Lower Respiratory Tract Infections and Pneumonia

Question 1

What are the common microflora of the upper resp tract?

Answer 1

Viridens streptococci

Neisseria sp

Anaerobes

Candida sp

Question 2

Describe the defences of the respiratory tract

Answer 2

Nasla hair

Ciliated columnar ep

Cough/sneeze

Lymphoid follicles of the pharynx, tonsils, macrophages, secretory IgA/IgG

Question 3

When are the respiratory defences compromised?

Answer 3

Poor swallow = CVA, muscle weakness, alcohol

Abnormal ciliary function = smoking, viral infection

Abnormal mucus = CF

Dilated airways = bronchiectasis

Defects in immunity = HIV

Question 4

Name some common upper resp infections

Answer 4

Rhinitis (common cold)

Pharyngitis

Sinusitis

Most commonly causes by viruses – self limiting

Most result in secondary bacterial infections

Question 5

Name some lower resp infection

Answer 5

Bronchitis

Pneumoina

Empyema

Lung abscess

Question 6

What is acute bronchitis?

Answer 6

Inflam of medium sized airways

Mainly in smokers

Cough, fever, increased sputum prod, increased shortness of breath

CXR = normal

Question 7

What is chronic bronchitis?

Answer 7

Recurrent episodes of cough and shortness of breath

Not infective

Question 8

What is pneumonia?

Answer 8

= inflam of lung parenchyma = lung alveoli

Cause = bacterial, viral, apsiration

High mortality compared to upper

Presentation = fever, cough, pleuritic chest pain, shortness of breath , productive/dry cough

Abnormal CXR

Question 9

How can pneumonia be classified?

Answer 9

Clinical setting = community acquired, hospital acquired

Presentation = acute, chronic

MO = bacteria, viral, fungal

Pathology = lobar(complete lobe), brocho, interstitial

Question 10

Outline the pathophysiology of pneumonia

Answer 10

Acute inflam

Exudation of fibrin rich fluid

Neutrophil infiltration

Macrophage infiltration

Question 11

What typical MO cause community acquired pneumonia?

Answer 11

S. pneumoniae

H. influenzae

Question 12

What are the symptoms of community acquired pneumonia?

Answer 12

Shortness of breath 
Cough +/- sputum (yellow, rusty, current jelly) 
Fever
Rigors
Pleuritic chest pain
Malaise, nausea, vomiting

Question 13

Describe what is seen on examination of CAP?

Answer 13

Pyrexia

Tachycardia

Tachypnoea

Cyanosis

Dullness to percussion, tactile vocal fremitus = fluid means dullness

Bronchial breathing

Crackles

Question 14

Regarding CAP what investigations should be performed?

Answer 14

FBC
U+Es
CRP
ABG
CXR

Samples = sputum, broncho alveolar lavage, swabs, urine, serum

Question 15

What is the CURB-65 score?

Answer 15

Confusion, urea, respiration rate, BP, >65yrs

Guide you regarding management

Determine which Abx to use

Question 16

What are the possible outcomes from having pneumonia?

Answer 16

Resolution = organisation

Complications = lung abscess, bronchiectasis, empyema

Question 17

What is bronchiectasis?

Answer 17

Permanent enlargement of parts of the airways

Chronic cough and mucus prod

Question 18

What are the most common atypical organisms that cause pneumonia?

Answer 18

Mycoplasma

Legionella

Chlamydia

Coxiella

No cell wall = cell-wall active Abx don’t work

Question 19

Discuss viral pneumonia

Answer 19

Damage to cells lining the airways/alveoli

Fluid filled air spaces interferes with gas exchange

Cause = influenza, parainfluenza, adenovirus

Send nose/throat swab

Question 20

Discuss hospital acquired pneumonia

Answer 20

Acquired after 48hrs in hospital

MO = staph .A, enterobacteriaciae, pseudomonas sp, H influenzae

Treat = co-amoxiclav

Question 21

What is aspiration pneumonia?

Answer 21

Aspiration of exogenous material or endogenous secretions into the resp tract

Common in neurological dysphagia

Mixed infection = need broad spec Abx

Question 22

How can pneumonia be prevented?

Answer 22

Immunisation

Chemoprophylaxis – for pts with no spleen/dysfunction/immunodef

Smoking advice

Question 23

Which clinical features are used in the CURB-65 score?

Answer 23

confusion
urea
resp rate
BP
age >65 years

Question 24

What is the CURB-65 score?

Answer 24

estimates mortality of community-acquired pneumonia to help determine inpatient vs outpatient treatment