Macrocytosis

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Macrocytosis
Red Blood Cells according to sizes.png
Other namesMacrocytes
Specialty Hematology
Symptoms Shortness of breath, weakness, heart murmur, tachycardia
CausesVitamin B12 deficiency, Folic acid deficiency, Malabsorption, Alcoholism
Risk factors Bone marrow failure, hematologic malignancy
Diagnostic method Symptoms, Complete blood count, Peripheral blood smear, Vitamin B12 level, Red cell folate level

Macrocytosis is a condition where red blood cells are larger than normal. [1] These enlarged cells, also known as macrocytes, are defined by a mean corpuscular volume (MCV) that exceeds the upper reference range established by the laboratory and hematology analyzer (usually >110 fL). [2] Upon examination of a peripheral blood smear under microscope, these macrocytes appear larger than standard erythrocytes. It’s noteworthy that macrocytosis is a common morphological feature in neonatal peripheral blood. [3] The presence of macrocytosis can indicate a range of conditions, from benign, treatable illnesses to more serious underlying disorders.

Contents

Types

Macrocytes may be oval or round. Oval macrocytes (also called megalocytes) [4] are seen in conditions associated with dyserythropoiesis including megalobalstic anemia, myelodysplstic syndromes, Fanconi anemia and CDA type I & III. Round macrocytes are associated with other causes of macrocytosis.

Causes

In humans, the most prevalent causes of macrocytosis are often linked to alcoholism and deficiencies in vitamin B12 or folic acid (Vitamin B9), or a combination of these factors. [5] These conditions can affect the production and development of red blood cells, leading to their enlargement. Another cause of macrocytosis is benign familial macrocytosis, which is a hereditary condition that doesn’t present any symptoms. [6] Despite the larger size of the red blood cells, individuals with this condition typically have normal red blood cell function. It’s always important to consult with a healthcare professional for accurate diagnosis and treatment. Causes of Macrocytosis may include:

Complications

No complications arise from macrocytosis itself and a prognosis will be determined from its cause.

See also

Related Research Articles

<span class="mw-page-title-main">Anemia</span> Reduced ability of blood to carry oxygen

Anemia or anaemia is a blood disorder in which the blood has a reduced ability to carry oxygen. This can be due to a lower than normal number of red blood cells, a reduction in the amount of hemoglobin available for oxygen transport, or abnormalities in hemoglobin that impair its function. The name is derived from Ancient Greek ἀν- (an-) 'not', and αἷμα (haima) 'blood'. When anemia comes on slowly, the symptoms are often vague, such as tiredness, weakness, shortness of breath, headaches, and a reduced ability to exercise. When anemia is acute, symptoms may include confusion, feeling like one is going to pass out, loss of consciousness, and increased thirst. Anemia must be significant before a person becomes noticeably pale. Additional symptoms may occur depending on the underlying cause. Anemia can be temporary or long term and can range from mild to severe.

<span class="mw-page-title-main">Myelodysplastic syndrome</span> Diverse collection of blood-related cancers

A myelodysplastic syndrome (MDS) is one of a group of cancers in which immature blood cells in the bone marrow do not mature, and as a result, do not develop into healthy blood cells. Early on, no symptoms typically are seen. Later, symptoms may include fatigue, shortness of breath, bleeding disorders, anemia, or frequent infections. Some types may develop into acute myeloid leukemia.

Aplastic anemia (AA) is a severe hematologic condition in which the body fails to make blood cells in sufficient numbers. Aplastic anemia is associated with cancer and various cancer syndromes. Blood cells are produced in the bone marrow by stem cells that reside there. Aplastic anemia causes a deficiency of all blood cell types: red blood cells, white blood cells, and platelets.

<span class="mw-page-title-main">Thrombocytopenia</span> Abnormally low levels of platelets in the blood

In hematology, thrombocytopenia is a condition characterized by abnormally low levels of platelets in the blood. Low levels of platelets in turn may lead to prolonged or excessive bleeding. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients and a third of surgical patients.

<span class="mw-page-title-main">Pernicious anemia</span> Anemia caused by vitamin B12 deficiency

Pernicious anemia is a disease where not enough red blood cells are produced due to a deficiency of vitamin B12. Those affected often have a gradual onset. The most common initial symptoms are feeling tired and weak. Other symptoms may include shortness of breath, feeling faint, a smooth red tongue, pale skin, chest pain, nausea and vomiting, loss of appetite, heartburn, numbness in the hands and feet, difficulty walking, memory loss, muscle weakness, poor reflexes, blurred vision, clumsiness, depression, and confusion. Without treatment, some of these problems may become permanent.

