Endoscopic Management of Chyluria Caused by Pyelolymphatic Fistula After Robot-Assisted Laparoscopic Pyeloplasty

Abstract

Background: Chyluria is a rare diagnosis classically associated with milky-appearing urine. It involves the leakage of chyle into the urinary tract. Although the most common cause of chyluria worldwide is infectious in nature, other noninfectious etiologies have been described. Classically chyluria resolves spontaneously or with conservative management. Surgical treatments have been described but are not often required. We present a case of iatrogenic pyelolymphatic fistula after robot-assisted laparoscopic dismembered pyeloplasty that was treated with endoscopic electrocautery of the fistulous tract.

Case Presentation: A 50-year-old Caucasian man underwent a robot-assisted laparoscopic dismembered pyeloplasty with stent insertion for radiographically demonstrated left ureteropelvic junction obstruction. His postoperative course was uneventful until 4-week follow-up at which time he began to notice intermittent passage of milky-appearing urine. Urinalysis was notable for large protein and elevated urine triglycerides. He was initially managed conservatively dietary modifications without success. He then underwent endoscopic management with cystoscopy and ureteroscopy with fulguration of suspected pyelolymphatic fistula. He was maintained on a low-fat medium-chain triglyceride diet and octreotide injections while inpatient for 1 week postoperatively. His postoperative course was unremarkable and no return of chyluria was observed. His chyluria remained resolved at 9 months postoperatively.

Conclusion: Pyelolymphatic fistula after robot-assisted laparoscopic pyeloplasty is a theoretical complication of perirenal dissection and has not been previously described in the literature. It should be considered as a rare iatrogenic cause of chyluria. Endoscopic management with fulguration is technically feasible and may obviate the need for more invasive surgical management.

Introduction and Background

Chyluria is a rare diagnosis classically associated with milky-appearing urine. It involves the leakage of chyle, a mix of lymph and chylomicrons formed from free fatty acids absorbed in the small intestine, into the urinary tract. The most common cause of chyluria worldwide is chronic filariasis caused by the parasite Wucheria bancrofti causing lymphatic obstruction and destruction.¹ Other reported causes, especially in developed nations, include tumors of the kidney and retroperitoneum, surgical trauma, blunt force trauma, tuberculosis, anatomic or congenital anomalies, and pregnancy.² Most reports describe either spontaneous resolution of symptoms or conservative management techniques, including dietary changes. Surgical treatments have been described and range from endoscopic techniques to both open and robotic interventions.¹ We present a case of iatrogenic pyelolymphatic fistula after robot-assisted laparoscopic dismembered pyeloplasty that was treated with endoscopic electrocautery of the fistulous tract.

Presentation of Case

A 50-year-old Caucasian man underwent a robot-assisted laparoscopic dismembered pyeloplasty with stent insertion for radiographically demonstrated left ureteropelvic junction obstruction. A ureteral stent was left in place at the conclusion of the procedure. His postoperative course was uneventful until 4-week follow-up at which time he reported recent intermittent passage of milky-appearing urine. Urinalysis was notable for large protein and urine triglycerides were found to be >1999 mg/dL (normal <65 ng/dL). A CT scan of his abdomen and pelvis with intravenous pyelography was notable for a fluid collection medial to the repaired left ureteropelvic junction (Fig. 1). Delayed imaging showed this fluid collection was separate from the collecting system. These imaging findings in the context of his symptoms raised concern for a lymphocele and possible fistulous connection to the left collecting system. He was initially managed conservatively with a low-fat medium-chain triglyceride diet for the next 4 weeks. The ureteral stent remained in place during this time period. Despite dietary modifications, his urine remained appearing milky and urinalysis demonstrated persistent proteinuria, chylomicrons, and triglycerides. After thorough discussion of treatment options, the patient elected for attempt at endoscopic management with cystoscopy and ureteroscopy with possible intervention. After several further weeks of conservative management without improvement, he proceeded to the operating room at almost 12 weeks after his initial operation.

FIG. 1.

Fluid collection medial to the repaired ureteropelvic junction, yellow arrow marks fluid collection.

Cystoscopy was notable for milky-appearing urine freely effluxing from the ureteral stent on initial examination. Retrograde injection of contrast through a ureteral catheter adjacent to the indwelling ureteral stent revealed irregularity of the medial aspect of the ureteropelvic junction. Ureteroscopic evaluation revealed chylous drainage from a focal pinpoint opening of a fistulous tract in the medial aspect of the left ureteropelvic junction (Fig. 2). Contrast injection through ureteroscope in the area concerning for fistulous connection demonstrated uptake of contrast in ascending manner from the medial aspect of the left ureteropelvic junction (Fig. 3). This was concerning for uptake into an ascending lymphatic channel. Cannulation was attempted with a hydrophilic wire for potential sclerotherapy, but the lumen of the tract was too small to allow for insertion of a wire or injectable catheter. Endoscopic fulguration was then performed with a monopolar Bugbee electrode at 20 W with sterile water irrigation. Chylous drainage from the tract had visually ceased immediately after fulguration (Fig. 4). Ureteral stent placement was deferred to limit inflammation of the urothelial lining adjacent to the fistulous tract, and a Foley catheter was placed to monitor urine clarity.

