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February 10, 2012


Rash Glossary of Terms

The following are health and medical definitions of terms that appear in the Rash article.

Acne: Localized skin inflammation as a result of overactivity of the oil glands at the base of hair follicles. Acne happens when oil (sebaceous) glands come to life around puberty, when these glands are stimulated by male hormones that are produced in the adrenal glands of both boys and girls.
See the entire definition of Acne

Acyclovir: (Brand name: Zovirax) One of a group of antiviral drugs that acts against the herpes viruses, including:

  • Herpes simplex 1 which causes cold sores
  • Herpes simplex 2 which causes genital herpes
  • Varicella-zoster which causes both chickenpox and shingles
  • Epstein-Barr virus which causes infectious mononucleosis
Acyclovir inhibits the replication of viral DNA needed to reproduce itself. Virally infected cells absorb more acyclovir than normal cells and convert more of it to an active form which prolongs its antiviral activity where it is most needed. Acyclovir may reduce the severity and duration of a shingles attack if given soon after the onset of symptoms.
See the entire definition of Acyclovir

Allergy: A misguided reaction to foreign substances by the immune system, the body system of defense against foreign invaders, particularly pathogens (the agents of infection). The allergic reaction is misguided in that these foreign substances are usually harmless. The substances that trigger allergy are called allergen. Examples include pollens, dust mite, molds, danders, and certain foods. People prone to allergies are said to be allergic or atopic.
See the entire definition of Allergy

Amyloidosis: A disorder that results from the abnormal deposition of a particular protein, called amyloid, in various tissues of the body. Amyloid protein can be deposited in a localized area, and not be harmful, or in can cause serious changes in virtually any organ of the body.
See the entire definition of Amyloidosis

Antibiotic: A drug used to treat infections caused by bacteria and other microorganisms. Originally, an antibiotic was a substance produced by one microorganism that selectively inhibits the growth of another. Synthetic antibiotics, usually chemically related to natural antibiotics, have since been produced that accomplish comparable tasks.
See the entire definition of Antibiotic

Antibody: An immunoglobulin, a specialized immune protein, produced because of the introduction of an antigen into the body, and which possesses the remarkable ability to combine with the very antigen that triggered its production.
See the entire definition of Antibody

Antifungal: A drug used to treat fungal infections.
See the entire definition of Antifungal

Antihistamines: Drugs that combat the histamine released during an allergic reaction by blocking the action of the histamine on the tissue. Antihistamines do not stop the formation of histamine nor do they stop the conflict between the IgE and antigen. Therefore, antihistamines do not stop the allergic reaction but protect tissues from some of its effects. Antihistamines frequently cause mouth dryness and sleepiness. Newer "non sedating" antihistamines are generally thought to be somewhat less effective. Antihistamine side effects that very occasionally occur include urine retention in males and fast heart rate.

Antinuclear antibody: An unusual antibody that is directed against structures within the nucleus of the cell. Antinuclear antibodies (ANAs) are found in patients whose immune system is predisposed to cause inflammation against their own body tissues. Antibodies that are directed against one's own tissues are referred to as autoantibodies. The propensity for the immune system to work against its own body is referred to as autoimmunity. ANAs indicate the possible presence of autoimmunity.
See the entire definition of Antinuclear antibody

Antiviral: An agent that kills a virus or that suppresses its ability to replicate and, hence, inhibits its capability to multiply and reproduce.
See the entire definition of Antiviral

Aspergillosis: Infection with the fungus Aspergillus, seen especially in people with a deficient immune system.
See the entire definition of Aspergillosis

Atopic: Prone to allergies or characterized by allergy.

Atopic dermatitis: A skin disease characterized by areas of severe itching, redness, scaling, and loss of the surface of the skin (excoriation). When the eruption (rash) has been present for a prolonged time, chronic changes occur due to the constant scratching and rubbing known as lichenification (thickening of the skin with accentuation of the skin lines to form a crisscross pattern).
See the entire definition of Atopic dermatitis

Atypical: Not typical, not usual, not normal, abnormal. Atypical is often used to refer to the appearance of precancerous or cancerous cells.

Autoimmune: Pertaining to autoimmunity, a misdirected immune response that occurs when the immune system goes awry and attacks the body itself.
See the entire definition of Autoimmune back to top

Bacteria: Single-celled microorganisms which can exist either as independent (free-living) organisms or as parasites (dependent upon another organism for life).
See the entire definition of Bacteria

Bacterial: Of or pertaining to bacteria. For example, a bacterial lung infection.

