Respiratory Tract Infections Flashcards
Function of the Upper RS?
- filter air and collect particles
- non-sterile
- normal flora, competes with pathogens to help protect us
- some pathogens can live within normal flora and when it goes to other parts of the body infection can occur
Immune system in the upper RS? Is the upper RS sterile?
-large as it is a portal of entry
need strong immune system effects here
-it is non-sterile
Components of the upper RS?
- tonsils, mucous
- uvula
- pharynx
- nasal cavity
- auditory tube opening
Function of the Lower RS? is it sterile or on-sterile?
- sterile
- good immune response
- gas exchange
- highly vascularized
- antibodies present at all times
Why is it easy for pathogens to cause systemic infection if located in the lower RS?
-highly vascularized, can entry blood plasma easily
What causes cough reflex when you aspirate in the lower RS?
-ciliary escalader
Components of the lower RS?
- epiglottis
- larynx
- trachea
- pleurae
- bronchiole
- diaphragm
Upper RT infections: Bacterial
- pharyngitis
- otitis media
- rhino sinusitis
Causes of pharyngitis? symptoms? how is it treated?
- streptococcus pyogenes
- sore throat
- treated with antibiotics if bacterial
Cause of otitis media?
- middle ear infection
- streptococcus pneumonias
- already present in middle ear not causing damage, but when immune system is compromised or weakened, host defences change. it can cause damage
Cause of rhino sinusitis?
- infection of sinuses
- haemophilus influenza
Are most URTI bacterial or viral?
-most are viral
4 viral URTI’s?
- pharyngitis
- otitis media
- rhino sinusitis
- common cold
Streptococcal Pharyngitis signs and symptoms?
- red pharynx
- swollen lymph nodes
- pain during swallowing
- fever
- headache
- bad breath
Rapid strep throat swab?
- 15 can tell whether it is bacterial or viral
- tells us fast and early so it doesn’t grow into super antigen and turn into scarlet fever, producing damaging effects to the heat and kindeys
Is streptococcus progenies bacterial or viral? what can it produce if it grows rapidly?
- bacterial
- can produce erythrogenic toxins that can damage heart and kidneys
Signs and symptoms of Scarlett fever?
- sandpapery rash on neck and chest and then spreads throughout the body
- red tongue
Otitis media signs and symptoms? what happens if ear drum ruptures? who are most susceptible to ear infections?
-Inflammation and pressur eon ear drum
-ear pain
rupture= earring impairment
-most common in young patients, decrease as you age
Green mucous represents?
-bacterial infections
Signs and symptoms of rhino sinusitis? Most common in what age group?
- sinus pain and pressure
- headache
- feeling of malaise
- adult cases
Common bacterial pathogenic microorganism causing otitis media and rhino sinusitis?
- Streptococcus pneumonia
- 10% of cases (90% are viral causes)
- more likely to be bacterial if high fever and pus nasal discharge for more than 10 days
Streptococcus pneumoniae?
- main bacterial pathogen
- infections move from pharynx to sinuses (sore throat) or to middle ear
- risk of sepsis and meningitis
Are common cold caused by viruses or bacterium? Signs and symptoms?
-always viral
-dry congested nasal
scratchy sore throat
-cough for about 1 week
-NO FEVER
common cold: how does it exit? is it contagious
- infects for hours, exits cells through lysis
- highly contagious
- caused by multiple viruses
Transmission of the common cold? how to prevent it?
-respiratory droplets direct contact -single virus can cause infection -live on door knobs and handles -hand washing prevents it
What causes the sore throat with he common cold?
-cell lysis when virus leaves the host cells
Is there a fever with the common cold? if there is what is it indicative of?
- no there is no fever
- indicative of bacterial infection present
What is the most common cause of death by infection in the world? 6th leading cause of death in Canada
-Pneumonia
Pneumonia? Who does it affect the most?
- LRT Infection
- fluid in bronchioles and alveoli causing dyspnea
- mainly affects the very young and the very old
- long staying hospitalized patients can develop it (HAI)
When is pneumonia most common?
- fall and winter (times when flu risk is high)
- influenza causes damage to alveoli linings making it susceptible for diseases
Pneumococcal pneumonia? what are 75% of people colonized with?
- 85% of community cases
- 75% of people have stretococcus pneumonia in normal flora, infection develops when it is not cleared by immune system, host defences are down etc.
Pneumonia risk factors?
- drug abuse
- alcoholism
- HF, DM, AIDS
- immunosuppressive drug therapies
Why are drug addicts and alcoholics at risk for developing pneumonia?
-cough reflex is suppressed (innate immune system is impaired), can micro aspirate into the LRT
What are 85% of community acquired pneumonia (CAP) caused from?
-streptococcus pneumonia which causes pneumococcal pneumonia
Leading cause of pneumonia in hospital acquired pneumonia?
-gram negative bacterium
Common causes of pneumonia in nursing homes?
- S. pneumoniae
- gram negatives
- viruses
Streptococcus pneumoniae?
- gram positive bacteria
- coccoid shaped
- produce adherence factors help bind to pharyngeal epithelia cells
- can cause endocytosis of the lungs
- produces cytotoxin (pneumolysin) can induce cell lysis
CAP: pneumococcal pneumonia?
Signs and Symptoms?
sputum colour?
-transmission by respiratory. dropplets
-S. pneumoniae damages alveolar lining
-RBC and WBC enter lungs
fluid in alveoli and inflammation impair gas exchange
-fever
-chills
-congestion
-cough
-chest pain
-SOB
-sputum= rust coloured from RBC and there is an increased neutrophil count in it as well
CAP: mycoplasma pneumoniae?
Signs and Symptoms?
What is it also known as?
