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HIV Glossary: Definitions of Common Words and Terms

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Abstinence: refers to refraining completely from something; in reference to HIV infection and AIDS, it usually refers to completely avoiding sexual intercourse to avoid passing an HIV infection from one partner to another

Anemia: low red blood cells; when red blood cells are too low the person is short of breath, pale, and experiences a fast heart beat

AIDS: acquired immunodeficiency syndrome; this is the result of HIV infection that has seriously injured the immune system and makes the patient subject to fever, chills, nightsweats, weight loss, and unusual infections (see "opportunistic infections" below)

Addiction: a problem that is defined by a repeated action that does harm to the person doing it but the person continues to do the activity and usually increases the activity; it can apply to drugs (for example, alcohol, nicotine in cigarettes, pain pills, heroin, cocaine) or to activities (for example, sex, vomiting, eating, and even exercise in extreme cases)

Adherence: following a plan or treatment program consistently

Antiretroviral: any drug or treatment which inhibits or kills a retrovirus like HIV

Antiviral: any drug or treatment which inhibits or kills a virus

Antibiotic: any drug or treatment which inhibits or kills a microbe or germ; usually this refers to treatments for bacteria (for example, staph or strept)

Antimicrobial: this is another name for an antibiotic


BID: this is a medical abbreviation for "take twice a day" which translates to "take twice a day and as close to 12 hours apart as possible"


Cardiovascular: refers to the heart and blood vessels

CD4-lymphocyte:  this is the immune cell which is killed by HIV; the number of these cells per unit of blood ("CD4 count") determines how low one's immune system is or how hard one can fight or resist certain infections; this test is not directly affected by treatment (see "Viral load")

Cervicitis: refers to an inflammatory condition of the cervix which usually results from a sexually transmitted disease (for example, gonorrhea, chlamydia, herpes)

Cervix: the cuff of tissue that leads into the uterus

Clitoris: this is the female sex organ, located in the vagina

Condom: a device which prevents secretion from one person from touching another person; usually a pouch-like rubber which is fitted over the male penis or into the female vagina; also know as a "rubber"

Complete blood count (CBC): a blood test done to count white cells, red cells, and platelet cells as well as provide information on size of the cells

Compliance: the preferred term is "Adherence", see above

Cryptococcosis: an infection due to a fungus called Cryptococcus neoformans that causes meningitis, pneumonia and other problems

Cryptosporidiosis: refers to a parasitic infection that causes minor diarrhea in persons with normal immune systems, but in the setting of AIDS, cryptosporidiosis can cause severe, chronic watery diarrhea that can kill

CT: refers to "computerized tomography" which is a procedure to use x-rays to make a 3-dimensional picture of the body for diagnosis

Cunnilingus: this refers to oral stimulation / sex from one partner on the other partner's (female sex organ) clitoris

Cytomegalovirus (CMV): refers to a virus that very commonly causes minor infections in persons with normal immune systems or less often but more severe infections of the eye, lungs, liver, or brain in persons with AIDS


Dermatitis: refers to an inflammatory condition of the skin or sometimes to any abnormality of the skin

Diagnosis: this is the conclusion that a healthcare provider comes to after they review all the available information and tests related to medical problems

Diarrhea: loose, liquid and/or frequent stools; diarrhea can be caused by infections (for example food poisoning, antibiotics), drugs (like nelfinavir), poor absorption (for example, too much cream in the diet) or surgery (removal of the colon)

DMAC: refers to disseminated MAC (see below); this means that the MAC has spread through the bloodstream to many areas of the body, usually the bone marrow, liver, lymph nodes


ELISA: Enzyme Linked Immuosorbent Assay; this is a screening test that is done for HIV infection as well as for other types of things; in the case of HIV, the ELISA must be confirmed by further testing (see "Western Blot") before the diagnosis of HIV is made

Encephalitis: refers to any inflammation within the brain but encephalitis is usually due to infections like syphilis, viruses (for example West Nile Virus, St Louis encephalitis, herpes), fungus, bacteria or TB

Epididymis: this is a structure within the male scrotum that produces some of the fluid that contributes to the male ejaculation fluid ("cum")

