Macrocytic anemia can be considered as nonmegaloblastic or megaloblastic. Now that we know what tests to run and how to differentiate between multiple etiologies of microcytic anemia based on lab results, we will put it all together. A raised reticulocyte count may indicate rapid turnover of erythrocytes. The differential diagnosis and cause of anemia can then be further refined based on the results of testing. Effects on the fetus are uncommon but, if they occur, often include fetal growth restriction. The cause of macrocytic anemia is classified into one of the following categories, megaloblastic or nonmegaloblastic. Nov 24, 2018 now that we know what tests to run and how to differentiate between multiple etiologies of microcytic anemia based on lab results, we will put it all together. Diagnosis and treatment of macrocytic anemias in adults. A practical approach to the differential diagnosis and evaluation of. Anemia of chronic disease is suggested by low iron levels and decreased total ironbinding capacity. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Less commonly, also due to acquired abnormalities of their metabolism. Prealbumin malnutrition important cause of macrocytic anemia reticulocyte count hemolysis or recovery from blood loss anemia.
Once macrocytosis has been identified, differential diagnosis should begin with determining the serum levels of vitamin b12 and folate and examining the peripheral blood smear figure 1. White blood cell wbc and platelet counts may be decreased in primary marrow disturbances. Hemolytic anemias can be due to numerous causes, including rbc membrane disorders, rbc enzyme defects, immune conditions, hemoglobinopathies, and thrombotic microangiopathies, among other causes see. Discuss types of anemia and their clinical manifestations. Megaloblastic anaemia is not a final diagnosis and a cause for the condition must be sought.
Christopher hook, md macrocytosis, as defined by an elevated red blood cell mean corpuscular volume mcv, is a relatively common finding in adult patients undergoing automated cell. In aplastic anemia, bone marrow contains fewer blood cells than normal. Many cases of dietary folic acid or b 12 deficiency and sprue cannot be distinguished from pernicious anemia by any available criterion. Diagnostic tests for macrocytic anemia including blood tests, urine tests, swabs, diagnostic tests, lab tests, and pathology testing. Simultaneous measurement of reticulocyte and red blood cell indices in healthy subjects and patients with microcytic and macrocytic anemia. Normally it is not needed to make the diagnosis of vitamin b12 deficiency.
Evaluate vitamin b 12 deficiency in individuals with macrocytic or unexplained anemia, or unexplained neurologic disease in patients with megaloblastic anemia and normal vitamin b 12 levels with neurological symptoms present and suspicion for vitamin b 12 deficiency. Evaluation of microcytosis american family physician. The cause of macrocytic anemia may be due to a variety of illnesses and demands further clinical and laboratory assessment. The physical examination of patients with macrocytic anemia is frequently. Different types of macrocytic anemia can be classified depending. Laboratory testing for suspected folate deficiency starts with. Macrocytic anemia an overview sciencedirect topics. A differential diagnosis of macrocytosis is sought for the purpose of differentiating it from the other kind of macrocytosis and other associated diseases and disorders. Anemia is defined as a decrease in rbc mass, with reduced hemoglobin andor hematocrit. Diagnostic tests for macrocytic hyperchromic anemia. Thus, even mild, asymptomatic anemia should be investigated so that the primary problem can be diagnosed and treated. Megaloblastic anemia differential diagnoses emedicine. There are a many various causes of anemia, and looking at the mean.
Macrocytic cells are red blood cells larger than the nucleus of a small lymphocyte. Spurious automated red cell values in warm autoimmune hemolytic anemia. Because evaluation of rbc size is key to the diagnosis of an anemia, the. Mar 15, 2017 macrocytic anemia, then, is a condition in which your body has overly large red blood cells and not enough normal red blood cells. It should be part of the differential diagnosis for any normocytic or. A practical approach to the differential diagnosis and evaluation of the adult patient with macrocytic anemia. Nov 01, 2010 ferritin measurement is recommended as the first laboratory test for evaluation of microcytosis. The hemoglobin concentration and hematocrit may help guide diagnosis and determine the presence and severity of anemia. Megaloblastic anemia mba may cause a problem in differential diagnosis from other conditions which may cause macrocytosis. Macrocytic anemia, defined as a mean cell volume mcv. Jul 21, 2019 this anemia is caused due to the deficiency of vitamin b12 andor folic acid. This topic will discuss about laboratory investigations for the differential diagnosis of ida from those conditions. Differential diagnosis of normocytic anemia pb smear, reticulocyte count screen for liver, endocrine, renal disease. Macrocytosis is a descriptive term for red blood cell rbc size larger than the normal range.