Biopsy: The removal of a sample of tissue for purposes of diagnosis. (Many definitions of "biopsy" stipulate that the sample of tissue is removed for examination under a microscope. This may or may not be the case. The diagnosis may be achieved by other means such as by analysis of chromosomes or genes.)
See the entire definition of Biopsy

Blood count: The calculated number of white or red blood cells (WBCs or RBCs) in a cubic millimeter of blood.

Bumps: The raised area of a bump or bruise results from blood leaking from these injured blood vessels into the tissues as well as from the body's response to the injury. A purplish, flat bruise that occurs when blood leaks out into the top layers of skin is referred to as an ecchymosis.

Cancer: An abnormal growth of cells which tend to proliferate in an uncontrolled way and, in some cases, to metastasize (spread).
See the entire definition of Cancer

CBC: A commonly used abbreviation in medicine that stands for complete blood count, a set values of the cellular (formed elements) of blood. These measurements are generally determined by specially designed machines that analyze the different components of blood in less than a minute.
See the entire definition of CBC

Cellulitis: An acute spreading bacterial infection below the surface of the skin characterized by redness (erythema), warmth, swelling, and pain. Cellulitis can also cause fever, chills, and "swollen glands" (enlarged lymph nodes). Cellulitis is a clinical diagnosis based on the spreading involvement of skin and subcutaneous tissues with erythema, swelling, and local tenderness, accompanied by fever and malaise.
See the entire definition of Cellulitis

Chemotherapy: 1. In the original sense, a chemical that binds to and specifically kills microbes or tumor cells. The term chemotherapy was coined in this regard by Paul Ehrlich (1854-1915).
2. In oncology, drug therapy for cancer. Also called "chemo" for short.
See the entire definition of Chemotherapy

Chickenpox: A highly infectious viral disease also known medically as varicella -- in many countries, this disease is always called "varicella" -- that causes a blister-like rash, itching, fatigue and fever. The rash crops up first on the face and trunk and can spread over the entire body resulting in 250 to 500 itchy blisters.


See the entire definition of Chickenpox

Chills: feelings of coldness accompanied by shivering. Chills may develop after exposure to a cold environment or may accompany a fever.

Chronic: This important term in medicine comes from the Greek chronos, time and means lasting a long time.
See the entire definition of Chronic

Complete blood count: A set values of the cellular (formed elements) of blood. These measurements are generally determined by specially designed machines that analyze the different components of blood in less than a minute.
See the entire definition of Complete blood count

Contact dermatitis: A skin condition caused by contact between skin and some substance. Includes irritant contact dermatitis (a rash brought on purely by repeated irritation from a substance such as water causing "dish pan hands") and allergic contact dermatitis (involving a specific sensitivity or allergy to a specific substance such as poison ivy).

Cortisone: An adrenocorticoid hormone, a naturally occurring hormone made by and secreted by the adrenal cortex, the outer part (the cortex) of the adrenal gland.
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Coxsackievirus: A family of enteroviruses first found in the town Coxsackie south of Albany, New York. The Coxsackieviruses are separable into two groups: A and B. Type A viruses cause herpangina (sores in the throat) and hand, foot and mouth disease. Type B viruses cause epidemic pleurodynia. Both types A and B viruses can cause meningitis, myocarditis and pericarditis, and acute onset juvenile diabetes. Sometimes written Coxsackievirus. See also: Enterovirus.

Cryptococcosis: Infection with fungus (usually in a yeast form) from the genus Cryptococcus, such as Cryptococcus neoformans or Cryptococcus gattii. Cryptococcosis is generally a rare condition, but about 7%-15% of people with AIDS may acquire the infection. Infection is rare but can also occur in people with a normally functioning immune system. The infection can manifest as pneumonia with spread to the brain and other organs. Cryptococcal meningoencephalitis is fatal if not treated. Amphotericin B and other antifungal medications are used to treat cryptococcosis.

Curable: Amenable to a cure, capable of being cured, to being healed and made well. Most skin cancers, fortunately, are curable. From the word cure, from the Latin cura meaning care, concern or attention.

Dermatitis: Inflammation of the skin, either due to direct contact with an irritating substance, or to an allergic reaction. Symptoms of dermatitis include redness, itching, and in some cases blistering.
See the entire definition of Dermatitis

Dermatologist: A doctor who specializes in the diagnosis and treatment of skin problems.

