Diagnosing Anemia: Key Blood Tests to Identify the Underlying Cause

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• Two Key Blood Tests for Anemia Diagnosis
• High Reticulocyte Count: Bleeding and Hemolysis
• MCV Analysis: Red Blood Cell Size and Its Meaning
• Identifying Hidden Sources of Bleeding
• Modern Treatments for Different Anemia Types
• Full Transcript

Two Key Blood Tests for Anemia Diagnosis

Dr. Aric Parnes, MD, a hematology expert, identifies two critical blood tests to find the cause of anemia. The first is the reticulocyte count. This test measures young red blood cells. An elevated count indicates the bone marrow is responding to blood loss or destruction.

The second essential test is the mean corpuscular volume (MCV). MCV measures the average size of red blood cells. This value helps categorize the anemia. It points toward specific nutritional deficiencies or underlying bone marrow disorders.

High Reticulocyte Count: Bleeding and Hemolysis

A high reticulocyte count signals that the body is trying to replace lost red blood cells. Dr. Aric Parnes, MD, explains this often results from bleeding. Bleeding can be obvious, like from a wound, or hidden internally.

Alternatively, a high count can indicate hemolysis. Hemolysis is the destruction of red blood cells within the body. Dr. Aric Parnes, MD, notes that autoimmune hemolytic anemia is a common cause. This occurs when the immune system mistakenly attacks its own red blood cells.

Confirming hemolysis requires additional lab tests. Dr. Parnes lists three key indicators: elevated lactate dehydrogenase (LDH), elevated bilirubin, and decreased haptoglobin. These markers confirm red blood cell breakdown is occurring.

MCV Analysis: Red Blood Cell Size and Its Meaning

The mean corpuscular volume (MCV) is a powerful diagnostic tool. Dr. Aric Parnes, MD, details how MCV values guide the diagnosis. A low MCV indicates microcytic anemia, where red blood cells are too small.

Common causes of a low MCV include iron deficiency and thalassemia. A high MCV indicates macrocytic anemia, with larger-than-normal cells. This is often caused by vitamin B12 or folate deficiency. Dr. Parnes also notes that bone marrow diseases like myelodysplastic syndrome or aplastic anemia can cause a high MCV.

A normal MCV presents a different diagnostic picture. Dr. Anton Titov, MD, and Dr. Parnes discuss how this often points to anemia of inflammation, formerly called anemia of chronic disease. Chronic kidney disease is a major cause of this type of anemia.

Identifying Hidden Sources of Bleeding

Occult bleeding is a frequent and serious cause of anemia. Dr. Aric Parnes, MD, emphasizes that microscopic blood loss can be the first sign of a major health issue. In the gastrointestinal tract, this bleeding can stem from colon polyps or colon cancer.

Diagnosing this requires specific procedures. A colonoscopy is essential to visualize the colon and find polyps or tumors. If a colonoscopy is negative, an upper endoscopy is performed. This procedure examines the stomach and duodenum for ulcers, gastritis, or rare tumors like a gastrointestinal stromal tumor (GIST).

Dr. Parnes stresses the importance of these investigations. Finding and treating the source of bleeding is crucial for resolving the anemia and addressing the underlying condition.

Modern Treatments for Different Anemia Types

Treatment for anemia depends entirely on its cause. Dr. Aric Parnes, MD, outlines modern therapeutic options. For iron deficiency, oral iron supplements are a first-line treatment. However, many patients experience side effects like GI upset.

Intravenous iron offers a potent alternative. Dr. Aric Parnes, MD, explains that IV iron can restore iron levels in minutes, compared to the months required with oral tablets. For anemia of chronic kidney disease, the treatment is erythropoietin replacement therapy.

Erythropoietin (EPO) is a hormone produced by healthy kidneys. Injections of synthetic EPO (like Epoetin or Darbepoetin) stimulate the bone marrow to produce red blood cells. This treatment, administered weekly or monthly, effectively manages anemia and reduces the need for blood transfusions. Dr. Anton Titov, MD, notes that EPO is also used for anemia in myelodysplastic syndrome.

Full Transcript

Dr. Anton Titov, MD: How to find the cause of anemia? Two key blood tests show the cause of anemia. Why do you have anemia? A complete blood count can help with diagnosis. How can anemia be a first sign of colon cancer? How to find the real cause of anemia? How to treat anemia of chronic disease?

A top hematology expert discusses two important blood tests to find the exact cause of anemia. How to find the cause of anemia. Two key blood tests.

