Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Human Immunodeficiency Virus in Adults Testing AlgorithmHuman Immunodeficiency Virus in Infants Testing Algorithm
Immunodeficiency Evaluation for Chronic Infections in Adults and Older Children Testing Algorithm
Immunodeficiency Evaluation for Chronic Infections in Infants and Children Testing Algorithm
Clinical Background
Human immunodeficiency virus 1 (HIV-1) is thought to have originated as a zoonotic transmission from SIV-infected primates, while human immunodeficiency virus (HIV-2) is thought to have originated as a zoonotic transmission from Sooty Mangabeys.
- HIV-1 and HIV-2 are etiologic agents of acquired immunodeficiency syndrome (AIDS)
- HIV-1 accounts for the vast majority of all HIV infections in the U.S.
- Includes group M and at least 10 subtypes (A through J)
- Group O (for outlier)
- Group N (for non-M, non-O)
- Includes group M and at least 10 subtypes (A through J)
- HIV-2 is endemic to West Africa and rarely seen in U.S.
- Includes groups A through E
Transmission
- Primarily via sexual contact
- Parenterally and perinatally
- Tissue transplantation
- Can be prevented in 98% of infants of infected mothers by drug therapy during pregnancy, elective caesarian section and refraining from breastfeeding
- Blood-borne; not transmitted via saliva, insect vectors or household contacts
Clinical Presentation
- Acute symptoms include fever, fatigue, rash, headache, lymphadenopathy, pharyngitis, myalgias, nausea, vomiting, diarrhea and night sweats
See Also
Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Human Immunodeficiency Virus in Adults Testing AlgorithmHuman Immunodeficiency Virus in Infants Testing Algorithm
Immunodeficiency Evaluation for Chronic Infections in Adults and Older Children Testing Algorithm
Immunodeficiency Evaluation for Chronic Infections in Infants and Children Testing Algorithm
Diagnosis
Diagnosis
- Early diagnosis is crucial to institute highly active antiretroviral therapy (HAART)
- Reduces risk of devastating complications of full-blown AIDS
- Prevents further spread of HIV
- Viral spread from local inoculation occurs quickly
- 30 billion virus particles produced in first weeks of infection
- Antibodies detected approximately 22 to 27 days after acute infection
- Rapid screening tests are newly available (HIV ½ Stat-Pak, Multispot, Oraquick, Reveal, Sure Check HIV, Unigold)
- Overall sensitivity and specificity >99%
- Quantitative and drug resistance testing allows for monitoring during treatment
Refer to HIV topic at www.arupconsult.com for a table of Comparisons of STI Screening Recommendations for Sexually Active Nonpregnant Women
Refer to HIV topic at www.arupconsult.com for a table of Comparisons of STI Screening Recommendations for Pregnant Women
Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Human Immunodeficiency Virus in Adults Testing AlgorithmHuman Immunodeficiency Virus in Infants Testing Algorithm
Immunodeficiency Evaluation for Chronic Infections in Adults and Older Children Testing Algorithm
Immunodeficiency Evaluation for Chronic Infections in Infants and Children Testing Algorithm
| Tests |  |
Tests generally appear in the order most useful for common clinical situations
| Test name: Human Immunodeficiency Virus 1 Antibody, Confirmation |
| ARUP #: 0020284 |
| Methodology: Western Blot |
| Use: If screening test is repeatedly reactive, the laboratory automatically performs Western Blot |
| Limitations: Do not use for blood donor screening, associated re-entry protocols or for screening human cell and cellular and tissue-based products (HCT/P) |
| Follow-up: |
| Test name: Human Immunodeficiency Virus 1 Antibody with Reflex to Confirmation by Western Blot |
| ARUP #: 0051154 |
| Methodology: Enzyme Immunoassay/Western Blot |
| Use: Screen for presence of HIV-1 infection |
| Limitations: |
| Follow-up: |
