PYELOSTOLITHOTOMY is a surgical procedure for the removal of calculi (stones) from the renal pelvis by making an incision directly into the renal pelvis (pyelotomy) to extract the stone, typically performed when a large isolated renal pelvic stone is accessible via the pelvis without requiring incision into the kidney parenchyma itself. It is distinguished from nephrostolithotomy (50060-50081 range), which involves incision into the kidney parenchyma (nephrotomy) for stones within the calyces or intrarenal collecting system, and from ureterolithotomy (50610-50630 range), which addresses ureteral stones rather than renal pelvic stones, and from percutaneous nephrostolithotomy (PCNL; 50080-50081), which uses minimally invasive percutaneous tract-based access rather than open surgical incision. The underlying mechanism involves direct surgical access to the renal pelvis—typically through an open flank or lumbotomy incision with mobilization of the kidney, identification of the renal pelvis, and pyelotomy (incision into the pelvis) to allow stone extraction—preserving the renal parenchyma and minimizing risk of bleeding or parenchymal injury compared to nephrotomy. Clinically relevant subtypes include standard pyelolithotomy (simple incision into dependent portion of renal pelvis for single large pelvic stone; CPT 50130), extended pyelolithotomy (larger pyelotomy or combined with minor calyceal incision for stones extending from pelvis into infundibulum; still coded 50130 if primarily pelvic), coagulum pyelolithotomy (historical technique using fibrin glue coagulum to trap stone fragments during extraction; rarely performed in modern practice; 50130 with documentation), and laparoscopic pyelolithotomy (minimally invasive laparoscopic approach for renal pelvic stone removal; CPT 50545). Pyelostolithotomy can be physiological (not applicable—this is purely a surgical intervention) or pathological (performed for symptomatic or obstructing renal pelvic calculi causing pain, infection, or hydronephrosis; coded under N20.0 for calculus of kidney). It differs from pyeloplasty (50400-50405), which is reconstruction of the ureteropelvic junction (UPJ) for congenital or acquired obstruction rather than stone removal, and from pyelotomy alone (incision without stone removal; typically coded as part of another procedure or with unlisted code), where pyelostolithotomy specifically denotes the incision plus stone extraction.
Greek -tomia (-toh-MEE-ah), from temnein (TEM-nayn)
Noun-forming suffix — “act of cutting,” “incision into,” “surgical cutting”
The word entered English in the 1880s-1890s as pyelostolithotomy (noun), borrowed from New Latin pyelostolithotomia, from Greek pyelos + lithos + -tomia — literally “cutting into the renal pelvis for a stone.” The term became standard surgical nomenclature in urology with the development of open stone surgery techniques in the late 19th and early 20th centuries, distinguishing renal pelvic stone removal (pyelolithotomy) from parenchymal stone removal (nephrolithotomy) based on the surgical approach and anatomic target. The adjective form pyelolithotomy (used attributively) appears in operative reports as “pyelolithotomy incision,” “pyelolithotomy approach,” or “post-pyelolithotomy drain.” Note that pyelolithotomy and pyelostolithotomy are used interchangeably in clinical practice and coding, with pyelolithotomy being the more common shortened form (similar to how “nephrostolithotomy” is often shortened to “nephrolithotomy”). The root pyelos (“renal pelvis”) connects pyelostolithotomy to the entire pyelo- family: pyelonephritis (pyelo- [renal pelvis] + nephr- [kidney] + -itis [inflammation] → infection of renal pelvis and kidney parenchyma), pyeloplasty (pyelo- [renal pelvis] + -plasty [surgical repair] → reconstruction of the ureteropelvic junction), pyelography (pyelo- [renal pelvis] + -graphy [imaging] → radiographic visualization of the renal pelvis), hydronephrosis (hydro- [water] + nephr- [kidney] + -osis [condition] → swelling of kidney including renal pelvis from urinary obstruction), and pyelotomy (pyelo- [renal pelvis] + -tomy [incision] → incision into the renal pelvis without stone removal, typically performed for access or drainage). The stone-denoting rootlitho- is highly productive in medical terminology, appearing in urolithiasis (uro- [urine] + lith- [stone] + -iasis [condition] → urinary stone disease), nephrolithiasis (nephro- [kidney] + lith- [stone] + -iasis → kidney stones), lithotripsy (litho- [stone] + -tripsy [crushing] → stone fragmentation), ureterolithotomy (uretero- [ureter] + litho- [stone] + -tomy [incision] → surgical removal of ureteral stone), and cholelithiasis (chole- [bile] + lith- [stone] + -iasis → gallstones). The surgical suffix-tomy (“cutting into”) distinguishes pyelostolithotomy from pyelostomy (-stomy [creation of opening] → creation of external opening from renal pelvis for drainage) and from pyelonephrectomy (-ectomy [removal] → removal of renal pelvis and kidney together).