Dr. Anton Titov, MD: How is anemia diagnosed? A video interview with a top expert in hematology on the diagnosis of anemia. A medical second opinion in anemia helps to make sure the anemia cause is found.

Dr. Aric Parnes, MD: A medical second opinion ensures that the diagnosis is correct and complete. Two blood tests are important to find what causes anemia in men and women. Reticulocyte count is a blood test to identify young baby erythrocytes. Reticulocyte count establishes if bleeding or destruction of red blood cells happens in the body.

The most common causes of anemia are iron deficiency and chronic bleeding. In women, anemia can be caused by heavy menstrual periods.

Dr. Anton Titov, MD: Anemia could be a sign of colon cancer and colon polyp. A colon cancerous polyp could bleed into the intestines and it is not easy to find out. That is why colonoscopy and occult fecal blood tests are performed.

How to find the cause of anemia in chronic disease? A medical second opinion also helps to choose the best treatment for anemia. What causes anemia in children? Nutritional microelement iron deficiency could be a cause of anemia in children.

Dr. Aric Parnes, MD: How to self-diagnose anemia? You can perform a complete blood count test in an independent laboratory and look at reticulocyte count and mean corpuscular volume (MCV) numbers. But go to the hematologist to find the exact cause and treatment.

Anemia tests and diagnosis require an experienced hematologist. An expert can also give a medical second opinion on the diagnosis of anemia. How to find the cause of anemia when limited resources are available? The anemia algorithm starts with MCV and reticulocyte counts.

Treatment for anemia of chronic disease by erythropoietin injection. A video interview with a top expert in blood diseases, hematology and oncology. A medical second opinion confirms that an aplastic anemia diagnosis is correct and complete.

Dr. Anton Titov, MD: A medical second opinion also confirms that aplastic anemia treatment is required. A medical second opinion helps to choose the best treatment for aplastic anemia. Get a medical second opinion on aplastic anemia and be confident that your treatment is the best.

Anemia causes and differential diagnosis. How to find the cause of anemia.

Dr. Anton Titov, MD: Anemia is a big topic. It is perhaps the defining problem of hematology. Anemia is a sign or symptom of many diseases. Sometimes a person has a low red blood cell count.

What steps does a hematologist follow to identify the cause of anemia? Perhaps you can give examples of common causes of anemia.

Dr. Aric Parnes, MD: Sure. There are two laboratory test features that we pay most attention to diagnose anemia correctly. Number one: what is the reticulocyte count? The reticulocytes are young red blood cells.

Sometimes a person is bleeding. Their bone marrow will respond and make more blood. Sometimes erythrocytes are destroyed in the body. This is called hemolysis. Bone marrow will make more red blood cells.

In both situations, the reticulocyte count will increase. Sometimes the reticulocyte count does not increase. Then there is a problem with red blood cell production by bone marrow.

Test number two that we pay close attention to in a patient with anemia is this. It is MCV or mean corpuscular volume. It is also called mean cell volume. This is the size of the red blood cell.

People with iron deficiency have very small red blood cells. Their MCV decreases. People with thalassemia or other problems with hemoglobin have very small red blood cells. Problems with hemoglobin are called hemoglobinopathy. These patients have low mean cell volume (MCV) of red blood cells too.

People with Vitamin B12 deficiency have large red blood cells. People with folic acid deficiency also have large erythrocytes. They have a high MCV mean corpuscular volume.

Dr. Aric Parnes, MD: People with bone marrow diseases also mostly have large red blood cells. These diseases are myelodysplastic syndrome, aplastic anemia, leukemia. These patients also have large mean corpuscular volume (MCV) of erythrocytes.

Then there is a middle ground. These are patients who have anemia. But they have normal values of mean corpuscular volume (MCV) of red blood cells. Such patients often have anemia of inflammation. This anemia previously was called anemia of chronic disease.

Dr. Anton Titov, MD: Chronic kidney disease, for example, chronic renal failure, often produces this type of anemia. Kidneys produce the hormone erythropoietin. It is a signal to the bone marrow to make more blood.

This is the initial algorithm of how we find the cause of anemia. We ask what is the reticulocyte count? We look at mean corpuscular volume (MCV) of red blood cells. These two tests give us a broad idea of the cause of anemia.

Let me give you an example of using the reticulocyte count.

