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Recommendations to Help Patients Avoid Exposure to or Infection from Opportunistic Pathogens*

Sexual Exposures

Male latex condoms, when used consistently and correctly during every act of sexual intercourse, are highly effective in preventing the sexual transmission of HIV and can reduce the risk for acquiring other sexually transmitted infections, including syphilis, chlamydia, gonorrhea, and trichomoniasis. Condom use might reduce the risk for transmission of herpes simplex virus and human papillomavirus (AII), although data are more limited. Data regarding the use and efficacy of female condoms are limited (BIII). Spermacides containing nonoxynol-9 (N-9) are not effective for HIV/STD prevention and should not be used as a microbicide or lubricant during vaginal or anal intercourse (EII).

As with many non-sexually transmitted opportunistic infections, intercurrent infections with sexually transmitted pathogens (especially pathogens that cause genital ulcers such as herpes simplex, syphilis, and chancroid) can stimulate increases in HIV viral load and consequent declines in CD4+ count. Furthermore, acquisition of STDs by HIV-infected patients indicates participation in high-risk sexual behavior capable of transmitting HIV to others, the risk for which is substantially increased in the presence of genital tract inflammation (e.g., from gonorrhea or chlamydia) and genital ulcer disease (e.g., HSV-2 infection, syphilis) (1-5). All patients, including patients who are asymptomatic, should be screened at least once for STDs. Screening should include testing for syphilis (AII), trichomoniasis in women (AII), urogenital gonorrhea and chlamydia (BII), and oral and rectal gonorrhea and chlamydia for patients reporting receptive sex at these anatomic sites (BII) (6,7). Nucleic acid amplification testing methods can be more sensitive and specific than traditional culture methods and might be more acceptable to patients. Detailed recommendations for STD testing in HIV-infected persons can be found at the following site: For all sexually active patients, STD screening should be repeated at least annually and whenever a patient reports high-risk sexual behaviors or symptoms (BIII). In addition to identifying and treating STDs, providers should screen HIV-infected patients for risk behaviors; communicate prevention messages; discuss sexual and drug-use behaviors; positively reinforce safer behaviors; refer patients for services such as substance abuse treatment; and facilitate partner notification, counseling, and testing (AII).

Patients should avoid sex practices that might result in oral exposure to feces (e.g., oral-anal contact) to reduce the risk for intestinal infections (e.g., cryptosporidiosis, shigellosis, campylobacteriosis, amebiasis, giardiasis, LGV serovars of C. trachomatis and hepatitis A) (BIII). Latex condom use alone might not reduce the risk for acquiring these fecal-orally transmitted pathogens. Persons who wish to reduce their risk for exposure might consider using dental dams or similar barrier methods for oral-anal and oral-genital contact, changing condoms after anal intercourse, and wearing latex gloves during digital-anal contact. Frequent washing of hands and genitals with warm soapy water during and after activities that might bring these body parts in contact with feces might further reduce risk for illness (CIII).

Hepatitis B vaccination is recommended for all susceptible (hepatitis B core antibody-negative) HIV-infected patients (AII). Hepatitis A vaccination is recommended for all susceptible men who have sex with men, as well as others with indications for hepatitis A virus vaccine (e.g., injection-drug users, persons with chronic liver disease or who are infected with hepatitis B and/or C) (AII).

Injection-Drug--Use Exposures

Injection-drug use is a complex behavior that puts HIV-infected persons at risk for hepatitis B virus and hepatitis C virus infection; additional, possibly drug-resistant strains of HIV; and other bloodborne pathogens. Providers should assess a person's readiness to change this practice and encourage activities to provide education and support directed at recovery. Patients should be counseled to stop using injection drugs (AIII) and to enter and complete substance abuse treatment, including relapse prevention programs (8) (AIII).

