Fever and a cough: pneumonia

Question 1

what is the microbial difference between bronchitis and pneumonia

Answer 1

bronchitis is VIRAL

pneumonia commonly caused by strep. pneumoniae bacteria, can be fatal

Question 2

What are some of the clinical features that can distinguish bronchitis from pneumonia

Answer 2

Listen to the lungs for changes in breath sounds
Inc child can watch the breathing pattern and if they have bad pneumonia, the side of the chest which has pneumonia won’t move as much as the other side
Ask: have you found yourself getting short of breath easily
Percussion for dullness
put hands on their lungs and get them to speak, in healthy person/ lung will feel solid vibrations
If all the sings add together to make pneumonia dint need to do a chest X ray.

Question 3

Sings of pneumonia in the elderly

Answer 3

RR- 69%
Crackles - 80% 
Consolation - 30% 
Fevers / chills - 50% 
non-pulmonary (delirium, falls) - 20% 
Pneumonia is a systemic illness particularly in the elderly, bronchitis is not

Question 4

What does pneumonia look like on a X ray

Answer 4

generally white consolidation, usually confined to a lobe, may need to do lateral film to check behind the heart

Question 5

What are the risk factors for pneumonia?

Answer 5

age <2 or >65
Chronicling disease
Smoking
Immune dysfunction

Question 6

What sort of germs cause pneumonia

Answer 6

strep pneumoniae 
mycoplasma pneumoniae 
Legionella 
Stap. aureus 
Couple of other rare ones
Will only be a able to diagnose the bacteria type in about half of the cases

Question 7

Type of bacteria that is streptococcus pneumoniae

Answer 7

alpha-haemolytic - (so it can partially haemolyse red blood cells )streptococcus
Viridian group related to s. mitts
Colonises nasopharynx
5-10% of adults, 20-40% of children
prevalence of colonisation increases in winter in adults colonisation persists for a few weeks

Question 8

Pneumococcal surface protein A (PspA)

Answer 8

binds to epithelial cells and also prevents deposition of C3b

Question 9

PpC

Answer 9

prevents activation of complement cascade

Question 10

Chlorine biding protein

Answer 10

binds to immunoglobulin receptor on epithelial cells, allows transport into cell

Question 11

pneumolysin (toxin)

Answer 11

lyses neutrophils and epithelial cells

Question 12

polysaccharide capsule

Answer 12

prevents phagocytosis and complement opsonisation

Question 13

pili

Answer 13

contibute to colonisation and cytokine production (TNFalpha) during invasion

Question 14

reasonably healthy individuals with pneumonia thats not super serious can generally be on oral antibiotics at home and just rest?

Answer 14

yessss

Question 15

in the pre antibiotic era, most people with mild pneumonia?

Answer 15

actually got better

Question 16

what is the primary investigative test for pneumonia?

Answer 16

CXR, if normal, antibiotics aren’t required

Question 17

Sputum culture?

Answer 17

yield dependant on quality of sample - only if admitted

Question 18

Nasopharyngeal swab

Answer 18

if admitted, Viral PCR if positive stop antibiotics

Question 19

Blood cultures

Answer 19

if admitted, yield low

Question 20

Urine ICT

Answer 20

if admitted, moderate yield for S. pneumoniae lower for legionella

Question 21

serology

Answer 21

acute and convalescent for antibodies against mycoplasma . chlamydia and legionella

Question 22

antibiotic treatment

Answer 22

required

reduces duration of illness and risk of death

Question 23

antibiotics and S.pneumoniae

• penicillin resistance
• Oral vs IV dosing

Answer 23

• mediated by altered PBP/transpeeptidase which reduces penicillin binding affinity
• IV dosing more accurate

Question 24

Macrolides

Answer 24

Can be used when those who are allergic to penicillin get pneumonia
Board spectrum
Limited activity against gram negative bacteria - reduced permeability of cell membrane
Active against streptococci, staphylococci and other causes of pneumonia used in skin infection if allergic to penicillin drugs
treatment of chlamydia: azithryomycin as single dose

Question 25

Adverse effects of Macrolide antimicrobials

Answer 25

GIT upset - erythromycin antagonist of motolin receptor int he gut, it increases peristalsis  
Sudden death - class effect 
Drug-drug interactions