Management of Iron Deficiency Anemia in Adults: A List of Recommended Points from the BSG Guidelines!

Guide

Iron deficiency anemia (IDA) is a kind of anemia due to the lack of iron in the body, resulting in a reduction in hemoglobin (Hb) synthesis, it is mainly manifested as weakness, fatigue and lack of endurance, may appear dizziness during exercise, shortness of breath performance, daily usually appear inattention, irritability, pale skin, and even pica performance, severe may lead to rapid heartbeat, difficulty swallowing, muscle soreness during exercise, nails will unconsciously become brittle and appear flattened or sunken, such as untimely treatment, Permanent intellectual and behavioral problems
may arise.

The 2021 guidelines for the management of IDA in adults published by the British Society of Gastroenterology (BSG) elaborate on the diagnosis, differentiation and treatment options for IDA
.

background

1.
IDA is common and is the leading cause of disease worldwide (quality of evidence: high; Consensus level: 100%; Declaration intensity: strong).

2.
IDA can be caused by a range of gastrointestinal lesions (including cancer), so urgent gastrointestinal testing should be considered in adults with a new diagnosis of IDA without obvious cause (quality of evidence: high; Consensus level: 85%; Declaration intensity: strong).

definition

3.
It is recommended that anaemia be defined as Hb concentrations below the lower normal values of the relevant population and laboratory tests (quality of evidence: moderate; Consensus level: 100%; Declaration intensity: strong).

• The WHO defines anemia as having an Hb concentration of less than 130 g/L in men over 15 years of age, less than 120 g/L in non-pregnant women over 15 years of age, and less than 110 g/L
  in women in the second and third trimesters.
  It is reasonable to use the lower limit of normal values for laboratory tests to define anemia, but it should be consistent
  with the lower limit defined by the WHO.
  

4.
It is recommended to confirm iron deficiency through iron studies prior to investigation, serum ferritin is the only most useful marker of IDA, but if ferritin is suspected, other blood tests (such as transferrin measurement) may be helpful (quality of evidence: moderate; Consensus level: 92%; Declaration intensity: strong).

5.
Guidelines recommend that good feedback from patients with anaemia on iron therapy (elevated Hb ≥10 g/L) over a 2-week period is highly suggestive of absolute iron deficiency, even if the results of iron deficiency studies are ambiguous (quality of evidence: moderate; Consensus level: 100%; Declaration intensity: strong).

Initial clinical evaluation

6.
A detailed history is recommended, as these may provide critical information on the etiology of individual IDA cases (quality of evidence: low; Consensus level: 100%; Declaration intensity: strong).

7.
It is recommended that urinalysis, urine microscopy, celiac disease (CD) screening and, where appropriate, endoscopy of the upper and lower gastrointestinal tracts (quality of evidence: high; Consensus level: 85%; Declaration intensity: strong).

8.
3%-5% of IDA patients have CD, patients are advised to have regular serological examinations, or small bowel biopsy on gastroscopy (quality of evidence: high; Consensus level: 84%; Declaration intensity: strong).

9.
Age, sex, Hb concentration, and mean cell volume are all independent predictors of gastrointestinal cancer risk in IDA and need to be considered as part of the
overall risk assessment.
It can be seen that patients with iron deficiency but not anaemia have a lower risk of cancer (quality of evidence: high; Consensus level: 92%; Declaration intensity: strong).

10.
There is currently insufficient evidence that stool immunochemical testing can be used for risk stratification
in IDA patients.
However, this part of the evidence base is rapidly evolving, on the basis of which this guidance may change as a result (quality of evidence: low; Consensus level: 100%; Declaration intensity: weak).

11.
It is recommended that gastroscopy and colonoscopy should generally be used as the first line of gastrointestinal examination in newly diagnosed IDA men and postmenopausal women
.
In patients who are not candidates for colonoscopy, CT colonography is another reasonable option (quality of evidence: moderate; Consensus level: 100%; Declaration intensity: strong).

Recurrent IDA and follow-up of IDA

12.
Most IDA patients normalize Hb levels through iron replacement therapy (IRT), but a small number of IDAs are found to recur at long-term follow-up (quality of evidence: low; Consensus level: 92%; Declaration intensity: strong).

Further evaluation of the small intestine

13.
Further testing of the small intestine and renal tract is recommended for patients with acceptable bidirectional endoscopy negative and inadequate response to IRT or recurrence of IDA recommended to exclude other causes (quality of evidence: moderate; Consensus level: 85%; Declaration intensity: strong).

14.
Because capsule endoscopy is highly sensitive to mucosal lesions, capsule endoscopy is recommended to examine the small intestine
of patients with IDA.
CT/MR enterographic may be considered in patients who are not candidates for capsule endoscopy, which is a complementary test to evaluate inflammation and neoplastic diseases of the small intestine (quality of evidence: high; Consensus level: 100%; Declaration intensity: strong).

15.
After negative endoscopy of a qualified capsule, it is recommended that further gastrointestinal tests should be considered only if there is still IDA after IRT (quality of evidence: high; Consensus level: 100%; Declaration intensity: strong).

16.
Long-term IRT may be an appropriate strategy when the cause of recurrent IDA is unknown or irreversible (quality of evidence: low; Consensus level: 100%; Declaration intensity: strong).

Treatment of IDA

17.
It is recommended that IRT should not be postponed while waiting for IDA examination unless colonoscopy is imminent (quality of evidence: high; Consensus level: 100%; Declaration intensity: strong).

