Pneumonia Flashcards
What is pneumonia?
Inflammatory condition of the lungs caused by infection
What does pneumonia lead to?
Fluid and blood cells leaking into the alveoli.
The infection spreads across the alveoli and eventually the lung tissue becomes consolidated, impairing the gas exchange due to reduced ventilation.
What are the three types of pneumonia?
Bronchopneumonia = patchy throughout 1 lung
Lobar pneumonia = consolidation in entire lobe
Interstitial pneumonia - inflammatory - viral
What does severe bronchopneumonia/lobar pneumonia not respond to?
Large consolidation -> shunt V=0
Does NOT respond to O2
What does bronchopneumonia respond to?
V/Q mismatch
Responds to O2
What is the most common cause of pneumonia?
Streptococcus pneumonia, which is generally community-acquired
Presentation
Shortness of breath
Cough productive of sputum
Fever
Haemoptysis
Pleuritic chest pain (sharp chest pain worse on inspiration)
Delirium (acute confusion associated with infection)
Sepsis
Signs
There may be a derangement in basic observations. These can indicate sepsis secondary to the pneumonia:
Tachypnoea (raised respiratory rate)
Tachycardia (raised heart rate)
Hypoxia (low oxygen)
Hypotension (shock)
Fever
Confusion
Chest signs of pneumonia
Bronchial breath sounds.
Focal coarse crackles.
Dullness to percussion due to lung tissue collapse and/or consolidation.
Hospital acquired pneumonia
Lower respiratory tract infection that develops more than 48 hours after hospital admission.
What are the most common organisms that cause HAP?
Pseudomonas aeruginosa
Staphylococcal aureus
Enterobacteria
Aspiration pneumonia
This occurs in patients with an unsafe swallow.
Risk factors include stroke, myasthenia gravis, bulbar palsy, alcoholism, and achalasia.
On chest x-ray the right lung is most commonly affected, as the right bronchus is wider and more vertical than the left bronchus, making it more likely to facilitate the passage of aspirate.
Staphylococcal pneumonia
A gram-positive cocci found in clusters.
It is found in intravenous drug users, elderly patients, or patients who already have an influenza infection.
Mycoplasma pneumoniae
This causes a milder pneumonia and can cause a rash called erythema multiforme characterised by varying sized “target lesions” formed by pink rings with pale centres.
It can also cause neurological symptoms in young patient in the exams.
Chlamydophila pneumoniae
School aged child with a mild to moderate chronic pneumonia and wheeze.
Be cautious though as this presentation is very common without chlamydophilia pneumoniae infection.
Coxiella burnetii
This is linked to exposure to farm animals and their bodily fluids.
The MCQ patient is a farmer with a flu like illness.
AKA Q fever
Chlamydia psittaci.
This is typically contracted from contact with infected birds.
The MCQ patient is a from parrot owner.
What is atypical pneumonia?
Caused by an organism that cannot be cultured in the normal way or detected using a gram stain.
They don’t respond to penicillins and can be treated with macrolides or tetracyclines.
How to remember causes of atypical pneumonia?
Legions of psittaci MCQs”
M – mycoplasma pneumoniae
C – chlamydydophila pneumoniae
Qs – Q fever (coxiella burnetii)
What is Pneumocystis jiroveci (PCP)?
Fungal pneumonia
Who does Pneumocystis jiroveci (PCP) occur in?
Immunocompromised.
It is particularly important in patients with poorly controlled or new HIV with a low CD4 count.
Investigations
Chest xray
FBC (raised white cells)
U&Es (for urea)
CRP (raised in inflammation and infection)
Investigations in moderate or severe cases
Sputum cultures
Blood cultures
Legionella and pneumococcal urinary antigens (send a urine sample for antigen testing)
Antibiotics
Mild CAP: 5 day course of oral antibiotics (amoxicillin or macrolide)
Moderate to severe CAP: 7-10 day course of dual antibiotics (amoxicillin and macrolide)
Complications
Sepsis
Pleural effusion
Empyema
Lung abscess
Death
Severity assessment
C – Confusion (new disorientation in person, place or time)
U – Urea > 7
R – Respiratory rate ≥ 30
B – Blood pressure < 90 systolic or ≤ 60 diastolic.
