Anthem Medicaid Medical Necessity Code List (DX codes)
Customize your policy alerts
Sign up for all Blue Cross Blue Shield - Maine policy alerts
Know when Blue Cross Blue Shield - Maine releases new policies or updates existing guidance.
Monitor payer policy activity
A listing of diagnosis (DX) codes that Anthem Medicaid designates for medical necessity purposes; intended for providers billing Anthem Medicaid in the covered jurisdiction.
No material clinical or coverage changes in this revision.
Coverage Criteria
Coverage criteria — DX code usage
Covered when the listed diagnosis code applies to the member encounter
Document provides codes only; specific service-level coverage rules are in other payer policies
This document is a flat listing of diagnosis codes used by Anthem Medicaid for medical necessity determinations. Coverage applies when the listed diagnosis code is the one that describes the member encounter and the payer requires a listed diagnosis for a given service. The list includes hematologic, pulmonary, and a large number of obstetric/perinatal codes commonly used to support maternity-related services.
No explicit exclusions are provided in this file; it functions solely as a compilation of ICD-9 diagnosis codes (including some V-codes) that Anthem Medicaid associates with medical necessity. Providers should consult applicable Anthem Medicaid service-level policies for any additional coverage limitations or prior authorization requirements.
Code Listings and Groups
| 042 | Human Immunodeficiency Virus [HIV] |
| 277.0x | Cystic Fibrosis |
| 282.xx | Hereditary Hemolytic Anemias |
| 283.xx | Acquired Hemolytic Anemias |
| 284.xx | Aplastic Anemias |
| 285.0 | Sideroblastic Anemia |
| 286.0-286.7 | Coagulation Defects |
| 287.1 | Qualitative Platelet Defects |
| 287.31 | Immune Thrombocytopenic Purpura (ITP) |
| 287.32 | Evans' syndrome |
| 555.00 | Regional enteritis of small intestine |
| 555.10 | Regional enteritis of large intestine |
| 555.20 | Regional enteritis of small intestine with large intestine |
| 555.90 | Regional enteritis of unspecified site |
| 556.90 | Unspecified ulcerative colitis |
| 558.10 | Gastroenteritis and colitis due to radiation |
| 558.20 | Toxic gastroenteritis and colitis |
| 578.90 | Hemorrhage of gastrointestinal tract, unspecified |
| 641.00 | Placenta previa without hemorrhage, unspecified as to episode of care |
| 641.01 | Placenta previa without hemorrhage, with delivery |
| 649.30 | Coagulation defects complicating pregnancy, childbirth, or the puerperium |
| 649.31 | Coagulation defects complicating pregnancy, childbirth, or the puerperium, delivered |
| 649.32 | Coagulation defects complicating pregnancy, childbirth, or the puerourium, delivered, with postpartum complic. |
| 649.40 | Epilepsy complicating pregnancy, childbirth, or the puerperium |
| 651.00 | Twin pregnancy, unspecified as to episode of care |
| 651.01 | Twin pregnancy, delivered |
| 655.01 | Central nervous system malformation in fetus, with delivery |
| 655.11 | Chromosomal abnormality in fetus, affecting management of mother, with delivery |
| 656.11 | Rhesus isoimmunization affecting management of mother, delivered |
| 657.00 | Polyhydramnios, unspecified as to episode of care |
Provider Actions and Billing Notes
Prior Authorization — see payer rules
Prior authorization requirements vary by Blue Cross Blue Shield - Maine plan. Providers must follow payer-specific rules and obtain any required prior authorization before rendering services when applicable.
- Check member's plan and BCBS Maine prior authorization policies before scheduling services.
- When in doubt, contact the payer's provider services or use the payer portal to verify prior authorization requirements.
Claim coding/documentation
Include the appropriate diagnosis code from the payer's medical necessity code list on the claim to support medical necessity. This document is a diagnostic code list; ensure the DX code on the claim matches the clinical indication and the codes listed by the payer.
- List the primary listed DX code that justifies the service.
- Include supporting documentation in the medical record and on request to substantiate medical necessity.
Potential denial risk from non-listed DX
Claims submitted with diagnosis codes not included on the payer's medical necessity list may be denied if the payer requires a listed DX for coverage. Providers should verify that the member's diagnosis appears on the payer's covered code list before billing.
- If the clinical diagnosis is not on the payer's list, obtain prior authorization or submit supporting clinical documentation to avoid denials.
- Monitor remittance advices and follow payer appeal procedures if a claim is denied for use of a non-listed diagnosis.
Background
Anthem Medicaid’s Medical Necessity Code List enumerates diagnosis codes in ICD-9 format (numeric codes and V-codes) used to document conditions that may justify medically necessary services. The list is heavily weighted toward obstetrics/gynecology and perinatal conditions but also contains hematologic and pulmonary diagnoses (for example, 042 – Human Immunodeficiency Virus [HIV] and multiple coagulation and anemia codes). Because this file contains codes only, it does not define service-specific clinical criteria; providers must pair the appropriate listed diagnosis code with the service on the claim to support medical necessity and follow any separate prior authorization rules from Anthem Medicaid.
Definitions
OpenPayer is powered by Trek Health's payer performance platform. Trek continuously ingests, validates, and normalizes Transparency in Coverage data alongside payer policies and other commercial payer data to create a structured payer intelligence foundation. OpenPayer uses this foundation to deliver personalized search results, dynamically generated policy pages, and tailored policy monitoring based on each user's payers, specialties, billing codes, and areas of interest. The same intelligence powers broader payer performance workflows, including reimbursement benchmarking, contract evaluation, payer negotiations, and financial decision-making.