🔀 ALIASES / ALTERNATE TERMS
Pyelolithotomy(shortened clinical synonym and preferred CPT terminology; used interchangeably with pyelostolithotomy in operative reports, coding documentation, and urology literature; both terms refer to the same procedure—incision into renal pelvis with stone removal; CPT 50130 descriptor uses “pyelotomy; with removal of calculus [pyelolithotomy]”)
Renal pelvic stone removal(lay and clinical descriptor; used in patient education materials, informed consent documents, and discharge summaries to describe the procedure in plain language)
Pelviolithotomy(alternate clinical synonym emphasizing the pelvic location; less commonly used than pyelolithotomy but appears in older urology literature and some operative notes)
Pyelotomy with stone removal(descriptive clinical phrase; “pyelotomy” alone refers to incision into the renal pelvis [typically for access or drainage], while “with stone removal” specifies the lithotomy component; used in operative note titles)
Renal pelvis incision for stone(lay descriptor synonym; patient-friendly terminology used in pre-operative counseling and patient education materials)
Open pyelolithotomy(etiologic/technical subtype — traditional open surgical approach via flank or lumbotomy incision with direct visualization of renal pelvis; distinguishes from laparoscopic approach; CPT 50130)
Laparoscopic pyelolithotomy(etiologic/technical subtype — minimally invasive laparoscopic approach for renal pelvic stone removal using laparoscopic instruments and camera; CPT 50545; increasingly preferred over open approach when technically feasible)
Extended pyelolithotomy(technical subtype — pyelolithotomy with extended pyelotomy incision or minor extension into infundibulum for stones that bridge from pelvis into upper ureter or major calyx; still coded 50130 if pelvis is primary site)
Coagulum pyelolithotomy(historical technical subtype — open pyelolithotomy using fibrin glue or cryoprecipitate coagulum injected into pelvis to entrap stone fragments and facilitate complete removal; described by Dees in 1940s-1950s; rarely used in modern practice due to availability of PCNL and flexible ureteroscopy; coded 50130 with documentation of coagulum technique)
Simple pyelolithotomy(clinical descriptor — straightforward pyelolithotomy for single large accessible renal pelvic stone without anatomic complexity or prior surgery; CPT 50130)
Complex pyelolithotomy(clinical descriptor — pyelolithotomy complicated by anatomic anomalies [horseshoe kidney, ectopic kidney], prior surgery with scarring, or large/complex stone burden; may justify modifier -22 for increased complexity on CPT 50130)
Pyelotomy for calculus(alternate descriptor phrase emphasizing the incisional component; “pyelotomy” = incision, “for calculus” = indication; used interchangeably with pyelolithotomy)
🔗 RELATED TERMS
Nephrostolithotomy — shares the litho- and -tomy roots; surgical removal of kidney stone via incision into the kidney parenchyma (nephrotomy) rather than just the renal pelvis; distinguished from pyelostolithotomy by the need to incise renal tissue to access calyceal or intrarenal stones not accessible via pelvic approach; CPT codes 50060-50075 (open) or 50080-50081 (percutaneous)
Nephrolithiasis — shares the litho- root; the presence of calculi (stones) within the kidney, including renal pelvis, calyces, and intrarenal collecting system; the underlying condition for which pyelostolithotomy is performed; coded N20.0 (calculus of kidney)
Ureterolithotomy — shares the litho- and -tomy roots; surgical removal of a stone from the ureter rather than the renal pelvis; distinguished from pyelostolithotomy by the anatomic location (ureter vs. renal pelvis); CPT codes 50610 (upper third), 50620 (middle third), 50630 (lower third)
Pyeloplasty — shares the pyelo- root; surgical reconstruction of the ureteropelvic junction (UPJ) to relieve congenital or acquired obstruction; distinguished from pyelostolithotomy by the surgical goal (reconstruction vs. stone removal) and by the absence of stone disease; CPT 50400 (open), 50405 (open, intra-renal), 50544 (laparoscopic)
