A red blood cell count (RBC) measures the number of blood cells contained per cubic milliliter of blood. Doctors order RBC counts for a variety of reasons such as for a physical, to monitor chemotherapy and to examine the effects of conditions including hemophilia, anemia and lung diseases such as asthma.
RBC counts indicate normal levels and increases or decreases in red blood cells, giving doctors insight to diagnose and treat potential conditions or understand the body’s response to medicine and therapy. According to the Leukemia and Lymphoma Society, average adult red blood cell counts are between 4 to 5 million per microliter of blood in adult females and 4.5 to 6 million per microliter in adult males. Diseases such as asthma affect red blood cell counts through increases.
Asthma is a chronic inflammatory disease of the lungs. Allergic asthma is triggered by the inhalation of allergens such as pet dander, dust mites and pollen versus non-allergic asthma which is exacerbated by weather changes, exercise, emotional stress and environmental irritants. Both forms inflame the airways, causing swelling and irritation that constricts breathing, leading to a number of symptoms.
People with asthma experience narrowing of the breathing tubes, allowing less air to reach the lungs. This reaction leads to pulmonary stress and symptoms of wheezing, coughing, chest tightness, shortness of breath and asthma attacks. Asthma results in low oxygen levels and decreased lung function, which affects the rate at which red blood cells deliver oxygen to the lungs.
Red blood cells are produced in the bone marrow and function to carry oxygen from the lungs to the body’s tissues and carbon dioxide from the tissues to the lungs. RBC counts of individuals with asthma are likely to indicate increased red blood cell levels because the inflamed and narrowed airways decrease air flow, allowing less oxygen to reach the lungs. Asthma limits the oxygen-carrying capacity of red blood cells, so the body compensates by producing more red blood cells in an effort to transport oxygen to the lungs; hence elevating red blood cell levels.
Increases in red blood cells can be asymptomatic or can lead to symptoms of disorientation, fatigue, distorted vision and blotchy skin. Treating asthma by eliminating exposure to triggers and taking medications such as oral or inhaled corticosteroids, beta-antagonists and antihistamines results in relief of symptoms and a decreased RBC count.