18.
It is recommended that patients with IDA should be given one tablet of ferrous sulfate, ferrous fumarate, or gluconate
per day for initial treatment.
If the patient is intolerant, the dose taken every other day should be taken at a dose of one tablet, or treatment with alternative oral preparations or parenteral iron (quality of evidence: moderate; Consensus level: 92%; Declaration intensity: strong).

19.
When treating symptomatic IDA, limited transfusion of concentrated red blood cells may sometimes be required, in which case IRT is still required after transfusion (quality of evidence: high; Consensus level: 100%; Declaration intensity: strong).

20.
It is recommended that patients should strictly observe the response to Hb for the first 4 weeks of oral iron, and that treatment with oral iron should be continued until about 3 months after the normalization of Hb levels to ensure adequate iron reserves in the bone marrow (quality of evidence: medium; Consensus level: 92%; Declaration intensity: strong).

21.
When oral iron is prohibited, ineffective or intolerable, it is recommended to consider parenteral iron
.
If it is determined that oral IRT is unlikely to be effective and / or requires urgent correction of IDA, the use of parenteral iron should be considered at an early stage (quality of evidence: high; Consensus level: 92%; Declaration intensity: strong).

22.
Unless additional indications are present, there is insufficient evidence to support invasive testing for non-anaemic iron deficiency, but regular monitoring of blood counts is recommended (quality of evidence: low; Consensus level: 92%; Declaration intensity: weak).

After restoring Hb and iron stocks by IRT, it is recommended to monitor blood counts regularly (initially possibly every 6 months) to detect recurrent IDA (quality of evidence: low; Consensus level: 85%; Declaration intensity: strong).

Special case - young women

24.
IDA is common in young women, and the main contributing factors include decreased menstruation, pregnancy, and too little dietary intake (quality of evidence: moderate; Consensus level: 92%; Declaration intensity: strong).

25.
Underlying gastrointestinal lesions are not common in young women with IDA, so after screening for CDs, it is recommended that further studies be required only if there are additional clinical features of concern (quality of evidence: moderate; Consensus level: 92%; Declaration intensity: strong).

26.
If it is deemed necessary to perform gastrointestinal examinations of pregnant women before delivery, gastroscopy and magnetic resonance enterography (post-trimester) are safe during pregnancy (quality of evidence: low; Consensus level: 91%; Declaration intensity: strong).

Special case - young men

27.
IDA is not common in young men, but once confirmed, it is recommended to guarantee the same research algorithm as in older patients (quality of evidence: high; Consensus level: 100%; Declaration intensity: strong).

Special case - elderly

28.
Iron deficiency is common in older people and is usually caused by multifactorial etiology (quality of evidence: high; Consensus level: 100%; Declaration intensity: strong).

29.
It is recommended that patients with severe comorbidities and/or limited physical status carefully consider the risks and benefits of invasive endoscopy and alternative testing (quality of evidence: moderate; Consensus level: 92%; Declaration intensity: strong).

Special cases - special comorbidities

30.
Functional iron deficiency (FID) is a common contributing factor to advanced chronic kidney disease (CKD)-related anemia (quality of evidence: high; Consensus level: 92%; Declaration intensity: strong).

31.
Iron deficiency is common in chronic heart failure (CHF) and is usually caused by multiple factors (quality of evidence: high; Consensus level: 92%; Declaration intensity: strong).

32.
Parenteral IRT improves symptoms and quality of life in patients with CHF with FID (quality of evidence: moderate; Consensus level: 100%; Declaration intensity: strong).

33.
In the management of iron deficiency associated with CKD or CHF, it is recommended that appropriate reference be made to appropriate reference to appropriate and professional guidelines referred to in the guidelines issued by experts (quality of evidence: moderate; Consensus level: 92%; Declaration intensity: strong).

34.
IDA is a common manifestation of inflammatory bowel disease (IBD), particularly when the disease is active (quality of evidence: high; Consensus level: 100%; Declaration intensity: strong).

Intolerance and malabsorption of oral IRT may be a particular problem in IBD-related IDA therapy, and patients may need to receive parenteral IRT (quality of evidence: moderate; Consensus level: 100%; Declaration intensity: strong).

Special case - gastrointestinal surgery

36.
IDA is common after gastric and/or small bowel resection or bypass surgery, including bariatric surgery (quality of evidence: high; Consensus level: 92%; Declaration intensity: strong).

37.
In the new report of IDA, it is recommended that patients with a history of gastrointestinal or bariatric surgery should not rule out other reasons for looking for IDA (quality of evidence: low; Consensus level: 85%; Declaration intensity: strong).

Service Considerations

38.
It is recommended that all healthcare providers should provide a clear reference and management pathway for IDA patients (quality of evidence: low; Consensus level: 100%; Declaration intensity: strong).

39.
To ensure the efficient use of resources, it is recommended that a designated team led by a senior clinician provide an IDA management pathway (quality of evidence: low; Consensus level: 100%; Declaration intensity: strong).

40.
It is recommended that healthcare providers should work towards a mobile care base for the administration of parenteral iron therapy (quality of evidence: low; Consensus level: 100%; Declaration intensity: strong).

British Society of Gastrology guidelines for the management of iron deficiency anaemia in adults[J].
Gut.
2021 Sep 8:gutjnl-2021-325210.
doi:10.
1136/gutjnl-2021-325210.