A-H 4

Extraction ratio

Fraction of the drug entering the liver in the blood which is irreversibly removed.

Extrapyramidal symptoms (EPS)

Adverse drug effects of medications such as phenothiazines. H include dystonia (involuntary muscle contractions), tardive dyskinesia (repetitive, involuntary movements), and akathisia (motor restlessness or anxiety).

Extravasation

Movement of fluid from inside a blood vessel into the surrounding tissues.

Facultative

An optional biological condition, not required for growth or survival.

Felty syndrome

An extra-articular manifestation of rheumatoid arthritis associated with splenomegaly and neutropenia.

Ferritin

A protein that binds iron; most of the iron stored in the body is bound to ferritin.

Festination

Walking with short, rapid, shuffling steps.

Fibrin

An insoluble protein that is one of the principal ingredients of a blood clot. Fibrin strands bind to one another to form a fibrin mesh. The fibrin mesh often traps platelets and other blood cells.

Fibrinolysis

The process that dissolves fibrin and removes small blood clots. Hydrolysis of Fibrin

Fibroadenoma

A benign neoplasm occurring in breast tissue derived from glandular epithelium.

Fibrosis

Development of fibrous connective tissue in response to injury or damage.

Fluorescence in situ hybridization (FISH)

A laboratory technique used to look at genes or chromosomes in cells and tissues. Pieces of DNA that contain a fluorescent dye are made in the laboratory and added to cells or tissues on a glass slide. When these pieces of DNA bind to specific genes or areas of chromosomes on the slide, they light up when viewed under a

Fistula

Abnormal connection between two internal organs (eg, arteriovenous fistula is a connection between an artery and a vein), or between an internal organ and the exterior or skin (eg, enterocutaneous fistula is a connection between the intestine and the skin).

Fistulogram

An X-ray photograph taken after the injection of contrast material or radiopaque material.

Flexural psoriasis

Psoriasis characterized by lesions found in skin folds. These lesions tend to be erythematous plaques and are often found in the axillary, genital, perineal, intergluteal, and inframammary regions. While shiny, smooth, and deep red in color there may be skin fissures and the absence of the silvery scales

Flight of ideas

A nearly continuous flow of rapid speech and thought that jumps from topic to topic, usually loosely connected.

Floppy iris syndrome

A syndrome of pupillary constriction, flaccid iris, and iris prolapse which can result in intraoperative complications during cataract surgery; associated with use of an α1 adrenergic antagonist (eg, tamsulosin).

Flow cytometry

A method of measuring the number of cells in a sample, the percentage of live cells in a sample, and certain characteristics of cells, such as size, shape, and the presence of tumor markers on the cell surface. The cells are stained with a light-sensitive dye, placed in a fluid, and passed in a stream before a laser or other type of light. The measurements are based on how the light-sensitive dye reacts to the light.

Foam cell

A lipid-laden white blood cell.

Focal seizures

Seizures that start in a small area of the brain and may spread.

Forced expiratory volume in the first second (FEV1)

The volume of air that a patient can forcibly exhale in the first second of forced exhalation after taking a maximal breath..

Forced vital capacity

The maximum volume of air forcibly exhaled after taking a maximal breath.

Fraction of exhaled nitric oxide (FeNO)

A noninvasive test indicating inflammation in the airways when elevated.

Fragility fracture

A fracture from a fall from standing height or less amount of trauma

Frailty

Excess demand imposed upon reduced capacity, a syndrome common in the elderly.

Frank-Starling mechanism

Increase in stroke volume in response to an increase in volume of blood filling the heart (ie, end diastolic volume) when all other factors remain constant.

Freezing

A sudden but temporary inability to move.

Fremitus

Vibrations through the chest wall that may be detected through touch (tactile) or heard (vocal) through a stethoscope with certain spoken words (eg, “ninety-nine”).

French scale

Scale used to measure external diameter of a feeding tube.

Fructooligosaccharide

Soluble fiber fermented by colonic bacteria to short-chain fatty acids.

Gadolinium

An intravenous contrast agent used in magnetic resonance imaging.

Gallstone (cholelithiasis)

A solid formation in the gallbladder or bile duct composed of cholesterol and bile salts.

γ-Aminobutyric acid (GABA)

An inhibitory neurotransmitter.

Gamma knife

A radiosurgery machine that focuses low-dosage gamma radiation on a precise target.

Gastric bypass

A surgical procedure for weight loss that elicits its effectiveness through malabsorption and gastric volume limitation. The procedure involves full partitioning of the proximal gastric segment into a jejunal loop.

Gastritis

Inflammation of the stomach lining.

Gastroparesis

A form of autonomic neuropathy involving nerves of the stomach. It may include nausea, vomiting, feeling full, bloating and lack of appetite. It may cause wide fluctuations in blood sugars due to insulin action and nutrient delivery not occurring at the same time.

Gastrostomy

Operative placement of a new opening into the stomach associated with feeding tube placement.

Generalized seizures

Seizures where the entire cerebral cortex is involved from the onset.

Geniculate nucleus

The portion of the brain that processes visual information from the optic nerve and relays it to the cerebral cortex.

Genotype

The genetic constitution of an individual.

Geriatric syndrome

Age-specific presentations or differential diagnoses, including visual and hearing impairment, malnutrition and weight loss, urinary incontinence, gait impairment and falls, osteoporosis, dementia, delirium, sleep problems, and pressure ulcers; commonly seen conditions in older patients..