-primary atypical pneumonia
-dropplet transmission
direct contact
-not seasonality
-young adults mostly
-not associated with S. pneumonia
-damages ciliary escalator, can’t get rid of mucous from RT (adhesions specific for cilia of resp. epithelial cells)
-fever (lower than CAP
-headache
-sore throat
-sweating
-non-progressive cough
-thick sticky mucous
-“walking pneumonia”
Viral pneumonia?
2 ways viruses can leads to pneumonia?
Signs and Symptoms?
-influenza diminishes immune system parainfluenza virus transmission by respiratory. droplets 1. primary viral pneumonia 2. resp. infections followed by bacterial super-infections -non-productive cough, fever, fatigue, sore throat headaches -antivirals not effective -not much we can do
How to definitively diagnose pneumonia?
-chest X-RAY
Chest X-RAY?
- along with signs and symptoms will diagnose pneumonia
- blackness=air
- white= fluid/pus
- no infiltrastes/ pus/fluid= no pneumonia
Negative chest X-RAY bust still have pneumonia?
- dehydrated people show low us accumulation in the lungs
- rehydrate the patient then perform chest X-RAY again
What tests to look at / for to diagnose pneumonia?
-chest x-ray
-signs and symptoms
-determine severity, complications, status of underlying conditions
-arterial blood gas analysis
-CBC
-electrolytes
-renal and liver function tests
-blood cultures
sputum gram stain
Mortality rate % for being hospitalized 30 days
-15%
CURB-65: Confusion Urea Respiratory Rate BP- age of 65?
- measures the severity of the pneumonia
- points given for confusion, BUN greater than or equal to 19mg, RR greater than 30, systolic pressure less than 90, diastolic less than 60, over the age of 65
CURB-65: score of 0,1,2,3,4,5
0=low risk 1=low risk 2=short hospitalization 3=severe pneumonia 4 or 5= sever pneumonia (consider ICU)
Empyema?
-pus accumulation in pleural cavity
Antibiotic therapy for pneumonia? Why should you also administer systemic corticosteroid therapy?
- consider antibiotic exposure in the past 3-6months to help reduce antibiotic resistance
- find antibiotic responsible for that specific pathogen
- CST= massive inflammation is harmful to us, corticosteroids reduces rate of mechanical ventilation, respiratory distress, duration of hospitalization
3 ways to help prevent pneumonia?
- hand washing
- annual flu vaccine
- pneumococcal vaccines (help decrease complications associated with pneumonia
When is pneumococcal disease most prevalent in elderly patients? why?
- Holidays/ Christmas
- family/ lots of contact
- kids colonized with streptococcus pneumonia can pass it on to susceptible grandparents and they can get sick
Efficacy of Pneumococcal Vaccine?
-doesn’t prevent pneumonia
-some think it reduced risk of invasive pneumococcal disease
cheap and safe
reduces hospitalization rates
recommended for elderly over the age of 65
TB world-wide stats? % of world infected with TB?
- most common infectious cause world wide
- 30% of people have it in the world
Mycobacterium TB? How to identify it?
-rod shaped aerobic bacteria -need acid fast stain to identify it -some can survive in acidic and basic conditions -resistant to dry conditions -airborne precautions needed risk fo transmission is high
Transmission of TB? # types of 3 TB?
airborne droplets
- inhaled
- infective dry aerosol droplets can survive up to 8 months
- dry sputum travels in air longer because it is lighter in weight than wet sputum
- primary, secondary and disseminated TB
Primary TB?
- inhalation and depositing bacilli in lungs
- 5% of people will develop active TB
- mostly in children
- actively sick and infectious
Primary Pulmonary TB?
- serious productive cough (blood and sputum)
- lasts 3 weeks or longer
- chest pain
- fatigue
- weight loss
- loss of appetite
- chills
- fever
- night sweats
- positive chest X-RAY and sputum
Latent TB?
- 95% get this kind
- immune system prevents spread of infection
- asymptomatic
- negative chest X-RAY
- present with positive TB test and antibodies present
- IF NOT TREATED IT CAN DEVELOP INTO ACTIVE TB
Isoniazid?
-used to treat latent TB for 6-9 months
TB skin test? Positive? Negative?
TB skin test= antigen injected into skin
-48-72hrs post injection client assessed for reaction
Positive= hard, red selling at site of injection. client infected with TB
Negative= no reaction, latent TB is unlikely
-lacks utility in active TB (thus active TB is screened as negative)
Secondary TB? mortality rate if treated vs no treatment?
- latent infection becomes active
- blood and sputum in productive cough
- cough lasts 3 weeks or longer
- chest pain present
- weakness
- weight loss
- chills
- fever
- positive chest X-RAY
- 15% mortality if treated, 55 mortality if untreated
Best diagnostic tools for active pulmonary TB?
- early AM sputum
- induced sputum (saline aerosols)
- gastric aspirates if no sputum production possible
- suck out sputum form lungs (less accurate, more invasive)
TB: risk of re-activation?
5-10%
People at risk for TB?
-HIV
-infected with TB in last 2 years
-young children and babies
-people who inject illegal drugs
-immunocompromised patients
elderly people
Disseminated TB?
- moves from one site of body to another
- brain, spine, kidneys, lymph nodes
Consider TB when…?
- unexplained weight loss
- loss of appetite
- night sweats
- fever
- fatigue
- non-resolving pneumonia
Treatment of TB?
- 6-9 months
- isoniazid, rifampin, ethambutol, pyrazinamide
- monitor liver and kidneys for drug toxicity
- evaluate response to treatment
Pneumonia and immunocompromised hosts?
-increased risk
-underlying diseases or therapy
bacterial, viral, fungal or parasitic pneumonia
What is pneumocystis caused by? mainly associated with what immunosuppressant disease?
- pneumonia caused by yeast-like fungus
- mostly associated with AIDS
