MindMap Gallery Hematology Pediatrics-Hematopoietic System Diseases
Hematology Pediatrics - A mind map of diseases of the hematopoietic system, which organizes the characteristics of hematopoiesis and blood images in children, an overview of childhood anemia, and knowledge about nutritional anemia. Come and take a look.
Edited at 2023-04-13 19:53:02El cáncer de pulmón es un tumor maligno que se origina en la mucosa bronquial o las glándulas de los pulmones. Es uno de los tumores malignos con mayor morbilidad y mortalidad y mayor amenaza para la salud y la vida humana.
La diabetes es una enfermedad crónica con hiperglucemia como signo principal. Es causada principalmente por una disminución en la secreción de insulina causada por una disfunción de las células de los islotes pancreáticos, o porque el cuerpo es insensible a la acción de la insulina (es decir, resistencia a la insulina), o ambas cosas. la glucosa en la sangre es ineficaz para ser utilizada y almacenada.
El sistema digestivo es uno de los nueve sistemas principales del cuerpo humano y es el principal responsable de la ingesta, digestión, absorción y excreción de los alimentos. Consta de dos partes principales: el tracto digestivo y las glándulas digestivas.
El cáncer de pulmón es un tumor maligno que se origina en la mucosa bronquial o las glándulas de los pulmones. Es uno de los tumores malignos con mayor morbilidad y mortalidad y mayor amenaza para la salud y la vida humana.
La diabetes es una enfermedad crónica con hiperglucemia como signo principal. Es causada principalmente por una disminución en la secreción de insulina causada por una disfunción de las células de los islotes pancreáticos, o porque el cuerpo es insensible a la acción de la insulina (es decir, resistencia a la insulina), o ambas cosas. la glucosa en la sangre es ineficaz para ser utilizada y almacenada.
El sistema digestivo es uno de los nueve sistemas principales del cuerpo humano y es el principal responsable de la ingesta, digestión, absorción y excreción de los alimentos. Consta de dos partes principales: el tracto digestivo y las glándulas digestivas.
Hematology Pediatrics-Hematopoietic System Diseases
Section 1 Hematopoiesis and hemogram characteristics in children
1. Hematopoietic characteristics
Hematopoiesis is the process of blood cell formation
(1) Hematopoiesis during embryonic stage
I mesodermal hematopoietic stage
Yolk sac hematopoiesis begins in the 3rd week of embryonic life
II liver and spleen hematopoietic stage
1) Starting from the 6th to 8th week of the embryo, active hematopoietic tissue appears in the liver and becomes the main hematopoietic site in the second trimester.
2) The spleen begins to form hematopoiesis around the 8th week of embryonic life
3) After the fetus is 5 months old, the function of red blood cells and granulocytes in the spleen gradually decreases, and it becomes a lifelong hematopoietic lymphoid organ by the time of birth.
4) Lymph nodes begin to produce lymphocytes from the 11th week of embryonic life. From then on, lymph nodes become organs that produce lymphocytes and plasma cells throughout life.
III bone marrow hematopoietic stage
Bone marrow begins to appear in the 6th week of embryonic life, but hematopoietic activity does not begin until the fetus is 4 months old, and quickly becomes the main hematopoietic organ, until it becomes the only hematopoietic site 2 to 5 weeks after birth.
(2) Hematopoiesis after birth
I bone marrow hematopoiesis
1) After birth, bone marrow mainly produces hematopoiesis
2) All bone marrow in infants and young children is red bone marrow; starting from 5 to 7 years old, adipose tissue (yellow marrow) gradually replaces hematopoietic tissue in long bones.
3) Yellow marrow still has potential hematopoietic function and can be converted into red marrow to restore hematopoietic function.
II extramarrow hematopoiesis
1) Causes: infection, anemia
2) The liver, spleen and lymph nodes are enlarged, and nucleated red blood cells or/and immature neutrophils may appear in the peripheral blood.
3) Infection and anemia will return to normal after being corrected
2. Blood characteristics
(1) Number of red blood cells and hemoglobin amount
1) The fetal period is in a relatively hypoxic state, and the synthesis of erythropoietin increases, so the number of red blood cells and the amount of hemoglobin are high.
