inactivated, dead , virus in injection
  • live, attenuated in FluMist
• Antiviral drugs
  
  • effective if started right away
  • milder case