For patients who continue to inject drugs, health-care providers should advise them to adhere to the following practices:

  • Never reuse or share syringes, needles, water, or drug- preparation equipment; if injection equipment that has been used by other persons is shared, the implements should first be cleaned with bleach and water before use (AI).
  • Use only sterile syringes obtained from a reliable source (e.g., pharmacies or syringe-exchange programs) (BIII).
  • Use sterile (e.g., boiled) water to prepare drugs, and if this is not feasible, use clean water from a reliable source (e.g., fresh tap water); use a new or disinfected container (i.e., cooker) and a new filter (i.e., cotton) to prepare drugs (BIII).
  • Clean the injection site with a new alcohol swab before injection (BIII).
  • Safely dispose of syringes after one use (BIII).

All susceptible injection-drug--users should be vaccinated against hepatitis B (BII) and hepatitis A (BIII).

Environmental and Occupational Exposures

Certain activities or types of employment might increase the risk for exposure to tuberculosis. These include volunteer work or employment in health-care facilities, correctional institutions, and shelters for the homeless, and other settings identified as high risk by local health authorities. Decisions regarding whether to continue with such activities should be made in conjunction with a health-care provider and should be based on such factors as the patient's specific duties in the workplace, the prevalence of tuberculosis in the community, and the degree to which precautions designed to prevent the transmission of tuberculosis are taken in the workplace (BIII). These decisions will affect the frequency with which the patient should be screened for tuberculosis. Day care providers and parents of children in child care are at increased risk for acquiring cytomegalovirus infection, cryptosporidiosis, and other infections (e.g., hepatitis A, giardiasis) from children. The risk for acquiring infection can be diminished by optimal hygienic practices (e.g., handwashing) after fecal contact (e.g., during diaper changing) and after contact with urine or saliva (AII).

Occupations involving contact with animals (e.g., veterinary work and employment in pet stores, farms, or slaughterhouses) might pose a risk for cryptosporidiosis, toxoplasmosis, salmonellosis, campylobacteriosis, or Bartonella infection and other infections of concern to any immunocompromised host (e.g., leptospirosis, brucellosis, Capnocytophaga spp.). However, available data are insufficient to justify a recommendation against HIV-infected persons working in such settings.

Contact with young farm animals, specifically animals with diarrhea, should be avoided to reduce the risk for cryptosporidiosis (BII). Since soils and sands can be contaminated with Toxoplasma gondii and Cryptosporidium parvum, persons who have extended contact with these materials (e.g., gardening; playing in or cleaning sandboxes) should wash their hands thoroughly with soap and water following exposure (BIII). In areas where histoplasmosis is endemic, patients should avoid activities known to be associated with increased risk (e.g., creating dust when working with surface soil; cleaning chicken coops that are heavily contaminated with compost droppings; disturbing soil beneath bird-roosting sites; cleaning, remodeling or demolishing old buildings; and cave exploring) (CIII). In areas where coccidioidomycosis is endemic, when possible, patients should avoid activities associated with increased risk, including those involving extensive exposure to disturbed native soil (e.g., building excavation sites, during dust storms) (CIII).

Pet-Related Exposures

Health-care providers should advise HIV-infected persons of the potential risk posed by pet ownership. However, they should be sensitive to the possible psychological benefits of pet ownership and should not routinely advise HIV-infected persons to part with their pets (DIII). Specifically, providers should advise HIV-infected patients of the following precautions (9).


Veterinary care should be sought when a pet develops diarrheal illness. If possible, HIV-infected persons should avoid contact with animals that have diarrhea (BIII). A fecal sample should be obtained from animals with diarrhea and examined for Cryptosporidium, Salmonella, Campylobacter, and Shiga toxin-producing Escherichia coli (BIII).

When obtaining a new pet, HIV-infected patients should avoid animals aged <6 months (or <1 year for cats) and specifically animals with diarrhea (BIII). Because the hygienic and sanitary conditions in pet-breeding facilities, pet stores, and animal shelters are variable, patients should be cautious when obtaining pets from these sources. Stray animals should be avoided. Animals aged <6 months, and specifically those with diarrhea, should be examined by a veterinarian for Cryptosporidium, Salmonella, Campylobacter, and Shiga toxin-producing Escherichia coli (BIII).