2) Physiological anemia
reason
a With the establishment of spontaneous breathing after birth, blood oxygen content increases, erythropoietin decreases, bone marrow hematopoietic function temporarily decreases, and reticulocytes decrease
b Fetal red blood cells have a shorter lifespan and are more destroyed (physiological hemolysis)
c Factors such as rapid growth and development of infants, rapid increase in circulating blood volume, etc.
Features
a By 2 to 3 months old (earlier in premature infants), the red blood cell count drops to about 3.0×10^12/L, the hemoglobin count drops to about 100g/L, and mild anemia occurs.
b Physiological anemia is self-limiting and does not require treatment. After 3 months, the number of red blood cells and hemoglobin slowly increase, reaching adult levels at the age of 12 years.
(2) White blood cell count and classification
1) The classification of white blood cells is mainly the change in the ratio of neutrophils to lymphocytes
2) At birth, neutrophils account for about 0.65 and lymphocytes account for about 0.30; as the total number of white blood cells decreases, the proportion of neutrophils gradually decreases, and the two proportions are approximately equal 4 to 6 days after birth.
3) Lymphocytes account for about 0.60 and neutrophils account for about 0.35 at the age of 1 to 2 years. After that, the proportion of neutrophils gradually increases, and the two proportions are equal again at the age of 4 to 6 years.
(3) Platelet count
Basically the same as adults, 100×10^9~300×10^9/L
(4) Types of hemoglobin
(5) Blood volume
Children have larger blood volumes than adults
Section 2 Overview of anemia in children
【definition】
Anemia means that the number of red blood cells or hemoglobin per unit volume in peripheral blood is lower than normal
[Diagnostic Criteria for Anemia in Children]
[Classification of anemia]
I Classification by degree/Hb content
children
1) If the lower limit of normal is 90g/L, it is considered mild.
2) ~60g/L is moderate
3)~30g/L is severe
4) Those with <30g/L are extremely severe
Newborn: birth to 28 days
1) 144~120g/L is considered mild
2) ~90g/L is moderate
3)~60g/L is severe
4) Those with <60g/L are extremely severe
II Classification by cause
1) Insufficient production of red blood cells and hemoglobin
a Lack of hematopoietic substances
b Bone marrow hematopoietic dysfunction
c Infectious and inflammatory anemia
d Others: Anemia caused by chronic kidney disease, etc.
2) Hemolytic anemia
Abnormalities within red blood cells
a Structural defects in red blood cell membranes
b Red blood cell enzyme deficiency
c Abnormal hemoglobin synthesis or structure
Abnormalities outside red blood cells
a immune factors
b Non-immune factors: infection, antibodies, etc.
3) Hemorrhagic anemia
a Anemia caused by acute blood loss
b Anemia caused by chronic blood loss
III Classification by form
[Clinical manifestations]
I General performance
1) Pale skin and mucous membranes are prominent symptoms
2) Retardation of growth and development
II hematopoietic organ response
The liver, spleen and lymph nodes are enlarged, and nucleated red blood cells and immature granulocytes may appear in the peripheral blood.
Extramedullary hematopoiesis occurs
III Symptoms of each system
1) Circulatory and respiratory system
Accelerated breathing, increased heart rate, strengthened pulse, increased arterial pressure
2) Digestive system
Loss of appetite, nausea, bloating or constipation, etc.
3) Nervous system
Lack of energy, inability to concentrate, easily agitated, etc.
【Diagnostic Points】
I Medical history
1) Age of onset
2) Course of disease and accompanying symptoms
3) Feeding history
4) Past history
5) Family history
II Physical examination
1) Growth and development
2) Nutritional status
3) Skin and mucous membranes
4) Nails and hair
5) Enlargement of liver, spleen and lymph nodes
III Laboratory tests
1) Peripheral blood picture
2) Bone marrow examination
3) Hemoglobin analysis and examination
4) Red blood cell fragility test
5) Special inspection
【Treatment principles】
I Remove the cause
II General Treatment
IIIDrug therapy
IV red blood cell transfusion
Pay attention to volume and speed
V Hematopoietic stem cell transplantation
VI Treatment of Complications
Section 3 Nutritional anemia
1. Iron deficiency anemia
【Iron deficiency anemia (IDA)】
1) Anemia caused by lack of iron in the body leading to reduced hemoglobin synthesis
2) Clinical characteristics
a Microcytic hypochromic anemia
b Decreased serum ferritin
c Iron treatment is effective
3) Infants and young children have the highest incidence rate, seriously endangering children’s health
4) It is one of the common childhood diseases that is focused on prevention and treatment in my country.