No complications are directly attributable to the increased size of the red cell. Actually, you seldom need this test because the patient history is often sufficient. Feb 08, 2019 other potential causes of macrocytosis liver disease, hypothyroidism, and hemolytic anemia should be considered in the differential diagnosis. This topic discusses causes of macrocytosis and macrocytic anemia. Megaloblastic anemia and other causes of macrocytosis. The needle attaches to a test tube, where the blood collects. In pernicious anemia, other causes of vitamin b12 deficiency, or folate deficiency, these usually reveal. A practical approach to the differential diagnosis and. Learning objectives at the end of this briefing, you should know clinical presentation of anemia. After you confirm microcytosis the next step is to order a ferritin level.
The differential diagnosis of various types of macrocytic anemia often presents difficult clinical problems. Macrocytosis symptoms,causes,diagnosis and treatment. In normocytic anemias, the mcv is within the reference range, generally between 80100 fl. Evaluation of macrocytosis american family physician. The first step, recognition of megaloblastosis, requires attention to altered blood cell size and morphology. The definitive test for iron deficiency anemia ida is measurement of serum ferritin. Macrocytic anemia describes an anemic state characterized by the presence of abnormally large rbcs in the peripheral blood.
An mcv greater than 100 fl is macrocytosis by definition. This topic discusses causes of macrocytosis and macrocytic. A test to determine the size and shape of your red blood cells. Anemia in pregnancy merck manuals professional edition. An anemia with a high mch is called macrocytic anemia. Failure to diagnose and treat the cause of the macrocytosis is a medicolegal pitfall. Serum ferritin measurement is the first laboratory test recommended in the evaluation of. Macrocytic anemia can usually be divided into two categories, megaloblastic and nonmegaloblastic, based on the examination of the bone marrow. Sickle cellbetathalassemia is similar to hb sc disease but is less common and more benign. Aplastic anemia diagnosis and treatment mayo clinic. History and physical examination are followed by laboratory testing with a. The disease increases risk of pulmonary infarction by occasionally causing bony spicule embolization.
Deficiency results in megaloblastic anemia due to impaired. In addition to the conditions listed in the differential diagnosis, liver disease should also be considered. Macrocytic anemia is caused by various disorders such as folate and vitamin b 12 deficiencies, alcoholism, liver disease, hypothyroidism, and myelodysplastic syndromes box 61. Laboratory tests symptoms of anemia will usually be investigated initially with a complete blood count cbc and differential. Macrocytosis and macrocytic anaemia information patient. Mean cell volume mcv is a calculated average red blood cell rbc volume. Hb sc disease may first cause symptoms during pregnancy. Dec 06, 2018 iron deficiency anemia ida may cause a problem in differential diagnosis from other hypochromic anemias like betathalassemia trait, alphathalassemia trait, hbe disease, sideroblastic anemia or anemia due to chronic diseases. It may be caused by abnormalities of rbc production in the bone marrow, altered rbc membrane composition, or an increase in the percentage of reticulocytes, which are larger than mature rbcs. Macrocytic anemia causes, symptoms, diagnosis and test. Go to anemia, chronic anemia, megaloblastic anemia, myelophthisic anemia, hemolytic anemia,and sideroblastic anemias for complete information on these topics. Some of your red blood cells might also be examined for unusual size, shape and color.
Megaloblastic anemia is a type of anemia, a blood disorder in which the number of red blood cells is lower than normal. Alternative tests to the schilling test are antibodies to parietal cells. Decreased serum iron and ferritin and increased serum transferrin levels confirm the diagnosis of iron deficiency anemia. This topic will discuss about laboratory investigations for the differential diagnosis of mba from those conditions, along with some preliminary investigations. This index, with high sensitivity for beta thalassemia screening, can be a useful tool in the differential diagnosis of microcytic anemia, so samples can be chosen for hba2 analysis, to confirm. Lab diagnosis test 2 hematology flashcards quizlet. There is defective deoxyribonucleic acid dna synthesis. Macrocytosis is a descriptive term for red blood cell rbc size larger than the. Folate deficiency is suspected if cbc shows anemia with macrocytic indices or high rbc distribution width rdw. The effect of pteroylglutamic acid administration on the serum vitamin b12 concentration in pernicious anemia in relapse.
Diagnosis and treatment of macrocytic anemias in adults ncbi. Macrocytosis is a relatively common finding in the era of automated blood cell counters, with prevalence estimates ranging from 1. Categorized by mean corpuscular volume, anemia can be differentiated into microcytic, macrocytic and normocytic anemias. A doctor uses a needle to remove a small sample of bone marrow from a large bone in your body, such as your hipbone. Megaloblastic anemias are a group of macrocytic anemias in which the bone marrow shows megaloblastic erythropoieses. Occasionally, the morphologic changes in hematopoietic cells are extremely bizarre and can be misinterpreted as. This results in a reduced number of abnormally large rbcs and anemia.
Evaluation of anemia merck manuals professional edition. A reticulocyte count test is often done when someone is believed to have an illness called anemia, which happens when your body doesnt make enough red blood cells. If you receive a diagnosis of anemia, your doctor might order additional tests to determine the cause. This index, with high sensitivity for beta thalassemia screening, can be a useful tool in the differential diagnosis of microcytic anemia, so samples can be. According to who, the criteria for anemia is when adult males have hemoglobin levels gdl and adult females have 12 gdl. Confirming a diagnosis of aplastic anemia requires a. Which tests should be performed in the workup of macrocytic anemia.
