What is Megaloblastic Anemia?
Megaloblastic Anemia is a heterogeneous group of disorders that share common morphologic characteristics.
- Erythrocytes are larger & have higher nuclear-to-cytoplasmic ratios compared to normal cells
- Neutrophils can be hypersegmented
- Megakaryocytes are abnormal
There are many different kinds of anemia that are present. However, all these types are divided into certain groups. There is anemia caused by
Sickle Cell Anemia (Read Sickle Cell Anemia Causes, Symptoms and Treatment)
Megaloblastic anemia is one of the many types of anemia. This is under the macrocytic anemia group. Such disorder happens when the patient has extra-large red blood cells experiences the incomplete formation of the RBCs. This results in undeveloped and immature cells. These cells do not function normally and can only crowd out the healthy cells. Will learn about Megaloblastic Anemia Symptoms and Treatment in detail.
Megaloblastic anemia is anemia that results from inhibition of DNA synthesis in 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.
On the cellular level in megaloblastic cells, the maturation of the nucleus is delayed, while cytoplasmic development is normal & is characterized by sizable red blood cells. This malformation causes the bone marrow to produce fewer cells, & sometimes the cells die earlier than the normal 120-day life expectancy. In lieu of being round or disc-shaped, the red blood cells can be oval.
It also results from the failure of the DNA synthesis together with the RNA synthesis. This results in a restricted cell division.
A person becomes anemic when they have a decreased number of red blood cells (RBC) in the body than what is normal. The RBC contains hemoglobin, which also has iron.
These cells help in transporting oxygen throughout the parts of the body. When one does not have enough hemoglobin, the body also will not get enough oxygen.
Anemia is a common blood disorder that affects millions of people worldwide. Most often, this condition is caused by malnutrition.
There are some forms that are hereditary and some patients that are affected because of their age. Most are treatable with iron supplements and a good diet. However, there are a few types that will be a lifelong disease.
This disorder can be caused by a deficiency or not absorbing enough folic acid and vitamin B12. Other causes are chemotherapy, genetic condition, alcohol abuse, certain medications, leukemia, and myelofibrosis.
Megaloblastic Anemia Symptoms
Different patients feel and experience different symptoms.
The most common symptoms are fatigue, irritability, paleness of the skin, decreased appetite and weight loss, muscle weakness, diarrhea, palpitations, tingling or numbing of the feet and hands, and tender and smooth tongue.
Most often, megaloblastic anemia Symptoms is similar to that of other blood conditions and medical problems. This is why a series of tests need to be done in order to identify the problem.
The patient has to be tested to check vitamin B12 and folic acid deficiency, including tests for pernicious anemia. Routine blood tests are important in order to discover this blood disorder. The doctor may also check on the patient’s medical and family history in order to rule out the other causes.
Being able to detect megaloblastic anemia in earlier time can help in alleviating and treating the symptoms. This also helps in preventing other diseases and disorders.
The symptoms of megaloblastic anemia tend to be similar to other types of anemia. Breathlessness and feeling tired are two of the most common symptoms experienced by anemic individuals.
But in case of severe anemia, the patient may experience severe weakness and cardiopulmonary signs and symptoms.
Some individuals develop a pale or jaundiced complexion because of red blood cell destruction. Some may even experience gastrointestinal symptoms like nausea, vomiting, loss of appetite, weight loss and constipation. Some may even have a sore tongue and cankers.
Many individuals may experience a spectrum of mental state changes ranging from personality changes to psychosis.
It is described as a glove and stocking type of numbness. Unsteady gait and loss of balance may also occur.
Here is a list of the common symptoms:
• Muscle weakness
• Loss of appetite
• Weight loss
• Racing pulse
• Fast heartbeat
• Smooth or tender tongue
• Tingling in hands and feet
• Numbness especially in the extremities
Causes of Megaloblastic Anemia
Megaloblastic anemia is caused by the deficiency of either folic acid or vitamin B12.
This deficiency results in the incomplete formation of red blood cells in the body. The red blood cells which are circulating in the bloodstream are immature and incompletely developed. These unhealthy red blood cells do not function like normal blood cells and instead of performing their function of oxygen transport; they crowd out the bloodstream. Because they are immature, they also have a shorter life expectancy.
When vitamin B12 deficiency is due to malabsorption due to intrinsic factor deficiency in the bloodstream, it is called pernicious anemia.
Other causes include:
• Alcohol intake
• Certain medication
• Some genetic conditions
This type of anemia is commonly seen in those of North European ancestry.
What is the Effect of Megaloblastic Anemia?
Vitamin B12 deficiency can lead to megaloblastic madness. The patient may experience personality changes, depression, and dementia. Elderly patients may even have wobbly gait, memory loss, and numbness. Some may also experience infertility, especially those with severe conditions.
Those with a serious case of megaloblastic anemia can experience organ failure. Not having enough oxygen in the body can impair the normal body processes and activities. A rare effect of this kind of anemia is damaged optic nerves.