<span class="mw-page-title-main">Achlorhydria</span> Medical condition

Achlorhydria and hypochlorhydria refer to states where the production of hydrochloric acid in gastric secretions of the stomach and other digestive organs is absent or low, respectively. It is associated with various other medical problems.

<span class="mw-page-title-main">Megaloblastic anemia</span> Medical condition

Megaloblastic anemia is a type of macrocytic anemia. An anemia is a red blood cell defect that can lead to an undersupply of oxygen. Megaloblastic anemia results from inhibition of DNA synthesis during red blood cell production. When DNA synthesis is impaired, the cell cycle cannot progress from the G2 growth stage to the mitosis (M) stage. This leads to continuing cell growth without division, which presents as macrocytosis. Megaloblastic anemia has a rather slow onset, especially when compared to that of other anemias. The defect in red cell DNA synthesis is most often due to hypovitaminosis, specifically vitamin B12 deficiency or folate deficiency. Loss of micronutrients may also be a cause.

Pancytopenia is a medical condition in which there is significant reduction in the number of almost all blood cells.

<span class="mw-page-title-main">Glossitis</span> Medical condition

Glossitis can mean soreness of the tongue, or more usually inflammation with depapillation of the dorsal surface of the tongue, leaving a smooth and erythematous (reddened) surface,. In a wider sense, glossitis can mean inflammation of the tongue generally. Glossitis is often caused by nutritional deficiencies and may be painless or cause discomfort. Glossitis usually responds well to treatment if the cause is identified and corrected. Tongue soreness caused by glossitis is differentiated from burning mouth syndrome, where there is no identifiable change in the appearance of the tongue, and there are no identifiable causes.

<span class="mw-page-title-main">Sideroblastic anemia</span> Medical condition

Sideroblastic anemia, or sideroachrestic anemia, is a form of anemia in which the bone marrow produces ringed sideroblasts rather than healthy red blood cells (erythrocytes). In sideroblastic anemia, the body has iron available but cannot incorporate it into hemoglobin, which red blood cells need in order to transport oxygen efficiently. The disorder may be caused either by a genetic disorder or indirectly as part of myelodysplastic syndrome, which can develop into hematological malignancies.

Reticulocytopenia is the medical term for an abnormal decrease in circulating red blood cell precursors (reticulocytes) that can lead to anemia due to resulting low red blood cell (erythrocyte) production. Reticulocytopenia may be an isolated finding or it may not be associated with abnormalities in other hematopoietic cell lineages such as those that produce white blood cells (leukocytes) or platelets (thrombocytes), a decrease in all three of these lineages is referred to as pancytopenia.

<span class="mw-page-title-main">Folate deficiency</span> Abnormally low level of folate (vitamin B9) in the body

Folate deficiency, also known as vitamin B9 deficiency, is a low level of folate and derivatives in the body. This may result in a type of anemia in which red blood cells become abnormally large and is a late finding in folate deficiency and folate deficiency anemia is the term given for this medical condition. Signs of folate deficiency are often subtle. Symptoms may include feeling tired, heart palpitations, shortness of breath, feeling faint, open sores on the tongue, loss of appetite, changes in the color of the skin or hair, irritability, and behavioral changes. Temporary reversible infertility may occur. Folate deficiency anemia during pregnancy may give rise to the birth of low weight birth premature infants and infants with neural tube defects.

<span class="mw-page-title-main">Anisocytosis</span> Medical condition

Anisocytosis is a medical term meaning that a patient's red blood cells are of unequal size. This is commonly found in anemia and other blood conditions. False diagnostic flagging may be triggered on a complete blood count by an elevated WBC count, agglutinated RBCs, RBC fragments, giant platelets or platelet clumps. In addition, it is a characteristic feature of bovine blood.

<span class="mw-page-title-main">Hydroxocobalamin</span> Form of vitamin B12

Hydroxocobalamin, also known as vitamin B12a and hydroxycobalamin, is a vitamin found in food and used as a dietary supplement. As a supplement it is used to treat vitamin B12 deficiency including pernicious anemia. Other uses include treatment for cyanide poisoning, Leber's optic atrophy, and toxic amblyopia. It is given by injection into a muscle or vein.

