Lower respiratory tract infections Flashcards
define lower respiratory tract infection.
respiratory tract infections below the larynx
what are the common predisposing factors that lead to a Lower respiratory tract infection occurring.
loss or suppression of cough reflex (pathogen is not removed). Cillary defects mucus disorders pulmonary odema immunodeficency macrophage function inhibitiom aspiration of food.
common bacterial organism which cause lower respiratory tract infections
streptococcus pnemonia haemophilus influenz staphylococcus aureus klebisella pneumona Mcyoplaasma pneumonaie Legionella pneumophila Mycobacterium tuberculosis.
common viral organisms which cause lower respiratory tract infections
Influenza
Parainfluenza
Respiratory syncytial virus- RSV
Adenovirus
common fungal infections which cause lower respiratory infections
aspergillus, candida, pneumocytisis jiroveci.
define acute bronchitis
• Inflammation and oedema of trachea and the bronchi
clinical signs of acute bronchitis
cough (dry), dysponea, tachyponea, retrosternal pain
common pathogens which cause acute bronchitis and chronic bronchitis.
viral- common
rhinovirus, coranavirus, adenovirus and influenza
bacteria- rare
H. infleunza, M. pneumonia, B, pertussis.
diagnosis of acute bronchitis
vaccination history and previous exposure- to eliminate organisms
culture of respiratory secretions to isolate cause
treatment for acute bronchitis
supportotive
oxygen therapy-immuneocompromised
antibiotics is bacterial
define chronic bronchitis
cough productive of sputum on most days during atleast 3 months of 2 successive years (which cannot be attributed to alternative cause)
what factors contribute to developing chronic bronchitis
sex- men age- over 40 smoking pollution allergens- in particular.
In what age group is bronchioloitis common
children- narrow bronchioles
define bronchiolitis
• Inflammation and oedema of the bronchioles
clinical signs of bronchiolitis
acute onset wheeze, cough, nasal discharge, respiratory distress (grunting, retractions, and nasal flaring.
most common pathogen which causes bronchiolitis
RSV
diagnosis of bronchiolitis
chest X-ray
FBC
Microbiology
nasopharyngeal aspirate
Treatment for bronchiolitis
supportive- oxygen
antibiotic is bacterial
define pneumonia
• Infection of distal airway and alveoli- form inflammatory exudate
2 anatomical patterns of pneumonia
– Bronchopneumonia- patchy distributed around bronchioles and spread to alveoli.
– Lobar pneumonia-90% due to s. pneumniae, affects large part of the lung, line demarcation and consolidation.
4 ways in which pneumonia can be caused
community acquired-most common
hospital acquired
Ventilator acquired pneumonia
Aspiration pneumonia
what defines hospital acquired pneumonia
• Pneumonia developing >48hrs after hospital admission
what defines hospital ventilator pneumonia
• Subgroup of HAP
• Pneumonia developing >48hrs after ET intubation & ventilation
common when not breathing well
what defines aspiration pneumonia
subgroup HAP or CAP.
• Pneumonia resulting for the abnormal entry of fluids e.g. food, drinks, stomach contents, etc. into the lower respiratory tract
• Common is patients unconscious
how is CAP pneumonia transmitted
Person-to-person or from a person
from environment
from animals
what organism cause CAP pneumonia
Atypical • Mycoplasma pneumoniae • Legionella pneumophilia • Chlamydophila pneumoniae • Chlamydophila psittaci • Coxiella burnetii Typical • Streptococcus pneumoniae • Haemophilus influenzae • Moraxella catarrhalis • Staphylococcus aureus • Klebsiella pneumoniae
clinical signs and symptoms of pneumonia
• Rapid onset • Fever/chills-rigors • Productive cough- blood or purulent. • Mucopurulent sputum • Pleurtitic pain- lung parenchyma is infected and inflamed, and on deep inspiration it rubs against the pleura • General malaise-fatigue and anxiety. tachypnoea, tachycardia, hypotension
what is found upon examination of a patient with pneumonia
dull to percuss (consolidation) and reduced air entry, bronchial breathing.
main symptom of mycoplasma pneumonia
cough
rare complications of mycoplasma pneumonia
guillian- barre, peripheral neuropathy
mycoplasma pneumonia is common in which age group
children
Chlamydophila pneumoniae is common in which age group
elderly
what are outbreaks of legionella pneumophilla associated with
Colonises water piping systems
Outbreaks associated with showers, air conditioning units, humidifiers
signs of legionella pneumophilla
High fevers, rigors, cough: dry initially becoming productive, dyspnoea, vomiting, diarrhoea, confusion- low GCS.
Bloods: deranged LFTs, SIADH (low sodium)
what animal exposure is Chlamydophila psittaci associated with
birds
signs of Chlamydophila psittaci
rash, hepatitis, haemolytic anaemia, reactive arthritis, spleenomegaly.
what is the recover time from influenza
2-3 weeks
symptoms of influenza
– Fever, headache, myalgia (pain in muscles) and sore throat
primary viral pneumonia occurs most commonly in what types of people
people with pre-existing cardiac or lung problems (heart failure of COPD)
What the of infections commonly occurs after a primary viral pneumonia
– Secondary bacterial pneumonia then may develop after initial period of improvement:- COMMON as viral infection damages the lung so it is an opportunity for bacteria to colonise.
3 most common pathogens which cause secondary bacterial pneumonia
– S.pneumoniae, H.influenzae, S.aureus
diagnosis of influenza
viral antigen detection in respiratory samples using PCR.
treatment for influenza
no treatment
non microbiological investigations for CAP
routine observations- BP/Pulse/Oximetry
Blood: FBC/U and E, CRP, LFT
Chest X-ray.
Microbiological invesitagtions for inpatients for CAP
– Sputum gram stain and culture- see what the organism is.
– Blood culture- if serious as the pathogens has multiplied in the lung and then reached the blood supply.
– Pneumococcal urinary antigen
– Legionella urinary antigen
PCR for viral pathogen, mycoplasma pneumoniae, chlamydophilia
what assessment is used to determine the disease severity of CAP
CURB65 Confusion Urea Respiratory rate Blood pressure Age> 65 years
which 2 vaccine prevent lower respiratory tract infections
- Pneumococcal vaccination (S. pneumoniae)
* Influenza vaccination for vulnerable groups (annually)
Management of CAP
A- airway- open and patent
B-breathing- reap rate, oxygen saturation
C-circulation- BP and heart rate, urinary catheter to measure output.
antibiotics given depends on CURB65 score.
which groups of patients are given the pneumococcal vaccination
– Patients with chronic heart, lung and kidney disease
– Patients with splenectomy
which groups of patients are given the influenza vaccine
– Over 65s
– Chronic disease, multiple co-morbidities e.g. diabetes.