renal anemia in children
Introduction
Introduction to pediatric renal anemia Renal anemia refers to anemia caused by various factors such as insufficient production of erythropoietin (EPO) or toxic substances in uremic plasma that interfere with the production and metabolism of red blood cells, although recent research progress has revealed that kidneys and red blood cells are closely formed. Related, but there is still some debate about the mechanism of renal anemia. At present, it is generally believed that the occurrence of renal anemia is caused by a combination of multiple factors. In severe kidney disease, when azotemia occurs, anemia is combined. The degree of anemia is related to azotemia. Generally, when the glomerular filtration rate is reduced to 25% to 30% of normal, anemia begins to appear. basic knowledge The proportion of illness: 0.003% Susceptible people: children Mode of infection: non-infectious Complications: dizziness, heart failure
Cause
Causes of renal anemia in children
Causes:
Due to a decrease in renal failure to erythropoietin, the presence of erythropoiesis-producing substances and shortened red blood cell life in uremic plasma.
Pathogenesis:
The production of erythropoietin is reduced in chronic renal dysfunction. A large number of tests have shown that in patients with renal dysfunction, the erythropoietin in the plasma can only maintain the normal low limit and the renal function is normal. The erythropoietin in the plasma of patients with anemia is significantly elevated, and the degree of erythropoietin reduction is parallel with renal excretion dysfunction. When erythropoietin is severely deficient, the bone marrow has a compensatory ability to lose hemolysis due to hemolysis and anemia. 10% of erythropoietin is produced by the liver, so even if there is still a small amount of erythropoietin in the plasma of the double nephrectomy, it is also proved that uremic plasma has an inhibitory effect on erythroid progenitor cells.
Therefore, it is currently believed that the bone marrow of patients with uremia loses the compensatory function of anemia, which is related to the decrease of erythropoietin and the presence of erythroid inhibitory substances in the plasma of such patients. In addition to myeloproliferative disorders, shortening the life span of red blood cells is also the cause of anemia. If the normal human red blood cells are lost to uremic patients, the normal red blood cell life is also shortened. Conversely, the red blood cells of uremic patients are exported to normal people, and the red blood cells have normal lifespan. It has not yet been proved which specific toxins can cause this. Hemolysis of patients, hemodialysis and peritoneal dialysis can not alleviate this kind of hemolysis, uremia can lead to abnormal platelet function, secondary gastrointestinal and urinary tract blood loss, in addition to blood dialysis can also lose a small amount of red blood cells Anemia, there are still iron absorption disorders, or reduced intake of iron and folic acid due to anorexia, leading to anemia.
Prevention
Pediatric renal anemia prevention
Mainly to do a good job in health education, parents should recognize the danger of the disease to children and the importance of prevention. Specific measures should include health guidance for pregnant mothers, reasonable feeding after birth, and emphasize the timely addition of complementary foods containing more iron, especially animal foods, such as various red meats and livers, to treat digestive diseases and nutrition. Adverse and infectious diseases, early prevention of iron in preterm infants and twin fetuses, and attention to the supply of nutrients to children in the recovery period.
Actively prevent and cure various primary causes of CRF, such as chronic nephritis, pyelonephritis, etc.; those who have developed kidney damage need to actively prevent infection, control high blood pressure, avoid nephrotoxic drugs, etc., while paying attention to reasonable diet and rest, Effectively prevent the progress of the disease and promote the recovery of the disease.
Complication
Pediatric renal anemia complications Complications, dizziness, heart failure
Severe anemia can be complicated by heart enlargement and palpitations, dizziness and so on. Mainly for various complications caused by chronic renal failure, in addition to anemia, such as hypertension, heart failure, cardiomyopathy, water, electrolyte disorders and acid-base imbalance, renal bone disease, fractures, infections. When children have anemia, they can cry, worry, and even affect mental development.
Symptom
Pediatric anemia symptoms common symptoms dizziness
In general, patients with serum creatinine levels greater than 308 mol / l (3.5 mg / dl) can be associated with anemia, the degree of anemia between individuals can be significantly different, but each individual has a more stable degree of anemia, polycystic kidney Anemia in patients with aging is lighter than other causes of anemia caused by renal failure. Similarly, renal failure with hypertension, hematocrit is higher than normal blood pressure, which may be caused by hypertension, renal ischemia, and stimulation of residual nephron More EPO is produced. In addition, the degree of anemia associated with nephrotic syndrome is more severe than that of patients without nephrotic syndrome. This may be due to a large amount of protein loss, resulting in a decrease in EPO, transferrin and essential amino acids, and clinical symptoms of renal failure anemia. It is lighter than other kinds of anemia. This may be due to the increase of 2,3-DPG in the red blood cells of the kidney, which reduces the affinity of hemoglobin and oxygen in the cells, making oxygen more easily enter the tissues from the blood and improving the hypoxic state.
Examine
Examination of renal anemia in children
The degree of anemia varies, mostly moderate to severe anemia, mostly positive color, reticulocytes are normal or reduced, blood smears can be seen in varying degrees of zigzag, broken shapes in the shape of helmets and triangles, white blood cells are normal or increased, Platelet normal or decreased, bleeding time and blood clot contraction is not normal, clotting time is normal, capillary fragility test can be positive, bone marrow hyperplasia is normal, grain/red ratio increases, serum iron and total iron binding capacity are often reduced, bone marrow iron staining is normal The plasma ferritin is increased, and the capillary fragility test can be positive. Chest radiography, B-ultrasound and electrocardiogram should be performed. Other kidney disease needs to be selected.