Epididymitis: an inflammatory and usually infectious condition of the epididymis which results in pain, tenderness, and swelling with the male scrotum; usually epididymitis is due to either a sexually transmitted disease (for example, gonorrhea, chlamydia) in younger men or to germs that cause urinary tract infections (E coli) in older men

Epstein Barr virus (EBV): the virus that causes mononucleosis (see below) or "Kissing Fever"

Erectile dysfunction (ED): refers to problems when the male cannot get or maintain an erection during sexual intercourse; there are many causes including hormones, psychological issues, medications, and nervous system problems

Esophagitis: inflammatory condition of the tube (esophagus) that goes from the throat to the stomach, usually due to excess acid (esophageal reflux or GERD) or infection (for example, yeast, herpes, CMV); characterized by usually burning chest pain and pain or difficulty swallowing


Fellatio: this refers to oral stimulation / sex from one partner to the other partner's penis

Fusion inhibitor: refers to a drug that inhibits the binding of HIV to a T-cell (for example, enfuvirtide)


Genital organ: this refers to the male or female reproductive or sex organ

Genotype: a blood test to determine what specific resistance a person's strain of HIV has so that medication can be changed for best results

Gingivitis: refers to an inflammatory condition of the gums in the mouth that can result in bad breath, tooth decay, and pain; it usually results from not taking care of the mouth and teeth with brushing, flossing, and dental visits; there is an increased risk for gingivitis due to HIV infection


Harm reduction: refers to reducing the health impact of unhealthy behaviors such as smoking, alcohol use, nonprescribed drug use, or nonadherence to medications or healthcare visits

Hemophiliac: a person who lacks factors in the blood that allow it to clot normally; these persons can bleed spontaneously or with minor trauma externally or internally (for example, into joints, into the brain)

Hepatitis: any condition that is characterized by inflammation of the liver (for example, viral hepatitis, drug hepatitis, alcoholic hepatitis)

Herpes (simplex) virus (HSV): this is a virus which causes cold sores and similar sores on the genital organs or around the anus

Herpes zoster (also know as varicella zoster): this is the medical name for shingles which is a outbreak of varicella, the chicken pox virus, that occurs usually along a single nerve producing blisters and pain

Histoplasmosis: refers to a fungus infection that causes minor problems if one's immune system is intact, but in the setting of AIDS, it can cause life-threatening infections of the bloodstream, bone marrow, and lungs

HIV: human immunodeficiency virus, the virus that causes AIDs; it is also known as HIV-1 and it was formerly known as HTLV III

HTLV 1/2: refers to "human T-lymphotropic virus 1/2" which is a virus related to HIV that causes lymphoma (lymph gland cancer) and "tropical spastic paraparesis" in some people

Human papilloma virus (HPV): refers to the virus that causes warts on the body and in the genital areas


Immune system: this refers to the many functions of the human body which resist attack and infections from outside

Immunodeficiency: this refers to problems with the body's defenses against infections and cancer

IVDU: intravenous drug use or the use of usually illegal drugs injected directly into one's vein


Jaundice: an accumulation of yellow pigment that results in yellow eyes, yellow skin, and usually pale colored stools; this can be caused by hepatitis, breakup of red blood cells, or blocked bile ducts


Kaposi's sarcoma (KS): refers to a malignancy of the blood vessels, lymph nodes, and skin that occurs as result of immunodeficiency like AIDS and the presence of the KS virus (also known as human herpes virus 8, HHV-8); it usually starts on the skin but it may involve almost any organ in the body


Leukoplakia: refers to any whitish markings in the tissues of the mouth; leukoplakia may be due to viral infections or it might be an early sign of cancer

Lipids: the fat components of the blood (for example cholesterol, triglycerides, HDL, LDL) which are thought to contribute to risks for heart attacks, strokes, and arterial disease

Lipoatrophy: this refers to inappropriate loss of fat from certain areas of the body (for example, temples, cheeks, arms, legs) due to HIV and/or certain antiviral medications

Lipodystrophy: a term used to describe fat redistribution, high fat levels ("lipids") in the blood, and a tendency to cause diabetes that is associated with HIV and certain treatments for HIV

Liver enzymes: a blood test that is used to determine the state of the liver's health

Lumbar puncture: this is the medical name for "spinal tap", see below

Lymphocytes: these are the lymph cells which are produced by lymph glands to help fight infection


