STUDY - Technical - New Dacian's Medicine
Anemia
(3)
Translation Draft
Let's move on to addressing the diagnosis of anemia! Evaluation of anaemia, whether a primary haematological disorder or secondary to another disease, is common in medical practice, the success of this assessment depends not only on the knowledge and understanding of the doctor but also on the speed and skill with which it is achieved. As a general rule, significant anaemia should be assessed without delay, using a battery of laboratory tests, to obtain clear information about the erythropoietic anomaly. This will avoid misinterpretation of a test due to changes in the patient's clinical status.
For example, the diagnosis of a nutritional anemia will be prevented if the patient changes his diet or receives vitamins or mineral supplements. A pre-test blood transfusion will alter the measurement of the production of erythrocytes required for diagnosis by reducing the response to erythropoietin. It is important not to assume a diagnostic relationship before the paraclinical examination. Even if the etiology of anaemia is suggested by the clinical picture, a full laboratory evaluation is essential. Anemias are the result of several associated factors and not of one.
The first step in diagnosing anaemia is its initial classification, taking into account the functional defect of erythropoiesis (if there is a failure in the production of erythrocytes, an abnormality in the maturation of precursors or an increase in erythrolysis). In a patient with moderate to severe anaemia, the reticulocytic index and HLG are sufficient to make a distinction. Thus, a defect in the production of erythrocytes (hypoproliferative anemia) will be characterized by a low reticulocytic index and a small or no change in the morphology of erythrocytes, this being a normochrome, normocytic anemia.
The maturation disorder also has a low reticulocytic index, but is accompanied by a morphology of either microcytic or macrocytic. Increased erythrocytosis secondary to hemolysis or hemorrhage typically leads to increased reticulocyte index to levels three times higher than normal. The morphology of erythrocytes depends on the specific type of condition. VEM is usually normal or slightly elevated, depending on the level of reticulocytosis. Examination of the smear may reveal characteristic cellular forms, which can help in the development of the specific diagnosis. Classification of anaemia according to the functional defect is helpful in choosing the laboratory tests to be carried out next.
Most anemias encountered in medical practice are hypoproliferative ones, they appear as a result of insufficient response of the medullary production of erythrocytes to the degree of anemia. They can result from bone marrow damage, iron deficiency or insufficient erythropoietin secretory response to anemia. The last cause may reflect inhibition of the release of erythropoietin by inflammatory cytokines, low metabolic needs or permanent loss of peritubular interstitial cells in the final stages of a kidney disease.
Laboratory tests to help differentiate these defects include iron deposit assessment and bone marrow examination. Patients with anaemia due to this acute or chronic inflammation have characteristic values of serum iron, CTLF and serum ferritin. The same goes for iron losses leading to iron deficiency. Primary deficiency in the proliferation of precursors, due to a medullary lesion caused by a drug, a leukaemia alteration or a tumor infiltration, can usually be diagnosed by examining the morphology of the bone marrow.
Maturation defects of erythrocytic precursors are initially recognized by the association of a low reticulocyte index with a distinct change in cellular morphology. Patients have either macrocytic anaemia (VEM greater than 100 fl) or microcytic anaemia (VEM less than 80 fl). The low erythrocytic production index reflects the insufficiency of erythropoiesis caused by altered precursor maturation. Examination of medullary morphology will indicate an increase in the E/G ratio at levels greater than 1:1, which confirms the proliferation of the erythroid marrow. The reason for the poor maturation of precursors may be obvious. A defect in nuclear maturation, which causes macrocytic anaemia, will be accompanied by a megaloblastic morphology of the bone marrow. Patients with maturation defects of the cytoplasm will experience a decrease in hemoglobin load of more mature erythrocytic precursors.
Severe iron deficiency and inherited defects in the synthesis of globin chains (thalasemias) cause moderate to severe hypochroma, microcytic anaemia. These disorders can be easily differentiated based on the morphology of the blood smear and the racial origin of the patient. If this is not possible, the evaluation of iron reserves will help in the development of the diagnosis. Anomalies inherited or acquired in mitochondrial function can lead to either microcytic or macrocytic anaemia. Based on the detection of ringed sideroblasts on the colored medullary smear, they are first classified as sideroblastic anemias.