Gleason score

System of histological grading used in prostate cancer. Individual scores range from 2 to 5. The two highest scores from each sample are combined for a total score (up to 10). Higher scores indicate higher grade and more aggressive tumor.

Glomerular filtration rate (GFR)

The volume of plasma that is filtered by the glomeruli per unit time, usually expressed as mL/min or mL/min/1.73 m2 (and in some areas in SI units of mL/s or mL/s/m2), which adjusts the value for body surface area. This is the primary index used to describe overall renal function.

Glomerulonephritis

Glomerular lesions that are characterized by inflammation of the capillary loops of the glomerulus. These lesions are generally caused by immunologic, vascular, or idiopathic diseases and lead to high blood pressure and possible loss of kidney function.

Glucagon

A hormone that raises blood glucose levels by promoting glycogen breakdown in the liver.

Gluconeogenesis

Formation of glucose from precursors other than carbohydrates especially by the liver and kidney using amino acids from proteins, glycerol from fats, or lactate produced by muscle during anaerobic glycolysis

Glucosuria

Presence of glucose in the urine.

Glutamate

An excitatory amino acid found in the central nervous system.

Glycogenolysis

The process of breaking down glycogen into glucose.

Goiter

Enlargement of the thyroid gland causing a neck swelling.

Gonioscopy

Examination of the anterior chamber angle. A gonioprism or Goldman lens is used to perform gonioscopic evaluation.

Graft-versus-host disease

A condition where donor immune cells attack the normal tissue of a hematopoietic stem celltransplant recipient.

Graft-versus-tumor effect

An immune response directed at a patient’s malignant cells by donor immune cells.

Grandiosity

An exaggerated sense of self-importance, ideas, or abilities.

Granuloma

An organized collection of macrophages attempting to wall off a foreign body or pathogen that cannot be eliminated

Gummatous

A small, soft swelling that is characteristic of the late stages of syphilis and generally occurs in the connective tissue of the liver, brain, testes, and heart.

Gut-associated lymphoid tissue

Lymphoid tissue, including Peyer patches, found in the gut that are important for providing localized immunity to pathogens.

Guttate psoriasis

Characterized by a heavy or light sprinkling of teardrop-like, salmon-pink papules covered with a fine scale. These lesions are found primarily on the trunk and proximal extremities.

Gynecomastia

Excessive development of the breasts in males.

HACEK

A group of fastidious gram-negative bacteria including Haemophilus and others.

Hashimoto Disease

Condition in which the immune system attacks the thyroid gland; may result in hypothyroidism. Symptoms may include fatigue, weight gain, pale or puffy face, feeling cold, joint and muscle pain, constipation, dry and thinning hair, heavy menstrual flow or irregular periods, depression, a slowed heart rate, and problems getting pregnant and maintaining pregnancy. It occurs more commonly in women than in men.

Health literacy

Degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions.

Heberden nodes

Hard, bony enlargement of the distal interphalangeal (terminal) joint of a finger or toe

Hematemesis

Vomiting blood from gastric or esophageal bleeding; in cirrhosis this is caused by variceal bleeding.

Hematochezia

Passage of bright red or maroon stool, usually from lower gastrointestinal bleeding.

Hematogenous

Spread of infection via the bloodstream.

Hematoma

A localized swelling in an organ or soft tissue that is filled with clotted or partially clotted blood resulting from a break in a blood vessel wall

Hemiparesis

Weakness on one side of the body.

Hemisensory deficit

Loss of sensation on one side of the body.

Hemithorax

A single side of the trunk between the neck and the abdomen in which the heart and lungs are situated.

Hemoptysis

The expectoration of blood or blood-tinged sputum from the larynx, trachea, bronchi, or lungs.

Heparin-induced thrombocytopenia

A clinical syndrome of IgG antibody production against the heparin-platelet factor 4 complex occurring in approximately 1% to 5% of patients exposed to either heparin or low-molecular weight heparin. Results in excess production of thrombin, platelet aggregation, and thrombocytopenia (due to platelet clumping), often leading to venous and arterial thrombosis, amputation of extremities, and death.

Hepatic encephalopathy

Confusion and disorientation experienced by patients with advanced liver disease due to accumulation of ammonia in the bloodstream

Hepatic steatosis

Fat accumulation in the liver.

Hepatocellular carcinoma

Cancer of the liver.

Hepatorenal syndrome

Acute kidney injury occurring in individuals with disease of the liver or biliary tract due to decreased renal blood flow and conditions that damage both organs.

Hepatotoxicity

Toxicity to the liver causing damage to liver cells.

Herd immunity

The resistance to the spread of a contagious disease within a population, if a sufficiently high proportion of the people are immune to the disease, such as through vaccination

Herniation

Abnormal protrusion of an organ or other structure through a defect or natural opening in a covering, membrane, muscle, or bone (eg, protrusion of the brain through the cranial wall).

Hesitancy

A decrease in the force of the stream of urine usually the result of an obstruction or stricture between the bladder and the external urethral orifice.

Heteroreceptor

A neuron site that binds a neurotransmitter not released by itself.

Heterotopic

Transplanting an organ into an abnormal anatomical location.

Heterozygous

Having different alleles at a gene locus.

Hiatal hernia

Protrusion of stomach through the esophageal hiatus of the diaphragm.

Hirsutism

Excessive body and facial hair, especially in females.

Histocompatibility

State of having antigenic similarities that prevent donor hematopoietic stem cells from being rejected by the recipient

Homeostenosis

Impaired capability to withstand stressors and decreased ability to maintain physiological and psychosocial homeostasis; a state commonly found in elderly