Glossary (E-H)

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E

Echinococcosis, Pulmonary
Helminth infection of the lung caused by Echinococcus granulosus or Echinococcus multilocularis.

Edema
An abnormal accumulation of fluid in the tissues that causes swelling.

Elastic Recoil
The tendency of the lungs to shrink back to its resting shape with breathing out after being stretched during breathing in.

Elasticity
The ability of the alveoli to stretch and get smaller with breathing.

Electrocardiogram (ECG or EKG)
An EGG is a test used to find out if the heart rate and rhythm are normal or if heart damage has occurred. It's a graphic record of the heart's electrical impulses. When an EGG is done, several wires, or "leads," are attached to the arms, legs and chest. This is called a "12-lead EGG." It takes 12 different recordings at the same time. Each lead records the same electrical impulse, but from a different position in relation to the heart.

Electrocautery
A probe heated to a high temperature to destroy the tumor or granulation/scar tissue and also control bleeding by cauterizing/desiccating (drying) the tissue.

Emphysema
Emphysema involves a gradual destruction of the alveoli (the grapelike clusters of air sacs that a line the ends of bronchioles). The walls of the alveoli become inflamed and lose elasticity. Rather than nice clusters of grapes, larger pockets of dead air (called bullae) form. These bullae impair the ability to exchange oxygen and carbon dioxide. In addition, the ability to exhale normally is impaired and the lungs become hyperinflated. Because the ability to inhale is not impaired, oxygen and carbon dioxide levels in the blood are normal until the late stages of the disease.

  • Symptoms of emphysema include:
  • Shortness of breath with light exertion, minor coughing and minimal sputum production in early stages.
  • Rapid and labored breathing, persistent shortness of breath with minimal activity or at rest in late stages
  • Barrel-shaped chests from over inflated lungs (hyperinflation) due to air trapping
  • Pinkish tinge to skin
  • Involuntary weight loss

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Empyema, Pleural
Suppurative inflammation of the pleural space.

Empyema, Tuberculous
Empyema due to mycobacterium tuberculosis.

Encephalomyelitis, Allergic
An experimental demyelinating disease produced in animals by injections of myelin fractions in order to study the relationship between hypersensitivity and the demyelinating diseases.

End-Stage Emphysema
When emphysema has reached the stage where symptoms severely affect the quality of life.

Endobronchial Ultrasound System (EBUS)
EBUS allows us to see the vital structures, such as large blood vessels, around the airways and makes biopsy of abnormal tissue around the airways safe and efficient by avoiding blood vessels. It’s the same ultrasound technology that has been used for decades to examine the unborn child in a mother’s womb. Now it’s miniaturized into a very small device that can either pass thru the bronchoscope or is attached to it.

Endothelium, Lymphatic
Unbroken cellular lining (intima) of the lymph vessels (e.g., the high endothelial lymphatic venules). It is
more permeable than vascular endothelium, lacking selective absorption and functioning mainly to remove plasma proteins that have filtered through the capillaries into the tissue spaces.

Endotracheal tube (ET)
Endotracheal tubes are used to connect a patient to a respirator, it's inserted through the patient's mouth or nose, passes through the throat (and vocal cords), and into the air passages. The patient will be unable to speak while the tube is in place.

Endurance
Exercise to increase your ability to sustain an activity.

Enterochromaffin Cells
Group of basal granular cells of the gut whose granules stain readily with silver and chromium salts. The cells secrete serotonin, substance P, and enkephalins. There are three types: gastric (antral mucosa), duodenal, and intestinal.

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Environmental Illness
A polysymptomatic condition believed by clinical ecologists to result from immune dysregulation induced by common foods, allergens, and chemicals, resulting in various physical and mental disorders. The medical community has remained largely skeptical of the existence of this "disease," given the plethora of symptoms attributed to environmental illness, the lack of reproducible laboratory abnormalities, and the use of unproven therapies to treat the condition. (From Segen, Dictionary of Modern Medicine, 1992)

Enzootic Bovine Leukosis
A lymphoid neoplastic disease in cattle caused by the bovine leukemia virus. Enzootic bovine leukosis may take the form of lymphosarcoma, malignant lymphoma, or leukemia, but the presence of malignant cells in the blood is not a consistent finding.

