Appeal — TEST-CLAIM-00073

Date: [Letter Date]

Via: [Submission Method]

Synthetic UHC
Appeals and Grievances Department
[Payer Address]

RE: Formal Appeal of Claim Denial — CO-18 Duplicate Claim
Claim Number: TEST-CLAIM-00073
Internal Claim ID: e48f78c7-c080-492b-8414-3af82d96f3e0
Payer: Synthetic UHC
Date of Service: February 23, 2026
Denial Date: March 20, 2026
Denied Amount: $2,872.89
Appeal Deadline: June 18, 2026

Dear Appeals and Grievances Department,

This letter constitutes a formal appeal on behalf of [Hospital/Facility Name] contesting the denial of Claim TEST-CLAIM-00073, issued by Synthetic UHC on March 20, 2026. The claim was denied under reason code CO-18 (Exact Duplicate Claim/Service), resulting in a denied amount of $2,872.89. We respectfully assert that this denial is not substantiated and request that Synthetic UHC overturn the determination, reprocess the claim, and issue payment for the denied amount.

I. BACKGROUND AND NATURE OF THE DENIAL

Claim TEST-CLAIM-00073 was submitted for services rendered on February 23, 2026, and reflects the following billable procedures and diagnoses:

  - CPT 30631 — Nasal Endoscopy with Surgical Service
  - CPT 58503 — Hysteroscopy with Polypectomy
  - ICD-10 N39.99 — Unspecified Urinary Tract Disorder
  - ICD-10 F32.76 — Recurrent Depressive Disorder

The total billed amount for the claim is $4,837.47, of which $2,872.89 was denied under the assertion that the claim constitutes an exact duplicate of a previously adjudicated service.

We dispute this determination. A CO-18 denial is only appropriate where an identical claim — reflecting the same patient, the same date of service, and the same procedures — has been previously adjudicated and paid. The documentation enclosed with this appeal demonstrates that this standard has not been met.

II. BASIS FOR APPEAL

A. No Prior Payment Has Been Confirmed for This Exact Service

A CO-18 denial presupposes that a prior, identical claim was adjudicated and payment was issued. A review of the enclosed Explanation of Benefits (EOB) and payment history documentation reveals no confirmed prior payment for CPT 30631 and CPT 58503 as billed for the February 23, 2026 date of service. In the absence of confirmed prior payment, the predicate condition for a CO-18 duplicate denial is not satisfied, and the denial must be overturned.

B. The Procedures Billed Are Clinically and Procedurally Distinct

CPT 30631 (nasal endoscopy) and CPT 58503 (hysteroscopy with polypectomy) represent two separate, anatomically distinct surgical procedures. The enclosed operative report and procedure notes confirm that both procedures were performed and documented as discrete clinical services on February 23, 2026. These procedures are not duplicative of one another, nor is either procedure duplicative of any previously adjudicated claim, as supported by the enclosed claim submission records and communication log.

C. Submission Records Demonstrate No True Duplicate

The enclosed claim submission records — including original submission documentation with timestamps — demonstrate that any secondary submission, if made, differed in material claim-level detail from the original, or that no prior adjudicated version of this exact claim exists in Synthetic UHC's records. Pursuant to Synthetic UHC's duplicate claim submission rule, a claim may only be denied as a duplicate when all identifying elements are identical to a previously paid claim. Where discrepancies exist between submissions, the appropriate course of action is reprocessing with a request for clarification, not denial.

D. Payer Policy Requires Affirmative Demonstration of Prior Payment

Under Synthetic UHC's applicable duplicate claim submission policy, the payer bears the burden of demonstrating that an identical claim was previously adjudicated and paid before issuing a CO-18 denial. As set forth above and supported by the enclosed documentation, no such prior adjudication and payment has been established for this specific combination of patient, date of service, and procedure codes. Accordingly, the denial is inconsistent with the payer's own policy standards.

III. SUPPORTING DOCUMENTATION ENCLOSED

The following documents are enclosed in support of this appeal:

  1. Claim submission records (original and any secondary submission) with timestamps
  2. Patient medical record with service date documentation confirming February 23, 2026
  3. Operative report and procedure notes for CPT 30631 and CPT 58503
  4. Explanation of Benefits (EOB) and payment history demonstrating absence of prior payment for this exact service
  5. Communication log between hospital billing department and Synthetic UHC regarding claim submission
  6. Corrected or amended claim submission, if applicable

IV. REQUESTED REMEDY

Based on the foregoing, [Hospital/Facility Name] respectfully requests that Synthetic UHC:

  1. Overturn the CO-18 denial issued on March 20, 2026, for Claim TEST-CLAIM-00073;
  2. Reprocess the claim in accordance with the member's applicable plan benefits; and
  3. Issue payment of the denied amount of $2,872.89 to [Hospital/Facility Name].

We request that this appeal be resolved prior to the appeal deadline of June 18, 2026. If additional information is required to complete the review, please contact the undersigned at the information provided below at your earliest convenience.

Thank you for your prompt attention to this matter. We trust that upon review of the enclosed documentation, Synthetic UHC will agree that the CO-18 denial is not supported by the evidence and that payment of the denied amount is warranted.

Respectfully submitted,

[Authorized Signatory Name]
[Title]
[Hospital/Facility Name]
[Address]
[Phone Number]
[Email Address]
[Date]