Final answer:
Increased numbers of basophils are typically associated with allergic reactions, where they play a crucial role in the body's immune and inflammatory responses, notably by releasing histamines.
Step-by-step explanation:
Increased numbers of basophils are often associated with certain medical conditions due to their role in the body's immune response. These white blood cells are known for intensifying the inflammatory response and are involved in the defense against parasites and allergic reactions. The granules of basophils release histamines, which contribute to inflammation, and heparin, which opposes blood clotting. When considering the conditions listed, basophils are notably increased in instances of allergic reactions. Allergies are characterized by a hypersensitivity of the immune system to substances that are generally harmless, resulting in symptoms like sneezing, itchiness, and red eyes.
An increased basophil count is typically associated with type I hypersensitivity reactions, such as allergic asthma, hay fever, and other allergies, whereby exposure to allergens triggers an antibody-mediated immune response. Upon secondary exposure to an allergen, mast cells with IgE antibodies bound to their surfaces react by releasing histamines and other inflammatory molecules, exacerbating the symptoms of allergy.