Test DIRECTORY

Explore our comprehensive menu of laboratory tests designed to support accurate, reliable results across every specialty.

APG LAB's test directory provides a comprehensive list of specialty and general laboratory testing services.

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
There are currently 5 names in this directory beginning with the letter Q.
Q Fever Antibodies, IgG

Synonyms

  • Coxiella burnetii Antibodies

Test Includes

Titer of both phase I and phase II responses

Expected Turnaround Time

2 - 5 days

Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.

Related Documents

Specimen Requirements

Specimen

Serum

Volume

0.4 mL

Minimum Volume

0.2 mL

Container

Red-top tube or gel-barrier tube

Storage Instructions

Maintain specimen at room temperature.

Causes for Rejection

Hemolysis; lipemia; gross bacterial contamination

Test Details

Use

Aid in the differential diagnosis for Q fever

Methodology

Indirect fluorescent antibody (IFA)

Reference Interval

Negative: <1:16
QuantiFERON®-TB Gold Plus

Synonyms

  • Interferon-gamma Release Assay (IGRA) for Mycobacterium tuberculosis
  • QFT-Plus

Special Instructions

QuantiFERON is time-sensitive and specimens must be received in the laboratory within 14 hours of collection. Specimen collection times will vary depending on logistics from the blood draw location to a LabCorp lab. This test requires a special collection kit that may not be available at all PSCs. To submit QuantiFERON specimens that are client-incubated, order QuantiFERON®-TB Gold Plus (Client Incubated) (Test No. 182893).

Expected Turnaround Time

2 - 5 days

Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.

Related Documents

For more information, please view the literature below. TB or not TB? Microbiology Specimen Collection and Transport Guide

Specimen Requirements

Specimen

Whole blood

Volume

1 mL x four tubes in QuantiFERON-TB Gold Plus kit

Minimum Volume

1 mL x four tubes in QuantiFERON-TB Gold Plus kit

Container

The QuantiFERON®-TB Gold Plus collection kit contains the instructions for the collection and handling of (one each): (1) gray-top (with white ring), uncoated (nil); (2) green cap with white ring, TB1 tube; (3) yellow cap with white ring, TB2 tube; (4) purple top with white ring, mitogen-coated. A high-altitude kit is also available for locations between 3350 and 6150 feet; a cap with a yellow ring differentiates the tubes.

Collection

Blood collection tubes should be at room temperature at the time of collection. Refer to collection instructions included with draw kit. Special specimen collection kit contains four gel-barrier tubes as noted above. All four tubes are required for a single test result. Each tube is designed to draw only 1 mL and fill time may be longer than other blood collection tubes. Because of the limited vacuum in these tubes, use a needle and holder (not a butterfly) to collect QuantiFERON® specimens. If a butterfly is required, first collect other required tubes or use another Vacutainer® tube to purge the butterfly line of air and then proceed with drawing the QuantiFERON tubes. Fill tubes to the black fill line on the tube. If tubes are underfilled or overfilled (see kit insert), immediately collect a replacement tube. Following proper fill, label the tubes appropriately and shake tubes 10 times firmly enough to ensure the entire surface of the tube is coated with blood cells to solubilize the antigen on the tube walls. After shaking, the volume may fall below the fill line. Do not centrifuge or refrigerate specimens. Return each of the four properly filled, labeled, and shaken tubes to the box labeled "QFT kit." Seal the top by removing tape from the adhesive. To preserve cellular viability, specimens should be collected and sent the same day, at room temperature, so as to arrive at the lab as soon as possible and within 14 hours of collection.

Storage Instructions

Maintain specimen at room temperature for four tube collection kit. Stability: Kit must be incubated within 16 hours of collection.

Causes for Rejection

Expired collection tubes. Four tube QuantiFERON collection kit: Specimen centrifuged, refrigerated, or frozen; specimen more than 14 hours old on receipt by lab; receipt of three tube collection kit

Test Details

Use

QuantiFERON-TB Gold Plus is an in vitro diagnostic test using a peptide cocktail of CD4+ and CD8+ T cell antigens to stimulate cells in heparinized whole blood. Detection of interferon-gamma by enzyme-linked immunosorbent assay (ELISA) is used to identify in vitro responses to these peptide antigens that are associated with Mycobacterium tuberculosis infection. QuantiFERON-TB Gold Plus is an indirect test for M. tuberculosis infection (including disease) and is intended for use in conjunction with risk assessment, radiography, and other medical and diagnostic evaluations.

Limitations

A negative QFT-Plus result does not preclude the possibility of M. tuberculosis infection or tuberculosis disease: false negative results can be due to stage of infection, co-morbid conditions that affect immune function, incorrect handling of the blood collection tubes following venipuncture, incorrect performance of the assay, or other individual immunological variables. Heterophile antibodies or non-specific interferon-gamma production from other inflammatory conditions may mask specific responses to CD4+ and CD8+ T cell antigens. A positive QFT-Plus result should not be the sole or definitive basis for determining infection with M. tuberculosis. Incorrect performance of the assay may cause false-positive results. A positive QFT-Plus result should be followed by further medical evaluation for active tuberculosis disease.