Diagnosis
Diagnosis and diagnosis of renal anemia in children
diagnosis
According to kidney disease and renal failure and anemia, the characteristics of laboratory tests were confirmed.
Differential diagnosis
Different from anemia caused by other causes, there are kidney disease manifestations and other complications caused by renal failure, and the results of laboratory tests are easy to identify.
Clinically, the classification of pathogenesis and causes of anemia is often:
(a) erythropoiesis-reducing anemia
Abnormalities in hematopoietic cells, bone marrow hematopoietic microenvironment, and hematopoietic materials affect erythropoiesis, which can reduce erythropoiesis-deficient anemia.
1. Anemia caused by abnormal hematopoietic stem cells
(1) aplastic anemia (AA): AA is a bone marrow hematopoietic failure associated with primary and secondary hematopoietic stem cell damage. The pathogenesis of partial pancytopenia is related to the production of anti-myeloid autoantibodies by B cells, which in turn destroy or inhibit bone marrow hematopoietic cells.
(2) pure red cell anemia (PRCA): PRCA refers to the damage of bone marrow erythroid hematopoietic stem and progenitor cells, which in turn causes anemia. According to the cause, the disease can be divided into two categories: congenital and acquired. Congenital PRCA, the Diamond-Blackfan syndrome, is caused by heredity; acquired PRCA includes both primary and secondary. Some scholars have found that some patients with primary PRCA have their own EPO or young red blood cell antibodies in their serum. Secondary PRCA mainly has drug-related, infection-related types (bacteria and viruses, such as parvovirus B19, hepatitis virus, etc.), autoimmune disease-related types, lymphoproliferative disease-related types (such as thymoma, lymphoma, plasma). Cytopathic and lymphocytic leukemia, etc.) and acute aplastic crisis.
(3) congenital erythrocytic anemia (congenital dyserythropoieticanemia, CDA): CDA is a type of hereditary erythroid stem progenitor cells caused by abnormal clonal abnormalities, refractory anemia characterized by erythroid ineffective hematopoiesis and morphological abnormalities . According to hereditary methods, the disease can be divided into autosomal concealed hereditary and dominant hereditary.
(4) Hematopoietic malignant clonal diseases: These diseases have abnormalities in hematopoietic stem and progenitor cells, including myelodysplastic syndromes and various hematopoietic neoplastic diseases such as leukemia. The former is due to pathological hematopoiesis, hyperproliferation, high apoptosis, and in situ hemolysis; the latter has tumoric hyperplasia, low apoptosis and poor differentiation, and hematopoietic regulation is also affected, thereby reducing normal mature red blood cells and causing anemia.
2. Anemia caused by abnormalities in hematopoietic microenvironment: The hematopoietic microenvironment includes bone marrow stroma, stromal cells and cytokines.
(1) Anemia caused by damage of bone marrow stroma and stromal cells: bone marrow necrosis, myelofibrosis, myelosclerosis, marble disease, bone marrow metastasis of various extramedullary neoplastic diseases, and various infections or non-infectious osteomyelitis The hematopoietic microenvironment may be abnormal due to damage to the bone marrow stroma and stromal cells, which may affect blood cell formation.
(2) Anemia caused by abnormal levels of hematopoietic regulatory factors: stem cell factor (SCF), interleukin (IL), granule-mono-column colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G- CSF), erythropoietin (EPO), thrombopoietin (TPO), platelet growth factor (TGF), tumor necrosis factor (TNF) and interferon (IFN) all have positive and negative regulation of hematopoiesis. Insufficient EPO due to renal insufficiency, liver disease, and pituitary or hypothyroidism; neoplastic diseases or certain viral infections can induce more hematopoietic negative regulators such as TNF, IFN, inflammatory factors, etc., can lead to chronic disease Anemia of chronic disease (ACD).
3. Anemia caused by insufficient hematopoietic raw materials or utilization disorders: Hematopoietic raw materials refer to substances necessary for proliferation, differentiation and metabolism of hematopoietic cells, such as proteins, lipids, vitamins (folic acid, vitamin B12, etc.), trace elements (iron, copper, Zinc, etc.). Any deficiency or utilization of hematopoietic materials may result in reduced erythropoiesis.
(1) Anemia caused by deficiency of folic acid or vitamin B12 or utilization disorder: megaloblastic anemia caused by absolute or relative deficiency or utilization of folic acid or vitamin B12 due to various physiological or pathological factors.
(2) Iron deficiency and iron utilization of anemia: This is the most common anemia in the clinic. Iron deficiency and iron utilization disorders affect heme synthesis, and this type of anemia is called hemoglobin synthesis abnormal anemia. The erythrocyte morphology of this type of anemia is small, and the central light-stained area is enlarged, belonging to small cell hypochromic anemia.
(2) hemolytic anemia (HA), that is, red blood cells destroy excessive anemia
(3) Hemorrhagic anemia
According to the rate of blood loss, acute and chronic, chronic hemorrhagic anemia often combined with iron deficiency anemia. Can be divided into coagulopathy (such as idiopathic thrombocytopenic purpura, hemophilia and severe liver disease) and non-clotting diseases (such as trauma, tumors, tuberculosis, bronchiectasis, peptic ulcer, sputum and Two types of gynecological diseases, etc.).