【Metabolism of Iron】
I Content and distribution of iron in human body
1) The total iron content in the body of normal adult men is about 50mg/kg, that of women is about 35mg/kg, and that of newborns is about 75mg/kg.
2) About 64% of the total iron is used to synthesize hemoglobin, 32% is stored in the bone marrow, liver and spleen in the form of ferritin and hemosiderin, 3.2% is synthesized into myoglobin; <1% is present in iron-containing enzymes. and present in plasma in the form of transporting iron
II Sources of Iron
1) Exogenous iron
a mainly comes from food
b Animal food contains high iron content and is heme iron, which has high absorption rate
c The iron in food-based foods is non-heme iron and has low absorption rate
2) Endogenous iron
a Hemoglobin iron released by aging or destruction of red blood cells in the body
b accounts for 2/3 of human intake
c Almost all are reused
III Iron absorption and movement
1) Iron in food is mainly absorbed in the duodenum and upper jejunum in the form of Fe2
2) Fe2 entering the intestinal mucosal cells is oxidized into Fe3
3) Serum iron (SI)
Under normal circumstances, only 1/3 of transferrin in plasma is bound to iron, and this bound iron is called serum iron.
4) Unsaturated iron binding capacity
The remaining 2/3 of transferrin still has the ability to bind iron. Adding a certain amount of iron during in vitro experiments can make it reach a saturated state. The amount of iron added is the unsaturated iron binding capacity.
5) Serum total iron binding capacity (TIBC)
The sum of serum iron and unsaturated iron binding capacity
6) Transferrin saturation (TS)
Serum iron as a percentage of total iron binding capacity
IV Iron Utilization and Storage
1) Iron combines with protoporphyrin in mitochondria to form heme, and heme combines with globin to form hemoglobin.
2) Unused iron in the body is stored in the form of ferritin and hemosiderin
V Iron excretion
Under normal circumstances, only a very small amount of iron is excreted from the body every day.
VI iron requirements
1) 4 months to 3 years old need 1 mg/kg of iron per day
2) Premature infants need more iron, about 2mg/kg
VII Characteristics of Fetal and Childhood Iron Metabolism
1) Characteristics of iron metabolism during fetal period
a The fetus obtains iron from the mother through the placenta
b The highest amount of iron is obtained in the third trimester of pregnancy
c Immature children receive less iron from their mothers and are prone to iron deficiency.
2) Characteristics of iron metabolism in infants and young children
a After birth, more iron is released due to "physiological hemolysis", followed by relatively low hematopoiesis in the "physiological anemia" period. In addition, the iron obtained from the mother can generally meet the needs of 4 months, so the baby is not prone to deficiency in the early stage. iron
b Children aged 6 months to 2 years old have a high incidence of iron deficiency anemia
Iron obtained from the mother is gradually depleted
rapid growth and development
Active hematopoiesis
Both human milk and cow's milk, the staple food for infants, have low iron content and cannot meet the body's needs.
3) Characteristics of iron metabolism in childhood and adolescence
a The main reason for iron deficiency during this period is partial eclipse
b Chronic intestinal blood loss is also the cause of iron deficiency during this period
c. Iron loss caused by excessive menstruation in girls after menarche is also the cause of iron deficiency during this period.
【Cause】
I Congenital insufficient iron storage
The fetus obtains the most iron from the mother in the last 3 months of pregnancy
1) Premature birth, twins, multiple births, fetal blood loss
2) Low birth weight
3) The nutritional status of the pregnant mother is poor and she is severely iron deficient.
II Insufficient iron intake
1) Main causes of iron deficiency anemia
2) Milk, human milk, and cereals have low iron content, and complementary foods are not added in time
III growth and development factors
IV iron malabsorption
1) Unreasonable food combination
2) Chronic diarrhea
Excessive loss of V iron
a Long-term chronic blood loss
b Allergy
【Pathogenesis】
I Effects of iron deficiency on the blood system
1) During iron deficiency, heme production is insufficient, resulting in reduced hemoglobin synthesis.
