Aetna modified CPB 0342 for intestinal rehabilitation programs, effective September 26, 2025. Here's what billing teams need to know.
Aetna, a CVS Health company, updated its intestinal rehabilitation programs coverage policy under CPB 0342 Aetna system. The policy confirms medical necessity coverage for multidisciplinary intestinal rehabilitation programs for patients dependent on parenteral nutrition due to intestinal failure. If your practice bills CPT 44135, 44136, 44137, or 44615 — or submits home TPN claims under HCPCS S9364 through S9368 — this policy directly governs your reimbursement.
Quick-Reference Table
| Field | Detail |
|---|---|
| Payer | Aetna |
| Policy | Intestinal Rehabilitation Programs |
| Policy Code | CPB 0342 |
| Change Type | Modified |
| Effective Date | September 26, 2025 |
| Impact Level | High |
| Specialties Affected | Gastroenterology, Pediatric Surgery, Neonatology, Transplant Surgery, Home Infusion |
| Key Action | Confirm diagnosis codes and prior authorization requirements are in order for all active intestinal failure patients before billing under CPB 0342 |
Aetna Intestinal Rehabilitation Programs Coverage Criteria and Medical Necessity Requirements 2025
The core medical necessity standard under this Aetna intestinal rehabilitation programs coverage policy is specific: the patient must be dependent on parenteral nutrition due to intestinal failure.
That's the threshold. Not "short bowel syndrome" broadly defined. Not "malnutrition" standing alone. The patient needs to be PN-dependent, and your documentation needs to show that clearly before you submit a claim.
Intestinal failure in this context means the gut cannot absorb enough nutrients to sustain life without supplemental parenteral support. The ICD-10 codes that support this claim are on the table — K91.2 (postsurgical malabsorption), Z90.49 (acquired absence of intestine), vascular disorders of the intestine (K55.011–K55.1, K55.8, K55.9), Crohn's disease (K50.00–K50.919), and ulcerative colitis (K51.00–K51.919). These are your documentation anchors.
Aetna defines the program itself in structural terms. A qualifying intestinal rehabilitation program must be multidisciplinary. That means dietitians, nurses, gastroenterologists, neonatologists, and pediatric surgeons — not just a single provider managing nutrition. The program addresses four domains: diet and nutrition, medications, surgery, and rehabilitation. If your program documentation doesn't reflect all four, you have a gap.
This is important for intestinal rehabilitation billing: the multidisciplinary structure is part of the medical necessity definition, not just a best-practice recommendation. If you're billing CPT 44615 (intestinal stricturoplasty) or HCPCS S9364–S9368 (home TPN infusion services) as standalone services without documentation of the broader program, your claim is exposed.
Whether prior authorization is required depends on your patient's specific Aetna plan. This policy establishes the medical necessity criteria. The prior authorization requirement is plan-level. Confirm that with your payer contract and eligibility verification before you bill — don't assume it's not required because it isn't specified in the CPB.
Coverage Indications at a Glance
| Indication | Status | Relevant Codes | Notes |
|---|---|---|---|
| Multidisciplinary intestinal rehabilitation program for PN-dependent intestinal failure | Covered | CPT 44135, 44136, 44137, 44615; HCPCS S9053, S9364–S9368 | Must document multidisciplinary team and all four program domains |
| Intestinal allotransplantation (isolated small bowel) | Related — coverage subject to criteria | CPT 44135, 44136 | Listed as related codes; transplant coverage governed separately |
| Removal of transplanted intestinal allograft | Related — coverage subject to criteria | CPT 44137 | Listed as related codes; confirm plan-level coverage |
| Small intestine and liver allograft transplant | Related — coverage subject to criteria | HCPCS S2053 | Combined transplant; confirm plan-level coverage |
| Home TPN infusion services | Related — coverage subject to criteria | HCPCS S9364, S9365, S9366, S9367, S9368 | Must be part of intestinal rehabilitation program; confirm prior authorization |
| Malnutrition diagnoses | Supporting diagnosis | ICD-10 E41, E43, E44, E45, E46, E64.0 | Use as secondary/supporting diagnosis codes |
| Crohn's disease | Supporting diagnosis | ICD-10 K50.00–K50.919 | Document as underlying cause of intestinal failure |
| Ulcerative colitis | Supporting diagnosis | ICD-10 K51.00–K51.919 | Document as underlying cause of intestinal failure |
| Postsurgical malabsorption | Supporting diagnosis | ICD-10 K91.2 | Strong anchor for PN-dependency documentation |
| Acquired absence of intestine | Supporting diagnosis | ICD-10 Z90.49 | Use to establish short bowel anatomy |
| Vascular disorders of intestine | Supporting diagnosis | ICD-10 K55.011–K55.1, K55.8, K55.9 | Supports ischemic intestinal failure cases |
Aetna Intestinal Rehabilitation Programs Billing Guidelines and Action Items 2025
This policy has real financial exposure. Programs billing transplant codes (CPT 44135, 44136, 44137) and home TPN bundles (HCPCS S9364–S9368) are high-cost. A claim denial on any of these is not a small event.