And in this case, the evaluation of iron reserves is important for differential diagnosis and patient approach. Nuclear maturation defects are due to folic acid or vitamin B12 deficiency, exposure to a chemotherapy agent and a myelodisplastic or preleukemic condition. Regarding the differential diagnosis of cytoplasmic defects, medullary morphology and evaluation of iron reserves are useful in differentiating the etiology of the disease. Determining serum levels of folic acid and vitamin B12 is useful for identifying reversible deficits.
With regard to increased erythrolysis, this category of anemia is easily identified due to the increase in the reticulocytic index, along with a normocytic or only slightly macrocytic erythrocytic morphology. These data reflect the ability of the erythroid marrow to compensate for blood loss or hemolytic anaemia by increasing the production of erythrocytes. The level of response depends on the severity of the anaemia, as well as the nature of the initial pathological process. Since the response to blood loss is limited by the availability of iron reserves, the initial reticulocytic response usually does not exceed three times the basal level and may be short-lived.
Instead, patients with acute or chronic hemolytic anaemia will achieve this much higher level of production, which will be sustained indefinitely. While blood loss is usually clinically evident, hemolytic anemias can present in various forms. Some will appear suddenly, as an acute, self-limited episode of intravascular or extravascular hemolysis. This type of clinical picture is commonly found in patients with erythrocytic metabolic defects or autoimmune hemolytic anaemia. Patients with inherited defects of hemoglobin or erythrocytic membrane will generally describe a clinical development that begins at birth, typical of the respective pathological process.
This is especially true for patients with sickle cell or a combination of sickle cell with other hemoglobinopathy. Similar to patients with hereditary spherocytosis, a common membrane defect, will present with a complication due to the need to maintain a high level of lifelong erythrocytes production, a hemolytic or aplastic crisis, symptomatic biliary lithiasis or significant splenomegaly.
Differential diagnosis of acute or chronic hemolytic anaemia requires careful assessment of family history and belonging data to a particular race, clinical picture and a number of targeted laboratory tests. Some of the most common congenital hemolytic anemias can be identified due to erythrocytes morphology or routine laboratory tests, such as hemoglobin electrophoresis or enzyme screening test.
For example, the most common beta chain hemoglobinopathy (siclemia, hemoglobin SC disease and siclemia-talasemia) exhibit distinct types of hemoglobin at electrophoresis. Deficiency of glucoso-6-phosphate dehydrogenase (G6PD), a common erythrocytic metabolic defect, can be easily discovered by using an enzyme test G6PD. There are, however, a large number of other defects of the erythrocytic membrane, hemoglobin and intracellular metabolism that can only be identified with the help of an experienced haematological laboratory.
I will complete this post with the treatment approach. The therapeutic approach to anaemia begins during clinical evaluation. As important as carrying out careful anamnesis, physical examination and a battery of laboratory tests without delay is the rapid initiation of the indicated treatment. if the anaemia is so severe that it threatens the patient's life, therapeutic measures should be taken to ensure oxygen intake to the tissues. These include the infusion of electrolytes and colloidal solutions, to correct hypovolemia, and erythrocytic mass transfusions, to ensure tissue oxygenation.
Supplementation of oxygen supply may be required. It may also be necessary to take vitamins or medicines essential for a specific type of anaemia. If anaemia is less severe, transfusion with erythrocytic mass or mineral or vitamin therapy should be postponed until the diagnosis is safe. "Aggressive" treatment with iron and a few vitamins administered simultaneously is never appropriate. The choice of therapy should be made according to the cause or causes of the anaemia. Often, more than one etiological factor should be acted upon.
For example, a patient with end-stage anaemia of a kidney disease will require treatment with erythropoietin to compensate for the loss of cells that secrete erythropoietin. However, the effectiveness of recombinant erythropoietin depends on the status of the patient's iron reserve. If the patient lacks adequate reticuloendothelial deposits, insufficient iron reserves will prevent the erythroid marrow from proliferating after administration of erythropoietin. Therefore, it is important to evaluate the patient's iron reserves before or after the start of treatment.
Therapeutic options for treating various forms of anemia have greatly increased over the past two decades. Blood components are immediately available and are extremely safe. Effective treatments are well established for nutritional anaemias, hypoproliferative ones associated with the final stage of kidney disease and chronic inflammation and hemolytic anaemias associated with autoimmune diseases. An effective chemotherapy treatment has also become available to help prevent seizures in sickle cell disease. many congenital defects of hemoglobin structure and hemoglobin synthesis are expected to be treated by the latest molecular engineering techniques in the future.
And, I'm done with this post.... I hope to go back to the "more often" posts...
