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Hereditary hemolytic anemia (primary)
Erythrocytopathy. The most common is hereditary familial spherocytosis (microspherocytosis, Minkowski-Shoffar disease, protein-dependent membrane disease).
The disease is inherited in an autosomal dominant way. The basis of its development is a defect in the structure of the erythrocyte membrane, which leads to a change in their shape from discoid to spherical. Such red blood cells do not deform and, when passing through narrow capillaries, lose part of the membrane substance, decrease in size, and are destroyed. Their membrane becomes highly permeable to sodium ions and water. More energy (glucose, ATP) is spent on sodium removal than normal. In blood, where there is enough glucose, the sodium pump eliminates excess sodium. In the intersinus spaces of the spleen, where the glucose content is reduced, sodium is not excreted, which leads to osmotic hemolysis of red blood cells. The main clinical manifestations of the disease are periodic hemolytic crises, anemia, jaundice, splenomegaly, urobilinemia, urobilinuria, fever, trophic ulcers of the lower leg as a result of microthrombosis.
In this case, the content of Hb and red blood cells decreases, normochromia, microspherocytosis, reticulocytosis (10% or more) develops, and the osmotic resistance of red blood cells decreases. During hemolytic crises, neutrophilic leukocytosis is observed.
Hereditary erythrocytopathies (membranopathies) also include ovalocytosis (elliptocytosis), stomatocytosis, acanthocytosis and other GA, which derive their name from their inherent characteristic form of red blood cells (see above).
Enzymatopathies (enzymopathies) unite a group of HA, which are manifested by a lack of activity of red blood cell enzymes involved in the process of their energy supply. In countries adjacent to the Mediterranean Sea, Latin America, Africa, and Asia, anemia is often encountered due to a deficiency in the activity of glucose-6-phosphate dehydrogenase (G-6-FDG) red blood cells. There are two main mutant forms of this enzyme. One of them (form B) is common among Europeans, the other (form A) - among the black population of Africa. The disease is transmitted by the codominant type, linked to the X chromosome. The gene responsible for the production of erythrocyte G-6-ADH is located on the X chromosome next to the color vision gene and hemophilia gene. Persons suffering from G-6-FDH deficiency of erythrocytes, as well as those with sickle cell anemia, are less likely to die from tropical malaria, which causes the prevalence of this pathology in the "malaria" regions. An early manifestation is characteristic of the disease, often during the neonatal period. It can be combined with hemophilia and color blindness and is clinically manifested mainly in men. In women, a bright clinic is possible only if they have homozygosity for this gene.
With insufficient G-6-FDH activity in red blood cells, aerobic oxidation of glucose is disrupted, which weakens the formation of reduced NADP and the restoration of glutathione, which is necessary to protect Hb and the erythrocyte membrane from oxidizing agents, including drugs. When taking conventional therapeutic doses of drugs - oxidizing agents (antimalarial drugs, sulfonamides, derivatives of salicylic acid, etc.), Нb is oxidized, heme disappears from its molecule, and the globin chain precipitates in the form of Heinz bodies. Red blood cells are released from them in the spleen. At the same time, part of their membrane substance is lost, as a result of which they undergo hemolysis, a hemolytic crisis develops, which stops after all red blood cells with a deficiency of G-6-FDG are destroyed (the phenomenon of "self-limitation" of hemolysis). A similar pattern is also observed when horse beans are taken with food (favism - “Baghdad spring fever”, common in Iraq during the flowering of legumes), sometimes with viral infections, hypovitaminosis P, C, E, poisoning with aniline, benzene, phenylhydrazine, as a result intake with food in large quantities of blueberries, blueberries, inhaling pollen of herbs, trees, etc. (the disease occurs in Belarus).
Hemolytic crises are characterized by high fever, headache, adynamia, hemoglobinuria, jaundice, hepatomegaly. These phenomena are caused by inflammatory mediators that are released upon damage to red blood cells, including pyrogenic cytokines.
The blood picture shows: Нb - 20-40 g / l, erythrocytes up to 1x1012 / l, reticulocytosis, red blood cells with Heinz bodies, anisocytosis, poikilocytosis, dehmacytes, schizocytes, basophilic puncture of erythrocytes, normoblastosis, neutrophilic leukocytosis (leukocytosis) .
Hemoglobinopathies (hemoglobinoses) occur as a result of hereditary disorders of globin synthesis. They can be qualitative, due to a change in the primary structure of Hb (sickle cell anemia), and quantitative, due to a violation of the rate of synthesis of one of the globin chains (thalassemia). Most hemoglobinopathies are inherited autosomally dominantly. This pathology is found mainly in countries of a hot climate: in Central Africa, Asia, and Cuba. In some areas of Central Africa, the carriage of the sickle cell anemia gene reaches 40-45%. Homozygous carriage gives high infant mortality.
