🩺 CPT 50575 — Renal Endoscopy Through Nephrotomy or Pyelotomy; With Endopyelotomy
Quick Reference
wRVU: 13.61 | Global Period: 090 | Assistant Payable: No (statutory restriction) | Bilateral Indicator: 1 Rule: CPT 50575 carries a 90-day global period and a Non-Facility “NA” pricing status¹ — meaning this procedure is not separately valued in the non-facility (office) setting because it is inherently a hospital/ASC-based intervention. The multiple-endoscopy indicator of “3” means special payment rules apply: when billed with other codes in the 50570–50580 family at the same session, the value of base code 50570 is subtracted from the second/subsequent procedure. Assistant-at-surgery payment is statutorily restricted for this code (indicator 1), meaning Medicare will not reimburse an assistant surgeon regardless of documentation submitted.
📋 Clinical Description
CPT 50575 describes an endoscopic treatment of a ureteropelvic junction (UPJ) obstruction performed via an existing or newly created nephrotomy or pyelotomy tract. The descriptor bundles cystoscopy, ureteroscopy, dilation of the ureter and UPJ, incision of the stenotic UPJ segment, and fluoroscopic/endoscopic imaging into a single global code, distinguishing it from the more limited services described by base code 50570 (diagnostic renal endoscopy only) and 50572 (renal endoscopy with ureteral catheterization and/or dilation, without incision of the UPJ itself).
Endopyelotomy is most often performed for a stenotic or scarred UPJ that has failed a prior pyeloplasty, or as a primary treatment in patients who are poor candidates for open/laparoscopic/robotic reconstruction. The procedure concludes with placement of an internalized ureteral stent to splint the incised segment during healing, distinguishing it functionally from 50576 (renal endoscopy with fulguration and/or incision with or without biopsy, used for urothelial lesions rather than UPJ strictures).
This procedure may be performed in the following clinical contexts:
- Primary UPJ obstruction refractory to observation — used when a congenital or acquired UPJ stricture has caused progressive hydronephrosis and the patient is not an ideal candidate for pyeloplasty.
- Recurrent/failed pyeloplasty — endopyelotomy is a common salvage option after open, laparoscopic, or robotic pyeloplasty failure, since re-operative reconstruction carries higher morbidity.
- Crossing-vessel-negative anatomy — endopyelotomy is favored when preoperative imaging excludes a lower-pole crossing vessel, since incision across an unrecognized vessel risks hemorrhage.
- Combined stone/UPJ disease — frequently performed in the same session as percutaneous stone extraction when a calculus and a UPJ stricture coexist, in which case NCCI and multiple-procedure rules become highly relevant.
🔬 Anatomical & Procedural Considerations
| Variant | Mechanism | Key Notes |
|---|---|---|
| Percutaneous Antegrade Endopyelotomy | A nephrostomy tract is established or an existing tract is used to pass a rigid or flexible nephroscope directly into the renal pelvis, from which the UPJ stricture is incised full-thickness (typically posterolaterally) using a cold knife, hot knife, or laser fiber under direct and fluoroscopic visualization. | This is the classic approach captured by the 50575 descriptor’s “nephrotomy or pyelotomy” language; it allows the largest working channel and the most precise stricture incision but carries the added morbidity of a percutaneous renal access tract. |
| Retrograde (Ureteroscopic) Endopyelotomy | A flexible or rigid ureteroscope is passed cystoscopically and retrograde up the ureter to the UPJ, where the stricture is incised endoluminally, often with a holmium or thulium laser, without a percutaneous renal puncture. | Although clinically similar in intent, this transurethral-only approach without any nephrotomy/pyelotomy access is more accurately reported with the cystourethroscopy-with-ureteroscopy family (e.g., 52344/52345) rather than 50575, which specifically requires a renal/pyelotomy access point — a frequent source of code selection confusion. |
| Endopyelotomy with Concurrent Stone Extraction | Performed identically to the percutaneous antegrade technique above, but a coexisting renal or proximal ureteral calculus is fragmented and extracted through the same tract before or after the UPJ incision. | Because both the stone removal and the endopyelotomy occur through the same access, correct sequencing and NCCI bundling review are essential; the endopyelotomy code (50575) generally represents the more extensive/comprehensive service in this pairing. |
Clinical Pearl
The single most common denial trigger for CPT 50575 is code selection error — many practices default to 50575 for any endoscopic UPJ incision, even when the approach was purely retrograde/ureteroscopic with no nephrotomy or pyelotomy access created. Confirm the operative note explicitly documents percutaneous or open renal-pelvis access before assigning 50575; a retrograde-only ureteroscopic incision belongs in the 52344/52345 cystourethroscopy family instead.