Let's move on to addressing the diagnosis of anemia! Evaluation of anaemia, whether a primary haematological disorder or secondary to another disease, is common in medical practice, the success of this assessment depends not only on the knowledge and understanding of the doctor but also on the speed and skill with which it is achieved. As a general rule, significant anaemia should be assessed without delay, using a battery of laboratory tests, to obtain clear information about the erythropoietic anomaly. This will avoid misinterpretation of a test due to changes in the patient's clinical status.
For example, the diagnosis of a nutritional anemia will be prevented if the patient changes his diet or receives vitamins or mineral supplements. A pre-test blood transfusion will alter the measurement of the production of erythrocytes required for diagnosis by reducing the response to erythropoietin. It is important not to assume a diagnostic relationship before the paraclinical examination. Even if the etiology of anaemia is suggested by the clinical picture, a full laboratory evaluation is essential. Anemias are the result of several associated factors and not of one.
The first step in diagnosing anaemia is its initial classification, taking into account the functional defect of erythropoiesis (if there is a failure in the production of erythrocytes, an abnormality in the maturation of precursors or an increase in erythrolysis). In a patient with moderate to severe anaemia, the reticulocytic index and HLG are sufficient to make a distinction. Thus, a defect in the production of erythrocytes (hypoproliferative anemia) will be characterized by a low reticulocytic index and a small or no change in the morphology of erythrocytes, this being a normochrome, normocytic anemia.
The maturation disorder also has a low reticulocytic index, but is accompanied by a morphology of either microcytic or macrocytic. Increased erythrocytosis secondary to hemolysis or hemorrhage typically leads to increased reticulocyte index to levels three times higher than normal. The morphology of erythrocytes depends on the specific type of condition. VEM is usually normal or slightly elevated, depending on the level of reticulocytosis. Examination of the smear may reveal characteristic cellular forms, which can help in the development of the specific diagnosis. Classification of anaemia according to the functional defect is helpful in choosing the laboratory tests to be carried out next.
Most anemias encountered in medical practice are hypoproliferative ones, they appear as a result of insufficient response of the medullary production of erythrocytes to the degree of anemia. They can result from bone marrow damage, iron deficiency or insufficient erythropoietin secretory response to anemia. The last cause may reflect inhibition of the release of erythropoietin by inflammatory cytokines, low metabolic needs or permanent loss of peritubular interstitial cells in the final stages of a kidney disease.
Laboratory tests to help differentiate these defects include iron deposit assessment and bone marrow examination. Patients with anaemia due to this acute or chronic inflammation have characteristic values of serum iron, CTLF and serum ferritin. The same goes for iron losses leading to iron deficiency. Primary deficiency in the proliferation of precursors, due to a medullary lesion caused by a drug, a leukaemia alteration or a tumor infiltration, can usually be diagnosed by examining the morphology of the bone marrow.
Maturation defects of erythrocytic precursors are initially recognized by the association of a low reticulocyte index with a distinct change in cellular morphology. Patients have either macrocytic anaemia (VEM greater than 100 fl) or microcytic anaemia (VEM less than 80 fl). The low erythrocytic production index reflects the insufficiency of erythropoiesis caused by altered precursor maturation. Examination of medullary morphology will indicate an increase in the E/G ratio at levels greater than 1:1, which confirms the proliferation of the erythroid marrow. The reason for the poor maturation of precursors may be obvious. A defect in nuclear maturation, which causes macrocytic anaemia, will be accompanied by a megaloblastic morphology of the bone marrow. Patients with maturation defects of the cytoplasm will experience a decrease in hemoglobin load of more mature erythrocytic precursors.
Severe iron deficiency and inherited defects in the synthesis of globin chains (thalasemias) cause moderate to severe hypochroma, microcytic anaemia. These disorders can be easily differentiated based on the morphology of the blood smear and the racial origin of the patient. If this is not possible, the evaluation of iron reserves will help in the development of the diagnosis. Anomalies inherited or acquired in mitochondrial function can lead to either microcytic or macrocytic anaemia. Based on the detection of ringed sideroblasts on the colored medullary smear, they are first classified as sideroblastic anemias.
And in this case, the evaluation of iron reserves is important for differential diagnosis and patient approach. Nuclear maturation defects are due to folic acid or vitamin B12 deficiency, exposure to a chemotherapy agent and a myelodisplastic or preleukemic condition. Regarding the differential diagnosis of cytoplasmic defects, medullary morphology and evaluation of iron reserves are useful in differentiating the etiology of the disease. Determining serum levels of folic acid and vitamin B12 is useful for identifying reversible deficits.
