Pacific · TB Gold Blood Test – QuantiFERON Tuberculosis Lab Test
TB Gold Blood Test – QuantiFERON Tuberculosis Lab Test in California
Below is a plain-language overview of the tb gold blood test – quantiferon tuberculosis lab test. A TB Gold blood test helps detect tuberculosis infection by measuring your immune system's response to TB bacteria.
Lab requirements in California
Here is what you need before ordering and completing the TB Gold Blood Test – QuantiFERON Tuberculosis Lab Test in CA. Review each item and confirm the details with the collection lab.
- Physician's order
- Included. A physician's order is required for lab testing and is provided for you by our partner's physicians — no referral from your own doctor is needed.
- Fasting
- Some tests require fasting or avoiding certain foods or drinks beforehand. You will be informed when you order — confirm the details with the collection lab.
- Preparation
- No special preparation is usually needed, but follow any instructions provided by the collection lab. They may have specific guidelines about timing or other factors.
- Sample & visit
- A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
- Identification
- Bring the lab requisition form from your account. The collection lab may also ask for a government-issued photo ID.
- Turnaround
- 1-3 business days
- Availability
- Our partner lab does not serve ND, RI, NY, NJ, MD or HI. Confirm availability for your location with the collection lab.
Before you go
- Order your test before visiting a lab, then use the requisition form in your account.
- Print the requisition form, or fax it to the lab directly from your account.
- No scheduling is needed — visit the collection lab during its normal business hours.
- A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
- Bring a government-issued photo ID in case the lab requests it.
- Results are posted to your secure account within 1–3 business days.
Requirements are summarized from our partner lab's published policies. Preparation and availability can change — confirm current instructions with the collection lab before your visit.
What this test is
This test, often called a QuantiFERON TB test, is a blood test that checks whether you have been infected with the bacteria that cause tuberculosis. It works by measuring the release of a substance called interferon-gamma from your white blood cells when they are exposed to TB proteins.
What it measures
- Interferon-gamma — A substance released by immune cells in response to TB proteins
- Nil control — A baseline measurement to account for background interferon-gamma
- Mitogen control — A positive control to confirm that your immune cells are functioning properly
- TB antigen response — The level of interferon-gamma produced when your blood is exposed to TB-specific proteins
What the test involves
A healthcare professional will collect a blood sample from a vein in your arm using a standard blood draw. The sample is then sent to a laboratory for analysis.
Why it is often ordered
A clinician may order this test if you have symptoms of TB, have been in close contact with someone who has TB, or need screening because you work or live in a high-risk setting. It is also used before starting certain medications that can affect TB.
Preparation
No special preparation is usually needed, but follow any instructions provided by the collection lab. They may have specific guidelines about timing or other factors.
How results are reported
Results are typically reported as positive, negative, or indeterminate, indicating whether a TB infection is likely. Reference ranges and interpretation can vary by laboratory, so your clinician will explain what your results mean.
Before you go
- Whether any medications you take could affect the test results
- If there are any special timing or handling instructions for the sample
- How and when you will receive your results
Cities
TB Gold Blood Test – QuantiFERON Tuberculosis Lab Test in California communities
Choose your city for local context and to order this test.