65 – Age ≥ 65
Out of hospital - do not count urea
What does CURB 65 predict?
Mortality
Score 1 = under 5%
Score 3 = 15%
Score 4/5 = over 25%
What should you do based off of CURB-65 scores?
Score 0/1: Consider treatment at home
Score ≥ 2: Consider hospital admission
Score ≥ 3: Consider intensive care assessment
Treatment
Oxygen to keep O2 saturations above 94%
Fluid management
Analgesia if patients have pleuritic chest pain. Paracetamol 1g/6 hours (Max. 4g 24hours)
Antibiotics can be given orally for patients who are not nil by mouth and are managed in the community. However, for severe pneumonia Intravenous route is required.
Follow up appointments are organized for 6 weeks and CXR could be repeated at this time if there are complications or symptoms have not resolved.
Prevention
Pneumococcal vaccine protects against Streptococcus pneumoniae
When is the pneumococcal vaccine offered?
Three injections at the age of 2 months, 4 months and 12-13 months.
Who should be offered the pneumococcal vaccine?
People aged 65 years and older and those in at-risk groups
What is a sign of streptococcus pneumoniae?
Rusty brown sputum
Differential diagnosis
Tuberculosis
Lung cancer
Pulmonary embolism
Pulmonary odema
Pulmonary vasculitis
What is bronchopneumonia?
Most common pneumonia found in children
Accounts for 85% of all respiratory system diseases in children under two years of age
Bronchopneumonia is a type of pneumonia that causes inflammation in the alveoli.
What is the most common cause of death in children under 5?
Bronchopneumonia
What causes bronchopneumonia?
Staphylococcus aureus, Klebsiella pneumoniae, Haemophilus influenzae, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Escherichia coli.
What are the symptoms of bronchopneumonia?
Productive cough
Purulent sputum
Dysepnea
Rigor
Pleuritic pain
What is lobar pneumonia?
Non-segmental pneumonia
Radiological pattern associated with homogeneous and fibrinosuppurative consolidation of one or more lobes of a lung in response to bacterial pneumonia
What are the three types of pneumonia?
Bronchopneumonia = patchy throughout 1 lung
Lobar pneumonia = consolidation in entire lobe
Interstitial pneumonia - inflammatory - viral
What are the risk factors for pneumonia?
Smoking
XS alcohol
Extremes of age
Preceding viral illness
Pre-existing lung condition (COPD, CF)
Chronic illnesses, immunocompromised (HIV, cancer therapy)
Hospitalisation (after 40 hours)
IV drug users
What causes rusty brown sputum?
Strep pneumoniae
Signs of pneumonia complications
Swinging fevers
Sweats
Raised WCC/CRP
Weight loss
Failure to improve
Treatment for CURB-65 score of:
0-1
Community treatment
Amoxicillin
If patient has a penicillin allergy, prescribe clarithromycin or doxycycline
5 day course of antibiotics
Treatment for CURB-65 score of:
2
Hospital treatment
Amoxicillin + clarithromycin (atypicals)
If patient has a penicillin allergy, prescribe levofloxacin
5-7 day course of antibiotics
Treatment for CURB-65 score of:
3 or more
ITU
Co-amoxiclav + clarithromycin
If patient has a penicillin allergy, prescribe levofloxacin or co-trimoxazole
7-10 day course of antibiotics
Aspiration pneumonia treatment
Anaerobes
Use amoxicillin + metrodinazole
What are the causative agents in community acquired typical pneumonia?
S. pneumoniae
H. influenxae
Discuss S. pneumoniae
Accounts for 80% of cases
Particularly associated with high fever, rapid onset and herpes labialis
A vaccine to pneumococcus is available
Who is H. influenzae seen in?
Those with COPD
COPD exacerbation
Klebseilla pneumonia
Primarily affects the upper lobes resulting in a cavitating pneumonia, presenting with “red-currant” sputum.
It is caused by a gram-negative anaerobic rod.
Furthermore, there is an increased risk of developing complications including empyema, lung abscesses and pleural adhesions.
Patients at risk of Klebsiella pneumonia are those with weakened immune systems such as elderly, alcoholics, and diabetics.
Additional at-risk groups include patients with malignancy, chronic obstructive pulmonary disease, long term steroid use and renal failure.
