Introduction Anemia is a blood disorder characterized by a lack of red blood cells or hemoglobin, a substance in red blood cells. Anemia results if not enough normal hemoglobin or red blood cells are produced, too many red blood cells…

Introduction Anaphylaxis is a potentially life-threatening allergic reaction with rapid onset of symptoms. Anaphylaxis usually occurs in people after they are exposed to a substance they are severely allergic to such as foods, medications, and insect stings. It has been…

Introduction Anal cancer is an uncommon type of cancer. It results when cells in the anus grow abnormally and out of control. The anus is the opening at the end of the rectum through which waste products pass when you…

Introduction An allergic reaction occurs when the immune system overreacts to a normally nonthreatening substance. There are many types, causes, and symptoms of allergic reactions. Different areas of the body can be affected depending on the allergic trigger. Some allergic…

Introduction Acute stress disorder is a type of anxiety disorder that develops in some people that witness or experience a horrifying life-threatening event. Acute stress disorder causes an assortment of symptoms including re-living the event through memories and nightmares and…

Introduction Acne, commonly referred to as pimples, blemishes, and zits, is a common skin condition that most people experience at some point in life, most often as teenagers. Acne results when tiny openings in the skin become plugged. Acne is…

Introduction Arthroscopic Surgery is a procedure that allows surgeons to see, diagnose, and treat problems inside a joint.  The procedure, also called an Arthroscopy, requires only small incisions and is guided by a miniature viewing instrument or scope.  Before arthroscopy…