Eosinophils
Granular leukocytes with a nucleus that usually has two lobes connected by a slender thread of chromatin, and cytoplasm containing coarse, round granules that are uniform in size and stainable by eosin.

Epidermal Necrolysis, Toxic
An exfoliative disease of skin seen primarily in adults and characterized by flaccid bullae and spreading erythema so that the skin has the appearance of being scalded. It results primarily from a toxic reaction to various drugs, but occasionally occurs as a result of infection, neoplastic conditions, or other exposure.

Epiglottis
Thin leaf-shaped cartilage, covered with mucous membrane, at the root of the tongue, which folds back over the entrance to the larynx, covering it during the act of swallowing.

Epiglottitis
Inflammation of the epiglottis.

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Epistaxis
Bleeding from the nose. It may be caused by a manifestation of a general disease, as in the early stages of acute fevers, from a local disease of the nasal passages, or from high blood pressure.

Epithelioid Cells
Characteristic cells of granulomatous hypersensitivity. They appear as large, flattened cells with Increased endoplasmic reticulum. They are believed to be activated macrophages that have differentiated as a result of prolonged antigenic stimulation. Further differentiation or fusion of epithelioid cells is thought to produce multinucleated giant cells (GIANT CELLS).

Erythema Nodosum
An erythematous eruption commonly associated with drug reactions or infection and characterized by inflammatory nodules that are usually tender, multiple, and bilateral. These nodules are located predominantly on the shins with less common occurrence on the thighs and forearms. They undergo characteristic color changes ending in temporary bruise-like areas. This condition usually subsides in three to six weeks without scarring or atrophy.

Erythroblastosis, Fetal
Hemolytic anemia of the fetus or newborn infant, caused by the transplacental transmission of maternally formed antibody, usually secondary to an incompatibility between the blood group of the mother and that of her offspring. (From Dorland, 27th ed)

Esophagus
The tube that connects the mouth and stomach.

Ethmoid Sinus
Numerous small thin-walled spaces or air cells in the ethmoid bone, where they form an ethmoidal labyrinth.

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Ethmoid Sinusitis
Inflammation of the ethmoid sinus. It may present itself as an acute (associated with viral rhinitis) or chronic (associated with allergic or hyperplastic sinusitis) condition.

Exacerbation
An episode when a disease or medical condition gets worse. In COPD, exacerbations are due to bacterial or viral infections and can cause signs and symptoms such as increased coughing, increased sputum (phlegm), and a change in the color of sputum and fever.

Expiration
The act of breathing air out of the lungs (also called exhalation). This is usually a passive activity. As the respiratory muscles relax, air is expelled from the lungs. In COPD, expiration requires effort to push the trapped air out of the lungs.

Expiratory Reserve Volume (ERV)
Expiratory reserve volume is the maximum amount of air that can be breathed out at the end of a normal (quiet) expiration or the extra amount of air that can be breathed out at the end of a normal expiration.

Extravascular Lung Water
Water present within the lungs; its volume is roughly equal to, or a little less than, the intracellular blood volume of the lungs. Accumulations of extravascular lung water result in pulmonary edema.

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F

Farmer's Lung
Systemic and pulmonary reactions resulting from inhalation of dust from moldy hay, threshing dust, or moldy straw, by persons who have become hypersensitive to antigens in the dust. It is most often associated with inhalation of spores of Micromonospora faeni or Thermoactinomyces vulgaris. (From Dorland, 27th ed)

Fatigue
Feeling weak or tired.

FEF
Please see, "Forced Expiratory Flow".

Felty's Syndrome
A combination of rheumatoid arthritis, splenomegaly, leukopenia, pigmented spots on lower extremities, and other evidence of hypersplenism (anemia and thrombocytopenia). (From Dorland, 27th ed)

FEV1
Please see, "Forced Expiratory Volume in 1 Second",

FEV1/FVC
The amount of air that can be forcibly breathed out in one second (FEV1) divided by the total amount of air that can be breathed out (forced vital capacity or FVC); this result is important in diagnosing COPD.

Fibrosis
An abnormal formation of fibrous tissue. In the lungs this represents a progressive condition that involves the walls of the alveoli and is associated with chronic inflammation and steadily increasing respiration dysfunction.