MAC: refers to a germ that is related to tuberculosis called Mycobacterium avium complex (formerly Mycobacterium avium intracellulare)

Meninges: refers to the delicate layers of tissue that surround the brain and spinal cord

Meningitis: refers to inflammation in the thin tissues ("meninges") that line the brain and/or spinal cord; usually due to infections with viruses, bacteria, fungi (for example, Cryptococcus neoformans,) or mycobacteria (for example, tuberculosis); meningitis is very serious and can be fatal; symptoms may include headache, fever, light sensitivity to the eyes, stiff neck, nausea, and sometime stroke-like problems

Meningoencephalitis: this refers to a combination of "meningitis" and "encephalitis", see above

MG or mg: refers to milligram which is a small unit of measure in the metric system which is equivalent to about 1/500 of a pound; this is the most common way that medication is measured

Mitochondria: refers to tiny structures within human cells which are responsible for the production of energy for the cell; mitchondria may be injured by certain drugs such as NRTIs

Mononucleosis: this is an acute disease caused by Epstein Barr virus that results in fever, headache, fatigue, and lymph node swelling; sometimes mononucleosis is mimiced by acute infection with HIV or CMV

MRI: this refers to "magnetic resonance imaging"; this is a procedure where powerful magnets are used to make a 3-dimensional picture of the body for diagnosis

Myocardial infarction (MI): refers to the medical terminology for a heart attack which is damage to the heart muscle as a result of loss of oxygen supply to that muscle; smoking, cholesterol levels, and family history are some of the risk factors for heart disease


Nonnucleoside reverse transcriptase inhibitor (NNRTI): this is a type of drug used against HIV infection that inhibits the production of HIV's genetic material (for example nevirapine, efavirenz, delavirdine)

Nucleoside reverse transcriptase inhibitor (NRTI): this is a type of drug used against HIV infection that also inhibits the production of HIV's genetic material (for example, zidovudine, didanosine, zalcitabine, stavudine)

Nucleotide reverse transcriptase inhibitor (NtRTI): this is a slight variation on a NRTI which has undergone an additional chemical reaction ("phosphorylation"); tenofovir is a NtRTI


Opportunistic infection (OI): this is an unusual infection that is only possible when one's immune system has been reduced by HIV or other causes (for example, leukemia, cancer chemotherapy); see the page on this site for more details (click HERE)

Oral hairy leukoplakia (OHL): refers to whitish markings usually along the sides of the tongue which are due to infection with the mononucleosis virus (Epstein Barr virus, EBV)


Pancreas: refers to an organ in the center of the upper belly which lies just beneath the second part of the stomach; this organ is responsible for secreting digestive juices as well as hormones into the bloodstream; insulin is one of the main hormones secreted by the pancreas' the pancreas can be injured by certain medications (for example, didanosine) as well as by alcohol

Pancreatitis: refers to an inflammatory condition of the pancreas that results from many causes (gall stones, drugs, alcohol); the symptoms of pancreatitis are abdominal pain, nausea, vomiting; pancreatitis can be fatal especially if it is acute

PPD: purified protein derivative; this is a small amount of material that is placed under the skin and 2-3 days later it is observed and measured for hardness; if it is hard and measures more than 10 mm (1 centimeter or a little less than 1/2 inch) than the person may have been exposed to tuberculosis (TB)

Pelvic inflammatory disease (PID): a complicated infection of the tubes which carry the female eggs to the uterus which produces lower abdominal pain; usually due to sexually transmitted diseases like chlamydia, gonorrhea, and other bacteria

Penis: the male sex organ

Peripheral neuropathy: this refers to the damage that either HIV itself, diabetes, prescribed drugs (for example zalcitabine, stavudine, isoniazid, dapsone,) alcohol and/or other conditions can do to nerves in the feet, legs and even the hands in very severe cases; usually begins as numbness or as if a rock is in one's shoe and gradually increases over days to weeks to months to severe burning pain, sometimes with shock-like or stabbing pain

Phenotype: a blood test to determine what specific resistance a person's strain of HIV has so that medication can be changed for best results

Pneumonia: an infection of the airspaces of the lung usually with fever, chills, cough, sputum, chest pain, high white blood cell count, and low oxygen in the blood

