echolalia The involuntary, parrot-like repetition (echoing) of a word or phrase just spoken by another person. Echolalia is a feature of schizophrenia (especially the catatonic form), Tourette syndrome, and other disorders. See also echopraxia; schizophrenia; Tourette syndrome.
echopraxia The involuntary imitation of the movements of another person. Echopraxia is a feature of schizophrenia (especially the catatonic form), Tourette syndrome, and some other neurologic diseases. See also echolalia.
echovirus A group of viruses found in the intestinal tract. The “echo” part of the name is an acronym for enteric cytopathic human orphan viruses. “Orphan” implied that these viruses were not associated with any disease. However, it is now known that echoviruses can cause a number of different diseases, including rashes, diarrhea, respiratory infections…
eclampsia The presence of one or more convulsions in a pregnant woman who has preeclampsia. Eclampsia is a frequent cause of maternal death in underdeveloped countries, and it is a serious problem even in developed countries. Treatment is with antispasmodic medication, notably magnesium sulfate. See also HELLP syndrome; preeclampsia.
ecogenetics The interaction of genetics with the environment. For example, persons with the genetic disease phenylketonuria (PKU) lack an enzyme that is needed to process the amino acid phenylalanine, and they require a special environment: a diet low in phenylalanine.
dystonia musculorum deformans See dystonia, torsion.
dystrophy, muscular See muscular dystrophy.
dystrophy, myotonic A relatively common inherited disease in which the muscles contract but have decreasing ability to relax (myotonia). Myotonic dystrophy is also characterized by the development of a mask-like, expressionless face, premature balding, cataracts, and abnormalities in heart rhythm. See amplification; anticipation.
dysuria Pain during urination, or difficulty urinating. Dysuria is usually caused by inflammation of the urethra, frequently as a result of infection.
E. coli Escherichia coli, a bacterium that normally resides in the colon. Although E. coli is normally present in the colon with no harmful consequences, it can cause disease when transmitted from human to human via water, food, or feces. Infants, young children, the elderly, and people with compromised immune systems are especially at risk…
Eagle syndrome Inflammation of the styloid process, a spike-like growth that projects out of the base of the skull. If the styloid process is oversized or projects too far, the tissues in the throat can rub on it causing pain during the act of swallowing and pain on rotation of the neck. Diagnosis of Eagle…
ear The hearing organ. There are three sections of the ear: outer, middle, and inner. The outer, or external, ear helps concentrate the vibrations of air created by sound onto the eardrum, causing the eardrum to vibrate. These vibrations are transmitted by a chain of little bones in the middle ear to the inner ear,…