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Flexible Bronchoscopy
A black, soft, rubber tube-like instrument which carries a camera, light and working channel. This instrument can turn and twist to negotiate contours of human airways. It allows doctors to look inside the airways, take pictures of abnormal areas and obtain sample-like brushings, washings and biopsies.

Flexibility
Exercise to stretch muscles, increasing bloodflow to the muscle.

Fluoroscopy
An x-ray that captures images of body structures in motion.

Foam Cells
Lipid-laden macrophages originating from monocytes or from smooth muscle cells.

Food Hypersensitivity
Gastrointestinal disturbances, skin eruptions, or shock due to allergic reactions to allergens ingested in food.

Foreign Invaders
Bacteria, viruses, fungi, and other substances that are foreign to the body.

Forced Expiratory Volume in 1 Second (FEV1)
Forced expiratory volume in one second is the maximum amount of air that can be breathed out in the first second during a forced expiration test. This is an important value in both the diagnosis and management of COPD.

Forced Expiratory Flow (FEF)
A measurement of the flow of how much air can be breathed out from the lungs.

Forced Vital Capacity (FVC)
After taking in as deep a breath as possible, the air is breathed out as forcibly as possible until no more can be breathed out. This gives an indication of the size of the lungs, how compliant (elastic) they are and how well the air passages open and close.

Frequency
How often to do an activity.

FRC
See "Functional Residual Capacity".

Frontal Sinus
One of the paired, but seldom symmetrical, air spaces located between the inner and outer compact layers of the frontal bone.

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Frontal Sinusitis
Inflammation of the frontal sinus; in most cases the infection is caused by the bacteria streptococcus pneumoniae and haemophilus influenzae. This condition may be acute or chronic.

Functional Residual Capacity (FRC)
Functional Residual Capacity also known as FRC, is the amount of air in the lungs at the end of a normal (quiet) expiration (when the muscles of respiration are completely relaxed). At FRC, the tendency of the lungs to collapse is exactly balanced by the tendency of the chest wall to expand.

Fungus (fungi is the plural form)
Primitive organisms that can cause disease.

FVC
See "Forced Vital Capacity"

G

Gamma Interferon
Helps fight infection and boosts the function of phagocytes.

Gamma globulin
An antibody. Also called immune globulin.

Gene Therapy
Genes are the basic units of heredity. Researchers are working to clone or reproduce different genes that can treat diseases like immune deficiencies.

Germinal Center
The area in the center of a lymph node containing aggregations of actively proliferating lymphocytes (antibody-forming B cells). It appears as a spherical mass surrounded by a capsule of elongated cells that is partially invested by a crescentic cap of small lymphocytes. Germinal centers are also found in the spleen, thymus, and chicken caecal tonsil. (From Dorland, 28th ed)

Giant Cells, Foreign-Body

Multinucleated cells (fused macrophages), characteristic of granulomatous inflammation, which form around exogenous material in the skin. They are similar in appearance to Langhans giant cells (GIANT CELLS, LANGHANS), but foreign-body giant cells have more abundant chromatin and their nuclei are scattered in an irregular pattern in the cytoplasm.

Giant Cells, Langhans
Multinucleated cells (fused macrophages) seen in granulomatous inflammations such as tuberculosis,
syphilis, sarcoidosis, and deep fungal infections. They resemble foreign-body giant cells (GIANT CELLS, FOREIGN BODY), but Langhans giant cells contain less chromatin and their nuclei are arranged peripherally in a horseshoe-shaped pattern. Langhans giant cells occur frequently in delayed hypersensitivity.

Giant Lymph Node Hyperplasia
Large benign, hyperplastic lymph nodes. The more common hyaline vascular subtype is characterized by small hyaline vascular follicles and interfollicular capillary proliferations. Plasma cells are often present and represent another subtype with the plasma cells containing IgM and IgA.

Glomerulonephritis, IGA
Chronic form of glomerulonephritis characterized by recurring hematuria with only slight proteinuria and by deposits of IGA immunoglobulin in the mesangial areas of the renal glomeruli. It usually occurs in young males.

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Glomerulonephritis, Membranoproliferative
Chronic glomerulonephritis characterized histologically by proliferation of mesangial cells, increase in the mesangial matrix, and a thickening of the glomerular capillary walls. The wall thickening is sometimes said to be a result of the interposition of mesangial cytoplasm or matrix between the basement membrane and the endothelium of the capillary wall. It is often divided into types I and II, and sometimes III. Pathogenesis is not well understood, but some types are thought to involve the immune system, with the complement system, in particular, being implicated.