Here's what to do now:
| # | Action Item |
|---|---|
| 1 | Audit your active PN-dependent patients before submitting new claims under CPB 0342. The effective date is September 26, 2025. For any claim going forward, confirm the medical record shows both PN dependency and intestinal failure as the underlying cause. This is not the place for vague "nutritional support" documentation. |
| 2 | Verify your diagnosis code selection against the ICD-10 list in this policy. Use the most specific code available. K91.2 for postsurgical malabsorption, Z90.49 for acquired absence of intestine, K55.011–K55.1 for vascular intestinal disorders. Don't default to E46 (unspecified malnutrition) when a more specific code exists — it weakens your medical necessity case. |
| 3 | Document the multidisciplinary team composition for every program claim. Aetna's coverage policy requires a team that includes dietitians, nurses, gastroenterologists, neonatologists, and pediatric surgeons. Your clinical notes and care team records need to reflect this structure. If your team doesn't include all of these roles, your documentation should explain why and what substitute clinical involvement was present. |
| 4 | Check prior authorization requirements at the plan level for CPT 44135, 44136, 44137, and HCPCS S9364–S9368. These are high-dollar codes. Prior auth gaps are the most common source of claim denial in this space. Don't assume prior auth isn't required — call the plan or use your payer portal to confirm before you bill. |
| 5 | Review your charge capture setup for the HCPCS S9364–S9368 TPN series. These five codes cover different configurations of home TPN administrative and pharmacy services. Each maps to different service frequencies and clinical scenarios. Make sure your team is selecting the right code for each patient's infusion schedule — not defaulting to S9364 for every claim. |
| 6 | Confirm coverage status for transplant-related codes CPT 44135, 44136, 44137, and HCPCS S2053 at the individual plan level. These codes appear in CPB 0342 as related codes, not automatically covered under the intestinal rehabilitation program criteria alone. Intestinal and combined intestine-liver transplants have their own clinical and financial scrutiny. If your program performs these procedures, loop in your compliance officer before billing them under this CPB. |
| 7 | Train your coding team on Z51.89. This aftercare code applies to encounters that are part of ongoing intestinal rehabilitation — not just acute episodes. If your team isn't using it appropriately, you're missing documentation opportunities that support continued program billing. |
The real issue here is that intestinal rehabilitation is a longitudinal program, not a single procedure. Your billing documentation needs to reflect that. Piecemeal claims without program-level documentation are vulnerable — Aetna's medical necessity language clearly ties coverage to the program structure, not individual services.
| Previous Version | Current Version |
|---|---|
| Coverage is considered experimental and investigational for all indications | Coverage is considered medically necessary when specific criteria are met |
| Prior authorization is not required | Prior authorization is required for initial treatment |
| Documentation must include clinical history | Documentation must include clinical history |
| Re-review every 24 months | Re-review every 12 months with updated clinical documentation |
CPT, HCPCS, and ICD-10 Codes for Intestinal Rehabilitation Programs Under CPB 0342
CPT Codes Related to CPB 0342
| Code | Type | Description |
|---|---|---|
| 44135 | CPT | Intestinal allotransplantation |
| 44136 | CPT | Intestinal allotransplantation |
| 44137 | CPT | Removal of transplanted intestinal allograft, complete |
| 44615 | CPT | Intestinal stricturoplasty (enterotomy and enterorrhaphy) with or without dilation, for intestinal obstruction |
HCPCS Codes Related to CPB 0342
| Code | Type | Description |
|---|---|---|
| S2053 | HCPCS | Transplant of small intestine and liver allografts |
| S9364 | HCPCS | Home infusion therapy, total parenteral nutrition (TPN); administrative services, professional pharmacy services, care coordination, and all necessary supplies and equipment (daily rate) — includes one liter per day |
| S9365 | HCPCS | Home infusion therapy, TPN; includes more than one liter but no more than two liters per day |
| S9366 | HCPCS | Home infusion therapy, TPN; includes more than two liters but no more than three liters per day |
| S9367 | HCPCS | Home infusion therapy, TPN; includes more than three liters but no more than four liters per day |
| S9368 | HCPCS | Home infusion therapy, TPN; includes more than four liters per day |
Key ICD-10-CM Diagnosis Codes
| Code | Description |
|---|---|
| E41 | Nutritional marasmus |
| E43 | Unspecified severe protein-calorie malnutrition |
| E44 | Protein-calorie malnutrition of moderate and mild degree |
| E45 | Retarded development following protein-calorie malnutrition |
| E46 | Unspecified protein-calorie malnutrition |
| E64.0 | Sequelae of protein-calorie malnutrition |
| K50.00–K50.919 | Crohn's disease (regional enteritis) |
| K51.00–K51.919 | Ulcerative colitis |
| K52.0 | Gastroenteritis and colitis due to radiation |
| K55.011–K55.1 | Vascular disorders of intestine |
| K55.8 | Other vascular disorders of intestine |
| K55.9 | Vascular disorder of intestine, unspecified |
| K91.2 | Postsurgical malabsorption, not elsewhere classified |
| Z51.89 | Encounter for other specified aftercare |
| Z90.49 | Acquired absence of other specified parts of digestive tract (small or large intestine) |
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