The Microcytosis Is a condition where the red blood cells in the blood are smaller than normal, measuring them by their mean corpuscular volume. This is expressed in a size of less than 80 micras3 (80fL) in adult patients.
Red blood cells are blood cells responsible for transporting oxygen to tissues and organs throughout the body, in addition to the elimination of carbon dioxide. This is achieved thanks to hemoglobin (Hb), a complex protein contained inside them with molecules that have iron. This gives the blood its red color and characteristic odor.
Hemoglobin is essential for the transport of oxygen and carbon dioxide, so a patient with red blood cell abnormalities can suffer a series of symptoms of tiredness, shortness of breath and exhaustion.
Macrocytosis is usually a chance finding in a normal blood count and patients with this condition usually remain asymptomatic. It is usually a specific indicator of iron deficiency anemia, thalassemia, and sideroacrheic anemia.
Causes
Alterations in the size of red blood cells, also called erythrocytes or red blood cells - are known as anisocytosis, a pathological condition of red blood cells, where they vary in size rather than having the same diameter. This generates the presence of red blood cells of different sizes in the same blood sample and usually occurs in patients who have received transfusions.
During life, red blood cell and hemoglobin levels vary and in infancy the mean corpuscular volume and corpuscular hemoglobin are lower. Then, hemoglobin levels can also be affected by smoking, altitude, among other factors.
Erythrocytes are recognized both by their size and by the presence of hemoglobin in their interior. This protein defines the color of the cells, although there is also the possibility that there are red cells affected with microcytosis but with a normal coloration. This is because a relatively adequate amount of hemoglobin is still maintained inside the cell.
In the case of microcytosis, red blood cells are smaller than the corpuscular volume they should have. The erythrocytes may be small due to mutations in their formation, which is known as hereditary microcytosis; Or may also be associated with iron deficiencies; Since red blood cells do not contain enough hemoglobin inside.
Depending on the patient's age and gender, there are several causes of microcytosis. For example, in children and adolescents the most common are iron deficiency anemia (microcytic anemia), thalassemia, lead poisoning or lead poisoning, sideroblastic anemia, or chronic inflammation.
In the case of women, it is usually due to anemia due to iron deficiency, thalassemia, pregnancy, sideroblastic anemia and anemia due to chronic diseases. If the woman is not menstruating, the factors are the same that cause microcytosis in a man, again including iron deficiency anemia, chronic disease, thalassemia and anemia without an identified cause.
That is why the most common cause is anemia due to lack of iron. In this case, microcytosis is not related to a reduction of DNA synthesis or genetic alteration. This condition is known as microcytic anemia.
When microcytic anemia is suspected, measurement of iron in the blood through a ferritin test in the blood is essential. Ferritin is the protein within the cells that stores iron. Values are variable in men and women, and if they are lower than 12 nanograms per milliliter (ng / mL), the person is likely to have iron deficiency.
This low concentration of iron in the blood may be due to a diet low in iron, bleeding from wounds - both external and internal (eg bleeding into the digestive tract: esophagus, intestines, stomach), very heavy menstrual periods or failure In the absorption of iron. One should even consider the possibility of a gastrointestinal tumor that is causing occult bleeding.
However, the most common and common cause is anemia. Although it is most likely to be an iron deficiency anemia.
Diagnosis
Microcytosis is usually diagnosed through a blood test and the results obtained may collect more information on the etiology of the disorder according to the patient's report. Nutrition information is critical, for example, if you have cravings for ice or pica - which corresponds to an abnormal anxiety about eating soil or other minerals, reflecting a lack of iron.
It should be investigated if the patient for his work or occupation has contact with heavy metals such as lead, which could be causing intoxication and a picture of lead poisoning. It is also important to ask if in your family there are stories of anemia, thalassemia; Or if you have suffered from chronic infections, illness or permanent inflammatory processes.
Gastrointestinal symptoms are very relevant, distension and abdominal pain, all kinds of gastric annoyances and bleeding in vomiting or stools can give information of some internal problem that leads to bleeding and therefore to microcytosis.
In the case of women, the history of their menstrual periods is indicative of greater or lesser blood loss which can also lead to anemia.
symptom
Affected patients often suffer from these symptoms, to a greater or lesser extent depending on the severity of the anemia:
- Weakness and fatigue.
