pneumonia

Question 1

what is the definition of pneumonia?

Answer 1

inflammation of the lung characterised by exudation into the alveoli

• classified anatomically - lobar/segmental/lobular

Question 2

what is the most common bacterial cause of pneumonia worldwide?

Answer 2

streptococcus pneumoniae

Question 3

how does an infection reach the lungs?

Answer 3

microaspiration - inspiring small amounts of a bug

hematogenous = spread from distal infected side

macroaspiration = inhalation of gastric contents etc.

Question 4

what effect does streptococcus pneumoniae and neisseria meningitidis have on secretory IgA?

Answer 4

they produce proteases that can split the secretory IgA

= virulence factor

Question 5

what are the 5 most common pathogens to cause peumonia ?

Answer 5

Streptococcus pneumoniae is the most frequently isolated pathogen.

Relative to other pathogens, respiratory viruses, Mycoplasma pneumoniae, Legionella spp, Chlamydophila (formerly Chlamydia) pneumoniae, and Haemophilus influenzae are also common.

Question 6

what is the most common viral cause of pneumonia?

Answer 6

influenza A and B

other recognized viral pathogens include RSV (respiratory syncytial virus), parainfluenza virus and adenovirus, metapneumovirus, varicella and severe acute respiratory syndrome

Question 7

what sort of clinical signs do we see in patients with pneumonia?

Answer 7

• reduced expansion
• increased vocal fremitus
• dull percussion
• bronchial breath sounds
• medium/late/paninspiratory crackles
• pleural rub

Question 8

what are the typical/atypical agents of pneumonia?

Answer 8

“Typical”organisms include S. pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Group A streptococci, Moraxella catarrhalis, anaerobes, and aerobic gram-negative bacteria.

“Atypical”refers to pneumonia caused by Legionella spp, Mycoplasma pneumoniae, C pneumoniae, and C. psittaci.

Question 9

is there a clinical sign that might distinguish the pneumonia causing agent?

Answer 9

no - you MUST use laboratory findings

Question 10

in what patients do we commonly see S. aureus pneumonia?

Answer 10

usually seen in elderly, and younger patients whoa re recovering from influenza (psotinfluenza pneumonia). However, the pneumococcus remians the most frequent pathogen in this setting

Question 11

what tests do you need to perform on someone with suspected pneumonia ?

Answer 11

• oxygenation saturations and where necessary, ABG
• chest radiograph to allow diagnosis
• urea and electrolytes to inform severity
• CRP to aid in diagnosis/baseline measure
• FBC
• LFT

Question 12

how do we assess pneumonia?

Answer 12

CURB65 score

C= confusion (8 or less on AMT score)

U= urea (raised >7mmol.L)

R= resp. rate (raised)

B= Blood pressure ( low, <90 systolic)

A=age (>65 years)

Question 13

What CURB65 score warrants hospital admission?

Answer 13

3-4

(consider at 1-2)

Question 14

what antibiotic do we generally use for aspiration pneumonia?

Answer 14

amoxicillin remains the preferred agent at a dose of 500mg

if there is a penicillin allergy

doxycycline or clarithromycin are appropriate as alternatives

Question 15

what is the general managment for pneumonia?

Answer 15

• oxygen - maintain pressure O2 (safe if not COPD patient)
• IV fluids if volume depleted
• VTE propholaxis
• nutritional support
• early mobility
• chest physiotherapy
• compression stalkings