✅ Procedure Includes
- Cystoscopy performed to gain initial access to the urinary tract before advancing to the renal pelvis.
- Ureteroscopy performed as part of the access pathway to the UPJ and renal pelvis.
- Dilation of the ureter and the ureteropelvic junction to accommodate endoscopic instrumentation.
- Full-thickness incision of the stenotic ureteropelvic junction segment.
- Fluoroscopic and/or endoscopic imaging used to guide instrument passage and confirm adequate incision.
- Insertion of an internalized ureteral (endopyelotomy) stent to splint the incised UPJ during healing.
❌ Excludes / Do Not Report Together
| Code | Description | Relationship |
|---|---|---|
| 50570 | Renal endoscopy through nephrotomy or pyelotomy, diagnostic (no incision/biopsy/removal) | 50570 is the endoscopic base code for the entire 50570–50580 family; it is never separately reported with 50575 when performed at the same encounter through the same access, since the diagnostic inspection is inherent to the more extensive endopyelotomy service. |
| 50572 | Renal endoscopy with ureteral catheterization, with or without dilation of ureter | Represents a lesser degree of intervention (catheterization/dilation without UPJ incision); reporting both 50572 and 50575 for the same UPJ segment at the same session is not appropriate, as UPJ dilation is already bundled into 50575. |
| 52344, 52345 | Cystourethroscopy with ureteroscopy, with treatment of ureteral or UPJ stricture (retrograde approach) | These describe the retrograde-only endoscopic correlate of UPJ incision without a nephrotomy/pyelotomy tract; 50575 and 52344/52345 should not both be billed for a single UPJ incision performed through a single approach — only one code should reflect the actual access and technique used. |
| 50693-50695 | Percutaneous ureteral stent placement (with nephrostogram/ureterogram) | Historically bundled as a Column 1/Column 2 NCCI edit with 50575 when the stent placed is the same one required to splint the endopyelotomy; verify current-year NCCI PTP edit status and modifier indicator before reporting both. |
Bundling Alert
CPT 50575 carries a 90-day global surgical period, so any postoperative stent removal, cystoscopy, or imaging performed within that window by the same surgeon or group is generally not separately payable absent an unrelated diagnosis and appropriate modifier (e.g., -79). Because the multiple-endoscopy indicator is “3,” reporting 50575 with any other code from the 50570–50593 renal/ureteral endoscopy family at the same session triggers a deduction of the base-code (50570) value from the lesser procedure rather than a flat 50% multiple-procedure reduction — auditors frequently flag claims where this special calculation was not applied correctly. NCCI edits involving the concurrent stent-placement codes (50693 series) should be checked against the current-quarter edit file, since the endopyelotomy code already includes stent insertion as an integral component of the global service.
