Generality
Hypochromia is a condition in which red blood cells ( erythrocytes ) are paler than the norm. This situation is substantially superimposed on a reduced concentration of hemoglobin (Hb), a protein on which the red color of these blood cells depends.
Overall, the result is a reduced ability of the blood to carry oxygen, which results in the characteristic symptoms of anemia (fatigue, weakness, pallor, dizziness, etc.).
Hypochromia recognizes several causes, but more commonly it is attributable to iron deficiencies, thalassemia and chronic diseases (such as celiac disease, infections, collagen diseases and neoplasms).
Hypochromia can be diagnosed by having simple blood tests . Blood counts and average hemoglobin content of mean corpuscular volume (MCHC) are useful, in particular, to highlight the presence of pale red blood cells.
The treatment involves different approaches, including the intake of iron and vitamin C supplements, diet modification and more or less recurrent blood transfusions. Sometimes, no therapeutic intervention is necessary.
What's this
Hypochromia is a generic term that is used for any type of anemia in which red blood cells (erythrocytes) are paler than normal; the ending "ipo-" refers to minor / minus, while "-cromia" means color.
The lightest pigmentation correlates to an average hemoglobin concentration (Hb) lower than the normal reference values, for age and sex. The red color of the erythrocytes depends on this protein: Hb confers pigmentation in proportion to the volume of the blood cell. Hemoglobin is, in fact, a chromoprotein, that is, a protein combined with a colored pigment.
The role of hemoglobin
Hemoglobin (Hb) is a protein contained within red blood cells, specializing in the transport of oxygen to various parts of the body. In a healthy adult, his concentration should not fall below 12 g / dl . The reduction of hemoglobin, associated with that of red blood cells in the bloodstream, involves symptoms that characterize anemia .
Hypocromia: clinical definition
In the laboratory, the color can be assessed by measuring the mean corpuscular hemoglobin ( MCH : is the average quantity of hemoglobin carrying oxygen in the red blood cells) and / or the mean corpuscular hemoglobin concentration ( MCHC : is the calculation of the average percentage of hemoglobin inside the red blood cells). Among these two parameters, for the definition of hypochromia the MCHC is considered better, as it coincides with the concentration of Hb in a single red blood cell, therefore the indication of the color is related to the size of the cell.
Clinically, in adults, hypochromia is defined by the following values :
- MCH : below the normal reference range of 27-33 picograms / cells ;
- MCHC : below the normal reference range of 33-36 g / dL .
Hypochromia is often related to the presence of small red blood cells (microcytic), leading to a substantial overlap with the category of microcytic anemia .
Hypochromia: characteristics of red blood cells
Normally, a red blood cell has a lighter central area which, in the event of a decrease in hemoglobin within the same cell, is more extensive.
At the smear of peripheral blood followed by observation under the microscope, in the presence of hypochromia a diaphanousness of the central part of the erythrocytes is evident, which appear of a paler color.
Causes
In hypochromia, the decrease in redness is due to a disproportionate reduction in hemoglobin contained in red blood cells.
The most common causes are iron deficiency and thalassemia, but hypochromic erythrocytes can also be found in the presence of sideroblastic anemia, inflammatory states and chronic diseases .
The main pathogenetic mechanism of this condition is an altered hemoglobin synthesis, as happens, for example, in thalassemia syndromes due to deficient synthesis of one or more globin chains.
In some cases, then, erythrocytes can be clearer due to the presence of genetic mutations that interfere with erythropoiesis, that is in the formation of blood cells; in this case, one speaks of hereditary hypochromia .
Hypochromic anemia: what are the main causes?
Hypochromia can be caused by various conditions and diseases, among which the main ones are:
- Chronic iron deficiencies :
- Low iron intake;
- Decreased iron absorption;
- Excessive iron loss.
- Thalassemia (hereditary alteration of the blood that affects the chains that make up hemoglobin);
- Inflammations and chronic diseases :
- Chronic inflammatory diseases (eg rheumatoid arthritis, Crohn's disease etc.);
- Various types of neoplasms and lymphomas;
- Infections (hookworms, tuberculosis, malaria, etc.);
- Diabetes;
- Heart failure;
- COPD;
- Kidney failure;
- Diseases of the liver;
- Hypothyroidism;
- Lead poisoning (substance that causes inhibition of heme synthesis);
- Vitamin B6 (pyridoxine) deficiency ;
Less often, hypochromia can occur due to:
- Side effect of some drugs;
- Severe intestinal or stomach bleeding caused by ulcers or other conditions;
- Bleeding of hemorrhoids;
- Copper poisoning.
More rare forms of hypochromia are congenital sideroblastic anemias (due to heme deficiency synthesis) and erythropoietic porphyria .
Symptoms and Complications
Hypochromia shows very variable clinical pictures : in some cases, the disease is debilitating and puts people's lives at risk; at other times, the disorder is mild and almost asymptomatic or a sign of oneself only during physical efforts.
Depending on the cause, hypochromic anemia takes on particular characteristics both in symptoms and in the values found with laboratory tests.
What are the symptoms of hypochromia?
In general, the manifestations vary depending on the severity of hypochromic anemia and the speed with which it develops. Sometimes, this pathological condition is identified before the onset of symptoms, through simple routine blood tests.
