Pneumonia

Question 1

Pneumonia definition

Answer 1

Pneumonia is an acute inflammation of the terminal bronchioles and the area surrounding the alveoli.

Question 2

Epidemiology of pneumonia

Answer 2

0.5-1% of people develop CAP in the UK every year, with mortality between 5-14%

Question 3

Bacteria that cause pneumonia

Answer 3

• MRSA
• TB
• Streptococcus pneumoniae
• Haemophilus influenzae
• Staphylococcus aureus
• Klebsiella pneumonia
• Pseudomonas aeruginosa

Question 4

What viruses cause Pneumonia?

Answer 4

• Respiratory syncytial virus (RSV)
• Influenza

Question 5

What fungi cause pneumonia?

Answer 5

Pneumocystic jirovicii

Question 6

What are idiopathic intersitial pneumonias?

Answer 6

group of non-infective causes e.g. cryptogenic organising pneumonia which may occur as a complication of rheumatoid arthritis or amiodarone use.

Question 7

RFs for Pneumonia

Answer 7

• Extremes of age: young children and the elderly are particularly at risk
• Preceding viral infection
• Immunosuppressed: e.g. due to steroid use
• Intravenous drug abuse:Staphylococcus aureus
• Respiratory conditions: asthma, COPD, malignancy, cystic fibrosis

Question 8

Pneumonia is secondary to inflamamtion, what does inflammation do in the lungs?

Answer 8

brings water into the lung tissue, which makes it harder to breathe.

Question 9

What do microbes do in pneumonia?

Answer 9

• Enter and evade body defences
• Multiply and cross over from airways into lung tissue > inflammatory respionse

Question 10

What happens to lung tissue as it inflammed?

Answer 10

tissue fills with white blood cells as well as proteins, fluid, and red blood cells if a nearby capillary is damaged in the process.

Question 11

Pneumonias categorised by how its acquired - what are the 2 types of pneumonia?

Answer 11

• Community acquired pneumonia (CAP): pneumonia acquired outside a hospital setting
• Hospital-acquired pneumonia (HAP): pneumonia that develops more than 48h after hospital admission

Question 12

What is aspiration pneumonia?

Answer 12

• due to foreign material lodging in the lungs.
• Microbes on the foreign material can cause infection.
• Aspiration pneumonia can also happen with drinks, or vomiting of gastric contents.

Question 13

What is atypical pneumonia?

Answer 13

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 (e.g. clarithomycin), fluoroquinolones (e.g. levofloxacin) or tetracyclines (e.g. doxycycline).

Question 14

What is bronchopneumonia?

Answer 14

infection can be throughout the lungs involving the bronchioles as well as the alveoli.

Question 15

What is atypical/interstitial pneumonia?

Answer 15

infection is mainly just outside the alveoli in the interstitium.

Question 16

What is lobar pneumonia?

Answer 16

infection causes complete consolidation of a whole lobe of the lung.

Question 17

S + S of Pneumonia

Answer 17

Pyrexia
Tachycardia
Hypoxia
Dyspnoea
Fever
Pleuritic chest pain
Productive cough

Question 18

Primary investigations for pneumonia

Answer 18

• CXR
• FBC:leukocytosis
• U&Es:deranged in severe disease
• CRP:raised
• ABG:perform if hypoxic to assess for respiratory failure
• Sputum culture:allows assessment of organism and antibiotic sensitivities

Question 19

What is CURB-65?

Answer 19

Criteria for pneumonia - nazias note good explanation

Question 20

Initial management for Pneumonia

Answer 20

• O2, if needed
• Analgesia
• Antibiotics: will vary by trust

Question 21

Management for Community acquired pneumonia

Answer 21

• Low severity (CURB ≤ 1):oral amoxicillinORdoxycycline/clarithromycin if penicillin-allergic or an atypical pathogen is suspected; usually a 5 day course
• Moderate severity (CURB 2): amoxicillin;addclarithromycin if an atypical pathogen is suspected; usually a 5 day course
• High severity (CURB ≥ 3):IV co-amoxiclavandclarithromycin are often used

Question 22

Treatment for Hospital acquired pneumonia

Answer 22

Severity is determined clinically

• Low severity:oral co-amoxiclav
• High severity:a**broad-spectrum antibiotic, such as IV tazocin or ceftriaxone
• Suspected or confirmed MRSA:add vancomycin

Question 23

When should you not discharge a patient with CAP?

Answer 23

if in the last 24 hours they have had 2 or more of the following:

• Temperature > 37.5°C
• RR ≥ 24
• HR ≥ 100
• SBP ≤ 90 mmHg
• SpO2≤ 90% on room air
• Abnormal mental status
• Inability to eat without assistance

Question 24

Complications of Pneumonia

Answer 24

• Acute respiratory distress syndrome:associated with a 30-50% mortality rate and usually requires mechanical ventilation
• Sepsis:complicates severe CAP and may be fatal, particularly in immunocompromised patients
• Lung abscess:may require prolonged antibiotic therapy and drainage; can occur due toKlebsiellaorStaphylococcalpneumonia
• Pleural effusion:parapneumonic effusions can either be sterile or infected (empyema

Question 25

Most common community acquired pneumonia bacteria

Answer 25

Streptococcus pneumonia - 80% of pneumonia Haemophilus influenza - COPD assosciate SA - causes secondary bacterial infection

Question 26

Common bacteria for HAP

Answer 26

Gram negative bacteria and SA

Question 27

Aspirational pneumoniae bacteria

Answer 27

Klebsiella pneuomniae Streptococcus pneumoniae SA

Question 28

What is pneumocystis pneumonia?

Answer 28

Pneumocystis pneumonia (PCP) is an opportunistic respiratory infection caused by the fungus, Pneumocystis jirovecii.

Question 29

PCP epidemiology

Answer 29

- PCP is the most common opportunistic infection in patients with AIDS. - 40% of people with PCP have HIV/AIDS, whilst the remaining people are typically immunosuppressed due to conditions such as leukaemia, inflammatory diseases and solid organ transplantation.

Question 30

RFs for PCP

Answer 30

- **HIV/AIDS**: PCP is associated with a CD4 count < 200/mm^3 - **Primary immunodeficiency conditions** - **Secondary immunodeficiency**: e.g. steroids - **Other causes of immunosuppression**: e.g. haematological malignancies

Question 31

S + S of PCP

Answer 31

CXR often normal Lymphadenopathy Hepatosplenomegaly Dyspnoea Pyrexia Cough Fever

Question 32

Primary investigations for PCP

Answer 32

- **Oxygen saturation:** patients with PCP characteristically desaturate on exertion - **Arterial blood gas:** type 1 respiratory failure - **Chest X-ray:** may reveal bilateral interstitial infiltrates but can be normal - **Induced sputum:** silver staining to identify PCP

Question 33

Other investigation for PCP

Answer 33

Broncho-alveolar lavage High res CT chest HIV serology and CD4 count

Question 34

Treatment for PCP

Answer 34

- **Trimethoprim/sulfamethoxazole (co-trimoxazole):** first-line therapy - **Prednisolone:** indicated if hypoxic with pO2 < 9.3 kPa, to reduce the risk of respiratory failure (< 50% risk) and death - **IV/ nebulised pentamidine:** this is reserved for severe cases where co-trimoxazole is contraindicated or has failed -

Question 35

Prophylaxis for PCP

Answer 35

Trimethoprim/sulfamethoxazole (co-trimoxazole): primary prophylaxis is recommended in all patients with a CD4 < 200/mm3 or a history of an AIDS-defining illness