🌳 Code Tree — Surgery: Urinary System — Kidney
CPT 50010-50593 Surgery: Urinary System — Kidney
│
├── 50551-50561 Renal Endoscopy Through Established Nephrostomy or Pyelostomy
│ ├── 50551 Renal endoscopy through established nephrostomy or pyelostomy, diagnostic
│ └── 50561 Renal endoscopy through established nephrostomy or pyelostomy; with removal of foreign body or calculus
│
├── 50570-50580 Renal Endoscopy Through Nephrotomy or Pyelotomy
│ ├── 50572 Renal endoscopy through nephrotomy or pyelotomy; with ureteral catheterization, with or without dilation of ureter (Global: 090)
│ ├── 50574 Renal endoscopy through nephrotomy or pyelotomy; with biopsy (Global: 090)
│ ├── ▶▶ 50575 ◀◀ Renal endoscopy through nephrotomy or pyelotomy; with endopyelotomy (includes cystoscopy, ureteroscopy, dilation of ureter and ureteropelvic junction, incision of the ureteropelvic junction and imaging) ← YOU ARE HERE (Global: 090)
│ ├── 50576 Renal endoscopy through nephrotomy or pyelotomy; with fulguration and/or incision, with or without biopsy (Global: 090)
│ └── 50580 Renal endoscopy through nephrotomy or pyelotomy; with removal of foreign body or calculus (Global: 090)
│
└── 50590-50593 Lithotripsy Procedures on the Kidney
├── 50590 Lithotripsy, extracorporeal shock wave
└── 50593 Ablation, renal tumor(s), unilateral, cryotherapy💰 RVU & Reimbursement Profile
| Component | Value |
|---|---|
| Work RVU | 13.61 — per PPRRVU2026_Jan_QPP.xlsx (CY2026 January release)² |
| Global Period | 090 — major surgical procedure |
| Bilateral Indicator | 1 — 150% payment adjustment applies for bilateral procedures; report with modifier -50 when performed on both kidneys/UPJs at the same session |
| Assistant Surgeon | 1 — statutory payment restriction; Medicare will not reimburse an assistant at surgery for this code under any circumstances |
| Co‑Surgeon | 0 — co-surgeons are not permitted for this procedure |
| Team Surgery | 0 — team surgery concept does not apply |
| PC/TC Split | 0 — physician service code; no professional/technical component split applies (this is a global surgical service, not a diagnostic test) |
| Modifier -51 Exempt | No — subject to the special multiple-endoscopy base-code deduction (Mult Proc indicator 3) rather than a standard -51 reduction |
| Anesthesia | Not applicable — anesthesia is reported separately by the anesthesia provider using the CPT code(s) corresponding to the anatomic area (e.g., renal/ureteral anesthesia code range), per ANES2026 base unit values |
Bilateral Billing Rules
Although simultaneous bilateral UPJ endopyelotomy is clinically uncommon, the bilateral indicator of “1” means that if it is performed, modifier -50 should be appended and payment calculated at 150% of the single-code allowable rather than reporting the code twice with -RT/-LT. Verify the specific MAC’s claims-processing preference (single line with -50 vs. two lines with -RT/-LT and -50 on the second line) before submission, since processing conventions vary by contractor.