FIG. 2.

Fistulous tract in the medial aspect of the left ureteropelvic junction, red arrow marks chylous efflux from fistula.

FIG. 3.

Uptake of contrast in ascending manner from the medial aspect of the ureteropelvic junction, red arrows mark ascending lymphatic channel with contrast.

FIG. 4.

Fistulous tract in the medial aspect of the left ureteropelvic junction after fulguration with cessation of chylous efflux, black arrow marks prior fistula site.

Postoperatively, the urine was clear yellow and the patient was started on a low-fat medium-chain triglyceride diet. He was also started on a series of octreotide injections for 1 week as this had been previously described as a conservative management option. Nutrition Services was consulted for further dietary management recommendations in the setting of chylous drainage. The role of continued dietary and pharmacologic treatment after endoscopic management is unclear, but was continued in this case in an attempt to reduce lymphatic output in proximity to the healing tract during urothelial re-epithelialization. His Foley catheter was removed at 48 hours postoperatively and he was able to void spontaneously without issue. The patient's urine remained clear throughout his hospital stay and was discharged home in good condition. He had no evidence of recurrent chyluria by 9 months postoperatively at most recent follow-up.

Discussion and Literature Review

Chyluria is an uncommon urologic condition that occurs secondary to an abnormal lymph flow from intestines to a structure of the urinary tract, including kidney, ureter, or bladder.¹ In tropical nations and developing countries, the most commonly cited cause of this condition is lymphatic filariasis, a parasitic infection caused by the parasite W. bancrofti that can lead to chronic granulomatous destruction of normal lymphatic channels and subsequent fistulous connections. This results in symptoms such as chyluria, elephantitis, chylous ascites, or chylothorax. Infectious etiologies of chyluria are rare in developed nations. In these areas, chyluria can be linked to both iatrogenic and noniatrogenic causes, including surgical or procedural trauma, blunt force trauma, tuberculosis, retroperitoneal lymphangiomas, congential lymphorenal fistulae, metanephric adenoma, thoracic duct obstruction from aortic aneurysm, or invasive lymphadenopathy from malignancy.² More common conditions, including pregnancy, diabetes, and nephrotic syndrome have also been suggested as potential nonparasitic causes of chyluria.¹ Conservative treatment traditionally consists of a restricted fat diet and nutritional therapy with medium-chain triglycerides, which bypass lymphatic uptake and are directly absorbed into the portal venous system. Interventions for refractory cases include endoscopic sclerotherapy with povidone iodine, dextrose solution, or silver nitrate, and open, laparoscopic, or robotic renal pedicle lymphatic disconnection. Intractable chyluria may necessitate a period of enteral rest with total parenteral nutrition.³

Rycyna and Casella described a case of chyluria after blunt force trauma. Cystoscopic evaluation revealed ureteral efflux of milky fluid into the bladder. A ureteral stent was placed and the patient was and managed conservatively with dietary restrictions. Rapid improvement was noted after 1 week, with clearing of urine and resolution of chyluria with no recurrence at 6-month follow-up.³ Komeya et al. reported in 2012 a case of chyluria after open partial nephrectomy using a microwave tissue coagulator. They noted no collecting system violation during their operation and did not perform lymph node dissection; however, the patient presented 2 years postoperatively with urinary retention and chyluria. He was managed with endoscopic sclerotherapy using silver nitrate with complete resolution of chyluria both immediately postprocedure and at 11-month follow-up.⁴

Conclusion

Pyelolymphatic fistula after robot-assisted laparoscopic pyeloplasty is a theoretical complication of perirenal dissection and has not been previously described in the literature. It should be considered as a rare iatrogenic cause of chyluria. Endoscopic management with fulguration is technically feasible and may obviate the need for more invasive surgical management.

Abbreviation Used

CT

computed tomography

Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.

Cite this article as: Rabley A, Pavlinec J, Kwenda E, Kuo J, Yeung L (2020) Endoscopic management of chyluria caused by pyelolymphatic fistula after robot-assisted laparoscopic pyeloplasty, Journal of Endourology Case Reports 6:4, 409–412, DOI: 10.1089/cren.2020.0160.