Transmesocolic robotic extended pyelolithotomy of a large gas-containing renal stone: Case report and review of the literature
A 31-year-old Mexican-American woman was referred for a large left renal stone found on initial work-up for flank pain and gross hematuria. She was non-diabetic and denied prior medical or surgical history. Exam was significant for mild left costovertebral angle tenderness. Urinalysis revealed positive nitrite and a pH of 5.0. Complete blood count was normal and the patient denied recent febrile illness. Urine culture was positive for E. coli resistant to trimethoprim-sulfamethoxasazole. Axial imaging showed gas in the collecting system and within several compartments of a 6.5 cm lamellated renal pelvis stone without radiographic evidence of acute infection []. Renogram demonstrated 20% left relative function and significant obstruction, with a T½ of 65 min. Serum chemistry showed no metabolic acidosis, hypercalcemia or hyperglycemia. The Cockcroft-Gault calculated creatinine clearance was 177 mL/min. Options including nephrectomy, percutaneous nephrostolithotomy (PCNL) and robotic extended pyelolithotomy were discussed with the patient. She strongly desired nephron-sparing surgery. Given the stone was large but confined to the renal pelvis, without significant branching, we felt that a robotic approach provided the most efficient means of removal.\nThe patient was taken to the operative suite and placed in a left-side up 60-degree flank position. A Veress needle was used to obtain pneumoperitoneum and a 12 mm camera port, three 8 mm robotic ports and two 5-mm assistant ports were placed. A bulge corresponding to the left kidney was easily identified in the left mesocolon. A 4-cm incision was carried through the mesocolon parallel to the vascular arcades. The renal pelvis was exposed and a transverse pyelotomy was made directly onto the stone []. Robotic forceps were used to manipulate the stone into a laparoscopic specimen retrieval bag. The renal pelvis was irrigated and found to be free of residual fragments. Inspection of the uretero-pelvic junction showed no obvious crossing vessels, narrowed segments or kinking. A 6 French ×28 cm ureteral stent was then placed in an anterograde fashion into the urinary bladder and verified by reflux of urine through the proximal stent lumen. The pyelotomy was then closed in two layers with running 3-0 poligecaperone, followed by an interrupted imbricating layer. A closed suction drain was brought into the retroperitoneum via the lateral most robotic port. The mesocolon was re-approximated and the specimen was removed by extending the inferior-most port site. Total procedure time was 120 min, with 63 min of robotic console time. The Foley catheter was removed post-op day 1. Drain output remained minimal and it was removed post-op day 2 as the patient was discharged home. The ureteral stent was removed in the office cystoscopically 4 weeks after surgery.\nGrossly, the stone was hard and non-friable. Axial sectioning revealed several hollow compartments consistent with gas pockets on pre-op imaging []. Culture of stone material revealed E. coli, also resistant to trimethoprim-sulfamethoxasole. Compositional analysis showed the stone to be 100% calcium phosphate.\nAt 12 months post-op, the patient was well and had a single episode of dysuria, which was culture negative. Renogram showed resolved left obstruction and stable relative function while calculated creatinine clearance was unchanged from pre-op. Plain abdominal radiograph and renal ultrasound were without urinary calculi.