🏷️ Modifier Reference
| Modifier | Name | When to Apply |
|---|---|---|
| -RT | Right Side | Append when the endopyelotomy is performed on the right kidney/UPJ only, to establish laterality for a paired organ. |
| -LT | Left Side | Append when the endopyelotomy is performed on the left kidney/UPJ only. |
| -50 | Bilateral | Append for a true bilateral endopyelotomy performed at the same operative session, consistent with the bilateral indicator of “1.” |
| -51 | Multiple Procedures | May apply when 50575 is billed with an unrelated procedure outside the 50570–50593 endoscopy family; not the correct modifier for stacking within that same family, where the base-code deduction rule governs instead. |
| -59 | Distinct Service | Used to indicate that a same-session procedure (e.g., stone extraction or biopsy) was performed at a separate, distinct site or through a separate access from the endopyelotomy, supporting an NCCI edit override when clinically justified. |
| -52 | Reduced Services | Applies if the endopyelotomy was planned but only partially completed (e.g., incision made but stent could not be advanced) without meeting the threshold for a discontinued-procedure modifier. |
| -53 | Discontinued | Applies if the procedure was terminated after anesthesia induction due to patient instability or unexpected anatomic findings before the endopyelotomy could be completed. |
| -76 | Repeat Procedure | Applies if a repeat endopyelotomy is required by the same physician due to re-stricture or stent-related complication within the global period. |
| -78 | Return to OR | Applies for an unplanned return to the operating/procedure room during the 90-day global period for a complication directly related to the original endopyelotomy (e.g., bleeding, stent migration requiring re-intervention). |
🩺 Common ICD‑10‑CM Pairings
Primary Diagnosis Group
| ICD‑10 | Description | HCC? | Notes |
|---|---|---|---|
| N13.0 | Hydronephrosis with ureteropelvic junction obstruction | ❌ No | This is the classic and most frequently paired code for acquired UPJ obstruction treated with endopyelotomy; verify against the current CMS-HCC V28 model file, as this flag is based on general risk-adjustment category patterns rather than a live model lookup. |
| N13.2 | Hydronephrosis with renal and ureteral calculous obstruction | ❌ No | Appropriate when a coexisting calculus is the driver of the UPJ obstruction and hydronephrosis, particularly relevant when 50575 is billed alongside stone-extraction codes. |
| Q62.11 | Congenital occlusion of ureteropelvic junction | ❌ No | Used when the UPJ obstruction is documented as congenital in origin rather than acquired/scarred (e.g., failed prior pyeloplasty for congenital UPJ disease in an adult). |
| N13.1 | Hydronephrosis with ureteral stricture, not elsewhere classified | ❌ No | Appropriate when the stricture responsible for the hydronephrosis is not specifically documented as UPJ-level, but the operative note confirms the incision was performed at the ureteropelvic junction. |
Secondary Group
| ICD‑10 | Description | HCC? | Notes |
|---|---|---|---|
| N20.0 | Calculus of kidney | ❌ No | Report as a secondary diagnosis when a renal calculus coexists with the UPJ obstruction and is addressed in the same operative session. |
| N13.30 | Unspecified hydronephrosis | ❌ No | Use only when imaging/operative documentation does not further specify the level or etiology of obstruction; specificity to N13.0/N13.1/N13.2 should always be sought first. |
Etiology / Complication
| ICD‑10 | Description | HCC? | Notes |
|---|---|---|---|
| N11.1 | Chronic obstructive pyelonephritis | ❌ No | Report when chronic infection has developed secondary to the long-standing UPJ obstruction; do not report concurrently with N13.0 for the same encounter without physician documentation clarifying both conditions are separately present, since N13.0 carries an Excludes2 note for obstructive pyelonephritis. |
| N39.0 | Urinary tract infection, site not specified | ❌ No | Appropriate as an additional code when an acute, non-chronic UTI is documented as a comorbid condition at the time of the procedure. |
Coding Specificity Reminder
N13 (Obstructive and reflux uropathy) is a non-billable parent category — always code to the fourth or fifth character (N13.0, N13.1, N13.2, N13.30, etc.) reflecting laterality-free but etiology-specific documentation. Confirm whether the operative note supports a congenital (Q62.11) versus acquired (N13.0) etiology, since the two are mutually exclusive from a coding-instruction standpoint and drive different code selection despite an identical procedure.