Glomerulonephritis, Membranous
A disease of the glomerulus manifested clinically by proteinuria, and sometimes by other features of the nephrotic syndrome. It is histologically characterized by deposits in the glomerular capillary wall between the epithelial cell and the basement membrane and a thickening of the membrane. Also characteristic are outward projections of the membrane between the epithelial deposits in the form of "spikes." There is some agreement that the deposits are antigen-antibody complexes.

Glottis
The vocal apparatus of the larynx, consisting of the true vocal cords (plica vocalis) and the opening between them (rima glottidis).

Goblet Cells
Cells of the epithelial lining that produce and secrete mucins.

Goodpasture Syndrome
A combination of pulmonary hemorrhage and glomerulonephritis. It is known also as the lung purpura glomerulonephritis complex. It is considered by some to be a form of hypersensitivity reaction.

Graft vs. Host Disease
The clinical entity characterized by anorexia, diarrhea, loss of hair, leukopenia, thrombocytopenia, growth retardation, and eventual death brought about by the graft vs. host reaction.

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Granulocytes
Leukocytes with abundant granules in the cytoplasm. They are divided into three groups: NEUTROPHILS, EOSINOPHILS, and BASOPHILS.

Granuloma, Laryngeal

A polypoid granulomatous projection into the lumen of the larynx.

Granuloma, Lethal Midline
A non-neoplastic disease of unknown etiology beginning with inflammation, ulceration, and perforation of nose and palate and progressing to gradual destruction of midline facial structures.

Granuloma, Plasma Cell, Pulmonary
A pseudotumor of the lung composed of inflammatory cells and showing complete maturity of fibroblastic components with a striking lack of mitosis. It is also called postinflammatory pseudotumor and
pseudoneoplastic pneumonitis. (Berardi, R.S. et al. Inflammatory pseudotumors of the lung. Surg Gynecol Obstet 156:89-96, Jan 83)

Granulomatous Disease, Chronic
A recessive X-linked defect of leukocyte function in which phagocytic cells ingest but fail to digest bacteria, resulting in recurring bacterial infections with granuloma formation.

Graves' Disease
Hyperthyroidism associated with a diffuse hyperplastic goiter resulting from production of an antibody directed against the thyroid-stimulating hormone (TSH) receptor, which acts as an agonist of TSH. (Braverman, The Thyroid, 6th ed, p648)

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H

Hantavirus Pulmonary Syndrome
Acute respiratory illness in humans caused by the Muerto Canyon virus whose primary rodent reservoir is the deer mouse peromyscus maniculatus. First identified in the southwestern United States, this syndrome is characterized most commonly by fever, myalgias, headache, cough, and rapid respiratory failure.

Hay Fever
A seasonal variety of allergic rhinitis, marked by acute conjunctivitis with lacrimation and itching, regarded as an allergic condition triggered by specific allergens.

Heavy Chain Disease
A disorder of immunoglobulin synthesis in which large quantities of abnormal heavy chains are excreted in the urine. The amino acid sequences of the N- (amino-) terminal regions of these chains are normal, but they have a deletion extending from part of the variable domain through the first domain of the constant region, so that they cannot form cross-links to the light chains. The defect arises through faulty coupling of the variable (V) and constant (C) region genes.

Hemopneumothorax
Accumulation of air and blood in the pleural cavity. (Stedman, 25th ed)

Hemoptysis
Expectoration of blood or blood-stained sputum. (Dorland, 27th ed)

Hemothorax
A collection of blood in the pleural cavity. (Dorland, 27th ed)

Hepatitis
Inflammation or swelling of the liver. There are many causes including several different hepatitis viruses.

Histiocytes
A type of macrophage. (Dorland, 28th ed)

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Histiocytosis, Langerhans Cell
Group of disorders of histiocyte proliferation which includes Letterer-Siwe Disease, Hand-Schueller-Christian Syndrome, and eosinophilic granuloma. Langerhans cells are components of the lesions.

HIV
Human immunodeficiency virus. A virus that is found in the blood and other body secretions of an infected person.

