Clarifying coding for percutaneous nephrolithotomy procedures

Your review of the new codes 50436 and 50437 in April 2023 was very informative.¹ Do you know whether Medicare has changed the National Correct Coding Initiative (NCCI) edits to allow use of these codes with 50080 and 50081? Also, is retrograde ureteroscopy with lithotripsy for ureteral stone at the time of 50081 (on the same side) now allowed? Three months ago, I reported a 50081 and 52356 with 50437, and my hospital-based coders are only allowing me to submit a 50081 based on NCCI edits.

Jonathan Rubenstein, MD

To explain this answer appropriately, we need to go back to the original description of the Current Procedural Terminology (CPT) codes that would be used for percutaneous nephrolithotomy procedures. CPT codes 50080 and 50081 were used to describe the breaking and removal of stones from a percutaneous approach, whereas CPT code 50395 was used to describe percutaneous needle access into the kidney. However, there was concern about the correct coding and description of work when an interventional radiologist also dilates the tract to a size large enough to accommodate percutaneous instrumentation, the work of which was not described or valued. Therefore, new CPT codes 50436 and 50437 were created to describe this work (dilation of a percutaneous tract without and with new access). When these codes were created, CPT code 50395 was eliminated. An NCCI edit was adopted for CPT codes 50080 and 50081 to include both codes 50436 and 50437 based on the then-current value assigned to codes 50080 and 50081.

Mark Painter

Therefore, to help mitigate this confusion and overlap of work, CPT codes 50080 and 50081 were revised, with the updated code descriptors and vignette separating the access/dilation from the stone removal procedure, which was proposed by the American Medical Association and adopted by Medicare.

These 2 codes have the following parenthetical attached:

1. For dilation of an existing percutaneous access for an endourologic procedure, use 50436.
2. For dilation of an existing percutaneous access for an endourologic procedure with new access into the collecting system, use 50437; for additional new access into the kidney, use 50437 for each new access that is dilated for an endourologic procedure.

In the CPT codebook itself, instructions for the use of these codes state the following:

• Breaking and removing stones is separate from accessing the kidney (ie, 50040, 50432, 50433, 52334), accessing the kidney with dilation of the tract to accommodate an endoscope used in an endourologic procedure (ie, 50437), or dilation of a previously established tract to accommodate an endoscope used in an endourologic procedure (ie, 50436).
• Creation of percutaneous access or dilation of the tract to accommodate large endoscopic instruments used in stone removals (50436, 50437) is not included in 50080 or 50081 and may be reported separately if performed. Codes 50080 and 50081 include the placement of any stents or drainage catheters that remain indwelling after the procedure.

The updated codes 50080 and 50081 were revised to match the new descriptions (without dilation or dilation with new access), and the proposed updated values developed by the RUC were adopted by Medicare. Unfortunately, the NCCI has refused to remove the bundling edits from the system; however, these edits allow unbundling with an appropriate modifier.

From a coding standpoint and from the work performed and valuation of the work and descriptors, it is appropriate to report the dilation (50436 without or 50437 with new access as appropriate) along with the nephrolithotomy codes (50080/50081) when both are performed at the same time by the same provider. You will need to append the appropriate modifier -59 or -XU when these are performed and reported by the same physician or physicians in the same practice and specialty. Although this would increase your use of these modifiers, you should not hesitate to report the modifiers for fear of an audit, as this is correct coding, as noted above.

REFERENCE

1. Rubenstein J, Painter M. Clearing up confusion surrounding percutaneous nephrolithotomy coding. Urology Times. April 20, 2023. Accessed December 16, 2024. https://www.urologytimes.com/view/clearing-up-confusion-surrounding-percutaneous-nephrolithotomy-coding

Send coding and reimbursement questions to Jonathan Rubenstein, MD, and Mark Painter c/o Urology Times®, at UTeditors@mjhlifesciences.com.

The information in this column is designed to be authoritative, and every effort has been made to ensure its accuracy at the time it was written. However, readers are encouraged to check with their individual carrier or private payers for updates and to confirm that this information conforms to their specific rules.