TB testing stalls the green card medical exam when an applicant arrives without their history. A past positive with no records restarts testing, imaging and paperwork. The IGRA blood test is the I-693 screening standard. A chest X-ray follows a positive screen to rule out active disease.
Want to know why immigration exams get stalled? Look at tuberculosis testing. It’s the #1 bottleneck, and it’s almost entirely preventable.
Which TB tests are used for the immigration medical exam?
The old skin test (TST), the IGRA blood test, and the chest X-ray are not interchangeable. The IGRA is the screening standard for the I-693. The chest X-ray is the follow-up. It rules out active disease after a positive screen. A positive skin test from years ago may simply reflect BCG vaccination (a TB vaccine) or old exposure, not infection. Know which result you have and what it means. That is the difference between a one-visit exam and a six-week loop.
What happens if I tested positive for TB before?
Arrive without your history, and a past positive result restarts everything. New testing, new imaging, new paperwork, new waiting. Now arrive with the right records. That means past test results with dates, past chest X-ray reports, and records showing you finished latent TB treatment. Then a past positive can often be closed in a single visit.
What TB records should I bring to my exam?
Before booking, know your BCG history. Find any past TB test results. Pull imaging reports if you’ve ever had a chest X-ray for TB. Gather treatment records if you finished therapy. When imaging is required, our office sets up the prepaid chest X-ray directly. So radiology never becomes your scheduling problem.
Related reading: TB Testing and Treatment in the I-693 Exam · TB Screening in the Immigration Medical Exam · Anxiety and Your I-693 Exam Results · I-693 Immigration Medical Exam Cost — $390 Flat, St. Louis
Frequently Asked Questions
What’s the difference between the TB skin test and the IGRA?
The IGRA blood test is more specific. It is not thrown off by BCG vaccination. That is why it’s the standard screen for the I-693. The old skin test often gave false positives in applicants who had the BCG vaccine.
I tested positive for TB years ago. Will I be delayed?
Not necessarily. Bring your records: past results, imaging reports, and treatment records. With them, a past positive can often be resolved in a single visit.
Who arranges the chest X-ray if I need one?
We set up a prepaid chest X-ray. We put the radiology report into your sealed I-693 directly.
Why do I need a chest X-ray after a positive TB test?
The IGRA blood test is the screening standard for the I-693. When the screen is positive, the chest X-ray is the follow-up that rules out active disease. The two tests do different jobs. They are not interchangeable. When imaging is required, our office sets up the chest X-ray directly. So radiology never becomes your scheduling problem.
Can the BCG vaccine cause a positive TB test?
A positive skin test from years ago may simply reflect BCG vaccination or old exposure, not infection. That is why the IGRA blood test is the standard screen for the I-693. It is not thrown off by BCG vaccination. Know your BCG history before you book. Bring any past TB test results with dates.
How long does TB clearance take for the green card exam?
It depends on what you bring. Arrive without your history, and a past positive result restarts testing, imaging, paperwork and waiting. That can turn into a six-week loop. Arrive with past results, past chest X-ray reports and treatment records. Then a past positive can often be closed in a single visit.
Watch the full video above, and explore the rest of the series on our YouTube channel.
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Dr. Gurpreet Padda, MD — USCIS-Designated Civil Surgeon (CSID 111051)
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This article is educational information about the immigration medical examination process. It is not legal advice and does not create a physician–patient relationship. For legal questions about your case, consult a licensed immigration attorney.
Medically reviewed by Dr. Gurpreet Singh Padda, MD, MBA, MHP — USCIS-designated civil surgeon (CSID 111051), board certified in Anesthesiology, Pain Medicine, Interventional Pain Management, Addiction Medicine, and Obesity Medicine. Last reviewed September 2026.