Pyelotomy — shares the pyelo- and -tomy roots; surgical incision into the renal pelvis without stone removal; pyelotomy is the incisional component of pyelostolithotomy; when performed alone (e.g., for exploration, biopsy, or drainage), it may be coded as part of another procedure or with an unlisted code; pyelostolithotomy specifically denotes pyelotomy plus stone extraction
Pyelonephritis — shares the pyelo- root; infection of the renal pelvis and kidney parenchyma; acute pyelonephritis is a contraindication to elective pyelostolithotomy (infection must be treated first to minimize risk of bacteremia and sepsis); chronic pyelonephritis and recurrent infections may be complications of untreated renal pelvic stones; coded N10
Hydronephrosis — shares the pyelo- root (involves dilation of renal pelvis); swelling of the kidney from obstruction of urine outflow, often caused by renal pelvic stones; moderate to severe hydronephrosis from large pelvic stones is a common indication for pyelostolithotomy; coded N13.30 (unspecified) or N13.2 (with calculous obstruction)
Percutaneous nephrostolithotomy — shares the litho- root; minimally invasive percutaneous removal of kidney stones via tract-based access with nephroscopy; distinguished from open pyelostolithotomy by the percutaneous approach; PCNL is preferred for large intrarenal or calyceal stones, while pyelostolithotomy is preferred for large isolated renal pelvic stones accessible via open pelvic approach; CPT 50080 (stone up to 2 cm) or 50081 (stone over 2 cm)
Lithotripsy — shares the litho- root; fragmentation of stones using shock wave, laser, ultrasonic, or pneumatic energy; extracorporeal shock wave lithotripsy (ESWL; 50590) is first-line treatment for stones <2 cm, while pyelostolithotomy is reserved for large (typically >2.5-3 cm) renal pelvic stones not amenable to ESWL or PCNL
Ureteroscopy — endoscopic visualization and treatment of the ureter and renal pelvis via retrograde transurethral access; flexible ureteroscopy with laser lithotripsy (52356) can treat some renal pelvic stones retrograde without incision, though large pelvic stones (>2.5 cm) may require open or laparoscopic pyelolithotomy
Staghorn calculus — large branching renal stone occupying the renal pelvis and extending into ≥2 calyces; distinguished from isolated renal pelvic stones by the calyceal extension; complete staghorn calculi typically require nephrostolithotomy (especially PCNL or anatrophic nephrolithotomy; 50081, 50075) rather than pyelostolithotomy alone, as the calyceal component cannot be accessed via pelvic incision
Pyelography — shares the pyelo- root; radiographic imaging of the renal pelvis and collecting system using contrast medium; includes intravenous pyelography (IVP) and retrograde pyelography; used preoperatively to define stone size and location and intraoperatively during pyelostolithotomy to confirm stone clearance
Pyonephrosis — shares the pyelo- root; infected hydronephrosis with pus in the renal pelvis and collecting system; a urologic emergency often caused by obstructing renal pelvic stones; requires emergent percutaneous nephrostomy drainage (50392) prior to definitive pyelostolithotomy; coded N13.6
Ureteropelvic junction obstruction — congenital or acquired narrowing at the UPJ causing hydronephrosis; abbreviated UPJ obstruction; may coexist with renal pelvic stones (obstruction predisposes to stone formation and impairs stone passage); when both are present, combined pyeloplasty and pyelolithotomy may be performed (CPT 50405 for pyeloplasty with stone removal)
Renal pelvis — the funnel-shaped collecting structure of the kidney that receives urine from the major calyces and drains into the ureter; the anatomic target of pyelostolithotomy; large renal pelvic stones form within this space and are accessible via pyelotomy without parenchymal incision
CODING CORNER
🏥 ICD-10-CM CODES
Renal Calculus (Primary Indication for Pyelostolithotomy)
Calculus of kidney (nephrolithiasis; includes renal pelvic stones, calyceal stones, and staghorn calculi; primary indication for pyelostolithotomy when stone is isolated to renal pelvis)
Calculus of kidney with calculus of ureter (combined renal and ureteral stone disease; may require staged or simultaneous pyelolithotomy and ureterolithotomy)
Obstructive Uropathy and Hydronephrosis (Complications/Indications)
Hydronephrosis with renal and ureteral calculous obstruction (stone-induced kidney swelling; indication for urgent pyelostolithotomy when stone is large or obstructing; documents medical necessity for surgical intervention)
