Abstract: PUB011
Nondilated Obstructive Uropathy as a Reversible Cause of AKI
Session Information
Category: Acute Kidney Injury
- 102 AKI: Clinical, Outcomes, and Trials
Authors
- Dalal, Aashvi R., Weill Cornell Medicine, New York, New York, United States
- Glezerman, Ilya, Weill Cornell Medicine, New York, New York, United States
Introduction
Obstructive uropathy is a reversible cause of acute kidney injury (AKI) in cancer patients, but diagnosis depends on imaging evidence of hydronephrosis. In advanced malignancy, urinary obstruction may occur without dilation. We present two cases of nondilated obstruction causing severe AKI despite nondiagnostic imaging.
Case Description
A 65 year old woman with cervical cancer on Paclitaxel, chronic kidney disease, chronic right hydronephrosis with right renal atrophy, presented with creatinine of 11.8 mg/dL (baseline 1.6) in routine labs. She reported reduced urine output without systemic symptoms. CT imaging revealed unchanged severe right hydronephrosis with Right renal atrophy and normal left kidney. Renal ultrasound similarly showed only chronic right hydronephrosis and 13 cm Left kidney. She eventually underwent percutaneous nephrostomy with antegrade nephrogram demonstrated mild left hydronephrosis with possible mid ureteral obstruction. Renal function subsequently returned to baseline.
A 65 year old man with metastatic Merkel cell carcinoma recently recovered from checkpoint inhibitor associated AKI after steroids with creatinine improving to 1.2 mg/dl. CT abdomen with contrast performed three days before presentation showed increasing peritoneal and retroperitoneal implants but no hydronephrosis. He presented with abdominal discomfort and nausea. Creatinine was 4.2 mg/dL.Despite intravenous fluids and empiric steroids for presumed recurrent interstitial nephritis, kidney function worsened to creatinine 9.6 mg/dL. Repeat CT remained unchanged without hydronephrosis. He underwent bilateral percutaneous nephrostomies and pyelogram revealed mild to moderate hydronephrosis. Creatinine improved to 2.3 mg/dL at discharge.
Discussion
Nondilated obstruction is difficult to diagnose cause of AKI in cancer population but clinically significant in patients with prior obstruction or extensive retroperitoneal disease. A high index of suspicion is essential, when AKI is unexplained or progresses despite supportive care. Routine imaging may fail to detect obstruction, resulting in delays in recognition and treatment and thus antegrade or retrograde pyelography is required for diagnosis. Diuretic scintigraphy can be considered, although has limited accuracy in advanced renal failure. Early decompression remains critical to recovery.