<span class="mw-page-title-main">Copper deficiency</span> Insufficient level of copper in the body, leading to anaemia and nervous symptoms

Copper deficiency, or hypocupremia, is defined either as insufficient copper to meet the needs of the body, or as a serum copper level below the normal range. Symptoms may include fatigue, decreased red blood cells, early greying of the hair, and neurological problems presenting as numbness, tingling, muscle weakness, and ataxia. The neurodegenerative syndrome of copper deficiency has been recognized for some time in ruminant animals, in which it is commonly known as "swayback". Copper deficiency can manifest in parallel with vitamin B12 and other nutritional deficiencies.

Vitamin B<sub>12</sub> deficiency Disorder resulting from low blood levels of vitamin B12

Vitamin B12 deficiency, also known as cobalamin deficiency, is the medical condition in which the blood and tissue have a lower than normal level of vitamin B12. Symptoms can vary from none to severe. Mild deficiency may have few or absent symptoms. In moderate deficiency, feeling tired, headaches, soreness of the tongue, mouth ulcers, breathlessness, feeling faint, rapid heartbeat, low blood pressure, pallor, hair loss, decreased ability to think and severe joint pain and the beginning of neurological symptoms, including abnormal sensations such as pins and needles, numbness and tinnitus may occur. Severe deficiency may include symptoms of reduced heart function as well as more severe neurological symptoms, including changes in reflexes, poor muscle function, memory problems, blurred vision, irritability, ataxia, decreased smell and taste, decreased level of consciousness, depression, anxiety, guilt and psychosis. If left untreated, some of these changes can become permanent. Temporary infertility reversible with treatment, may occur. A late finding type of anemia known as megaloblastic anemia is often but not always present. In exclusively breastfed infants of vegan mothers, undetected and untreated deficiency can lead to poor growth, poor development, and difficulties with movement.

The term macrocytic is from Greek words meaning "large cell". A macrocytic class of anemia is an anemia in which the red blood cells (erythrocytes) are larger than their normal volume. The normal erythrocyte volume in humans is about 80 to 100 femtoliters. In metric terms the size is given in equivalent cubic micrometers. The condition of having erythrocytes which are too large, is called macrocytosis. In contrast, in microcytic anemia, the erythrocytes are smaller than normal.

Hematologic diseases are disorders which primarily affect the blood and blood-forming organs. Hematologic diseases include rare genetic disorders, anemia, HIV, sickle cell disease and complications from chemotherapy or transfusions.

<span class="mw-page-title-main">Elliptocyte</span> Abnormal red blood cell

Elliptocytes, also known as ovalocytes or cigar cells, are abnormally shaped red blood cells that appear oval or elongated, from slightly egg-shaped to rod or pencil forms. They have normal central pallor with the hemoglobin appearing concentrated at the ends of the elongated cells when viewed through a light microscope. The ends of the cells are blunt and not sharp like sickle cells.

<span class="mw-page-title-main">Nucleated red blood cell</span> Red blood cell with a cell nucleus

A nucleated red blood cell (NRBC), also known by several other names, is a red blood cell that contains a cell nucleus. Almost all vertebrate organisms have hemoglobin-containing cells in their blood, and with the exception of mammals, all of these red blood cells are nucleated. In mammals, NRBCs occur in normal development as precursors to mature red blood cells in erythropoiesis, the process by which the body produces red blood cells.

References

  1. Kaferle, Joyce; Strzoda, Cheryl E. (2009-02-01). "Evaluation of macrocytosis". American Family Physician. 79 (3): 203–208. ISSN   0002-838X. PMID   19202968.
  2. Woodruff, James N.; Blanchard, Anita K. (2016-06-11). Primary Care of Adult Women, An Issue of Obstetrics and Gynecology Clinics of North America. Elsevier Health Sciences. ISBN   978-0-323-44623-5.
  3. Bain, Barbara J. (2015-01-20). Blood Cells: A Practical Guide. John Wiley & Sons. ISBN   978-1-118-81733-9.
  4. Anderson, Shauna Christine; Poulsen, Keila (2003). Atlas of Hematology. Lippincott Williams & Wilkins. ISBN   978-0-7817-2662-7.
  5. Pacholok, Sally; Stuart, Jeffrey J. (2011-01-01). Could It Be B12?: An Epidemic of Misdiagnoses. Linden Publishing. ISBN   978-1-61035-065-5.
  6. "Macrocytosis: Practice Essentials, Pathophysiology, Etiology". 2022-10-07.{{cite journal}}: Cite journal requires |journal= (help)