【Key points】Diagnosis of iron deficiency anemia!

Iron deficiency can be divided into three stages:

Iron storage deficiency Iron deficiency erythropoiesis (iron deficiency) Iron deficiency anemia
.

(1) Absolute reduction of iron, that is, low iron reserves in the body
.

(2) Reduced functionality, decreased function of phagocytes and reticuloendothelial cells to release iron, resulting in relative iron deficiency
.

1.
Domestic diagnostic criteria for iron deficiency anemia (meet any 2 or more of the following Articles 1 and 2~9 to diagnose iron deficiency anemia):

(1) Small cell hypochromic anemia:

Hb< 120 g/L in males and 110 g/L in females with < erythrocyte morphology;

(2) There are clear causes and clinical manifestations of iron deficiency;

(3) Serum ferritin< 14 μg/L;

(4) Serum iron < 8.
95 μmol/L, total iron binding capacity > 64.
44 μmol/L;

(5) Ferritin saturation < 0.
15;

(6) Bone marrow iron staining showed that bone marrow granules could be dyed with iron and disappeared, and sideroblasts < 15%;

(7) Red blood cell free protoporphyrin (FEP) > 0.
9 μmol/L (whole blood), blood zinc protoporphyrin (ZEP) > 0.
9 μmol/L (whole blood), or FEP/Hb> 4.
5 μg/g Hb;

(8) serum soluble ferritin receptor (sTRF) concentration> 26.
5 nmol/L (2.
25 mg/L);

(9) Iron treatment is effective
.

2.
Interpretation of diagnostic criteria for iron deficiency anemia:

(1) Regular project inspection:

The mean red blood cell volume and mean red blood cell hemoglobin content were significantly reduced
.

(2) Iron metabolism index:

Serum ferritin levels (<14 micrograms/L) are the most sensitive and specific indicator for identifying iron deficiency and accurately reflect decreased
iron stores.

Transferrin synthesis increases, transferrin saturation decreases (<15%), transferrin saturation decreases in patients with anemia of chronic disease (ACD), and ferritin levels increase, mainly due to impaired iron release within macrophages, and serum soluble transferrin receptor levels increase
in iron deficiency.

Bone marrow iron staining is a reliable method for assessing iron stores in macrophages and nucleated red blood cells, but its use is limited
by its invasive testing.

With ACD and iron deficiency anemia, transferrin saturation decreases, and ferritin levels are defined as <100 micrograms/L
.

In heart failure with iron deficiency anaemia, ferritin levels < 300 micrograms/L
.

In IR iron deficiency anemia, transferrin saturation is low, but serum ferritin levels are normal or low (Figure 1).

3.
Etiological diagnosis of iron deficiency / iron deficiency anemia:

Patients with iron deficiency anemia should look for a cause;

Non-invasive tests such as urea breath test or anti-Helicobacter pylori antibodies, gastrointestinal tests;

Women with vaginal bleeding should have a gynecological examination;

C-reactive protein is associated with inflammatory/neoplastic diseases in the elderly;

Multiple factors, including clonal hematopoiesis, should be excluded;

Patients with suspected IR iron deficiency anemia should have TMPRSS6 gene sequencing
.