Diagnosis: 1 The nature of a disease; the identification of an illness. 2 A conclusion or decision reached by diagnosis. The diagnosis is rabies. 3 The identification of any problem. The diagnosis was a plugged IV.
See the entire definition of Diagnosis

Doxycycline: Brand name: Vibramycin. A synthetic broad-spectrum antibiotic derived from tetracycline. Doxycycline is used for many different types of infections, including respiratory tract infections due to Hemophilus influenzae, Streptococcus pneumoniae, or Mycoplasma pneumoniae. It is also used for the treatment of nongonococcal urethritis (due to Ureaplasma), Rocky Mountain spotted fever, typhus, chancroid, cholera, brucellosis, syphilis, and acne.
See the entire definition of Doxycycline

Dry skin: Abnormally dry skin. Can be caused by a dry climate, winter weather, deficiency of vitamin A, systemic illness, overexposure to sunlight, or medication. The skin loses moisture. It may crack and peel. Or it may become irritated, inflamed, and itch. Bathing frequently, especially with soaps, can contribute to dry skin.
See the entire definition of Dry skin

EBV: Epstein-Barr virus, best known as the cause of infectious mononucleosis ("mono").
See the entire definition of EBV

Eczema: A particular type of inflammatory reaction of the skin in which there are typically vesicles (tiny blister-like raised areas) in the first stage followed by erythema (reddening), edema (swelling), papules (bumps), and crusting of the skin followed, finally, by lichenification (thickening) and scaling of the skin. Eczema characteristically causes itching and burning of the skin.
See the entire definition of Eczema

Epstein-Barr virus: A virus, abbreviated EBV, best known as the cause of infectious mononucleosis ("mono").
See the entire definition of Epstein-Barr virus

Erythromycin: Erythromycin is a common antibiotic for treating bacterial infection. Sold under many brand names, including EES, Erycin and Erythromia.

Fasciitis: Inflammation of the fascia (a lining tissue under the skin that covers a surface of underlying tissues).

Fetus: The unborn offspring from the end of the 8th week after conception (when the major structures have formed) until birth. Up until the eighth week, the developing offspring is called an embryo.

Fever: Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered to have a significant fever until the temperature is above 100.4 degrees F (38 degrees C.).
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Folliculitis: An infection of the hair follicles of the skin. Infection of the hair follicles can occur when the skin is disrupted or inflamed due to a number of conditions, including acne, skin wounds or injuries, friction from clothing, excessive sweating, or exposure to toxins. The symptoms vary and include small, red bumps or blisters around hair follicles, blisters filled with pus, or itching and tenderness of the involved area. When the deeper parts of the hair follicle are infected, a painful lump or mass may be felt.
See the entire definition of Folliculitis

Fungal: Pertaining to a fungus. For example, a fungal skin infection.

Fungi: Plural of fungus.

Fungus: A single-celled or multicellular organism. Fungi can be true pathogens (such as histoplasmosis and coccidioidomycosis) that cause infections in healthy persons or they can be opportunistic pathogens (such as aspergillosis, candidiasis, and cryptococcosis) that cause infections in immunocompromised persons (including cancer patients, transplant recipients, and persons with AIDS). An example of a common fungus is the yeast organism which causes thrush and diaper rash (diaper dermatitis). Fungi are also used for the development of antibiotics, antitoxins, and other drugs used to control various human diseases.

Gram stain: The Danish bacteriologist J.M.C. Gram (1853-1938) devised a method of staining bacteria using a dye called crystal (gentian) violet. Gram's method helps distinguish between different types of bacteria.
See the entire definition of Gram stain

Groin: In anatomy, the area where the upper thigh meets the trunk. More precisely, the fold or depression marking the juncture of the lower abdomen and the inner part of the thigh.
See the entire definition of Groin

Guttate psoriasis: A type of psoriasis characterized by red, scaly patches of inflamed skin on all parts of the body. It is associated with a lung infection in many cases.

Headache: A pain in the head with the pain being above the eyes or the ears, behind the head (occipital), or in the back of the upper neck. Headache, like chest pain or back ache, has many causes.
See the entire definition of Headache

Herpes: A family of viruses. Herpes also refers to infection with one of the human herpesviruses, especially herpes simplex types 1 and 2.
See the entire definition of Herpes

Herpes zoster: Also called shingles, zona, and zoster. The culprit is the varicella-zoster virus. Primary infection with this virus causes chickenpox (varicella). At this time the virus infects nerves (namely, the dorsal root ganglia) where it remains latent (lies low) for years. It can then be reactivated to cause shingles with blisters over the distribution of the affected nerve accompanied by often intense pain and itching.

