A patient scheduled a screening colonoscopy, confirmed by ins rep to be covered benefit at 100%. Based on a past history (over 10 yrs.) of benign colonic polyp, procedure was coded with Z86.010 (personal hx benign colonic polyp) as primary and sole diagnosis. I understand correct coding rationale to be: primary dx - Z12.11/screening colonoscopy, and secondary dx - Z86.010, due to polyps not being an active illness/condition and, further, because no polyps were found on colonoscopy. However someone told me that even if "screening" diagnosis Z12.11 is submitted as primary, if a "history of" diagnosis (i.e. Z86.010) is sequenced 2nd, 3rd, etc., the claim won't be processed as a 100% coverage benefit, unless patient has Medicare, since as of 2012, although pre-existing diagnoses (i.e. "hx of") are "covered" under the Affordable Care Act, the caveat is that if they are now life-time factors and if included anywhere in the diagnosis sequencing, even if in the extreme past/not currently active or concerning, and even with "screening" dx as primary, commercial payers assign the responsibility to patient's out-of-pocket. Can anyone clarify and/or validate this?