22 - Respiratory System Infections

  1. 2 classes of respiratory system infections:
    • Upper - Head and neck, not life threatening
    • Lower - Chest, can be life threatening
  2. Where are upper respiratory bacteria usually found?
    • Nasal Cavity
    • Nasopharynx
    • Pharynx
  3. Symptoms - Difficulty Swallowing, Fever, Red throat with pus patches, Enlarged lymph nodes, Recovery 1 weekCausative
    Agent - Stretpococcus Pyogenes, Gram +, Coccus in Chains
    Pathogenesis - Wide variety of illness including Scarlet Fever and Quinsy
    Epidemiology - Respiratory droplets 2 - 5 ft, only humans, nasal more potent than pharyngeal, more common in winter or spring
    Prevention - No vaccine, adequate ventilation, Avoid crowds, Sore throat w/fever should be cultured
    Treatment - Penicillin or Erythromycin in 10 days
    Streptococcal Pharyngitis (Strep Throat)
  4. Symptoms - mild sore throat, slight fever, neck swelling
    Causative Agent - Corynebacterium diptheria, variably shaped, Gram +
    Pathogenesis - Exotoxin released into bloodstream, A chain attaches to host cell membrane, B chain becomes enzyme that inhibits protien synthesis
    Epidemiology - Inhalation, humans primary reservoirPrevention - immunization
    Treatment - Penicillin and Erythromycin, 1 in 10 die with treatment
  5. Symptoms - Increased tears and redness, swelling eyelids, large amounts
    of pus, sensitivity to bright light.
    Causative Agents - Haemophilus
    Influenza, Stretpococcus Pneumonia
    Pathogenesis - Airborne
    respiratory droplets
    Epidemiology - Common among school children,
    crowded environments
    Prevention - Handwashing, don't touch or rub
    Treatment - Antibacterial eyedrops or ointments
    Pink Eye
  6. Symptoms - Pain, pressure, tenderness over sinus cavaties, headache,
    severe malaise
    Causative Agents - Mycoplasma Pneumonia, Streptococcus
    Pyogenes, Staphylococcus Aureus
    Pathogenesis - Infection of
    nasopharynx, spreads up towards sinuses
    Epidemiology - Adults and
    older children due to move developed sinuses
    Prevention - None
    - Treat symptoms
  7. Symptoms - Extreme ear pain, mild fever, vomitting, rupture of ear drum
    Agent - Mycoplasma pneumoniae, Streptococcus pyogenes, Staphlococcus
    Pathogenesis - Infection moves to middle ear from from nasal
    chamber, ear drum often bursts bringing immediate pain relief
    - Common before age 5
    Prevention - Flu vaccine
    Treatment -
    Otitis Media
  8. Symptoms - Scratchy, mild sore throat, runny nose, cough and hoarseness,
    NO FEVER, symptoms disappear in about a week
    Causative Agent -
    usually Rhinovirus, single stranded RNA genome
    Pathogenesis - Virus
    attaches in respiratory system, causing inflammation, which causes runny
    nose, sneezing
    Epidemiology - Humans only source, close contact with
    infected person during 1st 2 - 3 days
    Prevention - No vaccine
    - OTC meds may prolong symptoms instead of making them better. Let it
    run its course
    Common Cold
  9. Symptoms - Runny nose, fever, Sore throat with pus on pharynx and
    tonsils, enlarged/tender lymph nodes
    Causative agent - Adenovirus,
    non enveloped, double stranded DNA genome
    Pathogenesis - Infects
    epithelial cells, adenovirus 4 causes sore throat and lymphnode
    enlargement, Adenovirus 8 causes eye infection
    Epidemiology - Human
    only carriers, Sporadic outbreaks in winter and spring
    Prevention -
    No vaccine
    Treatment - No treatment
    Adenoviral Pharyngitis
  10. Symptoms - Cough, Chest pain, Fever, Sputum production, pale, pasty skin
    Causative agent - Streptococcus Pneumoniae, Gram +, thick polysaccharide capsule
    Pathogenesis - Breathed in, causes lung problems, poisoning of blood, can effect heart and cause meningitis
    Epidemiology - 30% of healthy persons carry strain in their throat
    Prevention - Vaccine gives immunity to 23 strains, Conjugate vaccine against 7 types available for infants
    Treatment- Penicillin and Erythormycin if given early
    Pneumococcal Pneumonia
  11. Symptoms - Gradual onset, First fever, headache, muscle pain, fatigue,
    Later dry coug and mucoid sputum
    Causative Agent - Mycoplasma
    pneumoniae, small, deformed, lacking cell wall
    Pathogenesis - Small
    infecting dose, attaches to receptors on epithelium, inflammation causes
    thinkening of bronchial and alveoloar walls causing difficulty
    Epidemiology - Aerosolized droplets from respiratory
    secretions, accounts for 1/5th of bacterial pneumonias
    Prevention -
    No practical prevention
    Treatment - Antibiotics, penecillin is ineffectual
    Mycoplasmal Pneumonia
  12. Symptoms - Runny nose, uncontrolable coughing
    Causative agent -
    Bordetella pertussis, small, aerobic, gram negative bacillus
    - Enters respiratory tract, attaches to ciliated cells, causing cough
    - Resperatory droplets, most infectious during runny nose period,
    common in infants
    Prevention - Vaccination of infants
    Treatment -
    Erythromycin if given early
    Whooping Cough
  13. Symptoms - Slight fever w/night sweats, weight loss, chonic cough,
    bloody sputum
    Causative Agent - Mycobacterium tuberculosis, gram
    positive, slender bacillus, slow growing
    Pathogenesis - Inhalation of
    airborne organisms, taken up by pulmonary macrophages in the lungs,
    carried to lymph nodes, 2 weeks later, severe immune response occurs,
    causes death of tissue resulting in "cheesy" material
    Epidemiology -
    10M americans infected, mostly non-white, elderly poor people, need as
    little as 10 inhaled organisms
    Prevention - No vaccine in US due to
    TB test
    Treatment - Antibiotic treatment given in cases of active
    tuberculosis, 6 month therapy, 2 or more medications
  14. Symptoms - short incubation, headache, fever, muscle pain, dry cough.
    Symptoms besides fatigue may leave in 1 week.
    Causative agent -
    Influenza A Virus, single stranded RNA genome
    Pathogenesis -
    Respiratory secretions, attaches to cell via hemagglutinin spikes
    - Outbreaks occur Fall - Spring every year, Virus undergoes antigenic
    drift, causing minor changes in spikes
    Prevention - Vaccination
    - Antiviral medications Amantidine and Rimantidine
  15. Symptoms - Acute fever, lower back muscle ache, nausea/vomitting,
    diarrhea. Later shortness of breath, shock and death
    Causative agent
    - Hantavirus, single stranded RNA genome, enveloped, lifetime infection
    in rodents
    Pathogenesis - Inhalation of dust contaminated with
    rodent urine, feces and saliva. Infects cells that line capillaries.
    Inflammation in capillaries causes fluid to leak into the lungs. 40% of
    patients die from shock.
    Epidemiology - Emerging disease/recent
    discovery, most cases occur west of MS river, outbreaks correlate to
    increase in deer mouse population
    Prevention - Minimizing exposure
    - None
    Hantavirus Pulmonary Syndrome
  16. 123 known cases between 1996 - 2004
    High mortality rate among infants
    avian virus
    Vaccines currently being developed
    Bird Flu (Avian Influenza)
Card Set
22 - Respiratory System Infections
22 - Respiratory System Infections