Wiki Annoyed with Z12.11 Denials for Colonoscopies!!!! PLEASE HELP!!!


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Hello Fellow Coders!!
I've read sooooo many AAPC forums regarding how to appropriately code Colonoscopies and related procedures to avoid Z12.11 dx denials with or without findings--because we have been receiving HUNDREDS of these denials!!!

First I've read to code the findings as primary then code Z12.11 secondary, etc.

But then I've read to code Z12.11 as primary then code findings secondary, etc.

Other forums I read to use modifiers 33 or PT for 45378 for commercial and G0105 or G01210 for Medicare.

I've been soooo confused and frustrated over this dilemma!!!

I just need to know how to appropriately code dx Z12.11 with Colonoscopies with the appropriate modifiers to end these never-ending denials!!!!

A few coders provided the following links:

...which lead me to the following link for AGA coding guide for CRC screening:

The problem is the links providing CPT and dx coding info for Colonoscopy screenings still use ICD-9 codes instead of ICD-10 codes, so I'm thinking how accurate is this info provided as to how to appropriately code Colonoscopy screenings to prevent Z12.11 dx denials??

Please HELP!!! :)

P.S. Can someone also provide accurate info as to how to appropriately dx code Colonoscopy screenings for E/M codes because these are denying as well.

Thanks soooooo much in advance for your assistance--greatly appreciate it!!!
Hi She803,
Ok I read physician documentation which hopefully he or she will put reason doing the colonoscopy. Is it due to K21.9, dx K63, dx K92 K52.9 K57 K64 or just dx R10, dxR11 or dx R15 or K59 problems. If it is one of those problems bill that first on claim, then Z dx code of Z12.11 or Z11.0 orZ13.811 or Z86.010 as supported. Also if pt has colon polyps doc removes polyps list that first on the claim. Ensure read lab results from polyps first because if malignant want to use Cancer code if warranted. The colon has 4 areas in which dx block D12 can be used per where polyp removed while in intestine. If lab test states polyp is cancerous in which have the results use the proper dx code. Medicare usually use G code but check with payer in your region. Remember if there are benign neoplasms or ongoing problem list that dx first and the Z12.11 last. Patients who are coming for just regular colonoscopy as preventive due to age over 50 years or digestive problems or have had past family HO. Then use those Z codes last. You could use a digestive dx code first if related to their digestive or bleeding stomach or rectum , Etc. but doc should give you a problem on why checking for polyps. Modifier 33 or PT can be used if preventive for certain payers but in the patient's Medicare plan again I d check with the payer. I know in order to cover polyps and annual physical Medicare patients are required to do certain tests or preventive procedures in a certain time period to keep coverage. I think every 3 years if not had colon cancer.
The lab test maybe CPT 88305 will be coded next if polyps are found or bx taken from stomach or esophagus. Use a definitive dx (per patient s problem) and Z code last if want to get it paid. Modifier of XS be used if find 2 polyps or more differ areas of intestines or rectum . Insurance companies want definitive dx first, some Z dx codes are first listed which is fine to use but in this case use definitive dx per doc statements.

I hope helped you.
Lady T
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Thank you very much--totally appreciate it, Lady T!!

However, my follow up question is if the patient is getting a colonoscopy exam for the only purpose of colonoscopy screening (Z12.11) with no findings--nothing else documented, what is the appropriate coding guidelines (modifiers, dx code, CPT/HCPCS) to apply to avoid future denials?

We are receiving too many denials of Z12.11 codes for colonoscopy exams when there are no other findings nor other reasons but the Z12.11
(Encounter for screening for malignant neoplasm of colon)
If the patient comes in for a colon cancer screening, no other signs,symptoms, or other lower gi issues to work up, you would code Z12.11 as pdx with the findings as Sdx.
If there are signs/symptoms/etc, it is no longer a screening and would code to the reason for encounter/postoperative dx per guidelines.
There is a guideline that tells us screenings are only for seemingly well individuals. If there's another issue, it's no longer a screening
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As for cpt codes and modifiers, it depends on the insurer. Medicare uses the G codes for screenings without any intervention and they are based on provider documentation if the patient is high risk or not.
Medicare uses modifier PT for the other 4538- codes to note it was initially a screening turned diagnostic/therapeutic
Other insurers will use Modifier 33 for 45378 and for the other codes. This is because 45378 does not specifically state it is a screening code in the cpt description. The only way to tell it is a screening procedure is the modifier 33. I hope this helps!
Thanks so much--but I'm now confused again...the first reply I'm told to code findings first then Z12
11 code screening....but the 2nd reply tells me to code Z12.11 primary and the findings secondary if I'm reading my replies correctly...

Which sequence order do I code exactly??

Is Modifier PT ONLY appended when colorectal screening converts to a diagnostic or therapeutic service for Medicare patients i.e. findings during the colonoscopy screening? Or does modifier PT also applies to routine colonoscopy screenings with no findings as well?

If not, then which modifier is appended when it's ONLY a Z12.11 and nothing else? This question applies to commercial insurance AND Medicare. Thanks!!
Overall, I'm asking what modifiers do I use for CPT code 4537's when ONLY Z12.11 as routine screening is billed due to NO OTHER findings??

It seems like modifier 33 applies when there are other FINDINGS documented during routine screening.
And does same applies to modifier PT used for G-codes since it's HCPCS modifier when there are other FINDINGS documented during the colonoscopy screening exam???
Noridian Medicare tells us to code 45380, PT with Z codes prime and findings second. LINK the findings first and then the Z codes in box 24 E on the hcfa - so, 2,3,1. Hope that makes sense. :) I don't know about other Medicare carriers.
Commercial plans we use the 33 modifier even on the 45378 if it's a screening, just as a reminder. We use the Z codes prime then findings secondary.
It's my understanding that the purpose of the modifier is to tell the carrier that this started out as a screening/preventative service so don't apply it to the patient's deductible.
Hope that helps.
Agree with mconner. The trick is to read the CPT description. Since 45378 does not have the word "screening" modifier 33 will show that the 45378 was indeed a screening - with or without findings.
Totally appreciate your assistance--thank you very much!

I understand now that modifier 33 applies to commercial insurance and PT applies to Medicare.

Which Modifier 33 or PT applies to Medicaid?
I have a question on 33 and PT modifiers. Are you to use a 33 or PT modifier every time the patient comes in. Example. Pt is here for surveillance colonoscopy they have a personal history of polyps and they again find another polyp. For Medicare I would use K63.5 Z86.010 00811. For commercial I would use Z12.11 K63.5 Z86.010. Would I put 33s or PTs on again?

Thank you