Dictionary

allergic salute The characteristic gesture of a person with allergic rhinitis: rubbing his or her nose with the index finger.

allergic rhinitis, seasonal Allergic rhinitis that occurs during a specific season.

allergic rhinitis, perennial Allergic rhinitis that occurs throughout the year.

allergic rhinitis Medical term for hay fever, an allergic reaction that mimics a chronic cold. Symptoms include nasal congestion, a clear runny nose, sneezing, nose and eye itching, and tearing of the eyes. Postnasal dripping of clear mucus frequently causes a cough, loss of smell is common, and occasionally loss of taste. Nosebleeds may occur….

allergic reaction A hypersensitive immune response to a substance. An allergic reaction can occur when the immune system attacks a normally harmless substance. The allergic immune system calls upon a protective antibody called immunoglobulin E (IgE) to fight these invading substances. In the melee, cells called mast cells release a variety of strong chemicals, including…

allergic granulomatosis See Churg-Strauss syndrome.

allergic conjunctivitis Inflammation of the whites of the eyes (conjunctivae), with itching, redness, and tearing, due to allergy.

allergen A substance that can cause an allergic reaction. Common allergens include ragweed pollen, animal dander, and mold.

allele An alternative form of a gene.

alkaptonuria A genetic metabolic disorder due to deficiency of the enzyme homogentisic acid (HGA) dioxygenase. Deficiency of this enzyme leads to the three cardinal features of alkaptonuria (the presence of homogentisic acid in the urine), ochronosis (bluish-black pigmentation in connective tissue), and arthritis. Urine that turns dark is a characteristic feature.

alkalosis Relatively too much base in the blood and body, an abnormal condition resulting from the accumulation of base or the depletion of acid. The pH of an alkalotic body measures above normal. The opposite of alkalosis is acidosis.

alkaline phosphatase An enzyme that liberates phosphate under alkaline conditions and is made in liver, bone, and other tissues. Alkaline phosphatase can be measured in a routine blood test. Abnormally high serum levels of alkaline phosphatase may indicate bone disease, liver disease, or bile duct obstruction.