From the Guidelines
Elevated red blood cell count, or polycythemia, can result from several underlying causes, including primary polycythemia, secondary polycythemia, dehydration, certain medications, and rare genetic disorders, as outlined in the study by 1.
Causes of Polycythemia
The causes of elevated red blood cell count can be categorized into several groups, including:
- Primary polycythemia (polycythemia vera), which occurs when bone marrow produces too many red blood cells due to genetic mutations, particularly in the JAK2 gene, as discussed in the study by 1.
- Secondary polycythemia, which develops as a response to low oxygen levels in the body, and can occur in conditions like chronic lung disease, sleep apnea, smoking, heart defects, high altitude living, or kidney disease, as noted in the study by 1.
- Dehydration, which can cause a temporary increase in red blood cell concentration as blood volume decreases.
- Certain medications and supplements, including testosterone replacement therapy, erythropoietin, and anabolic steroids, which may stimulate red blood cell production, as mentioned in the study by 1.
- Rare genetic disorders that affect oxygen sensing, which can also lead to increased red blood cell production.
Diagnosis and Treatment
The body increases red blood cell production in these situations because red blood cells carry oxygen, and when oxygen levels are low or when certain genetic mutations are present, the body responds by producing more cells to improve oxygen delivery to tissues. Treatment depends on identifying and addressing the underlying cause, which may include lifestyle changes, medication adjustments, or specific treatments for primary conditions, as recommended in the study by 1. It is essential to determine the underlying cause of elevated red blood cell count to provide appropriate treatment and prevent potential complications, such as increased blood viscosity and vascular disease, as highlighted in the study by 1.
From the Research
Causes of Elevated Red Blood Count
Elevated red blood count, also known as erythrocytosis, can be caused by various factors. The following are some of the possible causes:
- Primary erythrocytosis, such as polycythemia vera (PV), a myeloproliferative neoplasm characterized by an increased red blood cell mass and increased risk of thrombosis 2, 3, 4
- Secondary erythrocytosis, which can be caused by factors such as:
- Chronic obstructive pulmonary disease (COPD) 5
- Tobacco smoking
- Sleep apnea
- Other conditions that lead to hypoxia or increased erythropoietin production
- Other causes, such as:
- Dehydration
- Blood loss
- Testosterone replacement therapy
Diagnosis and Treatment
Diagnosis of elevated red blood count involves a combination of physical examination, laboratory tests, and bone marrow biopsy. Treatment depends on the underlying cause and may include:
- Phlebotomy to reduce red blood cell mass
- Aspirin therapy to prevent thrombosis
- Cytoreductive therapy, such as hydroxyurea or interferon, to reduce red blood cell production
- Treatment of underlying conditions, such as COPD or sleep apnea
Risk Factors and Complications
Elevated red blood count can increase the risk of thrombosis, hemorrhage, and other complications. Risk factors for thrombosis include:
- Age >60 years
- History of thrombosis
- Cardiovascular risk factors
- High absolute neutrophil count
- JAK2V617F allele burden
- Abnormal karyotype
- Presence of adverse mutations, such as SRSF2, IDH2, RUNX1, and U2AF1 4