Q: Can my wife return to the US while waiting for medical exam results?

We have been working on my wife's green card for almost two years. She has been living with me in the states for several months at a time on her tourist visa, returning to Mexico periodically as required in order not to overstay her visa. We received the letter notifying us of her interview at the consulate in Ciudad Juarez on April 30. She was visiting her family in Mexico, and decided to go ahead and get her medical exam in preparation for the interview. The clinic said she had a small spot on her lung, and though they were 99% certain it was nothing, they were required by the consulate to test for TB. They took specimens, and said it would be 10 weeks before the results were received. When she casually mentioned that she would be returning here to me in the States while she waited, the clinic personnel told her that her tourist visa may have been canceled when they informed the consulate that they were making the test for TB, and that her interview would probably be delayed by several months. So now we're worried that if she tries to fly home she may be turned back, and further worried that if she is turned back, it might affect her eligibility for the permanent resident visa, but we don't want to be separated for several months. Should she try to come home, or must she remain in Mexico until her new interview is scheduled?

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