🏥 MS‑DRG Considerations
When CPT 50575 (mapped to ICD-10-PCS Dilation of the kidney pelvis or ureter) is the principal procedure on an inpatient claim for UPJ obstruction, it typically groups to MS-DRG 673 (Other Kidney and Urinary Tract Procedures with MCC), 674 (with CC), or 675 (without CC/MCC), depending on documented complications or comorbidities captured elsewhere on the claim. No CMS National Coverage Determination (NCD) specific to endopyelotomy was identified, which is expected — NCDs predominantly govern diagnostic tests, DME, and preventive services rather than surgical procedures of this type. No MAC-specific Local Coverage Determination (LCD) explicitly naming CPT 50575 was located in this review; however, LCD applicability should always be confirmed directly against your jurisdiction’s Medicare Administrative Contractor (e.g., Novitas, Noridian, CGS) via the CMS Medicare Coverage Database, and reimbursement amounts should be cross-checked against the live CMS Physician Fee Schedule (PFS) Lookup Tool, since values in this note reflect the January 2026 release file only and are subject to mid-year correction notices.
🔧 ICD‑10‑PCS Equivalents
| PCS Code | Full Description | Modality |
|---|---|---|
| 0T734DZ | Dilation of Right Kidney Pelvis with Intraluminal Device, Percutaneous Endoscopic Approach | Percutaneous Endoscopic |
| 0T744DZ | Dilation of Left Kidney Pelvis with Intraluminal Device, Percutaneous Endoscopic Approach | Percutaneous Endoscopic |
| 0T768DZ | Dilation of Right Ureter with Intraluminal Device, Via Natural or Artificial Opening Endoscopic Approach | Endoscopic (Retrograde) |
| 0T778DZ | Dilation of Left Ureter with Intraluminal Device, Via Natural or Artificial Opening Endoscopic Approach | Endoscopic (Retrograde) |
PCS Character Analysis (using 0T734DZ as the reference code)
| Position | Character | Value | Definition |
|---|---|---|---|
| 1 | Section | 0 | Medical and Surgical section, encompassing the vast majority of operative procedures. |
| 2 | Body System | T | Urinary System, the body system containing the kidney, ureter, bladder, and urethra. |
| 3 | Root Operation | 7 | Dilation — “Expanding an orifice or the lumen of a tubular body part,” which best reflects widening the stenotic UPJ segment. |
| 4 | Body Part | 3 | Kidney Pelvis, Right — the specific structure at which the UPJ narrowing was incised/dilated. |
| 5 | Approach | 4 | Percutaneous Endoscopic — access via a nephrostomy/percutaneous tract using an endoscope, matching the “nephrotomy or pyelotomy” language of CPT 50575. |
| 6 | Device | D | Intraluminal Device — reflects the endopyelotomy stent left in place to splint the incised UPJ. |
| 7 | Qualifier | Z | No Qualifier — no additional qualifying detail applies to this root operation/body part/approach combination. |
Root Operation Comparison
- Dilation (7) is used here rather than Division (8) because the clinical objective and CPT descriptor emphasize widening/opening the stenotic UPJ lumen, with the incision serving as the mechanism to achieve that dilation — always verify this root operation selection against your facility’s encoder and current AHA Coding Clinic guidance, as endopyelotomy root-operation assignment has been a recurring topic of coding debate.
- If the operative approach was purely retrograde/ureteroscopic with no percutaneous renal access, select the Ureter body part (6/7) with a Via Natural or Artificial Opening Endoscopic approach (8) rather than the Kidney Pelvis/Percutaneous Endoscopic combination shown above.
- If no stent was left in place at the conclusion of the case, change the Device character from D to Z (No Device) rather than defaulting to the stented version shown in this table.
📝 Coding Examples
Example 1
Clinical Scenario: A patient with long-standing right UPJ obstruction due to a congenital stricture, previously untreated, presents for elective percutaneous antegrade endopyelotomy. A nephrostomy tract is established, the UPJ is incised under direct endoscopic and fluoroscopic visualization, and an internalized ureteral stent is placed. No stone or tumor is identified.
| Field | Code | Rationale |
|---|---|---|
| CPT | 50575--RT | Reflects the full endopyelotomy service with laterality modifier for the right-sided procedure. |
| PDx | Q62.11 | Congenital etiology is explicitly documented, distinguishing it from the acquired code N13.0. |
Note
Example 2
Clinical Scenario: A patient with left renal calculus causing secondary UPJ obstruction and hydronephrosis undergoes combined percutaneous stone extraction and endopyelotomy in a single access during the same operative session.