Unspecified hydronephrosis (kidney swelling from any cause; chronic hydronephrosis from large renal pelvic stones is indication for pyelostolithotomy to preserve renal function)
Pyonephrosis (infected hydronephrosis with pus in collecting system; urologic emergency requiring emergent percutaneous nephrostomy drainage prior to elective pyelostolithotomy; absolute contraindication to elective stone surgery until infection controlled)
Metabolic Stone Disease (Underlying Etiologies)
Code
Description
E72.01
Cystinuria (hereditary disorder causing cystine stones; cystine calculi are hard and radio-lucent, often forming large renal pelvic stones requiring open or laparoscopic pyelolithotomy)
E83.59
Other disorders of calcium metabolism (includes hypercalciuria, hyperoxaluria, and other metabolic causes of calcium-based renal pelvic stones)
E79.0
Hyperuricemia without signs of inflammatory arthritis and tophaceous disease (may lead to uric acid nephrolithiasis; uric acid stones are radiolucent and may form large renal pelvic calculi)
Urinary tract infection, site not specified (common with struvite stones; infection with urease-producing bacteria may lead to large renal pelvic stones; acute UTI is relative contraindication to elective pyelolithotomy)
Acute pyelonephritis (kidney infection; absolute contraindication to elective pyelostolithotomy; infection must be treated and cleared before stone surgery to minimize risk of sepsis)
Ureteropelvic Junction (UPJ) Obstruction (May Coexist with Renal Pelvic Stones)
Hydronephrosis with ureteropelvic junction obstruction (congenital or acquired UPJ narrowing causing hydronephrosis; predisposes to renal pelvic stone formation; may require combined pyeloplasty and pyelolithotomy)
Q62.11
Congenital occlusion of ureteropelvic junction (congenital UPJ obstruction; predisposes to stone formation in dilated renal pelvis)
Postoperative Complications
Code
Description
N99.89
Other postprocedural complications and disorders of genitourinary system (includes post-pyelolithotomy complications such as urinary leak, urinoma, perinephric hematoma, or persistent hydronephrosis)
T81.44XA
Sepsis following a procedure, initial encounter (postoperative urosepsis complicating pyelostolithotomy; rare but serious complication, especially if struvite stone or pyonephrosis present)
N99.0
Postprocedural (acute) (chronic) kidney failure (postoperative AKI; rare but may occur after pyelolithotomy in patients with solitary kidney, bilateral procedures, or pre-existing chronic kidney disease)
🔧 COMMON CPT CODES (Pyelostolithotomy and Related Procedures)
CPT Code
Description
50130
Pyelotomy; with removal of calculus (pyelolithotomy) (primary CPT code for open pyelostolithotomy; includes flank or lumbotomy incision, mobilization of kidney, pyelotomy, stone extraction, pyelotomy closure, and drain placement; used for isolated large renal pelvic stones accessible via pelvic approach)
Laparoscopy, surgical; radical nephrectomy (includes removal of Gerota’s fascia, ipsilateral adrenal gland and regional lymph nodes) (NOTE: This code is for radical nephrectomy; laparoscopic pyelolithotomy is typically coded with 50130 using modifier for laparoscopic approach or unlisted laparoscopic code 50949 with comparison to 50130—verify payer-specific coding guidelines)
Unlisted laparoscopy procedure, renal (use for laparoscopic pyelolithotomy when specific CPT code not available; requires operative report submission and comparison to open pyelolithotomy 50130 for reimbursement; document reduced morbidity, smaller incision, faster recovery vs. open approach)
50405
Pyeloplasty (Foley Y-pyeloplasty), plastic operation on renal pelvis, with or without plastic operation on ureter, nephropexy, nephrostomy, pyelostomy, or ureteral splinting; complicated (including congenital kidney abnormalities, secondary pyeloplasty and/or solitary kidney) (used when pyeloplasty for UPJ obstruction is combined with stone removal; “with or without” language in descriptor allows for concurrent pyelolithotomy without separate code; document both UPJ obstruction and stone disease)
50400