Patients should wash their hands after handling pets, including before eating, and avoid contact with pets' feces to reduce the risk for cryptosporidiosis, salmonellosis, campylobacteriosis, and E. coli infection (BIII).

Patients should avoid all animal bite wounds to reduce the risk for infection. Patients should also not allow pets, particularly cats, to lick patients' open cuts or wounds. Patients should wash all animal bites, animal scratches, or wounds licked by animals promptly with soap and water (CIII) and seek medical attention (BIII). A 3- to 7-day course of antimicrobial therapy might be recommended if the wounds are moderate or severe, demonstrate crush injury and edema, involve the bones of a joint, involve a puncture of the skin near a joint, or involve a puncture of a joint directly (CIII).


Patients should be aware that cat ownership increases their risk for toxoplasmosis and Bartonella infection, and enteric infections (CIII). Patients who elect to obtain a cat should adopt or purchase an animal aged >1 year and in good health to reduce the risk for cryptosporidiosis, Bartonella infection, salmonellosis, campylobacteriosis, and E. coli infection (BII).

Litter boxes should be cleaned daily, preferably by an HIV-negative, nonpregnant person; if HIV-infected patients perform this task, their hands should be washed thoroughly afterward to reduce the risk for toxoplasmosis (BIII). To further reduce the risk for toxoplasmosis, HIV-infected patients should keep cats indoors, not allow them to hunt, and not feed them raw or undercooked meat (BIII). Although declawing is not usually advised, patients should avoid activities that might result in cat scratches or bites to reduce the risk for Bartonella infection (BII). Patients should also wash sites of cat scratches or bites promptly (CIII) and should not allow cats to lick patients' open cuts or wounds (BIII).

Care of cats should include flea control to reduce the risk for Bartonella infection (CIII). Testing cats for toxoplasmosis (EII) or Bartonella infection (DII) is not recommended.


Screening healthy birds for Cryptococcus neoformans, Mycobacterium avium, or Histoplasma capsulatum is not recommended (DIII).


Contact with reptiles (e.g., snakes, lizards, iguanas, and turtles) and chicks and ducklings should be avoided to reduce the risk for salmonellosis (BIII). Gloves should be used during aquarium cleaning to reduce the risk for infection with Mycobacterium marinum (BIII). Contact with exotic pets (e.g., nonhuman primates) should be avoided (CIII).

Food- and Water-Related Exposures

HIV-infected persons should avoid eating certain foods, including foods that might contain raw eggs (e.g., certain preparations of hollandaise sauce, Caesar and other salad dressings, certain mayonnaises, uncooked cookie and cake batter, and eggnog); raw or undercooked poultry, meat, seafood (raw shellfish in particular); unpasteurized dairy products; unpasteurized fruit juice; and raw seed sprouts (e.g., alfalfa sprouts or mung bean sprouts). Poultry and meat are safest when adequate cooking is confirmed with a thermometer (165º F [74º F]). If a thermometer is not used, the risk for illness is decreased by eating poultry and meat that have no trace of pink. However, color change of meat (e.g., absence of pink) does not always correlate with internal temperature. Produce items should be washed thoroughly (BIII); providers may wish to advise patients that produce is safest when cooked (CIII).

Cross-contamination of foods should be avoided. Uncooked meats should not be allowed to come in contact with other foods; hands, cutting boards, counters, and knives and other utensils should be washed thoroughly after contact with uncooked foods (BIII).

Although incidence of listeriosis is low, it is a serious disease that occurs unusually frequently among HIV-infected persons who are severely immunosuppressed. An immunosuppressed, HIV-infected person who wishes to reduce the risk for acquiring listeriosis as much as possible can do the following (CIII):

  • Avoid soft cheeses (e.g., feta, Brie, Camembert, blue-veined, and Mexican queso fresco cheese). Hard cheeses, processed cheeses, cream cheese, including slices and spreads, cottage cheese, or yogurt need not be avoided.
  • Cook leftover foods or ready-to-eat foods (e.g., hot dogs) until steaming hot before eating.
  • Avoid foods from delicatessen counters (e.g., prepared salads, meats, cheeses) or heat/reheat these foods until steaming before eating.
  • Avoid refrigerated pâtés and other meat spreads, or heat/ reheat these foods until steaming; canned or shelf-stable pâté and meat spreads need not be avoided.
  • Avoid raw or unpasteurized milk, including goat's milk, or foods that contain unpasteurized milk or milk products.