Histoplasmosis: A disease caused by the fungus Histoplasma capsulatum. Most people with histoplasmosis have no symptoms. However, histoplasma can cause acute or chronic lung disease and progressive disseminated histoplasmosis affecting a number of organs. It can be fatal if untreated.
See the entire definition of Histoplasmosis

HIV: Acronym for the Human Immunodeficiency Virus, the cause of AIDS (acquired immunodeficiency syndrome). HIV has also been called the human lymphotropic virus type III, the lymphadenopathy-associated virus and the lymphadenopathy virus. No matter what name is applied, it is a retrovirus. (A retrovirus has an RNA genome and a reverse transcriptase enzyme. Using the reverse transcriptase, the virus uses its RNA as a template for making complementary DNA which can integrate into the DNA of the host organism).
See the entire definition of HIV

Hives: A raised, itchy area of skin that is usually a sign of an allergic reaction. It can be rounded or flat-topped but is always elevated above the surrounding skin. It reflects circumscribed dermal edema (local swelling of the skin). The hives are usually well circumscribed but may be coalescent and will blanch with pressure. They typically last less than 4 hours but they may stay for days or weeks. Approximately 20% of the population has experienced a bout of hives.
See the entire definition of Hives

Hygiene: The science of preventive medicine and the preservation of health. From the name of Hygeia, the daughter of Asklepios, the Greek god of medicine (whose staff with entwined snake is the symbol of medicine). Asklepios (known to the Romans as Aesculapius) had a number of children including not only Hygeia but also Panaceia, the patroness of clinical medicine. Hygeia also followed her father into medicine. As the patroness of health, Hygeia was charged with providing a healthy environment to prevent illness. In Greek, "hygieia" means health.

Immune: Protected against infection. The Latin immunis means free, exempt.

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Immune system: A complex system that is responsible for distinguishing us from everything foreign to us, and for protecting us against infections and foreign substances. The immune system works to seek and kill invaders.
See the entire definition of Immune system

Impetigo: A bacterial skin infection caused by the staphylococcus or, more rarely,streptococcus bacteria. The first sign of impetigo is a patch of red, itchy skin. Pustules develop on this area, soon forming crusty, yellow-brown sores that can spread to cover entire areas of the face, arms, and other body parts. Most patients are children. Treatment is by antibiotics.

Infection: The growth of a parasitic organism within the body. (A parasitic organism is one that lives on or in another organism and draws its nourishment therefrom.) A person with an infection has another organism (a "germ") growing within him, drawing its nourishment from the person.
See the entire definition of Infection

Inflammation: A basic way in which the body reacts to infection, irritation or other injury, the key feature being redness, warmth, swelling and pain. Inflammation is now recognized as a type of nonspecific immune response.
See the entire definition of Inflammation

Injury: Harm or hurt. The term "injury" may be applied in medicine to damage inflicted upon oneself as in a hamstring injury or by an external agent on as in a cold injury. The injury may be accidental or deliberate, as with a needlestick injury. The term "injury" may be synonymous (depending on the context) with a wound or with trauma.

Itching: An uncomfortable sensation in the skin that feels as if something is crawling on the skin or in the skin, and makes the person want to scratch the affected area.
See the entire definition of Itching

Laboratory: A place for doing tests and research procedures and preparing chemicals, etc. Although "laboratory" looks very like the Latin "laboratorium" (a place to labor, a work place), the word "laboratory" came from the Latin "elaborare" (to work out, as a problem, and with great pains), as evidenced by the Old English spelling "elaboratory" designating "a place where learned effort was applied to the solution of scientific problems."

Lesion: Pronounced "lee-sion" with the emphasis on the "lee," a lesion can be almost any abnormality involving any tissue or organ due to any disease or any injury.
See the entire definition of Lesion

Lips: Aside from the lips of the mouth, there are two pairs of lips at the entrance to the vagina. They are the labia majora (the larger outside pair) and the labia minora (the smaller inside pair). Together they form part of the vulva (the female external genitalia).

Liver: An organ in the upper abdomen that aids in digestion and removes waste products and worn-out cells from the blood. The liver is the largest solid organ in the body. The liver weighs about three and a half pounds (1.6 kilograms). It measures about 8 inches (20 cm) horizontally (across) and 6.5 inches (17 cm) vertically (down) and is 4.5 inches (12 cm) thick.


See the entire definition of Liver

Lupus: A chronic inflammatory condition caused by an autoimmune disease. An autoimmune disease occurs when the body's tissues are attacked by its own immune system. Patients with lupus have unusual antibodies in their blood that are targeted against their own body tissues.
See the entire definition of Lupus

Macular: Pertaining to the macula. A macula is a small spot. A macula on the skin is a small flat spot while the macula in the eye is a small spot where vision is keenest in the retina.