2) Iron deficiency has little effect on cell division and proliferation, so the reduction in the number of red blood cells is not as obvious as that of hemoglobin, resulting in microcytic hypochromic anemia.
3) Three stages of anemia
a Iron reduction period (ID): The iron storage has been reduced, but the iron used for red blood cells to synthesize hemoglobin has not yet been reduced.
b Iron deficiency phase of erythropoiesis (IDE): The stored iron is further depleted, and the iron required for erythropoiesis is also insufficient, but the amount of circulating hemoglobin has not yet decreased.
c Iron deficiency anemia stage (IDA): Microcytic hypochromic anemia occurs
II Effects of iron deficiency on other systems
1) Affects the synthesis of myoglobin
2) Reduce the activity of various iron-containing enzymes
3) Iron deficiency causes cellular dysfunction, especially reduced activity of monoamine oxidase, causing important neuromediators (such as 5-HT, norepinephrine, etc.) to fail to function normally, manifesting as weakened physical strength, easy fatigue, and decreased attention. and mental retardation, etc.
4) Iron deficiency can also cause abnormalities in tissues and organs, such as abnormal keratosis of oral mucosa, anti-onychia, etc.
5) Iron deficiency can also cause reduced cellular immune function and susceptibility to infectious diseases.
[Clinical manifestations]
Most common between 6 months and 2 years old, onset is slow
I General performance
1) The skin and mucous membranes are pale, especially the lips, oral mucosa and nail beds.
2) Easily tired and not fond of activities
3) Dizziness, amaurosis, tinnitus, etc.
II Extramedullary hematopoietic manifestations
1) Mild enlargement of liver and spleen
2) The younger you are, the longer the course of the disease, the more severe the anemia, and the more obvious hepatosplenomegaly.
III Non-hematopoietic symptoms
1) Digestive system symptoms
Loss of appetite, pica
2) Nervous system symptoms
Irritability, memory loss, and intelligence often lower than that of children of the same age
3) Cardiovascular system symptoms
Increased heart rate, enlargement of the heart, and even heart failure in severe cases
4) Others
Reduced immune function, often combined with infection; anti-A, etc.
【Laboratory examination】
I Peripheral blood picture
1) The decrease in hemoglobin is more obvious than the decrease in the number of red blood cells, showing microcytic hypochromic anemia.
2) Peripheral blood smear shows that red blood cells vary in size, with mostly small cells, and the central light-stained area expands.
3) Red blood cells: MCV, MCH, MCHC are all reduced
4) The number of reticulocytes is normal or slightly reduced.
5) White blood cells and platelets generally remain unchanged
II bone marrow image
1) Actively proliferating
2) Mainly the proliferation of middle and late immature red blood cells
3) Granulocytes and megakaryocytes generally have no obvious abnormalities.
III Examination of Iron Metabolism
1) Serum ferritin (SF)
a can more sensitively reflect the iron storage situation in the body, and is therefore a sensitive indicator for diagnosing the iron deficiency phase (ID phase).
b <12μg/L indicates iron deficiency
2) Red blood cell free protoporphyrin (FEP)
a Decreased SF value and increased FEP without anemia, which are typical manifestations of the iron deficiency phase of erythropoiesis (IDE phase)
b FEP>0.9μmol/L (500μg/dl) indicates intracellular iron deficiency
3) Serum iron (SI), total iron binding capacity (TIBC), transferrin saturation (TS)
a reflects the iron content in plasma, and usually becomes abnormal during the iron deficiency anemia stage (IDA stage).
b SI decreases, TS decreases, TIBC increases
IV bone marrow stains iron
1) Bone marrow stainable iron is significantly reduced or even disappears
2) The extracellular iron in bone marrow cells is significantly reduced
3) Sideroblast count <15%
【diagnosis】
1) Medical history
2) Physical examination
3) Blood routine
Diagnose based on
1) Microcytic hypochromic anemia
2) Have clear causes and clinical manifestations of iron deficiency
3) Serum iron (SI) <8.95μmol/L
4) Transferrin saturation (TS) <15%
5) Red blood cell free protoporphyrin (FEP)/Hb is greater than 4.5ug/gHb
6) Serum ferritin (SF) <12μg/L
7) The external iron in the bone marrow disappears, the internal iron is <15% or disappears
8) Iron treatment is effective
【Differential Diagnosis】
1) Dysglobin anemia/thalassemia
2) Abnormal hemoglobinopathies
3) Vitamin B6 deficiency anemia, etc.
