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I have an unusual situation related to the well-worn topic of when to use a/an before an acronym. We all know that the SOUND is what dictates which to use. So, for example, this is correct: "If an NOAC has been discontinued in the setting of acute UGI bleeding ... "
However, here is where I'm stumped. My acronym starts with the letter "U". A vowel right? But it's a vowel that sounds like a "Y" -- which either IS or ISN'T a vowel sound, depending on whom you ask. And this just sounds totally wrong to me: "Ten percent of rapid rectal bleeding has an UGI source." I desperately want to make it "a UGI source." If I'm not wrong, why am I not wrong? I will need to defend my decision to the higher ups!