This is an updated guideline on the management of iron deficiency anaemia in adults from the British Society of Gastroenterology (BSG). It was first published in 2011 and was last updated in 2021.
Over the last two years (2021-3), the use of FIT has been updated significantly. There is now a lot of evidence to show that FIT is useful in the investigation of IDA. In our area (Wessex), ALL patients with IDA, regardless of their age are advised to have FIT done. Patients over the age of 60 with any anaemia (regardless of iron status) are advised to have FIT done.
What is new in this IDA guideline?
The basics of this guideline on iron deficiency anaemia (IDA) aren’t going to change our management. There is more detail on capsule endoscopy and when it should be used as this has become more prevalent. Here are some of the bits I found particularly useful:
- IDIOM App. This is a useful website. You can put in a patient’s age, sex, Hb and MCV and it will give you a risk score for whether they are likely to have significant pathology. There are certain presumptions made in this, so you need to read the info before using the risk score.
- Functional iron deficiency. This wasn’t something I was really aware of, but is a useful concept. I will explain more below, but basically it is where a patient has enough iron, but can’t use it.
- Don’t use a FIT in the investigation of IDA. There is currently not enough evidence to support their use in IDA.
- Where a patient is anaemic, but has equivocal iron studies, you can try oral iron replacement therapy (IRT). A response of an increased Hb of ≥ 10g/L within 2w is suggestive of iron deficiency.
- Oral IRT should start with OD dosing. This is as effective as more frequent dosing and has fewer side-effects. If OD dosing isn’t tolerated, try alternate day dosing, which may be just as effective.
- Parenteral iron treatment. There are some really useful criteria for when to refer for parenteral iron. I have detailed these below.
- Ferric maltol. This is a relatively new iron formulation. It contains 30mg elemental iron (most OTC preparations have 14mg and ferrous fumarate would have 69mg). It is useful if patients can’t tolerate oral IRT. It is expensive, but much cheaper than parenteral iron.
- Check the response to oral iron after 2w if possible (Hb should increase by ≥ 10g/L). If you can’t check at 2w, check at 28d (Hb should increase by ≥ 20g/L). It is important to assess response early in case the patient needs an alternative form of replacement.
- Flowcharts. There are some useful flowcharts in the guideline, though they don’t have huge amounts of detail in. There is a good table listing all the causes of IDA (table 1) and another with the various oral IRT options (table 3) which is very helpful.
- Vitamin C does not help absorption of iron from the diet, or reduce the side-effects from taking iron. We therefore shouldn’t be advising that patients take vitamin C alongside oral iron replacement therapy.
- New for 2023: Don’t use a FIT in the investigation of IDA. There is currently not enough evidence to support their use in IDA.