【treat】
The main principle is to remove the cause of the disease and supplement iron
I General treatment
1) Strengthen care and ensure adequate sleep
2) Avoid infection
3) People with severe anemia should pay attention to protecting heart function
II Remove the cause
1) Actively treat the primary disease
2) Adjust diet structure
3) Correct bad eating habits
III Iron therapy
1) Oral iron supplements
a Iron is a specific drug for treating iron deficiency anemia
b Ferrous iron salt preparations are clinically preferred because ferrous iron is easily absorbed
c Commonly used oral iron preparations include ferrous sulfate and ferrous glucose hydrochloride.
d Milk, tea, coffee and antacids can affect the absorption of iron at the same time as iron supplements
e To increase iron absorption, take vitamin C orally between meals.
f After hemoglobin returns to normal, continue taking iron supplements for 6 to 8 weeks to increase iron storage.
2) Iron injection
Iron injections are more likely to cause adverse reactions, so they should be used with caution
Commonly used iron supplements: sorbitol iron citrate complex, dextran iron complex, glucose iron oxide
Indications
a The diagnosis is confirmed, but there is no response to treatment after taking oral iron
b Those who have severe gastrointestinal reactions after oral administration and there is no improvement despite changing the type, dosage and administration time of the preparation.
c Those who cannot take oral iron or have poor absorption of oral iron after gastrointestinal surgery due to gastrointestinal disease
3) Observation on the efficacy of iron supplements
a After 12 to 24 hours of iron supplementation, the iron-containing enzyme in cells begins to recover, mental symptoms such as irritability are relieved, and appetite increases.
b Reticulocytes begin to rise 2 to 3 days after taking the medicine, reach a peak on 5 to 7 days, and drop to normal after 2 to 3 weeks.
c Hemoglobin gradually increases after 1 to 2 weeks of treatment, and usually reaches normality after 3 to 4 weeks of treatment.
d. After hemoglobin returns to normal, continue taking iron supplements for 6 to 8 weeks to increase iron storage.
IV red blood cell transfusion
1) Indications
a Severe anemia, especially those with heart failure
b Co-infected persons
c Those in urgent need of surgery
2) The more severe the anemia, the smaller the amount of each infusion should be
【prevention】
1) Promote breastfeeding
2) Provide good feeding guidance and promptly add supplementary foods that are rich in iron and have high iron absorption rates.
3) Infant and young children’s food should be fortified by adding an appropriate amount of iron.
4) For premature infants, especially premature infants with very low weight, it is advisable to provide iron prophylaxis starting from about 2 months of age.
2. Nutritional megaloblastic anemia
【concept】
1) Nutritional megaloblastic anemia is a type of macrocytic anemia caused by deficiency of vitamin B12 and/or folic acid.
2) Clinical characteristics
a Anemia, neuropsychiatric symptoms
b The cell body of red blood cells becomes larger
c Megaloblastic red blood cells appear in the bone marrow
d Effective treatment with vitamin B12 and/or folic acid
【Cause】
I Insufficient intake
1) Breastfeeding alone without adding complementary foods in time
2) Infants and young children with severe partial eclipse
3) Goat milk contains very low folic acid content
II Increased demand
1) Babies grow and develop quickly
2) People with severe infections have increased consumption of vitamin B12
III Absorption or metabolic disorders
1) Chronic diarrhea
2) Congenital folate metabolism disorder
【Pathogenesis】
1) When vitamin B12 or folic acid is lacking, tetrahydrofolate is reduced, resulting in reduced DNA synthesis
2) Insufficient DNA synthesis leads to disorders of granulocyte nuclear maturation
3) Vitamin B12 can promote the conversion of methylmalonic acid produced by fat metabolism into succinic acid and participate in the tricarboxylic acid cycle, thus maintaining the functional integrity of central and peripheral myelin nerve fibers.
