Gastroenterology Coding Alert

Question: A patient with a history of adenomatous colon polyps came in for a screening colonoscopy. The report states that the gastroenterologist did not find any polyps during the colonoscopy. What diagnosis codes should I report for the procedure?

Georgia Subscriber

Answer: This is a unique situation that requires careful review of the provider’s documentation. The timing of the exam, intent of the colonoscopy, and the payer guidelines are all factors in your code selection.

The physician did not find any polyps during the exam, and if the patient isn’t exhibiting any signs or symptoms, the exam is a screening colonoscopy. Medicare allows screening colonoscopies once every two years for patients with a history of the disease. However, if the gastroenterologist performed the colonoscopy six months after the previous polypectomy to evaluate if the polyps were completely removed or if they recurred, then you’d assign Z09 (Encounter for follow-up examination after completed treatment for conditions other than malignant neoplasm) as the primary diagnosis code.

Based on the information you’ve provided, you’ll report the following ICD-10-CM codes:

• Z12.11 (Encounter for screening for malignant neoplasm of colon)
• Z86.0101 (Personal history of adenomatous and serrated colon polyps)

Code Z86.0101 was added to the ICD-10-CM code set on Oct. 1, 2024, but the code should not be used as a primary diagnosis code. According to the ICD-10-CM Official Guidelines, Section I.C.21.c.4, “Personal history codes may be used in conjunction with follow-up codes and family history codes may be used in conjunction with screening codes to explain the need for a test or procedure.”

The guidelines continue to state that the reason for the encounter “should be sequenced first and the appropriate personal and/or family history code(s) should be assigned as additional diagnos(es).”

At the same time, ICD-10-CM Official Guidelines, Section I.C.21.c.5, states “A screening code may be a first-listed code if the reason for the visit is specifically the screening exam.” In this case, the patient presented for a screening colonoscopy, which means Z12.11 is the primary diagnosis code. Additionally, “Encounter for screening colonoscopy not otherwise specified (NOS)” is listed as an additional diagnosis for Z12.11.

Of course, it is best to check with the patient’s payer to confirm what codes to assign and how to sequence the diagnosis codes in situations such as the one you’ve mentioned.

Mike Shaughnessy, BA, CPC, Development Editor, AAPC