With regard to increased erythrolysis, this category of anemia is easily identified due to the increase in the reticulocytic index, along with a normocytic or only slightly macrocytic erythrocytic morphology. These data reflect the ability of the erythroid marrow to compensate for blood loss or hemolytic anaemia by increasing the production of erythrocytes. The level of response depends on the severity of the anaemia, as well as the nature of the initial pathological process. Since the response to blood loss is limited by the availability of iron reserves, the initial reticulocytic response usually does not exceed three times the basal level and may be short-lived.
Instead, patients with acute or chronic hemolytic anaemia will achieve this much higher level of production, which will be sustained indefinitely. While blood loss is usually clinically evident, hemolytic anemias can present in various forms. Some will appear suddenly, as an acute, self-limited episode of intravascular or extravascular hemolysis. This type of clinical picture is commonly found in patients with erythrocytic metabolic defects or autoimmune hemolytic anaemia. Patients with inherited defects of hemoglobin or erythrocytic membrane will generally describe a clinical development that begins at birth, typical of the respective pathological process.
This is especially true for patients with sickle cell or a combination of sickle cell with other hemoglobinopathy. Similar to patients with hereditary spherocytosis, a common membrane defect, will present with a complication due to the need to maintain a high level of lifelong erythrocytes production, a hemolytic or aplastic crisis, symptomatic biliary lithiasis or significant splenomegaly.
Differential diagnosis of acute or chronic hemolytic anaemia requires careful assessment of family history and belonging data to a particular race, clinical picture and a number of targeted laboratory tests. Some of the most common congenital hemolytic anemias can be identified due to erythrocytes morphology or routine laboratory tests, such as hemoglobin electrophoresis or enzyme screening test.
For example, the most common beta chain hemoglobinopathy (siclemia, hemoglobin SC disease and siclemia-talasemia) exhibit distinct types of hemoglobin at electrophoresis. Deficiency of glucoso-6-phosphate dehydrogenase (G6PD), a common erythrocytic metabolic defect, can be easily discovered by using an enzyme test G6PD. There are, however, a large number of other defects of the erythrocytic membrane, hemoglobin and intracellular metabolism that can only be identified with the help of an experienced haematological laboratory.
I will complete this post with the treatment approach. The therapeutic approach to anaemia begins during clinical evaluation. As important as carrying out careful anamnesis, physical examination and a battery of laboratory tests without delay is the rapid initiation of the indicated treatment. if the anaemia is so severe that it threatens the patient's life, therapeutic measures should be taken to ensure oxygen intake to the tissues. These include the infusion of electrolytes and colloidal solutions, to correct hypovolemia, and erythrocytic mass transfusions, to ensure tissue oxygenation.
Supplementation of oxygen supply may be required. It may also be necessary to take vitamins or medicines essential for a specific type of anaemia. If anaemia is less severe, transfusion with erythrocytic mass or mineral or vitamin therapy should be postponed until the diagnosis is safe. "Aggressive" treatment with iron and a few vitamins administered simultaneously is never appropriate. The choice of therapy should be made according to the cause or causes of the anaemia. Often, more than one etiological factor should be acted upon.
For example, a patient with end-stage anaemia of a kidney disease will require treatment with erythropoietin to compensate for the loss of cells that secrete erythropoietin. However, the effectiveness of recombinant erythropoietin depends on the status of the patient's iron reserve. If the patient lacks adequate reticuloendothelial deposits, insufficient iron reserves will prevent the erythroid marrow from proliferating after administration of erythropoietin. Therefore, it is important to evaluate the patient's iron reserves before or after the start of treatment.
Therapeutic options for treating various forms of anemia have greatly increased over the past two decades. Blood components are immediately available and are extremely safe. Effective treatments are well established for nutritional anaemias, hypoproliferative ones associated with the final stage of kidney disease and chronic inflammation and hemolytic anaemias associated with autoimmune diseases. An effective chemotherapy treatment has also become available to help prevent seizures in sickle cell disease. many congenital defects of hemoglobin structure and hemoglobin synthesis are expected to be treated by the latest molecular engineering techniques in the future.
And, I'm done with this post.... I hope to go back to the "more often" posts...
Days full of
understanding, love and gratitude!
Dorin, Merticaru