Q43.2
BillableOther congenital functional disorders of colon
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is Q43.2 an HCC code?
Yes. Q43.2 maps to Intestinal Obstruction/Perforation under the CMS-HCC V28 risk adjustment model.
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for Q43.2
For Q43.2 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed Q43.2 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
Q43.2 is the ICD-10-CM diagnosis code for other congenital functional disorders of colon. A birth defect affecting how the colon functions normally, such as abnormal muscle contractions or nerve function, without structural malformation. Q43.2 sits in the ICD-10-CM chapter for congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (q00-qa0), within the section covering other congenital malformations of the digestive system (q38-q45).
Under the CMS-HCC V28 risk adjustment model, Q43.2 maps to Intestinal Obstruction/Perforation (HCC 78) with a community, non-dual, aged base RAF weight of 0.000. Q43.2 was not retained as a payment HCC under the older V24 model, so V28 introduced or recategorized it during the 2024–2026 phase-in. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
This code is used when there is functional impairment of the colon without anatomical absence or obstruction. Because Q43.2 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for Q43.2 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This code is used when there is functional impairment of the colon without anatomical absence or obstruction
- •Document the specific functional disorder if known to support medical necessity
Clinical Significance
This code captures other congenital functional disorders of the colon that don't fit specific categories like Hirschsprung's disease, representing conditions requiring specialized gastroenterology management. These disorders can significantly impact quality of life and may require complex treatment approaches including dietary modifications and medications.
Documentation Requirements
- ✓Specific type of functional disorder documented
- ✓Evidence of congenital rather than acquired nature
- ✓Functional assessment of colonic motility or nerve function
- ✓Associated symptoms and their severity
- ✓Response to treatments attempted
- ✓Exclusion of Hirschsprung's disease or structural abnormalities
- ✓Any genetic or family history information