3) Vitamin B12 deficiency mainly causes neuropsychiatric symptoms; folic acid deficiency mainly causes emotional changes
4) Vitamin B12 deficiency can weaken the bacterial killing effect of neutrophils and macrophages after engulfing bacteria, which is conducive to the growth of Mycobacterium tuberculosis. Therefore, people with vitamin B12 deficiency are prone to tuberculosis.
[Clinical manifestations]
It is more common between 6 months and 2 years old, and the onset is slow.
I General performance
1) Mostly puffy or mild facial edema
2) Sparse, yellow hair, etc.
II manifestations of anemia
1) The skin is often waxy yellow
2) Pale palpebral conjunctiva, lips, nails, etc.
3) Hepatosplenomegaly
III Neuropsychiatric symptoms
1) Symptoms such as restlessness and irritability occur
2) People with vitamin B12 deficiency show dull expression, unresponsiveness, and lethargy.
3) Intelligence and motor development are lagging behind or even regressing
4) Severe cases have convulsions, abnormal sensation, ataxia, and positive pathological reflexes
5) Folic acid deficiency does not cause neurological symptoms, but can lead to neuropsychiatric abnormalities.
IV digestive symptoms
Anorexia, nausea, vomiting, diarrhea, etc.
【Laboratory examination】
I Peripheral blood picture
1) Macrocytic anemia: MCV>94fl, MCH>32pg
2) The decrease in red blood cell count exceeds the decrease in hemoglobin
3) Decreased reticulocyte, white blood cell, and platelet counts
4) Neutrophils show excessive lobulation.
II bone marrow image
1) The proliferation is obviously active, mainly in the erythroid system.
2) Cytoplasmic vacuolation of neutrophils and excessive nuclear lobulation
3) The nuclei of megakaryocytes are excessively segmented, and the giant platelets
4) The phenomenon of old core and young pulp
III Serum vitamin B12 and folic acid determination
1) Vitamin B12<100ng/L is a deficiency
2) Serum folic acid <3μg/L is deficient
【diagnosis】
I Medical history
II Clinical Manifestations
III blood picture
IV bone marrow
V Vitamin B12 and folic acid determination
【treat】
I General treatment
1) Pay attention to nutrition and add complementary foods in time
2) Strengthen care and prevent infection
II Remove the cause
III Vitamin B12 and folic acid treatment
1) People with neuropsychiatric symptoms should be treated mainly with vitamin B12
2) Vitamin B12 500-1000 μg intramuscular injection once; or 100 μg intramuscular injection each time, 2-3 times a week, for several weeks until the clinical symptoms improve and the blood picture returns to normal
3) Vitamin B12 treatment response
a Megaloblastic erythrocytes in the bone marrow can transform into normal erythrocytes 6 to 7 hours after treatment
b General mental symptoms improve after 2 to 4 days
c Reticulocytes begin to increase in 2 to 4 days, reach a peak in 6 to 7 days, and return to normal after 2 weeks.
d Neuropsychiatric symptoms recover slowly
4) The oral dose of folic acid is 5 mg, 3 times a day, for several weeks until the clinical symptoms improve and the blood picture returns to normal.
5) Taking vitamin C orally at the same time helps the absorption of folic acid
6) Folic acid treatment response
a After taking folic acid for 1 to 2 days, the appetite improves and the megaloblastic red blood cells in the bone marrow return to normal.
b Reticulocytes increase on days 2 to 4 and reach a peak on days 4 to 7
c Red blood cells and hemoglobin return to normal in 2 to 6 weeks
【prevention】
1) Improve the nutrition of nursing mothers
2) Babies should add complementary foods in time and pay attention to a balanced diet
3) Treat intestinal diseases promptly
4) Pay attention to the rational use of anti-folate metabolism drugs (such as methotrexate)
Section 4 Hemolytic Anemia
Section 5 Bleeding Diseases
Section 6 Acute Leukemia
Section 7 Langerhans cell histiocytosis
Section 8 Hemophagocytic lymphohistiocytosis