Welcome to the Interpretive Guide. This Guide provides information relating to test selection, utilization, and interpretation. The Guide is continually updated by adding new information and modifying posted information. All information is based on peer-reviewed publications, practice guidelines, or other reputable sources and is intended to be without promotional considerations.

Reference ranges are provided for your convenience and are based on Quest Diagnostics data or published references (where cited). These ranges can serve as a guideline; however, interpretation of patient results should be based on the ranges provided in the patient report.

Included in the Interpretive Guide are four types of information:

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Test highlights and summaries provide a review of clinical use and background, methodology, specimen requirements, and interpretation of the test.

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Test guides provide testing algorithms or other information that assists in appropriate test selection.

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Technology guides compare multiple technologies provided for the same or similar analytes.

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What's New

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HIV-1 Drug Resistance Testing is useful when selecting a new treatment regimen for patients with virologic failure. An algorithm to guide drug resistance test selection for the treatment-experienced patient is included.

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The Integrated Screening tests are used to screen pregnant women for fetal neural tube defects and Down syndrome and to identify pregnancies at high risk of trisomy 18. Multiple integrated screens are described.

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HPV Genotypes 16 and 18 cause more than half of the cervical cancer cases; thus, risk is substantial in women with these genotypes. In addition to risk assessment, HPV genotype testing can help guide patient management when used in conjunction with cytology results.

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The Aldosterone/PRA Ratio is used to screen for primary aldosteronism (PA). An algorithm for diagnosis and management of PA is provided.

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The Fibrinolysis Comprehensive Panel is used to identify fibrinolytic abnormalities in individuals with either excessive bleeding (especially in response to injury, surgery, or fibrinolytic therapy) or thrombosis.

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The HIV-1 Integrase Genotype test is used to predict HIV-1 resistance to the integrase inhibitor raltegravir and to monitor transmission of raltegravir-resistant HIV-1.

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Unlike seasonal flu viruses, the 2009 H1N1 influenza virus has continued to infect people in the U.S. during the summer months, and the pandemic is expected to continue into the normal flu season. The Influenza A H1N1 (2009) Real-Time RT-PCR test is used as an aid in the detection and differentiation of seasonal influenza A virus infection and 2009 H1N1 influenza virus infection.