Methodology

Whole blood interferon-gamma test measuring responses to CD4+ and CD8+ T cell antigens
QuantiFERON®-TB Gold Plus (Client Incubated)

Synonyms

  • Interferon-gamma Release Assay (IGRA) for Mycobacterium tuberculosis
  • QFT-Plus

Special Instructions

This test is time-sensitive. Specimens must be incubated at 37°C for 16 to 24 hours prior to transport to LabCorp and specimens must be received in the laboratory within 70 hours after incubation by the client (no more than 94 hours from the time of collection). Specimen collection times will be dependent on logistics from the incubating location to a LabCorp lab. To submit QuantiFERON-TB Gold Plus specimens that are not client incubated prior to submission, order QuantiFERON®-TB Gold Plus (Test No. 182879).

Expected Turnaround Time

2 - 5 days

Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.

Related Documents

For more information, please view the literature below. TB or not TB? Microbiology Specimen Collection and Transport Guide

Specimen Requirements

Specimen

Whole blood

Volume

1 mL x four tubes in QuantiFERON-TB Gold Plus kit

Minimum Volume

1 mL x four tubes in QuantiFERON-TB Gold Plus kit

Container

The QuantiFERON®-TB Gold Plus collection kit contains the instructions for the collection and handling of (one each): (1) gray-top (with white ring), uncoated (nil); (2) green cap with white ring, TB1 tube; (3) yellow cap with white ring, TB2 tube; (4) purple top with white ring, mitogen-coated. A high altitude kit is also available for locations between 3350 and 6150 feet; a cap with a yellow ring differentiates the tubes.

Collection

Blood collection tubes should be at room temperature at the time of collection. Refer to collection instructions included with draw kit. Special specimen collection kit contains four gel-barrier tubes as noted above. All four tubes are required for a single test result. Each tube is designed to draw only 1 mL and fill time may be longer than other blood collection tubes. Because of the limited vacuum in these tubes, use a needle and holder (not a butterfly) to collect QuantiFERON® specimens. If a butterfly is required, first collect other required tubes or use another Vacutainer® tube to purge the butterfly line of air and then proceed with drawing the QuantiFERON tubes. Fill tubes to the black fill line on the tube. If tubes are underfilled or overfilled (see kit insert), immediately collect a replacement tube. Following proper fill, label the tubes appropriately and shake tubes 10 times firmly enough to ensure the entire surface of the tube is coated with blood cells to solubilize the antigen on the tube walls. After shaking, the volume may fall below the fill line. Do not centrifuge or refrigerate specimens. Return each of the four properly filled, labeled, and shaken tubes to the box labeled "QFT kit." Seal the top by removing tape from the adhesive.

Storage Instructions

Before incubation at 37°C, maintain specimen at room temperature. Stability: Kit must be incubated within 16 hours of collection. After incubation, maintain specimen at room temperature (17°C to 27°C). Do not centrifuge, refrigerate, or ship tubes on ice.

Causes for Rejection

Expired collection tubes; specimen centrifuged, refrigerated, or frozen; specimen more than 94 hours old on receipt by lab; receipt of three tube collection kit

Test Details

Use

QuantiFERON-TB Gold Plus is an in vitro diagnostic test using a peptide cocktail of CD4+ and CD8+ T cell antigens to stimulate cells in heparinized whole blood. Detection of interferon-gamma by enzyme-linked immunosorbent assay (ELISA) is used to identify in vitro responses to these peptide antigens that are associated with Mycobacterium tuberculosis infection. QuantiFERON-TB Gold Plus is an indirect test for M. tuberculosis infection (including disease) and is intended for use in conjunction with risk assessment, radiography, and other medical and diagnostic evaluations.

Limitations

A negative QFT-Plus result does not preclude the possibility of M. tuberculosis infection or tuberculosis disease: false negative results can be due to stage of infection, co-morbid conditions that affect immune function, incorrect handling of the blood collection tubes following venipuncture, incorrect performance of the assay, or other individual immunological variables. Heterophile antibodies or non-specific interferon-gamma production from other inflammatory conditions may mask specific responses to CD4+ and CD8+ T cell antigens. A positive QFT-Plus result should not be the sole or definitive basis for determining infection with M. tuberculosis. Incorrect performance of the assay may cause false-positive results. A positive QFT-Plus result should be followed by further medical evaluation for active tuberculosis disease.

Methodology

Whole blood interferon-gamma test measuring responses to CD4+ and CD8+ T cell antigens
Quetiapine, Serum or Plasma

Synonyms

  • Seroquel®

Expected Turnaround Time

5 - 10 days

Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.

Specimen Requirements

Specimen

Serum or plasma

Volume

3 mL

Minimum Volume

0.6 mL

Container

Red-top tube or green-top (heparin) tube. Gel-barrier tubes not recommended.

Collection

Serum or plasma should be separated from cells within two hours of venipuncture. Submit serum or plasma in a plastic transport tube.

Storage Instructions

Submission/transport (<3 days): Room temperature. For storage beyond three days, specimen should be refrigerated or frozen.

Patient Preparation

Trough levels are most reproducible.