Patients should not drink water directly from lakes or rivers because of the risk for

cryptosporidiosis, giardiasis, and toxoplasmosis (AIII). Waterborne infection also might result from swallowing water during recreational activities. Patients should avoid swimming in water that is probably contaminated with human or animal waste and should avoid swallowing water during swimming (BII).

During outbreaks or in other situations in which a community boil-water advisory is issued, boiling water for >1 minute will eliminate the risk for acquiring cryptosporidiosis (AI). Using submicron, personal-use water filters (home/office types) or drinking bottled water might also reduce the risk (CIII). Available data are inadequate to support a recommendation that all HIV-infected persons boil or otherwise avoid drinking tap water in nonoutbreak settings. However, persons who wish to take independent action to reduce their risk for waterborne cryptosporidiosis might take precautions similar to those recommended during outbreaks. Such decisions are best made in conjunction with a health-care provider. Persons who opt for a personal-use filter or bottled water should be aware of the complexities involved in selecting the appropriate products, the lack of enforceable standards for destruction or removal of oocysts, product cost, and the difficulty of using these products consistently. Patients taking precautions to avoid acquiring cryptosporidiosis from drinking water should be advised that ice made from contaminated tap water also can be a source of infection (BII). Such persons should be aware that fountain beverages served in restaurants, bars, theaters, and other public places also might pose a risk, because these beverages, and the ice they might contain, are usually made from tap water. Nationally distributed brands of bottled or canned carbonated soft drinks are safe to drink. Commercially packaged, noncarbonated soft drinks and fruit juices that do not require refrigeration until after they are opened (i.e., those that can be stored unrefrigerated on grocery shelves) also are safe. Nationally distributed brands of frozen fruit juice concentrate are safe if they are reconstituted by users with water from a safe source. Fruit juices that must be kept refrigerated from the time they are processed to the time of consumption might be either fresh (i.e., unpasteurized) or heat treated (i.e., pasteurized); only juices labeled as pasteurized should be considered free of risk from Cryptosporidium and other disease agents. Other pasteurized beverages and beers also are considered safe. No data are available concerning survival of Cryptosporidium oocysts in wine.

Travel-Related Exposures

Travel, specifically to developing countries, might result in substantial risks of the exposure of HIV-infected persons to opportunistic pathogens, especially for patients who are severely immunosuppressed. Health-care providers or specialists in travel medicine should be consulted to help patients plan itineraries (BIII).

During travel to developing countries, HIV-infected persons are at a higher risk for foodborne and waterborne infections than they are in the United States. Foods and beverages, specifically raw fruits and vegetables, raw or undercooked seafood or meat, tap water, ice made with tap water, unpasteurized milk and dairy products, and items purchased from street vendors, might be contaminated. Items that are usually safe to consume include steaming hot foods, fruits that are peeled by the traveler, bottled (including carbonated) beverages, hot coffee or tea, beer, wine, and water brought to a rolling boil for >1 minute (AII). Treating water with iodine or chlorine might not be as effective as boiling but can be used, perhaps in conjunction with filtration, when boiling is not practical (BIII).

Waterborne infections might result from swallowing water during recreational activities. To reduce the risk for cryptosporidiosis, giardiasis, and toxoplasmosis, patients should avoid swallowing water during swimming and should not swim in water that might be contaminated (e.g., with sewage or animal waste) (BII).