See the entire definition of Macular

Microscope: An optical instrument that augments the power of the eye to see small objects. The name microscope was coined by Johannes Faber (1574-1629) who in 1628 borrowed from the Greek to combined micro-, small with skopein, to view. Although the first microscopes were simple microscopes, most (if not all) optical microscopes today are compound microscopes.

Microscopic: So small it cannot be seen without the aid of microscope. As opposed to macroscopic (large enough to be seen with naked eye). A tiny tumor is microscopic while a big tumor is macroscopic.

Microscopy: The examination of minute objects by means of a microscope, an instrument which provides an enlarged image of an object not visible with the naked eye.
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Mite: A tiny eight-legged creature belonging to the Order Acarina related to spiders and ticks. Some mites live freely and others as parasites. Mites can attack plants and animals, carry disease, and cause allergies. acaricide.

Mononucleosis: Infection with the Epstein-Barr virus (EBV, human herpesvirus 4, HHV-4) in which there is an increase of white blood cells that have a single nucleus (monocytes). The infection can be spread by saliva. Its incubation period is four to eight weeks. Symptoms include fever, fatigue, sore throat, and swollen lymph glands. Mononucleosis can cause liver inflammation (hepatitis) and spleen enlargement; vigorous contact sports should be avoided to prevent spleen rupture. It is less severe in young children.
See the entire definition of Mononucleosis

Mouth: 1. The upper opening of the digestive tract, beginning with the lips and containing the teeth, gums, and tongue. Foodstuffs are broken down mechanically in the mouth by chewing and saliva is added as a lubricant. Saliva contains amylase, an enzyme that digests starch. 2. Any opening or aperture in the body. The mouth in both senses of the word is also called the os, the Latin word for an opening, or mouth. The o in os is pronounced as in hope. The genitive form of os is oris from which comes the word oral.

MRSA infection: Frequently used abbreviation for: Methicillin-resistant staphylococcus aureus.
See the entire definition of MRSA infection

Nail: In medicine, there are two types of nails. One is just a plain old metal nail used to hold 2 or more pieces of bone together, for example, after a fracture. The other type of nail is the horny plate on the end of the finger or toe. Each nail anatomically has a body, lateral nail folds (on the sides), a lunula (the little moon-shaped feature at the base), and a proximal skin fold (at the base).

Nasal: Having to do with the nose. Nasal drops are intended for the nose, not (for example) the eyes. The word "nasal" came from the Latin "nasus" meaning the nose or snout.

Neck: The part of the body joining the head to the shoulders. Also, any narrow or constricted part of a bone or organ that joins its parts as, for example, the neck of the femur bone.

Necrotizing fasciitis: A dangerous infection of soft-tissue that starts in the subcutaneous tissue (just below the skin) and spreads along the flat layers of fibrous tissue that separate different layers of tissue (fascial planes). It most commonly occurs in the arms, legs and abdominal wall. The death rate is up to 40%.
See the entire definition of Necrotizing fasciitis

Nickel: A silver-white metallic element. Long-term exposure to nickel, such as from jewelry, can cause a form of contact dermatitis called nickel dermatitis. Exposure to nickel fumes can cause nasal cancer and lung cancer.

Nose: The external midline projection from the face.
See the entire definition of Nose

Ointment: A medication preparation that is applied topically (onto the skin). An ointment has an oil base whereas a cream is water-soluble. (The word ointment comes from the Latin ungere meaning anoint with oil).

Onset: In medicine, the first appearance of the signs or symptoms of an illness as, for example, the onset of rheumatoid arthritis. There is always an onset to a disease but never to the return to good health. The default setting is good health.
See the entire definition of Onset

Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pain has both physical and emotional components. The physical part of pain results from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it can be more diffuse, as in disorders like fibromyalgia. Pain is mediated by specific nerve fibers that carry the pain impulses to the brain where their conscious appreciation may be modified by many factors.
See the entire definition of Pain

Papular: Adjective referring to one or more small solid rounded bumps rising from the skin that are each usually 0.5 cm or less in diameter (less than a half inch across).
See the entire definition of Papular

Parasitic: Having to do with a parasite, as in a parasitic infection; or acting like a parasite by taking nourishment from another.