Pyeloplasty (Foley Y-pyeloplasty), plastic operation on renal pelvis, with or without plastic operation on ureter, nephropexy, nephrostomy, pyelostomy, or ureteral splinting; simple (may be used with concurrent stone removal when pyeloplasty is primary procedure and stone extraction is incidental; document both procedures separately)
Percutaneous nephrostolithotomy or pyelostolithotomy, with or without dilation, endoscopy, lithotripsy, stenting, or basket extraction; up to 2 cm (percutaneous approach to renal pelvic stone; alternative to open pyelolithotomy; increasingly preferred for stones ≤2 cm due to reduced morbidity)
Percutaneous nephrostolithotomy or pyelostolithotomy, with or without dilation, endoscopy, lithotripsy, stenting, or basket extraction; over 2 cm (percutaneous approach for large renal pelvic stones >2 cm; alternative to open pyelolithotomy 50130; often preferred over open approach unless anatomy unfavorable or prior failed PCNL)
50392
Introduction of intracatheter or catheter into renal pelvis for drainage and/or injection, percutaneous (percutaneous nephrostomy tube placement by interventional radiology; used for emergent drainage in pyonephrosis or obstructive uropathy prior to definitive pyelolithotomy; first-stage drainage before stone surgery)
50393
Introduction of ureteral catheter or stent into ureter through renal pelvis for drainage and/or injection, percutaneous (antegrade ureteral stent placement via nephrostomy; may be placed after pyelolithotomy for temporary urinary drainage and to prevent ureteral obstruction from edema or stone fragments)
Cystourethroscopy, with ureteroscopy and/or pyeloscopy; with removal or manipulation of calculus (retrograde ureteroscopic basket extraction of renal pelvic stone; alternative to pyelolithotomy for smaller stones <2 cm; less invasive but may require multiple sessions)
Cystourethroscopy, with ureteroscopy and/or pyeloscopy; with lithotripsy (retrograde flexible ureteroscopy with laser lithotripsy of renal pelvic stone; alternative to open pyelolithotomy for stones <2.5 cm; may require multiple sessions for complete clearance)
Lithotripsy, extracorporeal shock wave (ESWL; noninvasive stone fragmentation using focused shock waves; first-line treatment for renal pelvic stones <2 cm; less effective for large pelvic stones >2.5 cm that may require pyelolithotomy)
Urography, retrograde, with or without KUB (retrograde pyelogram; performed intraoperatively during pyelolithotomy to define anatomy, confirm stone location, and verify complete stone clearance after extraction)
76770
Ultrasound, retroperitoneal (eg, renal, aorta, nodes), real time with image documentation; complete (preoperative renal ultrasound to assess hydronephrosis, stone size, and renal anatomy prior to pyelolithotomy; postoperative ultrasound to confirm resolution of hydronephrosis)
Increased procedural services (append to 50130 when pyelolithotomy requires significantly greater complexity than typical—e.g., large stone burden >4 cm, horseshoe kidney, ectopic kidney, severe adhesions from prior surgery, morbid obesity, or coexisting anatomic anomalies; requires detailed operative note documentation explaining increased complexity and operative time)
Bilateral procedure (append to 50130 when pyelolithotomy performed on both kidneys in same operative session; rare but may occur in patients with bilateral large renal pelvic stones; typically increases reimbursement to 150% of unilateral allowable; requires documentation of bilateral stone disease and medical necessity for simultaneous bilateral surgery)
Multiple procedures (append to secondary procedure code when multiple distinct procedures performed in same operative session; e.g., pyelolithotomy with concurrent ureterolithotomy for combined renal pelvic and ureteral stones; reduces reimbursement for secondary procedure to 50-80% of full RVU)
Distinct procedural service (append to indicate that a procedure is separate and distinct from other services performed on the same day; used to override NCCI edits when procedures are performed at different anatomic sites or via separate incisions; e.g., right pyelolithotomy with left ureterolithotomy)
Unplanned return to the operating room for a related procedure during the postoperative period (append when patient requires second-look pyelolithotomy for retained stone fragments or evacuation of perinephric hematoma within global period of initial procedure; indicates complication requiring reoperation)
