Pancreatic Stone Extracorporeal Shockwave Lithotripsy-A New Concern for Urologists?
Nitin Sharma1*,Jay A.Motola2
Copyright :© 2018 Authors. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract: Extracorporeal shock wave lithotripsy (ESWL) has been adopted by multiple medical disciplines as an effective and relatively safe modality for stone fragmentation. Complication rates are typically low but can vary from those with minimal consequence to life-threatening injuries. We report the first case of a perinephric hematoma with resulting acute kidney injury (AKI) following an intended pancreatic stone ESWL. We believe that this complication resulting from inaccurate lithotripter stone targeting of the pancreas can be prevented in the future with improved preoperative patient assessment and early urologic management in the setting of concurrent renal stones and renal pathology.
Purpose: Urologists are not familiar with pancreatic lithotripsy nor are gastroenterologists familiar with the side effects of renal lithotripsy. We present a case highlighting both of these entities.
Materials and Methods: A case of pancreatic lithotripsy is presented with the unusual complication of a perinephric hematoma.
Results: A potentially serious complication arising from an intended pancreatic lithotripsy occurred as a result of inadvertent targeting of a pancreatic stone.
Conclusions: With careful planning and collaboration between specialties, urologic complications of pancreatic lithotripsy can be avoided.
2. Case Report
Prior to ESWL treatment, the patient had a computed tomography (CT) scan revealing diffuse dilatation of the pancreatic duct with multiple large pancreatic stones within the pancreatic body and tail. A 1.6-cm renal stone, measuring 1480 Hounsfield units, was also identified at the right ureteropelvic junction (UPJ) with mild dilation of the proximal renal pelvis. However, given the patient’s persistent epigastric abdominal pain and absence of urological symptoms, the Gastroenterology service decided to proceed with pancreatic lithotripsy with plans to refer the patient to urology for renal stone management at a later date.
Preoperative laboratory blood work revealed a hematocrit of 38.3, platelet count of 200, lipase of 57, and creatinine of 1.27. All coagulation profile values were found to be within normal ranges.
The patient underwent a pancreatic ESWL under general anesthesia using a Dornier Compact Delta II Lithotripter (electromagnetic) at an ambulatory surgical center that performs high-volume pancreatic lithotripsy. A scout image was initially taken with the patient in the supine position. Two radiopacities in the body and tail of the pancreas were identified and the patient was then placed in a right posterior oblique position (RPO) with the treatment head positioned presumably over the targeted stones (Figure 2).
A total of 2500 shocks were then administered using a power setting of 1 to 4, ranging from 225 to 348 Bar. The treatment protocol consisted of an initial rate of 60 with 300 shocks administered. Voltage stepping was then used to complete the treatment. The procedure took a total of 40 minutes and fluoroscopy was performed afterwards with the finding of partial stone fragmentation.
Shortly after the treatment, while still in the recovery room, the patient complained of right-sided flank pain with nausea and gross hematuria. After an unremarkable abdominal radiograph with normal blood work and an eventual improved in symptoms following hydration and supportive care, the patient was discharged home and instructed to return for follow-up in 2-3 weeks for repeat ERCP.
Three days later, however, the patient presented to the hospital emergency room with worsening right-sided flank pain with nausea and a low-grade fever. Laboratory blood work revealed a hematocrit of 29.5, platelet count of 145, lipase of 38, and an elevated creatinine of 2.38. A CT scan without contrast was obtained revealing a moderate-sized right renal perinephric and subcapsular hematoma (Figure 3) with moderate hydronephrosis secondary to a 1.2-cm calculus at the right UPJ (Figure 4). Multiple other smaller stone fragments were also seen scattered within the renal pelvis and no interval changes were noted within the pancreatic stone burden. Urology consultation was then requested.
Due to the patient’s elevated creatinine, which was felt to be due to an obstructing UPJ stone in the setting of a perinephric hematoma, the decision was made to bring the patient to the operating room emergently for placement of an indwelling ureteral stent. A 6x24 cm pigtail stent was subsequently placed without any difficulties.
Over the next few days, the patient was managed conservatively with initial bed rest and serial hematocrit levels. One unit of packed red blood cells was transfused following a drop in hematocrit to 22.4 in the setting of worsening tachycardia. Additionally, ultrasound imaging was serially performed to ensure the stability of both perinephric and subcapsular hematomas. No evidence of hematoma expansion was evident on repeat ultrasound and after several days both hematomas were found to be stable in size with marked improvement of the previous right-sided hydronephrosis.
The patient was ultimately discharged home following 9-days of hospitalization. At the time of discharge, both hematocrit and creatinine levels had returned to near-baseline levels. A repeat CT scan performed 3-months following the initial presentation demonstrated complete resolution of both perinephric and subcapsular hematomas (Figure 5). The patient subsequently underwent an uncomplicated ureteroscopy with laser lithotripsy of the right renal stones and was rendered stone-free at the conclusion of treatment. Crystallographic analysis demonstrated the stones to be calcium oxalate dihydrate.