This is a new guideline from NICE on when to prescribe antibiotics in an acute exacerbation. It was published in Dec 18. It should be read alongside their updated guideline on COPD.
The most interesting bit for me about this new guideline was that only 50% of COPD exacerbations are thought to be caused by bacterial infections. The rest are caused mainly by viral infections or smoking. Unfortunately there is no good evidence on what signs or symptoms we can use to differentiate between a bacterial and non-bacterial exacerbation.
Another change is that all antibiotic courses are now advised to be five days only.
One fact that really surprised me is that the NNT with antibiotics in the community to avoid 1 treatment failure is 14 - much higher than I would have guessed.
What should you consider before choosing an antibiotic?
- Previous sputum culture results.
- Possible resistance after multiple courses of antibiotics.
What should you consider when you get a sputum result?
NICE advises that you only need to change the antibiotic if
- the bacteria are resistant and
- the patient's symptoms are not already improving.
What advice should you give a patient when prescribing antibiotics?
Their symptoms may not completely resolve after the course of antibiotics.
They should seek medical advice if their symptoms worsen significantly or rapidly, or if they become systemically very unwell, or if they aren't improving within 2-3 days (or some other agreed time).
What advice should you give a patient if you are not prescribing antibiotics?
Why it is not needed.
That they should seek medical attention immediately if:
- symptoms (like sputum colour or thickness or volume) worsen rapidly or significantly.
- symptoms do not start to improve within an agreed time frame.
- they become systemically very unwell.
What antibiotic should you choose?
This is obviously NICE's advice, but you may wish to consult local microbiology advice too.
1st line: Amoxicillin, doxycycline or clarithromycin - all for 5 days. NB - if the patient is on prophylactic antibiotics, use an antibiotic from a different class.
2nd line: an alternative 1st line antibiotic if they are not improving within 2-3 days or other agreed time frame.
Alternative choices: when there is a higher risk of treatment failure (see below). This should be guided by previous susceptibilities where possible.
- Co-amoxiclav 5 days.
- Levofloxacin 5 days (beware recent MHRA guidance).
- Co-trimoxazole 5 days (only use this when there is evidence of susceptibility and when there is a good reason to prefer this combination to a single antibiotic).
Why only a 5 day course of antibiotics?
The evidence suggests that a 5 day course is as effective as longer courses.
When is there a higher risk of treatment failure (prompting an alternative choice of antibiotic)?
- Repeated courses of antibiotics.
- Previous or current sputum culture showing a resistant strain.
- People at higher risk of complications.
Should we use back-up antibiotics?
It is not advised in this guideline. There have not been any studies done on whether they are effective or safe.
What is the evidence behind the use of antibiotics in COPD?
The evidence isn't really that great. Most of the studies have been small and used heterogenous groups of people, making it hard to apply the results to normal practice.
The following are the NNT (numbers needed to treat) to avoid 1 treatment failure (i.e. no improvement of symptoms):
- In the community - NNT 14.
- In hospital - NNT 10.
- In ITU - NNT 3.