(I) Disease knowledge
Our blood is red because the majority of red blood cells are red, and red blood cells are red because their main component is hemoglobin, which contains red iron ions and is therefore red. Therefore, iron is an important raw material for the synthesis of hemoglobin. If there is a lack of iron in the body, hemoglobin will not be synthesized enough, which will cause iron deficiency anemia.
Iron metabolism in our body works like this: normal people absorb about 1.0 to 1.5mg of iron from food every day, while about 20 to 25mg of iron is needed to make red blood cells every day, so most of the iron needed to make red blood cells comes from the aging and destroyed red blood cells in our body (endogenous iron). For exogenous (in food) iron, the absorption rate of iron in animal food is high, and the absorption rate of iron in plant food is low. Iron in food is mainly trivalent iron and must be reduced to divalent iron in an acidic environment or in the presence of reducing agents such as vitamin C to facilitate absorption. The duodenum and upper jejunum mucosa are the main sites of iron absorption. The amount of iron absorption is regulated by the body’s iron stores, if the body has more iron stores, the amount of absorption is less, and vice versa, the amount of absorption is more. Iron is bound to transferrin and transported to tissues or young red blood cells, and the iron transported to young red blood cells is involved in the formation of hemoglobin. The excess iron is stored in the form of ferritin and iron-containing heme in the mononuclear macrophage system in the liver, spleen, bone marrow and other organs, and is used when iron needs increase. The human body excretes no more than 1 mg of iron per day, mainly through the intestinal mucosa shedding cells with the feces, a small amount through urine, sweat, and breastfeeding women can also be excreted through breast milk.
All the conditions that lead to iron malabsorption, excessive loss and increased need can lead to iron deficiency anemia, mainly due to the following reasons.
1, malabsorption of iron due to poor dietary habits and gastrointestinal lesions: poor dietary habits such as strong tea and coffee can cause iron absorption disorders; after major gastrectomy, insufficient secretion of gastric acid and rapid entry of food into the jejunum, bypassing the main site of iron absorption (duodenum), which reduces iron absorption; gastrointestinal diseases caused by various reasons, such as chronic atrophic gastritis, Crohn’s disease and other inflammatory bowel diseases can Iron deficiency anemia can occur due to impaired iron absorption.
2. Excessive iron loss: Chronic blood loss caused by various reasons is the most common cause, mainly seen in excessive menstruation, gastrointestinal bleeding, hemoglobinuria, etc. Iron deficiency anemia is a very common disease in women of childbearing age, the majority of which is caused by excessive menstruation, often combined with uterine fibroids. Chronic gastrointestinal bleeding has become the main cause of iron deficiency anemia in men and postmenopausal women. The cause of bleeding can be benign diseases such as hemorrhoids, gastric and duodenal ulcers, esophageal hiatal hernia, gastrointestinal polyps, or malignant tumors of the gastrointestinal tract, so men and postmenopausal women suffering from iron deficiency anemia must be vigilant to exclude gastrointestinal tumors.
3. Insufficient iron intake and increased need are mainly seen in children during growth and development and in pregnant and lactating women.
Why does drinking strong tea and coffee often lead to iron deficiency anemia?
Excessive consumption of coffee and tea may lead to iron deficiency anemia. This is because the tannic acid in tea and polyphenols in coffee can form insoluble salts with iron and inhibit iron absorption; drinking strong tea after meals is more harmful because the essential iron and vitamins are usually taken in the daily diet, and after a full meal, the food is still in the stomach, so drinking strong tea at this time makes it easier for tannic acid to combine with iron and hinder iron absorption.
(B) Clinical manifestations
The function of hemoglobin is to be responsible for transporting oxygen, and hemoglobin transports oxygen to all parts of the body, then brings the carbon dioxide produced by the body back to the lungs, and then receives oxygen, and so on. Therefore, the clinical manifestations of insufficient hemoglobin synthesis caused by iron deficiency, i.e. iron deficiency anemia, are mainly the manifestations of tissue hypoxia: weakness, easy tiredness, dizziness, headache, blurred eyes, tinnitus, poor nausea, etc. in mild cases, and shortness of breath, palpitation or even heart failure, coma, accompanied by pallor and increased heart rate in moderate to severe cases. In addition to the clinical manifestations of hypoxia, iron deficiency in tissues can also lead to a decrease in the activity of intracellular iron-containing enzymes and iron-dependent enzymes, resulting in the following clinical manifestations: stomatitis, tongue inflammation, difficulty in swallowing or obstruction when swallowing, dry skin, lusterless hair, anthelmintic nails (finger and toe nails become flat or even concave and spoon shaped), etc.; abnormal mental behavior such as irritability, irritability, inattention, and even omnivory; susceptibility to infection. Children’s growth retardation, mental retardation, etc.