Antimicrobial prophylaxis for traveler's diarrhea is not recommended routinely for HIV-infected persons traveling to developing countries (DIII). Such preventive therapy can have adverse effects and can promote the emergence of drug-resistant organisms. Nonetheless, studies (none involving an HIV-infected population) have reported that prophylaxis can reduce the risk for diarrhea among travelers. Under selected circumstances (e.g., those in which the risk for infection is high and the period of travel brief), the health-care provider and patient might weigh the potential risks and benefits and decide that antibiotic prophylaxis is warranted (CIII). For those persons to whom prophylaxis is offered, fluoroquinolones (e.g., ciprofloxacin [500 mg daily]) or rifaximin (200 mg daily) can be considered (CIII). Fluoroquinolones should not be administered to pregnant women and increasing resistance of bacterial enteric pathogens to fluoroquinolone might limit their future benefit for traveler's diarrhea. Prophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX) (one double-strength tablet daily) also has been demonstrated to be effective, but resistance to this drug is widespread, and it is no longer recommended in many tropical areas.

HIV-infected travelers to developing countries should carry a sufficient supply of an antimicrobial agent to be taken empirically if diarrhea occurs (BIII). One appropriate regimen is 500 mg of ciprofloxacin twice daily for 3--7 days. An alternative to fluoroquinolones in regions with fluoroquinolone resistance is azithromycin. Alternative antibiotics (e.g., azithromycin) should be considered as empirical therapy for use by pregnant women (CIII). Travelers should consult a physician if their diarrhea is severe and does not respond to empirical therapy, if their stools contain blood, if fever is accompanied by shaking chills, or if dehydration occurs. Antiperistaltic agents (e.g., diphenoxylate and loperamide) are used for treating diarrhea; however, they should not be used by patients with high fever or with blood in the stool, and their use should be discontinued if symptoms persist >48 hours (AII).

Travelers should be advised concerning other preventive measures appropriate for anticipated exposures (e.g., chemoprophylaxis for malaria, protection against arthropod vectors, treatment with immune globulin, and vaccination) (AII). They should avoid direct contact of the skin with soil or sand (e.g., by wearing shoes and protective clothing and by using towels on beaches) in areas where fecal contamination of soil is likely (BIII).

Live-virus vaccines should be avoided (EII). One exception is measles vaccine, which is recommended for nonimmune persons. However, measles vaccine is not recommended for persons who are severely immunosuppressed (DIII); immune globulin should be considered for measles-susceptible, severely immunosuppressed persons who are anticipating travel to measles-endemic countries (BIII). Another exception is varicella vaccine, which can be administered to asymptomatic nonimmunosuppressed adults who are susceptible to varicella virus infection (BII). Inactivated (killed) poliovirus vaccine should be used instead of oral (live) poliovirus vaccine, which is contraindicated for HIV-infected persons. Persons at risk for exposure to typhoid fever should be administered an inactivated parenteral typhoid vaccine instead of the live-attenuated oral preparation. Yellow fever vaccine is a live-virus vaccine with uncertain safety and efficacy among HIV-infected persons. Travelers with asymptomatic HIV infection who cannot avoid potential exposure to yellow fever should be offered vaccination. If travel to a zone with yellow fever is necessary and vaccination is not administered, patients should be advised of the risk, instructed in methods for avoiding the bites of vector mosquitoes, and provided a vaccination waiver letter.

Killed and recombinant vaccines (e.g., influenza, diphtheria-tetanus, rabies, hepatitis A, hepatitis B, Japanese encephalitis, meningococcal vaccines) should usually be used for HIV-infected persons just as they would be used for non-HIV--infected persons anticipating travel (BIII). Preparation for travel should include a review and updating of routine vaccinations, including diphtheria, tetanus, acellular pertussis, and influenza. Available cholera vaccine, which is not currently sold in the United States, is not recommended for travelers following a routine tourist itinerary, even if travel includes countries reporting cases of cholera (DII).

Travelers should be informed regarding other area-specific risks and instructed in ways to reduce those risks (BIII). Geographically focal opportunistic infections that pose an increased risk to HIV-infected persons include visceral leishmaniasis (a protozoan infection transmitted by the sandfly) and different fungal infections (e.g., Penicillium marneffei infection, coccidioidomycosis, and histoplasmosis). Several tropical and developing areas and some developed nations have high rates of tuberculosis.