| Test name: Human Immunodeficiency Virus 1,2 Combined Antibodies with Reflex to HIV-1 Confirmation by Western Blot |
| ARUP #: 0051160 |
| Methodology: Enzyme Immunoassay/Western Blot |
| Use: Screen for presence of HIV infection Screen for antibodies against HIV-1 and HIV-2 |
| Limitations: |
| Follow-up: |
| Test name: Human Immunodeficiency Virus 2 Antibody Confirmation by Immunoblot |
| ARUP #: 0093272 |
| Methodology: Immunoblot |
| Use: Confirm positive screening results |
| Limitations: |
| Follow-up: |
| Test name: Human Immunodeficiency Virus 1 RNA Quantitative bDNA |
| ARUP #: 0020466 |
| Methodology: Branched Chain DNA |
| Use: Use with clinical presentation as indicator of disease prognosis Use as aid in assessing viral response to antiretroviral treatment |
| Limitations: A result less than 75 HIV copies/ML does not rule out the presence of inhibitors in the patient specimen or HIV-1 virus RNA concentrations below the limit of detection by the assay |
| Follow-up: |
| Test name: Human Immunodeficiency Virus 1 DNA PCR, Qualitative |
| ARUP #: 0093061 |
| Methodology: Polymerase Chain Reaction |
| Use: Detects HIV-1 proviral DNA in infants (before 48 hours, 1-2 months and 3-6 months of age) |
| Limitations: Do not use umbilical cord blood due to contamination with mother’s blood |
| Follow-up: |
| Test name: Human Immunodeficiency Virus 1 RNA Quantitative Real-Time PCR |
| ARUP #: 0055598 |
| Methodology: Real-Time Polymerase Chain Reaction |
| Use: Use in conjunction with clinical presentation as indicator of disease prognosis Use as aid in assessing viral response to antiretroviral treatment |
| Limitations: False-positive results may occur; care should be taken when interpreting, especially for seronegative patientsA result less than 48 HIV copies/ML does not rule out the presence of inhibitors in the patient specimen or HIV-1 virus RNA concentrations below the limit of detection by the assay |
| Test name: Human Immunodeficiency Virus 2 Antibody with Reflex to Confirmation |
| ARUP #: 0051250 |
| Methodology: Enzyme Immunoassay/Immunoblot |
| Use: Screen for presence of HIV-2 infection in patient with epidemiologic link to Africa |
| Limitations: |
| Follow-up: Repeatedly reactive EIA results will be confirmed by immunoblot testing |
| Test name: Lymphocyte Subset Panel 1 - CD4 Absolute Count Only |
| ARUP #: 0095854 |
| Methodology: Flow Cytometry |
| Use: Monitor treatment efficacy Determine T-cell (CD4) levels to establish decision points for initiating P. jiroveci prophylaxis, antiviral therapy Order concurrently with HIV viral load monitoring tests |
| Limitations: |
| Follow-up: The Public Health Service (PHS) has recommended that Helper T-cell levels be monitored every 3 to 6 months in all HIV-infected persons Other lymphocyte panels are available See list of additional tests available |
| Test name: Human Immunodeficiency Virus 1, Genotyping |
| ARUP #: 0055670 |
| Methodology: Reverse Transcription Polymerase Chain Reaction/DNA Sequencing |
| Use: Detect changes in the viral genome that are associated with drug resistance Use in conjunction with CD4 measurement to monitor treatment efficacy Test requires specimens with HIV-1 RNA plasma levels of greater than 1,000 copies/mL |
| Limitations: Treatment failure can be caused by factors other than drug resistance; therefore, the interpretation of resistance genotyping results must be done in conjunction with other clinical and laboratory information Comparisons between assays performed in different laboratories are not recommended since no method standardization exists among HIV-1 drug resistance testing Results from different test methods/algorithms may provide different resistance interpretation The absence of resistance mutations does not rule out the presence of reservoirs of resistant viruses that cannot be detected by these tests Some specimens with HIV-1 RNA plasma levels greater than 1,000 copies/mL may not provide adequate data due to polymorphisms in the priming areas of the genome This test does not detect HIV-1 populations that are less than approximately 20 percent of the total population |