- Severe headaches.
- Difficulty concentrating and focusing on tasks.
- Chest pain.
- Lack of appetite and loss of weight.
- Changes in the texture and color of the nails. Brittle, pale, soft nails.
- Slightly yellowing of the eyes.
- Menstrual flow abundant in the case of women.
- Pica: Urgency for eating dirt or minerals to compensate for the lack of iron.
- Cold skin to the touch.
Related diseases
There are also other conditions that can provoke microcytosis. One of these is thalassemia. Beta-thalassemia is an autosomal recessive genetic disorder in which the person does not produce enough hemoglobin because it does not generate the protein chains necessary for the construction of hemoglobin.
The body in these patients generates an abnormal form of hemoglobin, resulting in destruction of red cells leading to anemia. It is a genetic condition that is passed down from generation to generation and usually affects people from Southeast Asia, the Middle East, descendants of Africans and Chinese.
Some symptoms of this disease are deformities in the bones of the face, failure of growth, dyspnea (shortness of breath), habitual fatigue and yellow skin (jaundice). People who have the minor form of thalassemia are those with microcytosis but without this symptomatology associated with their disease.
On the other hand, microcytic anemia can also be generated by thalassemia or iron deficiency in the blood. There are five main causes that in English form the acronym TAILS. These include thalassemia, chronic disease anemia, iron deficiency, congenital sideroblastic anemia, and lead poisoning (poisoning caused by exposure to lead). Each of these causes can be ruled out with more blood tests, where microcytosis is only one of the abnormalities that the cells present.
In the case of microcytic anemia, small red blood cells with insufficient hemoglobin do not have the capacity to bring enough oxygen to the whole body. This produces in the patients symptoms like lack of appetite, general pallor, brittle nails, dry mouth, among others.
Depending on the severity of the anemia, the patient may be asymptomatic or present various variations of fatigue, dizziness and dyspnea.
Nutritional deficiency is undoubtedly the major cause of microcytic anemia, especially in children. In the case of women, the preponderant factor results to be very abundant blood losses during menstruation. In adult men and women who do not menstruate, it is worthwhile to extend the studies in case of concealed bleeding, as in tumors or other pathologies of the gastrointestinal tract (gastritis, esophagitis, ulcers, celiac disease, among others).
Another cause of microcytosis is chronic disease anemia. This occurs when there are chronic inflammatory processes or infections. In these cases, increased cytokine levels produce a decrease in the production of erythropoietin, which interferes with iron metabolism. Some of these anemias have traits of microcytosis. Their prognosis is favorable and they are not progressive.
Treatment of microcytosis
In general, the treatment of microcytosis is to increase iron intake in the diet, thereby achieving adequate hemoglobin levels and increasing the size of red blood cells.
Iron enters the body through the food we eat, in dairy products, soy protein and meats. Other sources of iron that are not of animal origin are lentils, whole grain products, dried fruits and beans.
To increase the absorption of iron in the diet it is recommended to mix it with products that contain vitamin C such as berries, citrus fruits, tomatoes and melons. Foods rich in calcium - such as dairy products - interfere with the absorption of iron, so it is recommended to consume them separately if the goal is to increase iron levels in the body.
If a greater increase of iron in the organism is necessary, the supplements can be considered. The recommended dose is 60 milligrams (mg) of iron once or twice daily. Ideally, iron capsules should be taken alone, so that no other element influences their absorption. In addition, taking 500 mg daily of ascorbic acid - vitamin C - together with the iron supplement promotes greater beneficial effects.
Treatment with iron supplements is usually effective against anemia. However, in patients who do not respond to these measures or have recurrent anemias, more studies are needed to identify the cause that continues to cause it.
In rare cases, blood transfusion is used to treat iron deficiency anemia. This treatment is usually used in hospitalized patients with cardiovascular disease who have a hemoglobin threshold of less than 7-8 ng / mL.
Basically, microcytosis can be prevented and treated with an increase in iron intake in food, either through food containing it or external supplements. If anemia does not improve, we recommend seeking medical help.
References
- Mach-Pascual S, Darbellay R, Pilotto PA, Beris P (July 1996). "Investigation of microcytosis: a comprehensive approach". Eur. J. Haematol . 57 (1): 54-61.
- "Microcythemia"at Dorland's Medical Dictionary.