What are the three primary defenses of the respiratory system?
mucocillary escalator: traps debris and bacteria, which are then moved to the esophagus and out the respiratory system --> problem viral infections can disrupt the function of respiratory epitheium, which allows bacteria to enter respiratory system
Aveolar macrophages are in important part of the host defense --> problem: bronchial carcinoma can obstruct a bronchus and infection can arise behind obstruction
Muscle of the chest wall and diaphragm are important in coughing and cleaning secretions from the respiratory system --> problem: trauma or abdominal surgery
What are the virulence factors of Streptococcus pyogenes?
a.) mucousal surfaces are a coated w/ fibronectin and normal flora. Remval of this layer allows gram-neg bacteria to colonize the oropharynx in significant #'s
b.) some ofthe contibutory factors for nosocomial pneumonia
what is this a picture of?
The influenza A virus
What are the three ways influenza can kill?
underlying disease: people w/ limited cardiovascular activity or pulmonary function
superinfection: bacterial pneumonia and dissiminated bacterial disease
direct rapid progression: overwhelming viral pneumonia and asphxia
What causes diphtheria to be fatal?
development of pseudo membrane- blocks throat, like seran wrap → suffocation
Toxemia can make diptheria life threatening: can involve multiple organ systems; can cause acute myocarditis → systemic infection
how is diptheria transmitted?
droplet aerosol
direct contact
fomiites (lesser degree)
key things to know about nosocomial infections?
hospital acquired
occurs 48 hours after hospital admission
associated w/ S. Aureus
caused by gram - bacteria
what is community aquired pneumonia known as? and its s/s?
lobar pneumonia
s/s: fever, chest pain, purulent sputum
what are the 4 stages of lobar pnumonia and describe them?
Acute congestion- local cappillaries become engorged w/ neutrophils
Red hepatization- RBCs from the capillaries flow into the alveolar spaces
Grey hepatization- large # of dead neutrophils and degenerating red cellss
Resolution- adaptive immune response begins to produce antibodies (control the infection)
key things to know about Mycoplasma pneumonia
bacteria that lacks a cell wall
mild form
caused by mycoplasma pneumoniae
accounts for 10% of all pneumonia
“walking pneumonia”
no need for hospitalizationmost
common age 5-15: causes 30% of all teenage pneumonias
key things to know about Chlamydial Pneumonias
caused by chlamydia pneumoniae
responsible for 10% of pneumonia cases and 5% of bronchits cases
occurs through-out the year
spread person to person contact
more infections in the elderly
causes both nosocomial and community acquired
Know the causative agents and identifying signs/symptoms of the following diseases: strepthroat
pharyangitis
Causative agent (most common): strep. pyogenes (can lead to scarlet fever)
S/S: sneezing, cough, watery eyes, mild headache, mild body aches, runny nose, low grade fever (these are from the CDC website... the book said nothing about it and neither did her ppt!)
Know the causative agents and identifying signs/symptoms of the following diseases: scarlet fever
Causative agent= strep. pyogenes
s/s: begins with a rash over entire body and usually appears redder in the armpits and groin areas. rash lasts 2-5 days. flushing and very sore throat which can be accompanied by yellow or white papules. fever of 101or higher and lympadenopathy in neck region. headache body aches, and nausea can occur
Know the causative agents and identifying signs/symptoms of the following diseases: diptheria
causative agent= Coryenbacterium diptheriae (a potent inhibitor of protein synthesis)
S/S:it is a localized infection, usually presents as severe phargyntitis or tonsilittis, accompanied by a plaque-like pseudomembrane in the throat. Accompanied by fever, sore throat and malaise. membrane should be coughed up in 5-10 days.
tx: toxin neutralization/elimination
Know the causative agents and identifying signs/symptoms of the following diseases: common cold rhinovirus infection
rhinovirus infection
Causative agents: There are several hundred serotypes of the rhinovirus. 50% that have been characterized are picornavirus (extremely small,
single-stranded RNA viruses that do not have envelopes, like the temp in the nasopharynx<33 degrees C>)
uses glycoprotein ICAM, which is an adhesion molecule, as a receptor to infect host cells
S/S:infection is usually mild w/ little damage to the body: sneezing, stuffy nose, sore throat, coughing, mild headaches, mild body aches, watery eyes (again from the CDC website)
Know the causative agents and identifying signs/symptoms of the following diseases: pertusis
whooping cough
causitive agents: Bordetella pertussis (gram - coccobacillus, doesn’t survive in environment, reservoir is humans, affinity for ciliated bronchial
epithelium- produces trachel toxins that immobolizes are progressively destroys ciliated cells, causes persistent cough)
has an affinity for cilitated bronchial epithelium once attached the organism produces a tracheal toxin that immobilizes and progressively destroys the cilliated cells
S/S: similar to cold
Transmission: airborne droplets from patients in the early stages
highly contagious 80-100% of exposed susceptible individuals
spreads rapidly in schools, hospitals, offices & homes
what are the four stages associated w/ pertussis?