Unrelated procedure or service by the same physician during the postoperative period (append when patient requires unrelated surgical procedure during global period of pyelolithotomy; establishes new global period for unrelated procedure)
Right side (laterality modifier; append to **50130 to indicate pyelolithotomy performed on right kidney; e.g., 50130-RT; required for claims processing and anatomic specificity)
Left side (laterality modifier; append to 50130 to indicate pyelolithotomy performed on left kidney; e.g., 50130-LT; required for claims processing and anatomic specificity)
⚠️ Coding Note: Pyelostolithotomy (coded as pyelolithotomy) requires careful distinction from nephrostolithotomy based on anatomic site and surgical approach—pyelolithotomy (50130) involves incision into the renal pelvis only to remove an isolated renal pelvic stone accessible via pelvic approach, while nephrostolithotomy (50060-50075 for open or 50080-50081 for percutaneous) involves incision into the kidney parenchyma or calyces to access intrarenal or calyceal stones not reachable via the pelvis. The key documentation trigger for 50130 is operative note language such as “pyelotomy,” “incision into renal pelvis,” “renal pelvic stone,” or “stone extracted via pelvic approach”—this language supports pyelolithotomy coding; if the note states “nephrotomy,” “incision into kidney parenchyma,” “calyceal stone,” or “percutaneous tract,” query for clarification and code as nephrostolithotomy instead. An undercoding alert: when a provider documents “open stone removal,” “renal calculus removal,” or “kidney stone surgery” without specifying whether the incision was into the pelvis (pyelotomy) or parenchyma (nephrotomy), query for anatomic specificity—the distinction between 50130 (pyelolithotomy) and 50060 (nephrostolithotomy) significantly impacts reimbursement, with 50060 carrying higher RVUs due to greater complexity and bleeding risk from parenchymal incision. For laparoscopic pyelolithotomy, coding is challenging as there is no specific CPT code—options include: (1) reporting 50130 without modifier (some payers accept this as approach-agnostic), (2) reporting 50130 with modifier -22 (increased complexity) and documentation of laparoscopic technique, or (3) reporting unlisted laparoscopic code 50949 with comparison to 50130 and submission of operative report—verify payer-specific guidelines before coding laparoscopic pyelolithotomy, as policies vary. When pyelolithotomy is combined with pyeloplasty for concurrent UPJ obstruction and renal pelvic stone, code 50405 (complicated pyeloplasty) or 50400 (simple pyeloplasty) as the primary procedure—the CPT descriptor “with or without plastic operation on ureter, nephropexy, nephrostomy, pyelostomy, or ureteral splinting” allows for concurrent stone removal without separate code; document both UPJ obstruction (N13.0) and renal calculus (N20.0) as diagnoses to support medical necessity. Laterality modifiers -RT or -LT are required on all pyelolithotomy claims (50130-RT or 50130-LT) for anatomic specificity—failure to append laterality modifiers may result in claim denial or payer request for additional information. Modifier -50 (bilateral procedure) is rarely used for pyelolithotomy as bilateral large renal pelvic stones requiring open surgery in a single session are uncommon—if bilateral pyelolithotomy is performed, document medical necessity (e.g., bilateral symptomatic stones, renal insufficiency requiring preservation of all nephrons, patient unable to tolerate staged procedures) and expect reimbursement at 150% of unilateral allowable rather than 200%.
TABLE definition AS Definition FROM #medterm WHERE length(filter(roots, (word) => econtains([[pyelostolithotomy]].roots, word))) > 0 AND file.name != [[pyelostolithotomy]].file.name SORT file.name ASC
Query functionality
TABLE definition AS Definition FROM #medterm WHERE length(filter(definition, (word) => econtains([[pyelostolithotomy]].definition, word))) > 0 AND file.name != [[pyelostolithotomy]].file.name
Med rootsAppendix A PrefixesAppendix B Combining FormsAppendix C SuffixesAppendix D Suffix forms
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