Causes for Rejection

Gel-barrier tubes

Test Details

Use

Therapeutic drug management

Methodology

Liquid chromatography/tandem mass spectrometry (LC/MS-MS)

Reference Interval

Expected steady-state quetiapine plasma levels in patients receiving recommended daily dosages: 100−1000 ng/mL.
Quinidine, Serum or Plasma

Expected Turnaround Time

1 - 3 days

Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.

Specimen Requirements

Specimen

Serum or plasma

Volume

1 mL

Minimum Volume

0.3 mL

Container

Red-top tube or green-top (heparin) tube. Do not use a gel-barrier tube. The use of gel-barrier tubes is not recommended due to slow absorption of the drug by the gel. Depending on the specimen volume and storage time, the decrease in drug level due to absorption may be clinically significant.

Collection

Transfer separated serum or plasma to a plastic transport tube. Peak: quinidine sulfate: 11/2 hours after dose, quinidine gluconate: four hours after dose; trough: immediately prior to next dose; after change in dose: one to two days.

Storage Instructions

Room temperature

Stability Requirements

Temperature Period
Room temperature 14 days
Refrigerated 14 days
Frozen 14 days
Freeze/thaw cycles Stable x3

Causes for Rejection

Gel-barrier tube; severe hemolysis; lipemia; icteric specimen

Test Details

Use

This Class 1A drug is useful in both supraventricular and ventricular arrhythmias. It major uses are to maintain sinus rhythm after conversion of atrial flutter or fibrillation, to prevent ventricular tachycardia, and for long-term prophylaxis in patients with AV nodal reentrant tachycardia and automatic atrial tachycardia. Quinidine also has been used to prevent symptomatic premature supraventricular and ventricular complexes. Because it slows conduction and prolongs the refractory period of the accessory pathway and suppresses automaticity of ectopic pacemakers, quinidine may prevent recurrences of paroxysmal supraventricular tachycardia caused by reentry over a concealed pathway or AV reciprocating tachycardia associated with the Wolff-Parkinson-White syndrome. It also may slow the ventricular response to atrial flutter or fibrillation in the preëxcitation syndrome. Quinidine is often preferred to procainamide for long-term therapy because elevated antinuclear antibody titers and drug-induced lupus are common during prolonged therapy with procainamide.

Methodology

Immunoassay (IA)

Reference Interval

Therapeutic: 2.0−5.0 μg/mL

Critical Value

Potentially toxic: >5.0 μg/mL

Additional Information

Optimal resampling time after change in dosage is one to two days. Biologic half-life is about six to eight hours. Doses of quinidine >250 mg/day result in increased serum digoxin concentrations about 2.5 times the digoxin concentration before quinidine was added. The new steady-state of digoxin concentration occurs in 7 to 14 days, with signs of toxicity beginning to appear in three to seven days after initiation of quinidine therapy. Therefore, serum digoxin concentrations should be measured before initiation of quinidine therapy and again in four to six days. Measure trough because of variability of peak interval. Renal failure prolongs apparent half-life, perhaps through accumulation of fluorescent metabolites. Severe heart failure also prolongs half-life, as does liver disease. Concomitant administration of phenytoin increases hepatic metabolism, and therefore decreases half-life and serum quinidine concentrations. Clearance may be diminished in the elderly.1

Common Lab Tests

Complete Blood Count

LEARN MORE

This test, also known as a CBC, is the most common blood test performed. It measures the types and numbers of cells in the blood, including red and white blood cells and platelets. This test is used to determine general health status, screen for disorders and evaluate nutritional status. It can help evaluate symptoms such as weakness, fatigue and bruising, and can help diagnose conditions such as anemia, leukemia, malaria and infection.

Prothrombin Time

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Also known as PT and Pro Time, this test measures how long it takes blood to clot. This coagulation test measures the presence and activity of five different blood clotting factors. This test can screen for bleeding abnormalities, and may also be used to monitor medication treatments that prevent the formation of blood clots.

Basic Metabolic Panel

LEARN MORE

This test measures glucose, sodium, potassium, calcium, chloride, carbon dioxide, blood urea nitrogen and creatinine which can help determine blood sugar level, electrolyte and fluid balance as well as kidney function. The Basic Metabolic Panel can help your doctor monitor the effects of medications you are taking, such as high blood pressure medicines, can help diagnose certain conditions, or can be part of a routine health screening. You may need to fast for up to 12 hours before this test.

Lipid

Panel

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The lipid panel is a group of tests used to evaluate cardiac risk. It includes cholesterol and triglyceride levels.

Liver Panel

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The liver panel is a combination of tests used to assess liver function and establish the possible presence of liver tumors.

Hemoglobin A1C

LEARN MORE

This test is used to diagnose and monitor diabetes.

Urinalysis

LEARN MORE

Often the first lab test performed, this is a general screening test used to check for early signs of disease. It may also be used to monitor diabetes or kidney disease.

Cultures

LEARN MORE

Cultures are used to test for diagnosis and treatment of infections. Illnesses such as urinary tract infections, pneumonia, strep throat, MRSA and meningitis can be detected and tested for appropriate antibiotic treatment.

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