(iii) Diagnosis and treatment
1. Diagnosis: The hematologist will first determine whether anemia exists according to the patient’s symptoms and clinical manifestations, and then observe whether the red blood cell index is consistent with the characteristics of small cells and low pigmentation according to routine blood tests (because of the low hemoglobin content of red blood cells in patients with iron deficiency anemia, the red blood cells are “small” and “light” in color. “If the patient’s serum ferritin decreases, serum iron decreases and total iron binding capacity increases, the diagnosis of iron deficiency anemia can be confirmed. the diagnosis of iron deficiency anemia. If necessary, bone marrow examination and bone marrow iron staining can also be done to assist in the diagnosis. The effectiveness of experimental iron therapy is also a diagnostic method. After the diagnosis is confirmed, the cause of iron deficiency must be investigated, especially for elderly men or postmenopausal women once the manifestation of iron deficiency anemia appears, the cause must be traced, especially excluding gastrointestinal tumors.
2. Treatment.
Once the diagnosis of iron deficiency anemia is confirmed, iron supplementation treatment can be started.
Commonly used oral iron supplements include: ferrous succinate (Sulforaphane, 35% iron), 0.1g each time, 3 times/day; other ferrous sulfate (20% iron); ferrous fumarate (33% iron); iron polysaccharide complex (Liguaneng, 46% iron), etc. Iron should be selected for its high iron content, easy absorption and low gastrointestinal reaction. Reticulocytes start to rise in 5-10 days after oral administration of iron, and reach a peak in 7-12 days, after which they start to decline, and hemoglobin starts to rise after 2 weeks, with an average recovery of 2 months.
Injectable iron such as iron dextrose can be used for deep intramuscular injection when there are.
(i) there are severe GI reactions such as nausea, vomiting, abdominal pain, etc., which cannot be tolerated with oral iron.
(ii) There is an obvious absorption disorder in the digestive tract, making oral iron unabsorbable.
(iii) The presence of serious gastrointestinal diseases, which are aggravated by taking iron.
④Those who are in urgent need of raising hemoglobin during late pregnancy, before surgery, or when there is a high blood loss. It should be emphasized that the application of injectable iron must be based on the formula to calculate the patient’s “iron deficiency”, and then give the corresponding supplement as needed to avoid damage to the body due to excessive iron deposition in the body caused by excessive supplementation.
(iv) Etiological treatment and prevention.
Only when the cause of iron deficiency anemia is cured can iron deficiency anemia be cured from the root by combined iron supplementation. Those with insufficient dietary intake should have a balanced diet and avoid strong tea and coffee. Meat is the best source of iron. Vegetable fiber, phosphate, bran, and acidophilus can combine with iron and reduce iron absorption, while vitamin C can increase iron absorption. Iron supplements can be taken appropriately during the rapid growth period and pregnancy. For women of childbearing age, please ask gynecology to solve the problem of excessive menstrual bleeding is the key; while for elderly men or postmenopausal women with digestive tract tumors, removal of tumors is the key.
【Features of iron deficiency anemia in the elderly】.
Iron deficiency anemia is the most common type of geriatric anemia, which can account for 20~50%. In the diagnosis, we should first pay attention to the presence of obvious or insidious chronic blood loss. Among the chronic blood loss in the gastrointestinal tract, bleeding from gastric and duodenal ulcer disease and hemorrhoids are more common, however, gastric and colon tumors should be carefully excluded. Older women may lose blood due to gynecologic tumors. Iron deficiency anemia in the elderly can also be caused by gastric acid deficiency or malnutrition and can respond well to treatment with iron, but it must also be considered that iron deficiency is often accompanied by vitamin B12 and folic acid deficiency, so combination therapy is advisable.
Foods with high iron content and aiding iron absorption
(1) Iron-rich animal foods include lean animal meat, blood (blood tofu), liver, kidney, tongue, etc., as well as duck gizzard, squid, jellyfish, shrimp, egg yolk, etc.; plant foods include sesame, kelp, black fungus, nori, hairy vegetables, shiitake mushrooms, soybeans, black beans, bean curd, red curd, celery, shepherd’s purse, dates, sunflower seeds, walnuts, etc.
(2) Eat more foods rich in vitamin C, such as fresh green leafy vegetables and fruits, to promote the absorption of iron in the intestine.
(3) Be aware that vegetable fiber can affect the absorption of iron, so iron supplementation is best from animal sources.