In most cases, hypochromia involves the following manifestations:
- Pallor (accentuated at the level of the face);
- Intolerance to exercise, early fatigue, muscle weakness and fatigue;
- Brittle nails and hair;
- Anorexia (lack of appetite);
- Headache;
- Shortness of breath;
- Dizziness;
- Accelerated beats;
- Burning tongue;
- Dryness of the oral cavity;
- Abdominal pains;
- Painful cramps in the lower limbs during efforts.
Did you know that…
In the past, hypochromic anemia was called "chlorosis" or "green disease" due to the nuance that the skin sometimes took in patients.
In addition to these symptoms, the most severe hypochromic anemia can be:
- fainting;
- Palpitations;
- Confusion;
- Pulse weak and rapid;
- Wheezing and accelerated breathing;
- Chest pain;
- Increased thirst;
- Jaundice;
- Blood loss and bleeding tendency;
- Recurrent fever attacks;
- Diarrhea;
- Irritability;
- Amenorrhea;
- Progressive distension of the abdomen (secondary to splenomegaly and hepatomegaly).
Diagnosis
The suspicion of hypochromia may arise due to the appearance of a suggestive symptomatology .
After collecting the medical history information, the doctor prescribes a series of laboratory investigations, with the aim of evaluating:
- Quantity and type of hemoglobin;
- Number and volume of red blood cells;
- State of body iron.
For a better characterization of hypochromia, therefore, it is useful to perform the following blood tests :
- Complete blood count:
- Red blood cell count (RBC) : erythrocyte count is generally but not necessarily decreased in hypochromic anemia;
- Erythrocyte indices : they provide useful information regarding the size of red blood cells (normocytic, microcytic or macrocytic anemias) and the quantity of Hb contained within them (normochromic or hypochromic anemias). The main ones are: Medium Corpuscular Volume ( MCV, indicates the average size of red blood cells), Medium Corpuscular Hemoglobin ( MCH ) and Medium Corpuscular Hemoglobin Concentration ( MCHC, coincides with the concentration of hemoglobin in a single red blood cell);
- Reticulocyte count : quantifies the number of young (immature) red blood cells present in peripheral blood;
- Platelets, leukocytes and leukocyte formula ;
- Hematocrit (Hct) : percentage of the total volume of blood made up of red blood cells;
- Amount of hemoglobin (Hb) in the blood;
- Red cell size variability (amplitude of red blood cell distribution, RDW ).
- Microscopic examination of the erythrocytic morphology and, more generally, of the peripheral blood smear ;
- Serum iron, TIBC and serum ferritin;
- Bilirubin and LDH;
- Indices of inflammation, including C-reactive protein.
Any anomalies in these parameters can alert laboratory personnel to the presence of anomalies in the red blood cells ; the blood sample could be subjected to further analysis to identify the cause of hypochromic anemia. Rarely, examination of a sample from the bone marrow may be necessary.
Reduced hemoglobin values and a low hematocrit (percentage of red blood cells in the total blood volume) confirm the suspicion of anemia. By definition, hypochromic anemias are characterized by a mean globular hemoglobin content ( MCH ) of less than 27 pg and a MCHC below the normal reference range of 33-36 g / dL .
The hypochromic red blood cells are often microcytic, that is, smaller than usual; in this case, we speak of hypochromic microcytic anemia .
If the blood test shows low serum levels, hypochromia is probably due to iron deficiency or secondary to chronic disease .
Treatment
The treatment of hypochromia varies depending on the cause, that is the type of anemia you suffer from.
When possible, the therapy of underlying pathologies responsible for hypochromia usually determines the resolution of the clinical condition. It should be noted, however, that some forms, such as those caused by thalassemia and some types of sideroblastic anemia, are congenital, and therefore cannot be cured.
Iron deficiency hypochromia
The iron- deficient form is the condition that is most easily manageable, as it can be tackled by varying the diet and taking iron supplements orally (or intravenously, when the patient is symptomatic and the clinical picture is severe) and vitamin C (helps to increase the body's ability to absorb iron).
Hypochromia: when it depends on other diseases
When hypochromia is related to other diseases, such as kidney failure, hypothyroidism or liver disease, instead, it is necessary to intervene in a targeted manner on the primary cause to observe improvements in symptoms.
Hereditary hypochromia
Some types of diseases, such as thalassemia and some types of sideroblastic anemia, are congenital and hereditary, so there are no treatments available, but supportive measures and symptomatic therapies.
Other therapeutic interventions
When hemoglobin falls to dangerously low levels, blood transfusions can be useful to temporarily increase the ability to transport oxygen and make up for the lack of red blood cells. Transfusion therapy may also be associated with chelating drugs, to avoid iron accumulation.
The treatment of hypochromic anemia may also include:
- Splenectomy, if the disease causes severe anemia or splenomegaly;
- Bone marrow or stem cell transplant from compatible donors.
Besides the specific therapies, great importance is given to the regular physical activity and the variation of eating habits .
In particular, it can be useful:
- Consume foods rich in calcium and vitamin D, due to the risk of osteoporosis (a disease often related to anemia);
- Take folic acid supplements (to increase red blood cell production).
Prognosis
The right attention to physical activity and nutrition, together with the most suitable therapy, can significantly improve the quality of life of people who suffer from hypochromic anemia.