Sickle cell anemia (hemoglobinopathy S, drepanocytosis) is the most common form of pathology associated with an abnormality of the Hb structure. It is common in many tropical regions of Africa, where malaria is endemic. This pathology occurs when in the b-chain of Нb the glutamine amino acid is replaced by valine, which leads to a change in the physicochemical properties of the hemoglobin molecule (HbS). In the reduced state, the solubility of HbS decreases sharply, the molecules aggregate, and as a result, gel and crystals form. The polymers appearing in this case are long strands grouped into so-called tactoids. The latter change the shape of the red blood cell, as a result of which sickle-shaped red blood cells (drepanocytes) are formed, which are easily subjected to hemolysis.
In drepanocytes, malarial plasmodia die. The cause of their death is a decrease in the potassium concentration that occurs in the red blood cell in the state of HbS deoxygenation due to damage to the plasma membrane and physical damage to parasites by Hb aggregates.
Clinically, a disease manifests itself if the content of HbS in red blood cells exceeds 45% or less, but when the patient enters a condition of reduced partial oxygen pressure (high altitude, high-altitude flight, etc.). In this case, hemolytic, aplastic, polyuric, nocturic, acute pain, occlusive crises periodically occur. They are provoked by hypoxia and acidosis of any origin. Pain attacks are associated with aggregation of drepanocytes in the bloodstream, the formation of microemboli, vascular microthrombosis with the development of heart attacks of various organs, strokes, "chest syndrome" (occlusion of the branches of the pulmonary artery), ischemia and retinal detachment. Chronic hypoxia and impaired blood flow lead to myocardial hyperfunction and congestive heart failure. Patients have secondary immunodeficiency, increased susceptibility to infections, especially in childhood.
The blood picture of this disease is characterized by anemia with a significant decrease in the number of red blood cells and Hb, hypo- or normochromia, anisocytosis, poikilocytosis, basophilic puncture of red blood cells, the presence of drepanocytes, reticulocytosis, sometimes normoblastosis, during hemolytic crisis - neutrophilic leukocytosis with a shift to the left.
Thalassemia (Cooley disease, Mediterranean anemia) unites a group of hereditary anemias in which the presence of a mutant gene leads to inhibition of the synthesis of globin chains, deficiency of HbA.
Distinguish between a- and b-thalassemia. More common b-thalassemia, in which the synthesis of b-chains of globin is absent or reduced. In this case, the amount of HbA decreases, which consists of two a- and b-chains, and the content of HbA2 (two a- and g-chains) and HbF (two a- and Ay-chains) increases. Excessively synthesized a-chains form unstable Нb, its precipitates arise, their red blood cells are removed by cells of the macrophage-phagocytic system. In this case, the erythrocyte membrane is damaged, the extra a-chains interacting with the SH-groups of this membrane, increase its permeability, which also contributes to an increase in hemolysis of red blood cells. Violated heme synthesis and iron metabolism.
Homozygotes develop severe hemolytic anemia (large thalassemia, Cooley disease), leading to high infant mortality at the 1st or 5th-8th year of life. The “Mongoloid” type of face is characteristic, pallor and yellowness of the skin, ulcers on the lower extremities, splenomegaly, lag in growth and development; X-ray in patients revealed the skull of a "hedgehog" (acicular periosteum of the parietal and frontal bones).
Heterozygotes for thalassemia genes are characterized by increased resistance to malaria (erythrocytes with a shorter lifespan previously undergo phagocytosis, in which plasmodium dies). This form of b-thalassemia is much easier than other forms.
In violation of the synthesis of a-chains, a-thalassemia occurs. Homozygous carriage leads to fetal death, heterozygous - to hemolytic anemia of varying severity.
The blood picture shows hypochromic anemia (CP = 0.5 - 0.4), anisocytosis, microcytosis, poikilocytosis, hypochromia, a large number of target erythrocytes (torocytes), basophilic puncture of red blood cells; reticulocytosis (5-10%), moderate neutrophilic leukocytosis with a shift to the left, an increase in the level of serum iron. There is a double heterozygous carriage of abnormal allelic (structural) and non-allelic (structural and regulatory) genes, which leads to severe hemolytic anemia. For example, abnormal НbЕ and b-thalassemia, НbS / b-thalassemia, НbН / a-thalassemia, etc. Close relatives of people with a high level of carriage of abnormal hemoglobins can lead to an increase in the number of homozygotes and double heterozygotes.