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Penicillin: The most famous of all antibiotics, named for the fungal mold Penicillium notatum from which it is derived. Penicillin acts by destroying the cell wall of bacteria.
See the entire definition of Penicillin

Poison: Any substance that can cause severe distress or death if ingested, breathed in, or absorbed through the skin. Many substances that normally cause no problems, including water and most vitamins, can be poisonous if taken in too large of a quantity. Poison treatment depends on the substance: if there are treatment instructions on the substance's container and you are sure it contained no other item, follow those directions immediately. Always contact your nearest Poison Control Center if you are concerned about possible poison ingestion.

Poison ivy: Skin inflammation resulting from contact with oils from the poison ivy vine. Chemicals produced by this vine cause an immune reaction, producing redness, itching, and blistering of the skin.
See the entire definition of Poison ivy

Poison oak: Poison oak is a form of "contact dermatitis" or inflammation of the skin resulting from chemicals produced from the poison oak plant contacting the skin. The chemicals cause an immune reaction producing redness, itching and blistering of the skin.

Potassium: The major positive ion (cation) found inside of cells. The chemical notation for potassium is K+.
See the entire definition of Potassium

Pregnancy: The state of carrying a developing embryo or fetus within the female body. This condition can be indicated by positive results on an over-the-counter urine test, and confirmed through a blood test, ultrasound, detection of fetal heartbeat, or an X-ray. Pregnancy lasts for about nine months, measured from the date of the woman's last menstrual period (LMP). It is conventionally divided into three trimesters, each roughly three months long.
See the entire definition of Pregnancy

Psoriasis: A reddish, scaly rash often located over the surfaces of the elbows, knees, scalp, and around or in the ears, navel, genitals or buttocks. Psoriasis is an autoimmune disease that is mediated by T lymphocytes. It is also a very common disease, Chronic plaque psoriasis affects approximately 2% of people around the world. About 10-15% of patients with psoriasis develop joint inflammation (inflammatory arthritis). Treatment options include topical steroid creams, tar soap preparations, and exposure to ultraviolet light.
See the entire definition of Psoriasis

Pus: A thick whitish-yellow fluid which results from the accumulation of white blood cells (WBCs), liquified tissue and cellular debris. Pus is commonly a site of infection or foreign material in the body.

Rash: Breaking out (eruption) of the skin. Medically, a rash is referred to as an exanthem.

Recurrent: Back again. A recurrent fever is a fever that has returned after an intermission: a recrudescent fever.

Refractory: Not yielding (at least not yielding readily) to treatment.

Respiratory: Having to do with respiration, the exchange of oxygen and carbon dioxide. From the Latin re- (again) + spirare (to breathe) = to breathe again.

Rosacea: A chronic skin disease that affects the middle third of the face with persistent redness over the areas of the face and nose that normally blush: mainly the forehead, the chin and the lower half of the nose. The tiny blood vessels in these areas enlarge (dilate) and become more visible through the skin, appearing like tiny red lines (called telangiectasias). Pimples can occur that look like teenage acne.
See the entire definition of Rosacea

Rule out: A term much used in medicine, meaning to eliminate or exclude something from consideration. The ACB (albumin cobalt binding) test helps rule out a heart attack in the differential diagnosis of severe chest pain.

Saliva: a watery secretion in the mouth produced by the salivary glands that aids in the digestion of food. Saliva also serves to moisten and cleanse the mouth, including the tongue and teeth, and contains substances that can play a role in the prevention of infection. Saliva aids digestion by moistening food and contains enzymes that begin the digestion process. Also known as spit.

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Sarcoidosis: A disease of unknown origin that causes small lumps (granulomas) due to chronic inflammation to develop in a great range of body tissues. Sarcoidosis can appear in almost any body organ, but most often starts in the lungs or lymph nodes. It also affects the eyes, liver and skin; and less often the spleen, bones, joints, skeletal muscles, heart and central nervous system (brain and spinal cord).
See the entire definition of Sarcoidosis

Scabies: Infestation of the skin by the human itch mite, Sarcaptes scabies. The initial symptom of scabies are red, raised bumps that are intensely itchy. A magnifying glass will reveal short, wavy lines of red skin, which are the burrows made by the mites. Treatment is with any of several scabicide medications.
See the entire definition of Scabies

Scalded skin syndrome: A potentially serious side effect of infection with the Staph (Staphylococcus) bacteria that produces a specific protein which loosens the "cement" holding the various layers of the skin together. This allows blister formation and sloughing of the top layer of skin. If it occurs over large body regions it can be deadly (just like a large surface area of the body having been burned). It is necessary to treat scalded skin syndrome with intravenous antibiotics and to protect the skin from allowing dehydration to occur if large areas peel off. The disease occurs predominantly in children under 5 years of age. It is known formally as Staphylococcal scalded skin syndrome and as Ritter disease.