| Field | Code | Rationale |
|---|---|---|
| CPT 1 | 50575--LT | Represents the more extensive endopyelotomy service, the primary procedure of the encounter. |
| CPT 2 | 50580--59 | Reports the additional stone removal as a distinct component, with -59 supporting separate identification from the bundled diagnostic elements of 50575 if payer edits require it. |
| PDx | N13.2 | Captures the combined calculous and obstructive hydronephrosis etiology accurately. |
Warning
Example 3
Clinical Scenario: A patient returns to the OR fourteen days after a right endopyelotomy (50575) with acute flank pain and imaging showing stent migration requiring endoscopic repositioning by the same urologist who performed the original procedure.
| Field | Code | Rationale |
|---|---|---|
| CPT | 50575--78 | Reflects an unplanned return to the procedure room within the 90-day global period for a complication of the original endopyelotomy, performed by the same physician. |
| PDx | N13.0 | Continues to reflect the underlying obstructive diagnosis being managed. |
Global period reminder, if applicable
⚠️ Common Coding Pitfalls
- Pitfall 1: Assigning 50575 for a purely retrograde/ureteroscopic UPJ incision with no nephrotomy or pyelotomy access created. This service belongs in the cystourethroscopy-with-ureteroscopy family (52344/52345) instead, and misclassification significantly overstates the reported wRVU.
- Pitfall 2: Reporting the base diagnostic code 50570 in addition to 50575 for the same access and session. The diagnostic renal endoscopy is inherently bundled into the more extensive endopyelotomy service and should never be unbundled.
- Pitfall 3: Appending modifier -51 to a same-family multiple-endoscopy claim instead of relying on the special base-code deduction methodology tied to the Mult Proc indicator of “3.” This can result in an incorrect payment calculation if submitted with the wrong modifier logic.
- Pitfall 4: Billing an assistant surgeon claim line for CPT 50575. Because the assistant-at-surgery indicator is statutorily restricted (1), no amount of supporting documentation will result in payment, unlike indicator-0 codes where documentation can override the restriction.
- Pitfall 5: Failing to distinguish N13.0 (acquired) from Q62.11 (congenital) UPJ obstruction in the operative and history documentation, leading to a diagnosis code that does not match the clinical etiology described by the surgeon.
- Pitfall 6: Overlooking the 90-day global period when a stent removal cystoscopy or postoperative imaging-guided intervention is performed within 90 days of the endopyelotomy, resulting in an unbundling denial when those services are billed separately without an appropriate modifier or unrelated diagnosis.
📎 Sources
1. Centers for Medicare & Medicaid Services. *Physician Fee Schedule Relative Value Files, PPRRVU2026 (January Release).* CMS.gov; 2026. 2. Centers for Medicare & Medicaid Services. *National Physician Fee Schedule Relative Value File and Payment Policy Indicators.* CMS.gov; 2026. 3. American Medical Association. *CPT 2026 Professional Edition — Surgery: Urinary System.* AMA Press; 2026. 4. Centers for Medicare and Medicaid Services and the National Center for Health Statistics. *ICD-10-CM FY2026 Tabular List, Chapters 14 & 17 (Genitourinary System; Congenital Malformations).* CMS.gov; 2025. 5. AAPC. *Correct Coding Initiative: Getting to Know CCI Bundles Affecting Urology.* AAPC Coding Alert; 2016 (historical bundling reference — verify against current-quarter NCCI PTP edits).Sources listed above correspond to superscript citations throughout this note. Verify all Medicare payment figures against your current CMS PFS Lookup tool and applicable MAC LCD prior to claim submission. Please use the latest AAPC/AHIMA Coding Books to verify each code within this note.