2019 Research Forum

Tushar Bajaj MD R1, Hanh Duong MS III, Dave Holt MS III, Jasmine Ho PharmD, Sudhagar Thangarasu MD, David Aguirre MD Atypical Presentation of Obstructive Anuria

Introduction Anuria is the lack of urine production less than 50 milliliters in a 24 hour period by the kidneys which may be secondary to intrinsic or extrinsic factors. A myriad of etiologies can lead to anuria including but not limited to renal impairment, urinary tract obstruction, drugs, or severe infections. Diagnosis is assisted by results of bladder catheterization, cystourethroscopy, and imaging (eg, ultrasonography, CT, pyelography), depending on the level of obstruction. Obstructive uropathy is a common cause of anuria that is easy to diagnose; however, we present a difficult diagnosis of a patient with an extensive medical history that includes nephrectomy and a recent radical prostatectomy.

1. Pfister SA, Deckart A, Laschke S, et al. Unenhanced helical computed tomography vs intravenous urography in patients with acute flank pain: accuracy and economic impact in a randomized prospective trial. Eur Radiol 2003; 13:2513. 2. Smith RC, Verga M, McCarthy S, Rosenfield AT. Diagnosis of acute flank pain: value of unenhanced helical CT. AJR Am J Roentgenol 1996; 166:97. 3. Daniel L., Stephanie J., Beth A. V, et al. The Patient Burden of Bladder Outlet Obstruction after Prostate Cancer Treatment. Journal of Urology May 1, 2016 4. Bryk, Darren J. et al. A Case of Metastatic Prostate Cancer to the Urethra that Resolved after Androgen Deprivation Therapy. Urology. 2019 Mar 29. pii: S0090-4295(19)30323-1. doi: 10.1016/j.urology.2019.03.022. 5. Bei Z, Bingyang B, Lirong B, Zhuo W, et al. Cystic metastasis of prostate cancer: A case report. Medicine (Baltimore). 2018 Dec;97(50):e13697. Doi:10.1097/MD.0000000000013697 6. Halle MP, Toukep LN, Nzuobontane SE, Ebana HF, Ekane GH, Priso EB. The profile of patients with obstructive uropathy in Cameroon: case of the Douala General Hospital. Pan Afr Med Conclusions In our unusual presentation of obstructive anuria, our approach to treatment was challenged by the patient’s worsening kidney function and insufficient evidence from imaging. Patient’s significant medical history of prostate cancer also required investigation. In patients with unclear pathology causing oliguria or anuria, imaging with contrast should be considered in light of the patient’s morbidity and the necessity for immediate resolution. Also, taking into account the risk of irreversible kidney injury, we should strongly consider dialysis to allow imaging with contrast to be done without fear of nephrotoxicity. References

Case presentation

A 64 year old with a history of right nephrectomy (1986), prostate cancer (diagnosed 10/2018) status post radical prostatectomy (10/2018) presents to the emergency department for acute abdominal pain and 13 episodes of non-bloody non-bilious emesis for one day. At home, patient had a sudden onset of nausea and vomiting with abdominal pain. He describes it as sharp, intermittent, in the left mid-quadrant radiating to epigastric lasting 7 hours. Since his prostatectomy, patient has been incontinent of urine, but accompanying that initial episode of emesis, he noticed a cessation of urine production. On examination, patient was afebrile with diffuse abdominal tenderness, distension; no costovertebral tenderness. Laboratory results showed elevated BUN 34 and creatinine 2.82 without leukocytosis or lactic acidosis. A Foley catheter was placed and produced no urine. A total of 5 liters of fluid was given, but patient remained anuric. CT of abdomen and pelvis without contrast confirmed placement of Foley catheter and revealed perinephric stranding, multiple renal cysts without hydronephrosis. Radiographic cystogram was negative for mass lesions in the bladder and vesicoureteral reflux. 3 days later, patient continued to endorse diffuse abdominal pain with BUN and creatinine 62 and 8.03. Decision was made for placement of tunnel catheter for hemodialysis. Patient’s abdominal pain improved with BUN and creatinine to 51 and 8.20, but he was still anuric. Considering the availability of dialysis, patient had CT of abdomen and pelvis with contrast done with immediate hemodialysis after. It showed mild hydroureter and hydronephrosis with non-obstructive 3mm stone at the ureterovesicular junction, and ureteric sludge distally. Patient underwent stent placement in the OR. Immediately, patient had normal urine production, and improvement of renal function; BUN and creatinine trending downwards to 15 and 2.58 from 47 and 10.10 pre-operatively. Discussion Patients presenting with anuria or acute flank pain with suspected nephrolithiasis should have CT imaging without contrast done to rule out an obstruction. CT imaging is the modality of choice for its high diagnostic accuracy and low cost without the risk of radiation exposure compared to intravenous urography. It confirms the absence or presence of kidney stones as well as revealing other extraurinary causes contributing to acute flank pain [1,2]. With our patient, initial CT imaging without contrast failed to support the diagnosis of obstructive nephrolithiasis. And with the patient’s age and medical history significant for prostate cancer, the investigation was then focused on other pathologies. A study showed that patients who have undergone prostate cancer therapy are more susceptible to having bladder outlet obstruction [3]. Although prostate cancer typically metastasizes to the bone, it is possible to have metastasis to the urethra and bladder [4,5]. During this time, the patient’s condition continued to deteriorate with worsening abdominal pain and kidney function. The decision to start dialysis was warranted since obstructive uropathy can lead to irreversible kidney damage if left untreated. Emergency dialysis done in patients presenting with renal failure secondary to obstructive uropathy has shown to improve kidney function except in cases of underlying malignancies [6]. In addition, dialysis in our patient allowed imaging with contrast to be done without causing further insult to the kidney.

Computed Tomography of the abdomen and pelvis with contrast: 3 mm non-obstructive calculus

J. 2016;23:67. Published 2016 Mar 3. doi:10.11604/pamj.2016.23.67.8170

Computed Tomography of the abdomen and pelvis with contrast: high density material in the left ureter may represent ureteric wall edema or debris distal to the left ureter

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