CPT code 76776 – Transplanted kidney ultrasound

Key takeaways

CPT Code 76776 covers ultrasound of a transplanted kidney (renal allograft) only, not native kidneys.

Duplex Doppler is part of 76776, so never add 93976 or 93975 for it. A gray-scale-only transplant scan is reported as 76775.

ICD-10 code Z94.0 (kidney transplant status) is the usual supporting diagnosis for routine post-transplant scans. When a T86.1x complication is the indication, report that code instead.

Global billing, modifier 26, and modifier TC each apply in different facility scenarios, and mixing them causes duplicate billing denials.

Pabau’s claims management software sends claims through Claim.MD and warns when a prior authorization code is missing.

CPT Code 76776: Quick reference

CPT Code 76776 reports a real-time ultrasound of a transplanted kidney with duplex Doppler and image documentation, billed as one service. The Doppler is never billed again as 93976 or 93975, and a transplant scan without Doppler is reported as 76775.

The table below sums up the billing facts at a glance. Verify payment amounts against the current Medicare Physician Fee Schedule, since rates change every year and vary by locality.

What CPT Code 76776 covers: Official descriptor and procedure scope

The American Medical Association’s CPT code set defines 76776 as: Ultrasound, transplanted kidney, real time and duplex Doppler with image documentation. Every word carries billing weight.

• Ultrasound: Gray-scale (B-mode) sonographic imaging of the allograft is the first half of the service.
• Duplex Doppler: Doppler evaluation of the transplant vessels is built into 76776. Do not report 93976 or 93975 for that same Doppler, and check the current NCCI edits before adding any vascular code. A transplanted kidney scanned without duplex Doppler is reported as 76775 (limited retroperitoneal ultrasound), not 76776 with modifier 52.
• Transplanted kidney: The code is restricted to a renal allograft, meaning a kidney placed surgically from a donor. It never applies to native (original) kidneys in situ.
• Real time: The physician or qualified technician performs the scan in real time, not from a stored image review.
• With image documentation: Representative images must be captured and stored as part of the permanent record. A verbal-only or undocumented scan does not meet this requirement.

The clinical scenarios where 76776 is appropriate include routine post-transplant surveillance, evaluation of rising creatinine, suspected rejection, perinephric fluid collection, ureteral obstruction, and vascular complications. The code is used in both inpatient and outpatient settings and is billed by radiologists and nephrologists depending on who performs and interprets the study.

How the procedure is performed and what must be documented

Documentation drives reimbursement for 76776. Claims that lack any of the elements below are vulnerable to medical necessity denials, even when the scan itself was clinically appropriate.

1. Ordering provider details: The physician order must name the clinical indication (e.g., elevated creatinine post-transplant, suspected rejection). Without a documented order, payers may flag the claim as self-referred.
2. Gray-scale imaging of the allograft: Document longitudinal and transverse views of the transplanted kidney. Record dimensions in at least two planes. Note echogenicity, cortical thickness, and any masses or fluid collections.
3. Duplex Doppler of the transplant vessels: Document spectral and color Doppler of the main renal artery, the renal vein and the intrarenal arteries. Record peak systolic velocities and resistive indices. Without this, the study does not meet 76776 and is reported as 76775.
4. Evaluation of the collecting system and ureter: Assess for hydronephrosis, ureteral dilation, or perinephric collections. Document presence or absence of each finding.
5. Representative images stored: PACS or equivalent must retain the images. The report should reference the number of images acquired and the planes documented.
6. Final interpreted report: A signed interpretation by the interpreting physician must be on file before the claim is submitted. Preliminary reads that are never finalized create audit exposure.

CPT 76776 vs 76770 vs 76775: Which code applies?

The three retroperitoneal ultrasound codes are the most common source of coding errors in this category. Use the table below to select the right code before submitting.

The key rule: 76776 is correct only when the patient has a transplanted kidney and that allograft is imaged with duplex Doppler. A gray-scale-only scan of the allograft is reported as 76775. Two questions settle the code, and the panel below walks through both.

When the same patient also has native kidneys evaluated in the same session, that evaluation needs a separate code, 76770 or 76775. NCCI edits may bundle 76776 with either code on the same date for the same patient. Verify the current National Correct Coding Initiative table before billing both together.

Related codes that are commonly billed with or instead of 76776

Three codes come up most often next to 76776. One is billed with it, one is billed instead of it, and one is a common duplicate that should not be added.

Because duplex Doppler is part of 76776, a transplant ultrasound report that covers gray-scale and Doppler findings supports one code, not two. Adding 93976 for the same Doppler is a duplicate charge, however the report is written. If the Doppler was not performed, the study is 76775, so the report must state clearly whether Doppler was done.

ICD-10 diagnosis codes that support 76776 medical necessity

Pairing CPT Code 76776 with the correct ICD-10-CM diagnosis codes is not optional. Many Medicare Administrative Contractors and commercial payers list specific covered diagnoses in their Local Coverage Determinations. Z94.0 is for routine surveillance and transplant status. When a complication is the indication, report a T86.1x code such as T86.11 for rejection instead of Z94.0, not alongside it.

Payer LCD policies differ on which ICD-10 codes they accept as covered indications. Always review the applicable MAC’s LCD for the specific payer before assuming Z94.0 alone is sufficient for every commercial plan.

Modifier usage for CPT Code 76776: 26, TC, and global billing

Which modifier to append to 76776 depends entirely on who owns the equipment and who performs the interpretation. Getting it wrong gets a transplant ultrasound claim denied or paid at the wrong rate.