Additional Tests Available
| Test name: Human Immunodeficiency Virus1 RNA Quantitative Real-Time PCR with Reflex to Human Immunodeficiency Virus 1 Genotyping |
| ARUP #: 0051660 |
| Methodology: Real-Time Polymerase Chain Reaction |
| Comments: Panel testUse with clinical presentation as an indicator of disease prognosis and assess viral response to antiretroviral treatment |
| Test name: Human Immunodeficiency Virus 1 RNA Quantitative bDNA with Reflex to Human Immunodeficiency Virus 1 Genotyping |
| ARUP #: 0051664 |
| Methodology: Branched Chain DNA/Genotyping |
| Comments: Panel testUse with clinical presentation as an indicator of disease prognosis and assess viral response to antiretroviral treatment |
| Test name: Lymphocyte Subset Panel 2 - CD4 Percent & Absolute |
| ARUP #: 0095885 |
| Methodology: Flow Cytometry |
| Comments: |
| Test name: Lymphocyte Subset Panel 3 - T-Cell Subsets (CD4 & CD8), Absolute Counts Only |
| ARUP #: 0095853 |
| Methodology: Flow Cytometry |
| Comments: |
| Test name: Lymphocyte Subset Panel 4 - T-Cell Subsets Percent & Absolute, Whole Blood |
| ARUP #: 0095950 |
| Methodology: Flow Cytometry |
| Comments: |
| Test name: Lymphocyte Subset Panel 5 - Total Lymphocyte Enumeration |
| ARUP #: 0095892 |
| Methodology: Flow Cytometry |
| Comments: |
| Test name: Lymphocyte Subset Panel 6 - Total Lymphocyte Enumeration with CD45RA & CD45RO |
| ARUP #: 0095862 |
| Methodology: Flow Cytometry |
| Comments: |
| Test name: Erythropoietin |
| ARUP #: 0050227 |
| Methodology: Chemiluminescent Immunoassay |
| Comments: |
Additional Information
For HIV-1 anti-retroviral drugs genotyping analysis, refer to Human Immunodeficiency Virus 1, Antiretroviral Drug Resistance Testing - HIV Drug Resistance topic.
References
Guidelines
Adolescents and human immunodeficiency virus infection: the role of the pediatrician in prevention and intervention. American Academy of Pediatrics - Medical Specialty Society. 2001 Jan. 3 pages. NGC:002002Hammer SM, Saag MS, Schechter M, Montaner JS, Schooley RT, Jacobsen DM, Thompson MA, Carpenter CC, Fischl MA, Gazzard BG, Gatell JM, Hirsch MS, Katzenstein DA, Richman DD, Vella S, Yeni PG, Volberding PA. Treatment for adult HIV infection: 2006 recommendations of the International AIDS Society-USA panel. JAMA . 2006 ;296 (7 ):827-843 . Primary care guidelines for the management of persons infected with human immunodeficiency virus: recommendations of the HIV Medicine Association of the Infectious Diseases Society of America. Infectious Diseases Society of America - Medical Specialty Society. 2004 Sep 1. 21 pages. NGC:003793Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. Centers for Disease Control and Prevention - Federal Government Agency [U.S.]. 2001 Nov 9 (revised 2006 Sep 22). 17 pages. NGC:005246
Cited References
Meyers, D., Wolff, T., Gregory, K., et al. USPSTF Recommendations for STI Screening. Originally published in Am Fam Physician 2008;77:819-824. Agency for Healthcare Research and Quality, Rockville, MD. (Accessed on July 15, 2008)
General References
References from the ARUP Institute for Clinical and Experimental Pathology Research®
Medical Reviewers
Hillyard, David R., M.D. Medical Director, Molecular Infectious Diseases at ARUP Laboratories; Associate Professor, Pathology, University of Utah
Litwin, Christine, M.D. Medical Director, Immunology at ARUP Laboratories; Professor, Clinical Pathology, University of Utah
Reimer, Larry G., M.D. Medical Director, Microbiology, Veteran's Affair Hospital; Professor of Pathology and Associate Dean for Curriculum and GME, University of Utah School of Medicine
Comprehensive Review: November 2007
Last Update: September 2008