CDC maintains a website accessible to travelers and their care providers at and regularly publishes recommendations for prevention of disease while traveling (CDC Health Information for International Travel 2008, a.k.a. the Yellow Book). This information can be found at the same website, which allows users to locate prevention recommendations according to geographic destination and to find updates on international disease outbreaks that might pose a health threat to travelers. A detailed review of concerns faced by immunocompromised persons traveling abroad is available at this website and in the Yellow Book (Chapter 9) (10).


  1. Fleming DT, Wasserheit JN. From epidemiological synergy to public health policy and practice: the contribution of other sexually transmitted diseases to sexual transmission of HIV infection. Sex Transm Infect 1999;75:3--17.
  2. Rottingen JA, Cameron DW, Garnett GP. A systematic review of the epidemiologic interactions between classic sexually transmitted diseases and HIV: how much really is known? Sex Transm Dis 2001;28:579--97.
  3. McClelland RS, Wang CC, Mandaliya K, et al. Treatment of cervicitis is associated with decreased cervical shedding of HIV-1. AIDS 2001;15:105--10.
  4. Cohen MS, Hoffman IF, Royce RA, et al. Reduction of concentration of HIV-1 in semen after treatment of urethritis: implications for prevention of sexual transmission of HIV-1. AIDSCAP Malawi Research Group. Lancet 1997 349:1868--73.
  5. Ghys PD, Fransen K, Diallo MO, et al. The associations between cervicovaginal HIV shedding, sexually transmitted diseases and immunosuppression in female sex workers in Abidjan, Côte d'Ivoire. AIDS 1997;11:85--93.
  6. CDC. Incorporating HIV prevention into the medical care of persons living with HIV. Recommendations of CDC, the Health Resources and Services Administration, the National Institutes of Health, and the HIV Medicine Association of the Infectious Diseases Society of America. MMWR 2003; 52(No. RR-12).
  7. CDC. Sexually transmitted diseases treatment guidelines, 2006. MMWR 2006;55(No.RR-11).
  8. CDC. HIV prevention bulletin: medical advice for persons who inject illicit drugs---May 9, 1997. Available at
  9. CDC. USPHS/IDSA guidelines for the prevention of oppurtunistic infections in persons infected with human immunodeficiency virus. MMWR 1999;48(No.RR-10).
  10. CDC. Health information for international travel, 2008. Atlanta, GA: US Department of Health and Human Services, Pubic Health Service. Available at 2007.

* Letters and Roman numerals in parentheses indicate the strength of the recommendation and the quality of evidence supporting it (see Box in Introduction).


ABG arterial blood gas

ABLC amphotericin B liquid complex

ACG atypical glandular cells

ACTG AIDS Clinical Trials Group

ACTs artemisinin-containing combination therapies

AFB acid-fast bacillus (pl. bacilli)