Scaling: Abnormal shedding or accumulation of an upper layer of skin (the stratum corneum).

Scarlet fever: Also called scarlatina, a disease caused by infection with group A streptococcal bacteria that occurs in a small proportion of people with strep throat.
See the entire definition of Scarlet fever

Scleroderma: A disease of connective tissue with the formation of scar tissue (fibrosis) in the skin and sometimes also in other organs of the body.
See the entire definition of Scleroderma

Seborrhea: A chronic inflammatory disease of the skin characterized by the accumulation of scales of greasy skin. There may be yellow crusted patches that are itchy. Seborrhea often affects the scalp. Other sites include the face, ears, eyebrows and eyelids, umbilicus, and genitalia, Seborrhea of the scalp is commonly known as dandruff.
See the entire definition of Seborrhea

Seborrheic dermatitis: A medical name for what is popularly called seborrhea.

Sensitivity: 1. In psychology, the quality of being sensitive. As, for example, sensitivity training, training in small groups to develop a sensitive awareness and understanding of oneself and of ones relationships with others. 2. In disease epidemiology, the ability of a system to detect epidemics and other changes in disease occurrence. 3. In screening for a disease, the proportion of persons with the disease who are correctly identified by a screening test. 4. In the definition of a disease, the proportion of persons with the disease who are correctly identified by defined criteria.

Shingles: An acute infection caused by the herpes zoster virus, the same virus as causes chickenpox. Shingles is most common after the age of 50 and the risk rises with advancing age. Shingles occurs because of exposure to chickenpox or reactivation of the herpes zoster virus. The virus remains latent (dormant) in nerve roots for many years following chickenpox.
See the entire definition of Shingles

Skin biopsy: Removal of a piece of skin for the purpose of further examination in the laboratory using a microscope.


See the entire definition of Skin biopsy

Staphylococcal scalded skin syndrome: An infection of the skin with group II Staphylococcus aureus bacteria. The bacteria release toxins, causing inflamed, scaling skin that looks as though it has been burned. It is more common in children than in adults, but is more likely to cause death when it does occur in adults. Rehydration and intravenous antibiotics are the most common treatments. Steroids will worsen the condition, and should not be used. Abbreviated SSSS.

Staphylococcus: A group of bacteria that cause a multitude of diseases. Under a microscope, Staphylococcus bacteria are round and bunched together. They can cause illness directly by infection, or indirectly through products they make, such as the toxins responsible for food poisoning and toxic shock syndrome. The best known member of the Staphylococcus family is Staphylococcus aureus. Staphylococcus are the main culprit in hospital-acquired infections, and cause thousands of deaths every year.

Steroid: A general class of chemical substances that are structurally related to one another and share the same chemical skeleton (a tetracyclic cyclopenta[a]phenanthrene skeleton).
See the entire definition of Steroid

Strep: Very commonly used shortened form of Streptococcus, a very common and important group of bacteria. See Streptococcus

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Strep throat: Strep throat is an infection caused by a type of bacteria called streptococcus, which can lead to serious complications if not adequately treated.

Streptococcus: A group of bacteria, familiarly known as strep, that cause a multitude of diseases. The name comes from the Greek strepto- meaning twisted + kokkos meaning berry, and that is exactly what strep look like under the microscope, like a twisted bunch of little round berries. Illness caused by strep includes strep throat, strep pneumonia, scarlet fever, rheumatic fever (and rheumatic heart valve damage), glomerulonephritis, the skin disorder erysipelas, and PANDAS.

Superficial: In anatomy, on the surface or shallow. As opposed to deep. The skin is superficial to the muscles. The cornea is on the superficial surface of the eye.
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Syndrome: A set of signs and symptoms that tend to occur together and which reflect the presence of a particular disease or an increased chance of developing a particular disease.
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Systemic: Affecting the entire body. A systemic disease such as diabetes can affect the whole body. Systemic chemotherapy employs drugs that travel through the bloodstream and reach and affect cells all over the body.

Systemic lupus erythematosus: A chronic inflammatory condition caused by an autoimmune disease. An autoimmune disease occurs when the body's tissues are attacked by its own immune system. Patients with lupus have unusual antibodies in their blood that are targeted against their own body tissues.
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Therapy: The treatment of disease.
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Throat: The throat is the anterior (front) portion of the neck beginning at the back of the mouth, consisting anatomically of the pharynx and larynx. The throat contains the trachea and a portion of the esophagus.