HIV Enteropathy
Chronic, well-established diarrhea (greater than one month in duration) without an identified infectious cause after thorough evaluation, in an HIV-positive individual. It is thought to be due to direct or indirect effects of HIV on the enteric mucosa. HIV enteropathy is a diagnosis of exclusion and can be made only after other forms of diarrheal illness have been ruled out. (Harrison's Principles of Internal Medicine, 13th ed, pp1607 -8; Haubrich et al., Bockus Gastroenterology, 5th ed, p1155)

HIV Infections
Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, to AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).

HIV Seropositivity
Development of neutralizing antibodies in individuals who have been exposed to the human immunodeficiency virus (HIV/HTLV-III/LAV).

HIV Wasting Syndrome
Involuntary weight loss of greater than 10 percent associated with intermittent or constant fever and chronic diarrhea or fatigue for more than 30 days in the absence of a defined cause other than HIV infection. A constant feature is major muscle wasting with scattered myofiber degeneration. A variety of etiologies, which vary among patients, contributes to this syndrome. (From Harrison's Principles of Internal Medicine, 13th ed, p1611).

Hoarseness
An unnaturally deep or rough quality of voice.

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Hodgkin Disease
A malignant disease characterized by progressive enlargement of the lymph nodes, spleen, and general
lymphoid tissue, and the presence of large, usually multinucleate, cells (Reed-Sternberg cells) of unknown origin.

Hormone
A substance that is produced by a gland and carried by the bloodstream to cause an effect somewhere else in the body. The nervous system controls the production of hormones.

HTLV-BLV Infections
Infections caused by the HTLV or BLV retroviruses. They include human T-cell leukemia-lymphoma and adult T -cell leukemia.

Hyaline Membrane Disease
A disorder affecting newborn infants (usually premature) characterized pathologically by the development of a hyaline-like membrane lining the terminal respiratory passages. Extensive atelectasis is attributed to the lack of surfactant. (Dorland, 27th ed)

Hydropneumothorax
A collection of fluid and gas within the pleural cavity. (Dorland, 27th ed)

Hydrops Fetalis
Edema of the entire body due to abnormal accumulation of serous fluid in the tissues, associated with severe anemia and occurring in ERYTHROBLASTOSIS, FETAL.

Hydrothorax
A collection of watery fluid in the pleural cavity. (Dorland, 27th ed)

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Hypercapnia
A condition marked by an unusually high concentration of carbon dioxide in the blood (CO2 is greater than 45 mmHg) as a result of slow and/or shallow respirations (hypoventilation). Symptoms include increased respiratory rate, headache, confusion, lethargy, nausea and/or vomiting.

Hypergammaglobulinemia
An excess of gamma-globulins in the blood. It is seen frequently in chronic infectious diseases. (Dorland, 27th ed)

Hypersensitivity
Altered reactivity to an antigen, which can result in pathologic reactions upon subsequent exposure to that particular antigen.

Hypersensitivity, Delayed
An increased reactivity to specific antigens mediated not by antibodies but by cells.

Hypersensitivity, Immediate
Hypersensitivity reactions which occur within minutes of exposure to challenging antigen. Due to the release of histamine which follows the antigen-antibody reaction and causes smooth muscle contraction and increased vascular permeability.

Hyperventilation
When a person hyperventilates the breathing rate is fast and each breath is deep. This abnormal type of breathing causes more oxygen (02) to be breathed in (inspired) and decreases the amount of carbon dioxide (CO2) in the blood.

Hypogammaglobulinemia

Lower than normal levels of immunoglobulins (or anti-bodies) in the blood.

Hypoventilation
When a person hypoventilates, the respiratory rate is slow and each breath is shallow. This abnormal type of breathing causes decreased amounts or oxygen (02) to be breathed in (inspired) and high levels of carbon dioxide (CO2) to accumulate in the blood.

Hypoxemia
Inadequate oxygenation of the blood (oxygen in the blood (Pa02) is less than 55 mmHg or saturation of oxygen (Sa02) is less than 85%). Symptoms of hypoxemia include fast heart rate, anxiety, agitation forgetfulness, inability to concentrate, and changes in levels of consciousness.

Hypoxia
Oxygen is needed by all tissues in the body to do the work each is designed to do. Hypoxia exists when an inadequate or deficient amount of oxygen reaches the tissues.

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