catarrhal stage- persistent perfuse and mucoid rhinorrhea for 1-2 weeks. sneezing, malaise and anorexia. (communicable)
paroxysmal stage- strats w/ persistent coughing that can build to 50 times a day for 2-4 weeks. “whooping” is heard. increase in lymphocytes; apnea after coughing.
convalescent stage- frequency and severity of coughing and other symptoms gradually decrease
Know the causative agents and identifying signs/symptoms of the following diseases: inahalation antharax
Causitive agent: Bacillus anthracis (pneumoniagram + rod, spore-forming, spore germinate in human tissues, antiphagocytic properties of the capsule aid its survival and
growth in large numbers
)Causes fulminate pneumonia → leading to respiratory failure and deathcomes on suddenly w/ great severity
Tx w/ specific antibiotics
Pathogenesis: results from the powerful exotoxin produced
Transmission: inhaled
S/S of pulmonary anthrax: 1-5 days of non specific malaise, mild fever, nonproductive cough, progressive respiratory distress and cyanosis, rapid and massive spread to the central nervous system and bloodstream is followed by death
Know the causative agents and identifying signs/symptoms of the following diseases: Legionnaire’s disease
Causitive agent: Legionella pneumophila (gram - rod, can’t be stained or grown using normal techniques)
faculative intracellular parasite
aggrassively attacks the lungs
produces necrotizing mulifocal pneumonia
involves alveoli and terminal bronchioles
the inflammatory response produces an exudate containing: fibrin, polymorphonuclear leukocytes, and RBCs
transmission: humidified aersol from contaminated water systems
S/S:myalagia and eadachache followed by a rapidly rising fever. chills, pleuritic chest pain, vomitting, diarrhea, and occasional confusion and
delirium.
Know the causative agents and identifying signs/symptoms of the following diseases: influenza
Causitive agents: orthomyxovirus (virions are surrounded by an envelope, genome is single stranded RNA in 8 segments <allows high rate of
mutation>)
3 major serotypes of virus: A,B,C (differences based on antigens associated w/ the nucleoprotein)
S/S: fever, myalgia, headache, and occasional shaking chills; reaches its maximum severity in 6-12 hours and a non-productive cough developes
if severe enoguh it can infect the tracheobronchial tree and lungs, resulting in lethal pneumonia
Transmission: direct droplet transmission is most common
Influenza can cause death in 3 ways:
-undelying disease- people w/ limited cardiovascular activity or pulmonary function
-superinfection- bacterial pneumonia and disseminated bacterial disease
Streptococcus pneumoniae, haemophilus influenzae, staphylococcus aureus are all apart
of normal flora but are the most common bacteria responsible for superinfection
-Direct rapid progressionoverwhelming viral pneumonia and aspyxia
Know the causative agents and identifying signs/symptoms of the following diseases: HPS
Hantavirus Pulmonary Syndrome
causative agent: ??
virus causes a fulminant respiratory infection; high mortality rate (50-70%)
3 types of hantavirus:
-Sin Nombre is the most common
Transmission: inhalation of dried rodent excreta, by conjunctival route, or by direct contact through breaks in the skin
S/S: early → fatigue, fever, muscle aches (thigh hips and back), headache, dizziness, abdominal problems. late → coughing and SOB
Know the causative agents and identifying signs/symptoms of the following diseases: tb
primary tb: intitial exposuresecondary tb: occurs years later drug resistance is becoming increasingly dangerous major reason is non compliance- many pt. stop taking drugs early
S/S: initial symptoms → fever, fatigue, weight loss, chest pain, SOB, congestion w/ coughing. early detection is vital
pathogenesis: .tuberculosis cell wall interferes w/ macrophage function and T cell activation; inhibits the formation of the phagolysosome. This allows it
to escape to the cytoplasm where it increases in number; eventually spread to lymph nodes. From here it enters the blood and is distributed throughout the body
Penicillin is used to tx all of the following except?
C. mycoplasmal pneumonia
Pneumonia can be caused by all of the following except?
E. all of the above
which of the following does not produce any exotoxin?
D. mycobacterium tb
which of the following produces the most potent exotoxin?
A. corynebacterium diptheriae
the recurrence of influenza epidemics is due to
A. antigenetic shift
Legionella is transmitted by
B. airborne transmission
the patient has a sore throat. Which of the following would be involved?
what is this a picture of?