Hematocrit refers to the percentage of red blood cells present in the blood. It is an essential parameter used to evaluate overall health and diagnose various conditions. Hematocrit levels can vary depending on age, sex, and underlying health conditions.

In most cases, low hematocrit levels indicate anemia, a condition characterized by a decrease in the number of red blood cells or the amount of hemoglobin. However, there are several other factors that can cause low hematocrit levels besides anemia. This article explores some of the lesser-known causes of low hematocrit and the associated symptoms and treatment options.

1. Bone Marrow Disorders

Bone marrow disorders can impact the production of red blood cells, leading to low hematocrit levels.

Conditions such as aplastic anemia, myelodysplastic syndrome, and leukemia can directly affect the bone marrow’s ability to produce an adequate number of healthy red blood cells. These disorders often necessitate specialized treatment and close monitoring by a hematologist.

2. Chronic Kidney Disease

Chronic kidney disease (CKD) can cause low hematocrit levels due to the decreased production of erythropoietin, a hormone responsible for stimulating red blood cell production in the bone marrow.

As kidney function declines, levels of erythropoietin decrease, leading to anemia and subsequently low hematocrit. Treating the underlying kidney disease and addressing anemia with erythropoietin-stimulating agents or iron supplementation can help improve hematocrit levels.

3. Nutritional Deficiencies

Deficiencies in key nutrients, such as iron, vitamin B12, and folic acid, can lead to low hematocrit levels. Iron is crucial for the production of hemoglobin, while vitamin B12 and folic acid play essential roles in red blood cell formation.

Inadequate intake of these nutrients through diet or impaired absorption due to certain medical conditions can result in low hematocrit levels. Supplementation or dietary changes can help correct these deficiencies and restore hematocrit levels.

4. Chronic Inflammatory Disorders

Chronic inflammatory disorders like rheumatoid arthritis, lupus, and inflammatory bowel disease can contribute to low hematocrit levels.

Inflammation can affect the bone marrow’s ability to produce red blood cells and trigger the release of proteins that suppress red blood cell production. Proper management of the underlying inflammatory condition through medication and lifestyle modifications may help improve hematocrit levels.

5. Blood Loss

Excessive blood loss due to trauma, surgery, gastrointestinal bleeding, or menstruation can result in low hematocrit levels. When blood is lost, the body tries to compensate by diluting the remaining red blood cells, leading to a decrease in hematocrit.

Treating the underlying cause of bleeding and considering blood transfusions, iron infusions, or medication to control bleeding can help restore hematocrit levels.

6. Hormonal Imbalances

Hormonal imbalances, particularly those involving the thyroid gland, can influence hematocrit levels. Both hyperthyroidism and hypothyroidism can disrupt the production and lifespan of red blood cells, leading to low hematocrit levels.

Addressing the underlying hormonal imbalance through medication and other appropriate interventions can help restore hematocrit to normal levels.

7. Chronic Liver Disease

Chronic liver disease and cirrhosis can contribute to low hematocrit levels. Liver dysfunction affects the production of clotting factors, proteins, and other substances necessary for maintaining blood volume and composition.

Additionally, liver disease can lead to portal hypertension and increased sequestration of red blood cells in the spleen, resulting in low hematocrit. Treating the underlying liver condition and managing complications can help improve hematocrit levels.

8. Genetic Hemoglobin Disorders

Genetic disorders affecting hemoglobin structure or production, such as thalassemia and sickle cell disease, can cause low hematocrit levels.

These conditions result in abnormal or insufficient hemoglobin synthesis, leading to a decreased number of functional red blood cells. While these genetic disorders are typically lifelong, various treatment options can help manage symptoms and improve hematocrit levels.

9. Medications

Certain medications can potentially lower hematocrit levels as a side effect.

Chemotherapy drugs, immunosuppressants, antibiotics, and anticonvulsants are examples of medications that may cause a decrease in red blood cell production or increase their destruction. If a medication is suspected of causing low hematocrit, consulting a healthcare professional to explore alternative medications or potential dosage adjustments is recommended.

10. Chronic Lung Diseases

Chronic lung diseases such as chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis can contribute to low hematocrit levels. These conditions impair the exchange of oxygen and carbon dioxide in the lungs, leading to tissue hypoxia.

To compensate for reduced oxygen supply, the body produces more red blood cells, resulting in a phenomenon known as secondary polycythemia. However, this can also dilute the blood and consequently lower the hematocrit. Managing the underlying lung condition and ensuring adequate oxygen supply can help maintain optimal hematocrit levels.