The distribution of hemoglobinosis coincides with the so-called malaria zones of the Earth. It turned out that carriers of HbS and patients with thalassemia either do not suffer from tropical malaria, or tolerate it in a mild form. The resistance of hemoglobinosis patients to malaria is explained by the fact that its causative agents are intracellular (intraerythrocytic) parasites. They consume a large amount of oxygen, thereby provoking accelerated hemolysis of red blood cells, during which they themselves die. Since asymptomatic HbS carriage or small forms of thalassemia do not cause serious harm to the body, it can be said that one less severe pathology (mild forms of hemoglobinosis) becomes a protective factor in relation to another more serious disease (malaria).
Acquired hemolytic anemia occurs with the appearance of autoantibodies to the body's own red blood cells (autoimmune); exposure to isoimmune antibodies (transfusion of incompatible blood, hemolytic disease of the newborn); medicinal substances (sulfonamides, etc.); mechanical damage to red blood cells (prosthetics of heart valves, marching hemoglobinuria, etc.); viral infections, the effects of chemical and physical factors (lead salts, snake venoms, burns, ultraviolet radiation, etc.).
The hemolysis of red blood cells in this form of anemia is due to metabolic and structural damage to their membranes, a subsequent increase in the osmolarity of the intracellular contents, a decrease in the ability of red blood cells to deform in the sinuses of the spleen, which contributes to their destruction.
In the blood picture in the first hours of the development of anemia, short-term “false” hyperchromia is noted, then normochromic or hypochromic anemia, reticulocytosis, polychromatophilia, leukocytosis, an increase in the blood content of indirect bilirubin develop.
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Hereditary hemolytic anemia (primary)
- Hereditary hemolytic anemia due to impaired activity of red blood cell enzymes
Enzymatopathies or non-spherocytic hemolytic anemias are characterized by a hereditary decrease in the activity or instability of red blood cell enzymes. Inherited autosomal recessive or X-linked recessive type. The most severe hemolytic manifestations are observed, as a rule, in homozygous carriers with an almost complete absence of enzyme activity in
- CONGENITAL HEMOLITIC ANEMIA CONDITIONED BY GENETIC (HEREDITARY-FAMILY) FACTORS
CONGENITAL HEMOLYTIC ANEMIA CONDITIONED BY GENETIC (HEREDITARY-FAMILY)
- ACUTE HEMOLITIC ANEMIA CONDITIONED BY EXOGENOUS HEMOLYTIC FACTORS
Acute hemolytic processes accompanied by severe anemia and jaundice occur when poisoning with hemolytic poisons of organic and inorganic origin (snake venom, fungal poison, saponins, arsenic hydrogen, phosphorus, phenylhydrazine), with severe burns or in connection with septic, streptococcal or anaerobic infections . To hemolytic anemia of an infectious nature
- HEREDITARY HEMOLITIC ANEMIA
The following groups of hereditary hemolytic anemia are distinguished: 1. Due to a violation of the structure of the erythrocyte membrane. 2. Associated with impaired activity of red blood cell enzymes. 3. Associated with a violation of the structure or synthesis of hemoglobin. Hereditary hemolytic anemia due to a violation of the erythrocyte membrane Hereditary hemolytic anemia associated with
- HEMOLYTIC ANEMIA CAUSED BY DISTURBANCE OF HEMOGLOBIN SYNTHESIS
This group of hemolytic anemia includes two main subgroups: • thalassemia - hereditary hemolytic anemia due to impaired synthesis of one or more globin polypeptide chains (“quantitative” hemoglobinopathies); • hemoglobinopathies - hereditary hemolytic anemia caused by a change in the primary structure of the globin polypeptide chains, which leads to
- HEMOLITIC ANEMIA CONDITIONED BY CHEMICAL, BIOLOGICAL AND PHYSICAL FACTORS
Hemolytic anemia due to infectious agents Hemolytic anemia can develop with malaria, bartonellosis, clostridial sepsis, bacterial septicemia, cholera, salmonellosis, coli infection, and others. Malaria is an acute, chronic or recurring vector-borne infectious disease that is accompanied by four malaria
- Hereditary hemolytic anemia associated with a violation of the membrane of red blood cells (membranopathy)
Membranopathies are characterized by a hereditary defect in the structure of the membrane protein or a violation of the lipids of the erythrocyte membrane. Inherited autosomal dominant or augosomal recessive. Hemolysis is usually localized intracellularly, that is, the destruction of red blood cells occurs mainly in the spleen, to a lesser extent in the liver. Classification of hemolytic anemia associated
- Hereditary hemolytic anemia.