Thyroid: 1. The thyroid gland. Also, pertaining to the thyroid gland. 2. A preparation of the thyroid gland used to treat hypothyroidism. 3. Shaped like a shield. (The thyroid gland was so-named by Thomas Wharton in 1656 because it was shaped like an ancient Greek shield.)
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Thyroiditis: Inflammation of the thyroid gland which is located in front of the neck:


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Topical: Pertaining to a particular surface area. A topical agent is applied to a certain area of the skin and is intended to affect only the area to which it is applied. Whether its effects are indeed limited to that area depends upon whether the agent stays where it is put or is absorbed into the blood stream.

Tzanck smear: See Tzanck test.

Urticaria: Another name for the hives. Raised, itchy areas of skin that are usually a sign of an allergic reaction. Hives can be rounded or flat-topped but are always elevated above the surrounding skin. They reflect circumscribed dermal edema (local swelling of the skin). The hives are usually well circumscribed but may be coalescent and will blanch with pressure.
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Vaccination: Injection of a killed microbe in order to stimulate the immune system against the microbe, thereby preventing disease. Vaccinations, or immunizations, work by stimulating the immune system, the natural disease-fighting system of the body. The healthy immune system is able to recognize invading bacteria and viruses and produce substances (antibodies) to destroy or disable them. Immunizations prepare the immune system to ward off a disease. To immunize against viral diseases, the virus used in the vaccine has been weakened or killed. To only immunize against bacterial diseases, it is generally possible to use a small portion of the dead bacteria to stimulate the formation of antibodies against the whole bacteria. In addition to the initial immunization process, it has been found that the effectiveness of immunizations can be improved by periodic repeat injections or "boosters." Also see Vaccines (in the plural) and Vaccine of a specific type (such Vaccine, Polio).

Vesicular: Pertaining to the presence of one or more vesicles. A vesicle is a small blister.
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Viral: Of or pertaining to a virus. For example, "My daughter has a viral rash."

Viral infection: Infection caused by the presence of a virus in the body. Depending on the virus and the person's state of health, various viruses can infect almost any type of body tissue, from the brain to the skin. Viral infections cannot be treated with antibiotics; in fact, in some cases the use of antibiotics makes the infection worse. The vast majority of human viral infections can be effectively fought by the body's own immune system, with a little help in the form of proper diet, hydration, and rest. As for the rest, treatment depends on the type and location of the virus, and may include anti-viral or other drugs.

Virus: A microorganism smaller than a bacteria, which cannot grow or reproduce apart from a living cell. A virus invades living cells and uses their chemical machinery to keep itself alive and to replicate itself. It may reproduce with fidelity or with errors (mutations)-this ability to mutate is responsible for the ability of some viruses to change slightly in each infected person, making treatment more difficult.
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Viruses: Small living particles that can infect cells and change how the cells function. Infection with a virus can cause a person to develop symptoms. The disease and symptoms that are caused depend on the type of virus and the type of cells that are infected.

Xerosis: Abnormal dryness of the skin (xeroderma), of the conjunctiva of the eye (xerophthalmia), or of the mucous membranes such as dry mouth (xerostomia).
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Yeast infection: Overgrowth of yeast can affect the skin (yeast rash), mouth (thrush), digestive tract, esophagus, vagina (vaginitis), and other parts of the body. Yeast infections occur most frequently in moist areas of the body. Although Candida albicans and other Candida yeasts are the most frequent offenders, other yeast groups are known to cause illness, primarily in immunocompromised patients. These include Torulopsis, Cryptococcus, Malassezia, and Trichosporon yeasts. Diagnosis is by observation, and can be confirmed by culturing a stool or mucosa sample, or a scraping from the affected area. Treatment is by topical or oral antifungal medications. Acidophilous, a helpful bacteria that normally helps to keep yeast in check, can also be tried in supplement form or in yogurt with live cultures.
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Rosacea Overview

Rosacea (commonly referred to as adult acne) is a chronic inflammatory condition affecting the central face of adults (it is rare in children) and manifested by redness of the forehead, eyelids, cheeks, nose, and chin. Rosacea is often accompanied by inflammatory papules (raised bumps) and pustules (bumps containing pus), or rarely with enlargement of the connective tissues beneath the skin (termed phymatous rosacea), including the nasal tissues (known as rhinophyma).

Rosacea Causes

Ultimately, the cause of rosacea is unknown, but it is generally agreed that affected people have an unusual degree of vascular hyper-reactivity in that they tend to manifest vigorous and prolonged facial flushing in response to the ingestion of hot liquids. After a time, the flushing becomes permanent due to persistent enlargement of small facial blood vessels (telangiectasia).

It seems likely that genes also play ...

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