A common error: A hospital-employed radiologist submits 76776 globally (no modifier) while the facility also bills 76776-TC. This creates duplicate billing. Each party must bill only their respective component. CMS guidance on the professional/technical component split is clear, and payers will pay only one side per entity.

Medicare and payer reimbursement for CPT Code 76776

Medicare payment for 76776 is calculated from the CMS Medicare Physician Fee Schedule using relative value units (RVUs), adjusted by geographic practice cost indices. The global code is priced only in the non-facility setting. In a facility, the physician bills modifier 26 and the facility bills TC separately.

The table below shows the 2026 RVUs for each billing option, from the CMS 2026 PFS RVU file. Verify the current-year payment amount for your locality using the FastRVU 2026 lookup tool or the CMS MPFS search.

Source: CMS 2026 PFS RVU file (RVU26B). The global code carries no facility price.

Prior authorization requirements

Medicare does not typically require prior authorization for 76776, but Medicaid and commercial plans vary significantly. Some commercial payers, particularly managed care organizations, require prior authorization for outpatient imaging studies including transplant ultrasound.

Requirements differ by payer, plan, and state, so check the specific plan’s authorization lookup tool before scheduling the study. When prior auth is required, include the authorization number on the claim form to prevent CO-197 denials (precertification/authorization absent).

Pabau is the practice management platform we build. Practices using it can track prior authorization codes, dates and sessions on the case, and run eligibility checks. Claims go to payers through its Claim.MD clearinghouse integration.

Common reasons CPT Code 76776 claims are denied and how to fix them

Practices that bill transplant imaging should check for these patterns before submission. Claims management software can help with eligibility and authorization checks. The table lists the most common denial scenarios and their corrective actions.

A structured denial management workflow that categorizes 76776 rejections by denial code makes patterns visible. If CO-4 appears repeatedly, the problem is usually at the coder or template level. If CO-197 appears repeatedly, the problem is in the scheduling and authorization workflow. The denial code reference lists each CARC and remark code with its fix.

Documentation checklist for a clean 76776 claim

Run through this checklist before submitting any 76776 claim, and use it as a training tool for coding and billing staff.

• Correct code confirmed: Patient has a documented kidney transplant. 76776 is appropriate. If the patient has only native kidneys, switch to 76770 or 76775.
• Supporting diagnosis linked: Z94.0 (kidney transplant status) is attached for routine surveillance. If a specific complication is the indication, the T86.1x complication code is attached instead of Z94.0, not with it.
• Physician order documented: Written or electronic order on file naming the clinical indication (e.g., elevated serum creatinine, suspected rejection, post-transplant surveillance). Order references the allograft explicitly.
• Real-time imaging performed: Documentation confirms the scan was performed in real time, not from stored images.
• Duplex Doppler documented: The report describes the Doppler of the main renal artery, renal vein and intrarenal arteries, with velocities and resistive indices. If no Doppler was done, the code is 76775, not 76776.
• Representative images stored in PACS: Report references the number of images and planes documented. Images are retrievable in the EHR or PACS for the duration required by your payer contract.
• Final signed interpretation on file: Interpreting physician has signed and finalized the report before the claim is submitted. Preliminary reads are not sufficient.
• Correct modifier appended: Global (none), modifier 26, or TC, confirmed by who owns the equipment and who interprets.
• Prior authorization number included: If the payer or plan requires prior auth, the authorization number is on the claim form. A missing authorization number is a common cause of CO-197.
• No separate Doppler code: 93976 and 93975 are not on the claim for the transplant Doppler, which 76776 already includes.
• NCCI edit check completed: If 76942 or another code is billed on the same date, the current NCCI edits confirm the pair is billable together.
• No duplicate submission: If the facility is billing 76776-TC, the physician is billing 76776-26, not 76776 globally.

How claims management software helps reduce 76776 denials

Most 76776 denials start at charge entry. A coder picks 76776 for a gray-scale-only scan, adds 93976 for Doppler that the code already covers, or leaves Z94.0 off the claim. Each mistake surfaces weeks later as a rejection that someone has to work by hand.

Practices using Pabau can run eligibility checks, send claims through Claim.MD, and see a warning when a prior authorization code is missing. That warning helps head off CO-197 authorization denials.

Build the coding checklist above into your clean claim workflow so each claim is checked before it goes out.

Reduce 76776 denials with smarter billing workflows

Pabau connects US practices to Claim.MD for electronic claim submission, eligibility checks and ERA remittances. Track authorization codes, dates and sessions on the case, with a warning when one is missing.

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Conclusion

CPT Code 76776 pays for one complete service: a real-time scan of the transplanted kidney with duplex Doppler and stored images. Treat it as that single unit. The Doppler is never billed again as 93976, and a scan without Doppler belongs under 76775.

Get the code right first, then protect it with the right diagnosis and the correct modifier for your facility setup. That means Z94.0 for routine scans, or the T86.1x code when a complication is the indication. That sequence prevents most of the denials this code attracts. Set it up once in your medical billing workflow and every transplant scan follows it. To see how Pabau handles claims and prior authorization tracking for specialty practices, book a demo.

Continue your research

Need to track claim denials by code? Denial management in healthcare covers how to build a denial tracking workflow that spots patterns before they become write-offs.

Looking for the full denial code reference? Denial codes in medical billing lists CARC and remark codes with their corrective actions for common claim rejections.

Want to streamline the full revenue cycle? What is revenue cycle management explains the end-to-end process from eligibility check through final payment posting.

Scanned the allograft without Doppler? CPT code 76775 covers the limited retroperitoneal ultrasound that applies instead.

Is rejection the indication? ICD-10 code T86.11 explains how to code kidney transplant rejection, reported instead of Z94.0 when rejection is the indication.

Frequently asked questions