Distinguish the terms of hemoglobinopathy and hemoglobinosis. Under hemoglobinopathies understand any violations in the structure of hemoglobin. Those of them that are accompanied by the development of anemia are called hemoglobinosis. HEMOGLOBINOSIS - a group of diseases that is heterogeneous in nature, a characteristic feature of which is the presence of abnormal hemoglobin due to a violation of the structure or
- Hereditary hemolytic anemia associated with impaired structure or synthesis of hemoglobin (hemoglobinopathies)
Hemoglobinopathies are hereditary abnormalities in the synthesis of human hemoglobins, manifested either by changes in the primary structure of the hemoglobin molecule (“qualitative” hemoglobinopathies), or a violation of the ratio or lack of synthesis of one of the globin chains with an unchanged primary structure (“quantitative” hemoglobinopathies). Hemoglobinopathies are inherited autosomally dominantly,
- Hereditary hemolytic anemia
- ACQUIRED HEMOLITIC ANEMIA
Acquired hemolytic anemia includes: • immune hemolytic anemia; • medicinal hemolytic anemia; • traumatic and microangiopathic hemolytic anemia; • anemia due to the influence of hemolytic poisons, chemicals, bacterial toxins; • paroxysmal night
- HEMOLITIC ANEMIA
Hemolytic anemia includes an extensive group of anemic conditions that occur when blood destruction processes prevail over hematopoiesis. Клиническая картина гемолитической анемии весьма вариабильна и зависит как от характера гемолитического агента и длительности его воздействия на организм, так и от степени компенсации гемолитического процесса. Classification.
- Гемолитические анемии
Гемолитические анемии составляют обширную группу анемических состояний различной этиологии, общим признаком которой является патологически повышенное разрушение эритроцитов. Известно, что средняя продолжительность жизни эритроцитов не превышает 100—120 дней. Гемолитической анемии свойственно укорочение продолжительности жизни эритроцитов. Гемолиз может происходить внутриклеточно или же
- ГЕМОЛИТИЧЕСКИЕ АНЕМИИ
Общим признаком гемолитических анемий является усиленное разрушение эритроцитов, обуславливающее с одной стороны анемию и повышенное образование продуктов распада, с другой - реактивно усилинный эритропоэз. Увеличение продуктов распада эритроцитов клинически проявляется желтухой лимонного оттенка, повышенным содержанием в крови несвязанного ( неконъюгированного ) билирубина, при его
- Приобретенные гемолитические анемии
Это гетерогенная группа гемолитических анемий, возникающих под влиянием целого ряда факторов, обладающих способностью повреждать эритроциты и вызывать преждевременное их разрушение. Классификация приобретенных гемолитических анемий [Идельсон Л. И., 1975] I. Гемолитические анемии, связанные с воздействием антител. 1. Изоиммунные гемолитические анемии 1) гемолитическая болезнь новорожденных
- ГЕМОЛИТИЧЕСКИЕ АНЕМИИ У ДЕТЕЙ
Гемолитические анемии - группа анемий, характеризующихся синдромом гемолиза - повышенным разрушением эритроцитов. Эритроциты живут около 120 дней, затем они разрушаются - фагоцитируются макрофагами, преимущественно селезенки. При гемолитической анемии продолжительность жизни эритроцитов значительно укорочена, а при её сокращении ниже 30 дней появляется клиника гемолитического
- Гемолитические анемии (ГА)
Группа анемий, наследственно обусловленных (40 %) или приобретенных (60 %), общим признаком которых является укорочение жизни эритроцитов. При этом имеет место стойкое (хроническая ГА) или массированное (острая ГА) преобладание разрушения эритроцитов над их образованием. Проявляется заболевание синдромами усиленного гемолиза и компенсаторного усиления эритропоэза. Усиление гемолиза
- Гемолитические анемии
Удельный вес гемолитических анемий (ГА) среди других заболеваний крови составляет 5,3 %, а среди анемических состояний — 11,5 %. В структуре гемолитических анемий преобладают наследственные формы заболеваний. Гемолитические анемии представляют собой группу заболеваний, наиболее характерным для которых является повышенное разрушение эритроцитов, обусловленное сокращением продолжительности их
- ИММУННЫЕ ГЕМОЛИТИЧЕСКИЕ АНЕМИИ
Л. И. Идельсон (1979) выделяет следующие варианты иммунных гемолитических анемий: • изоиммунные гемолитические анемии - связаны с изоантителами против групповых факторов эритроцитов. Этот вариант анемии развивается тогда, когда антитела к эритроцитам попадают в организм плода из крови матери (гемолитическая болезнь плода или новорожденного), а также при переливании эритроцитов, несовместимых