AFP alpha fetoprotein

AIN anal intraepithelial neoplasia

ALT alanine aminotransferase

Anti-HBc anti-hepatitis B core antibody

Anti-HBs anti-hepatitis B surface antibody

APR Antiretroviral Pregnancy Registry

ARN acute retinal necrosis

ART antiretroviral therapy

ARV antiretroviral

ASC-H atypical squamous cells, cannot rule out high grade lesions

ASC-US atypical squamous cells of undetermined significance

ASCCP American Society for Colposcopy and Cervical Pathology

AST aspartate aminotransferase

BA bacillary angiomatosis

BCG bacillus Calmette-Guérin

bDNA branched DNA

CAP community-acquired pneumonia

ccDNA closed circular DNA

CDC Centers for Disease Control and Prevention

CES-D Center for Epidemiologic Studies Depression Scale

CIN cervical intraepithelial neoplasia

CLEAR Collaborative Exchange on Antifungal Research

CMV cytomegalovirus

CNS central nervous system

CPT score Child-Pugh-Turcotte score

CSF cerebrospinal fluid

CT computed tomography

DNA deoxyribonucleic acid

DOT directly observed therapy

DRSP drug-resistant Streptococcus pneumoniae

EBV Epstein-Barr virus

EDTA ethylenediaminetetraacetic acid

EGD esophagogastroduodenoscopy

ELISA enzyme-linked immunosorbent assay

EMB ethambutol

ESLD end-stage liver disease

EVR early virologic response

FDA Food and Drug Administration

FLAIR fluid attenuated inversion recovery

HAART highly active antiretroviral therapy

HAV hepatitis A virus

HBeAG hepatitis B virus e antigen

HBIG hepatitis B virus immunoglobulin

HBsAg hepatitis B virus surface antigen

HBV hepatitis B virus

HCC hepatocellular carcinoma

HCV hepatitis C virus

HDV hepatitis delta virus

HHV-6 human herpesvirus 6

HHV-7 human herpesvirus 7

HHV-8 human herpesvirus 8

HIV human immunodeficiency virus

HIVMA HIV Medical Association

HPV human papillomavirus

HRA high-resolution anoscopy

HSIL high-grade squamous intraepithelial lesion

HSV-1 human herpes simplex virus type 1

HSV-2 human herpes simplex virus type 1

ICP intracranial pressure

ICU intensive care unit

IDSA Infectious Diseases Society of America

IDU intravenous- or injection-drug user

IFN interferon

IgG immunoglobulin G

IgM immunoglobulin M

IGRA interferon-gamma release assay

INH isoniazid

INR International Normalized Ratio

IRD immune reconstitution disease

IRIS immune reconstitution inflammatory syndrome

IRU immune recovery uveitis

IV intravenous

JCV JC virus

KOH potassium hydroxide

KS Kaposi's sarcoma

KSHV Kaposi's sarcoma-associated virus (aka HHV-8)

LEEP loop electrosurgical excision procedure

LSIL low-grade squamous intraepithelial lesion

LTBI latent tuberculosis infection

MAC Mycobacterium avium complex

MCD Multicentric Castleman's disease

MDR multidrug resistant (aka multiple drug-resistant)

MELD Model for End-stage Liver Disease

MRI magnetic resonance imaging

MSM men who have sex with men

MTCT mother-to-child transmission

MU million units

NAA nucleic acid amplification

NEP needle exchange program

NIH National Institutes of Health

NNRTI non-nucleoside reverse transcriptase inhibitor

NRTI nucleoside reverse transcriptase inhibitor

OARAC Office of AIDS Research Advisory Council

OI opportunistic infection

PCP Pneumocystis pneumonia (formerly P. carinii [now jirovecii] pneumonia)

PCR polymerase chain reaction

pegIFN pegylated interferon

PEL primary effusion lymphoma

PET positron emission tomography

PI protease inhibitor

PML progressive multifocal leukoencephalopathy

PORN progressive outer retinal necrosis

PPD purified protein derivative

PPV polysaccharide pneumococcal vaccine

PZA pyrazinamide

RBV ribavirin

RIF rifampin

RFB rifabutin

RNA ribonucleic acid

RPR rapid plasma reagin

RRP recurrent respiratory papillomatosis

RT-PCR reverse transcriptase-polymerase chain reaction

SAAG serum-ascites albumin gradient

SBP spontaneous bacterial peritonitis

SIRS systemic inflammatory response syndrome

SLE systemic lupus erythematosus

SP sulfadoxine-pyrimethamine

SPECT single-photon emission computed tomography

SVR sustained virologic response

TB tuberculosis

TE Toxoplasma gondii encephalitis

TMP-SMX trimethoprim-sulfamethoxazole

TSH thyroid stimulating hormone

TST tuberculin skin test

VAIN vaginal intraepithelial neoplasia

VDRL Venereal Disease Research Laboratory

VIN vulvar intraepithelial neoplasia

VZV varicella-zoster virus

WBC white blood cell

WHO World Health Organization

XDR extensively drug resistant

YMDD tyrosine-methionine-aspartate-aspartate

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Date last reviewed: 3/23/2009


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