Pneumocystis pneumonia (PCP): a special type of possibly life-threatening pneumonia that occurs in AIDS when the immune system is low and the T-cells are usually less than 200

Prophylaxis: prevention; this may refer to prevention of sexual transmission or medications used to prevent certain infections

Prostate gland: one of the male sex glands; it contributes fluid to the male ejaculation; this gland may become enlarged and constrict the urethra and decrease the ability to empty the bladder

Protease inhibitor (PI): a drug that works against HIV (or other infections) by inhibiting the formation of proteins (for example, saquinavir, indinavir, amprenavir, lopinavir, ritonavir, nelfinavir, atazanavir)


QID: this is a medical abbreviation for "take four (4) times a day" which translates to "take four (4) times a day and as close to 6 hours apart as possible"


Red blood cells (RBC): these are cells in the blood that carry oxygen from the lungs to the tissues and then carry carbon dioxide from the tissues to the lungs

Resistance: in the case of HIV therapy this refers to properties of a particular strain of HIV that prevent HIV medication or medications from working; resistance results from nonadherence and/or low blood levels of HIV medications; it does not result usually from stopping HIV medications.  Once resistance develops it is usually permanent.

Retinitis: refers to an inflammatory state of the light-detecting tissues of the eye ("retina"); usually caused by viruses


Seborrhea: a common and usually minor skin condition that causes redness and scaling between the eyebrows and on the sides of the nose in the folds that lead to the mouth; it can be treated with creams but it will come back if treatment is stopped

Shingles: see Herpes zoster above

Spinal tap: this is the procedure where a healthcare provider places a small needle in the spine to remove fluid for important testing for syphilis, meningitis, or cancer; the procedure is relatively painless and very safe except in very rare instances

Sputum: the phlegm or material coughed up from the chest or bronchial tubes during a chest cold, bronchitis, pneumonia or tuberculosis


T-cells: this is short for T-helper lymphocytes or CD4-lymphocytes; these cells are the immune system cells that are killed by HIV

Testicles: the round soft male organs within the scrotum that produce sperm which is part of the male ejaculation fluid ("cum")

Thrush: yeast infection of the mouth and/or throat characterized by white cheesy deposits on the gums

Tinea: fungus infection of the scalp, body, nails, genital area

TID: this is a medical abbreviation for "take three times a day" which translates to "take three times a day and as close to 8 hours apart as possible"

Toxoplasmosis: a parasite found in cat stools or in undercooked red meat and on unwashed, unpeeled, or uncooked vegetables/frutis that can cause strokes and/or brain damage in someone with AIDS and low T-cells who is not taking a preventative medication

Tuberculosis (TB): an infection that is passed back and forth between humans by coughing that is more common in persons with HIV, persons who are alcoholics, persons who have been in jail, and persons born in certain areas of the world (for example, South America, Vietnam, Eastern Europe)

T-cell: this is another name for a CD4-lymphocyte (see above)

Transmission: refers to the act of passing an infection or a trait to someone else


Urethra: refers to the tube from the bladder where urine flows out of the body in both males and females; sexually transmitted diseases like gonorrhea or chlamydia may infect this tube

Urethritis: an inflammatory condition of the urethra (see above) usually caused by infections (for example, gonorrhea, chlamydia)

Uterus: the hollow organ within the female pelvis where fertilized eggs come to rest for development during pregnancy; the cervix leads to the uterus from the vagina and the Fallopian tubes lead from the ovaries to the uterus


Vagina: the female sex organ

Vaginitis: inflammatory condition of the vagina, usually due to infection (for example, yeast, bacterial vaginosis, gonorrhea, herpes), characterized by tenderness, discharge, abnormal odor

Venipuncture: the act of sticking a vein with a needle, usually for purposes of getting a blood sample for lab tests

Vertical transmission: this refers to mother-to-child infections that occur with HIV and certain other infections and genetic traits

Viral load: this is a blood test used to determine how much virus is in the blood either before or during treatment; this test tells how well a treatment is working against HIV


Western Blot: this is a confirmatory blood test for HIV infection that is done to make absolutely sure that a person has HIV

White blood cells (WBC): these cells are bloodstream cells that are important to the immune system; T-cells are part of the white blood cells





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