Dr. Aric Parnes, MD: Let's say that somebody is anemic. Their reticulocyte count is elevated. I immediately think, "The patient is bleeding or the patient is destroying red blood cells". Erythrocytes are being destroyed in blood vessels of the patient. Destruction of red blood cells is called hemolysis.

Often the source of bleeding can be obvious. But sometimes the cause of bleeding is difficult to find. Because blood can hide in fecal masses. Such patients with anemia should have a colonoscopy.

Dr. Anton Titov, MD: Diagnosing hidden causes of bleeding is important. Sometimes colon polyps or colon cancer tumors can shed red blood cells into fecal masses. Loss of red blood cells into the colon creates anemia.

Microscopic bleeding into the colon can be the first sign of colon cancer. It is important to identify occult blood in the feces. Because it can help to diagnose colon cancer. Occult blood can be identified by a sensitive chemical test of fecal masses.

Colonoscopy can also help to diagnose the source of intestinal bleeding.

Dr. Aric Parnes, MD: That is correct. The purpose of colonoscopy is to identify colon polyps or colon cancer. We know that colon polyps can turn into cancerous tumors. Colonoscopy is a preventative procedure to screen for colon cancer.

If colonoscopy is negative, we do upper endoscopy (fibrogastroduodenoscopy). We look for gastric ulcer, duodenal ulcer, gastritis, or another polyp. All these can be a source of bleeding and cause anemia.

Dr. Anton Titov, MD: The source of upper GI bleeding could be a rare tumor. This could be a gastrointestinal stromal tumor (GIST). Bleeding into the duodenum is often the first sign of gastrointestinal stromal tumor presence.

Dr. Aric Parnes, MD: Yes. Sometimes there's no bleeding. I want to ask this question. Is it possible that the patient's body destroys its own red blood cells?

Dr. Anton Titov, MD: Could hemolysis explain a high reticulocyte count in anemia? Hemolysis can happen for several reasons.

Dr. Aric Parnes, MD: A common cause of hemolysis is autoimmune hemolytic anemia. It happens when your immune system is making an antibody that attacks red blood cells. To confirm autoimmune hemolytic anemia, we look for products of the breakdown of red blood cells.

There are at least three laboratory test signs of erythrocyte destruction. Number one: elevated lactate dehydrogenase enzyme, LDH. Number two: elevated bilirubin. Number three: decreased haptoglobin. Haptoglobin is a "mop" that binds and removes hemoglobin from destroyed red blood cells.

A patient may have anemia and an elevated reticulocyte count.

Dr. Anton Titov, MD: It is important to decide. Is the patient bleeding? Or does hemolysis take place?

Dr. Aric Parnes, MD: Sometimes we find that a patient has a nutritional deficiency. It's easy to correct this problem by giving the patient vitamins. To treat iron deficiency anemia can be more difficult.

People often do not tolerate iron tablets. Because iron gives patients gastrointestinal upset and constipation. But we now have multiple formulations of intravenous iron. Intravenous administration of iron is very potent. It can restore iron levels in blood to normal in 15 minutes.

Iron tablets often take 6 to 12 months to work. We have medication now to treat anemia of chronic kidney disease. This is a very common cause of anemia. Kidney disease happens very often. Chronic renal insufficiency and chronic kidney failure is common.

Patients live longer, they get dialysis and kidney transplants (renal transplants). The treatment of anemia of chronic kidney disease is replacement of erythropoietin. Kidneys made enough erythropoietin before the disease. We inject erythropoietin in a syringe.

Some names of EPO formulations are Epoetin, Epogen, Procrit, Darbepoetin (also known as Aranesp). Patients with anemia of chronic disease can get erythropoietin injections weekly or monthly.

Dr. Aric Parnes, MD: Patients can get erythropoietin when they get their dialysis. The schedule of administration of erythropoietin can be adjusted also for medical necessity and for the convenience of the patient. Treatment of anemia with erythropoietin is a good method to prevent the need for blood transfusions.

Dr. Anton Titov, MD: Erythropoietin is also the first line of treatment in myelodysplastic syndrome. Myelodysplastic syndrome sometimes causes anemia.

How to find the cause of anemia? A video interview with a top expert in hematology. Two key tests for anemia are reticulocyte count and mean corpuscular volume.

How to find the cause of anemia? Two key blood tests on a complete blood count show what the cause of anemia is likely to be. How can anemia be a first sign of colon cancer? How to find the real cause of anemia? How to treat anemia of chronic disease?

A top hematology expert discusses two important blood tests to find the exact cause of anemia.