Complete diagnostic testing should only be performed in cases of unexplained macrocytic anemia. Longterm treatment is not warranted except with chronic conditions such as malnutrition, exfoliative dermatitis or hemolysis. History and physical examination, vitamin b12 level, reticulocyte. Though anemia of chronic disease acd is the most common cause of such anemias1, the differential diagnosis is extensive, including blood loss, hemolytic anemias, anemia of renal. Excellent lab test to distinguish iron deficiency anemias from other microcytic. Anemia where there is no response to either of the treatment. Iron deficiency anemia ida may cause a problem in differential diagnosis from other hypochromic anemias like betathalassemia trait, alphathalassemia trait, hbe disease, sideroblastic anemia or anemia due to chronic diseases. We conclude that measurement of reticulocyte maturation parameters may be a very useful tool in the differential diagnosis of macrocytic anemia. This anemia is caused due to the deficiency of vitamin b12 andor folic acid. When the peripheral smear indicates megaloblastic anemia. Megaloblastic anemia is a subgroup of macrocytic anemia which is characterized by defective nuclear maturation. Diagnostic approach to anemia arup university of utah. Sep 15, 2018 hemolytic anemia is defined by the premature destruction of red blood cells, and can be chronic or lifethreatening. Feb 25, 2016 a basic approach to diagnosing anemia for medical students.
A practical approach to the differential diagnosis and evaluation of the adult patient with macrocytic anemia gerardo colonotero, md, david menke, md, and c. The presence of extremely high values of irf 16%, mfi 18 and mrv 129 fl, makes the diagnosis of nmma very unlikely. Hemolytic anemias, which result from premature destruction of red blood cells rbcs, may be hereditary or acquired. Evaluation of anemia differential diagnosis of symptoms. Utility of reticulocyte maturation parameters in the. The cause of macrocytosis may first be analysed by a full blood count test of a blood film. The diagnostic approach to megaloblastic anemia involves four usually sequential steps. Macrocytosis is a normal finding in newborns and during pregnancy but. Laboratory testing may include a cbc, peripheral blood smear, and reticulocyte count. Megaloblastic anemia and other causes of macrocytosis ncbi. Diagnostic tests for macrocytic hyperchromic anemia including blood tests, urine tests, swabs, diagnostic tests, lab tests, and pathology testing.
Normocytic anemia can be further divided into intrinsic and extrinsic rbc defect and blood loss. Other diagnoses to consider include anemia of chronic disease, lead toxicity, and sideroblastic anemia. Macrocytic anemia, then, is a condition in which your body has overly large red blood cells and not enough normal red blood cells. Dec 16, 2018 no complications are directly attributable to the increased size of the red cell. Anemia is defined as a hemoglobin hb level 16%, mfi 18 and mrv 129 fl, makes the diagnosis of nmma very unlikely. Preferred test is vitamin b 12 test that reflexes to serum methylmalonic acid. Approach to diagnosis of anemia classification of anaemia distinct features of each type of anemia.
Hemolytic anemia is defined by the premature destruction of red blood cells, and can be chronic or lifethreatening. Macrocytic anemias are a group of anemias in which the rbcs are larger than normal mcv 100 fl. Macrocytosis refers to a blood condition in which red blood cells are larger than normal. Anemia is defined as a hemoglobin hb level differential diagnosis of macrocytic anemia. A basic approach to diagnosing anemia for medical students. Megaloblastic anemia can be diagnosed based on characteristic morphologic. Immature red blood cells tend to be larger than mature red blood cells.
The sample is examined under a microscope to rule out other bloodrelated diseases. A low serum ferritin level is diagnostic of an irondepleted state. Thus, even mild, asymptomatic anemia should be investigated so that the primary problem can be. In general, macrocytic anemia can be divided into two major. If this is low, this diagnosis of iron deficiency is made. Megaloblastic anemia is caused by deficiency or impairment of utilization of vitamin b12 or folate. And since a low rbc count or altered rbcs can be fairly quickly detected with routine blood tests often even before signs and symptoms of anemia develop, the differential diagnosis is focused on finding the cause or risk factors that led to anemia. Pdf diagnosis and treatment of macrocytic anemias in adults. Investigations 2, 5, 6 the first investigation is fbc with examination of a blood film. Moreover, very often pernicious anemia in remission or in a nonanemic stage, and the oligosymptomatic sprue, can be.
125 625 1095 662 1652 1273 455 880 18 852 1268 31 78 872 930 153 378 801 1018 946 359 82 101 1628 1472 1347 630 669 838 568 879 579 215 1140 455 500 611 462 1246 1175 1305 707 769 714 809