Medical student's apparent celiac disease responded to giardiasis treatment

I'm wondering if the country he was living in doesn't do an endoscopy + biopsy when checking for celiac?

He should have come back negative on that.

My wife and son have Celiac, and I've been tested that way after an incident 15 years ago a lot like the patient in the article.

At the time the doctors were absolutely saying they wouldn't use a negative blood antibody test to determine a negative diagnosis, they wanted the biopsy.

I got tested for Giardia too. My symptoms started after a hiking/biking trip.

TFA: "But doctors never definitively diagnosed Johnson with celiac disease. His doctors wanted to do a biopsy to get a definite answer, but that would require eating gluten again, something Johnson wasn’t willing to chance"