Megaloblastic Anemia Diagnosis
The preliminary diagnosis of Megaloblastic Anemia can be obtained by a
Simple Blood Test.
This will include a complete blood count and red blood cell folate.
Your doctor will also obtain a complete history of your illness from you and perform a physical exam to confirm the diagnosis.
This will help rule out other types of anemia or other causes that may produce similar symptoms. One test that can be of particular use is the Schilling test. In this test, you ingest a certain amount of radioactive B12. Then a urine sample is obtained and evaluated.
If there is minimal B12 in the urine or B12 is completely missing, it will prove that you may not be absorbing the vitamin. In normal healthy individuals, the intestine absorbs the vitamin B12 from your diet and then gets rid of it through your urine.
Other important tests other than CBC will include:
• peripheral smear
• lactate dehydrogenase (LDH)
• indirect bilirubin
• iron and ferritin assays
• tests for cobalamin deficiency (eg, serum cobalamin, protein-bound absorption test)
• tests for folate deficiency (e.g., serum folate and red blood cell [RBC] folate)
• diagnostic abdominal imaging (for possible blind loop syndrome
• bone marrow aspiration and biopsy
Megaloblastic Anemia Treatment
In treating the megaloblastic anemia, the healthcare practitioner has to address the underlying cause. Treatment per patient may vary depending on the cause, including age, tolerance to treatments, severity of the anemia, and overall health.
Those with insufficient vitamin B12 and folic acid may need monthly injections for the respective vitamin and mineral. Supplements and diet changes may also be required in order to increase the levels of vitamin B12 and folate in the body. Taking the supplements and changing diets usually last for two to three months.
The treatment of megaloblastic anemia depends not only on the severity of the symptoms of anemia but also on the underlying cause.
Other factors that are taken into consideration are your overall health, age, tolerance and response to treatments. The treatment of this kind of anaemia is continuous especially if you suffer from pernicious anaemia to ensure that it does not return.
In fact for a general lack of vitamin B12 or pernicious anemia you need monthly injections of vitamin B12. Oral supplements can also be helpful.
Supplementing your diet with food items like eggs, chicken, fortified cereals, and milk and shellfish is also very important.
If the folic acid deficiency is the cause of this type of anemia then supplementation with oral folic acid or injections of folic acid can be helpful.
Intake of Fruits and Vegetables
Dietary items like oranges, leafy vegetables, peanuts, lentils, and asparagus can also provide folic acid in the diet. It is important to start treatment when megaloblastic anemia symptoms begin to appear to avoid further complications.
Megaloblastic Anemia Treatment Guidelines
• Cobalamin therapy
A parenteral dose of cobalamin (vitamin B12) should be given on a daily basis for the duration of two weeks.
The recommended daily dose is 100-1000 µg although a dose of 1000 µg is too large and is required for only a few individuals only. Those individuals who show a more severe degree of neurological impairment should be treated with a more aggressive protocol. Cobalamin can also be administered through an oral dose.
The recommended range is 1000-2000 µg although the doses and schedules can be varied according to individual requirement. The absorption of cobalamin can be varied in different individuals hence the oral dosages are monitored more strictly.
To avoid these abnormalities in oral cobalamin absorption, it is preferred to give cobalamin parenterally.
It may be a practical strategy to start with parenteral therapy then shift to oral cobalamin. Advantages offered by oral cobalamin are that it is less expensive and better tolerated by those undergoing treatment.
In some conditions, however, like hemophilia, oral treatment is preferred to avoid the risks associated with intramuscular injections.
Serum potassium may fall severely during therapies for folate or cobalamin deficiencies and it should be closely monitored to avoid the risk of complications. Potassium supplements may be required to avoid this problem
• Folate therapy
Oral administration of folate is also a treatment for megaloblastic anemia.
The recommended dosage is 3-5 mg.
However, if there is difficulty in oral administration or compliance, then folate can also be administered parenterally. Folate should especially be administered prophylactically in pregnancy, lactation and shortly after birth.
It not only prevents symptoms of megaloblastic anemia from arising but also helps prevent neural tube effects. Fortification of food and folic acid supplements can have many health benefits.
However, there are some opponents to this therapy as it may mask the early signs of anemia due to cobalamin deficiency and it may appear with more serious neurological signs.
Megaloblastic Anemia Treatment Result
Although most patients start to feel better soon after the therapy is started, it is best to monitor if the therapy has been truly effective or not.
The elevated level of lactate dehydrogenase (LDH) and indirect bilirubin should drop if the therapy has been effective.
A prolonged increased level of LDH indicates that the therapy has not been effective.
Reticulocytosis( growth of new red blood cells) should be observed in 3-5 days and should reach a peak level in ten days.
The hyper-segmented neutrophils that are a characteristic feature of megaloblastic anemia will take over 10 to 14 days to return to normal.
The hemoglobin level should be tested every week and it should rise with at a rate of 1g/dL per week.
This rise can be used as a useful indicator to monitor response.
If no noticeable change is observed even after 2 months, other causes of anemia should be analyzed.