The patient is a 48‐year‐old Hispanic man who was admitted for anuria. He had a recent diagnosis of colon cancer with liver and omental metastases accompanied by malignant ascites. Beginning 1 week prior to admission, the patient noticed a gradual decrease in his urine output until he was no longer able to urinate. He had no hematuria or flank pain; he had not recently used NSAIDs or antibiotics; he had no recent illnesses, fevers, chills, nausea, vomiting, diarrhea, or constipation. On admission his blood pressure was 164/110 mm Hg; vital signs were otherwise normal. Physical examination revealed increased jugular venous pressure to the angle of the jaw, decreased breath sounds at the lung bases, abdominal distention with a fluid wave, and 1+ pitting bilateral lower‐extremity edema. He was in mild distress secondary to his abdominal distension. Laboratory studies revealed a hemoglobin of 8.1 g/dL, which was unchanged from his baseline; there was no leukocytosis. His metabolic profile demonstrated a sodium of 132 mmol/L, a potassium of 5.2 mmol/L, and a chloride of 99 mmol/L; his BUN and creatinine were elevated at 70 and 12.2 mg/dL, respectively, from a baseline BUN and creatinine of 14 and 0.8 mg/dL, respectively. Urinalysis revealed 2+ protein, 3+ leukocyte esterase, 28 RBC's/hpf, and >200 WBCs/hpf. A CT of the abdomen and pelvis revealed mild bilateral hydroureteronephrosis, which was unchanged from a CT performed 1 month prior to admission. A Foley catheter was placed with minimal urine output. Since the bilateral hydroureteronephrosis was minimal, chronic, and unchanged from previous imaging, nephrostomy tubes were not initially inserted. Ultimately, on the third hospital day bilateral percutaneous nephrostomy catheters were placed. Three days postintervention, his renal function had improved to a creatinine of 2.0 mg/dL. Such rapid improvement in his renal function indicated that his acute kidney injury was caused by bilateral ureteral obstruction.
Bilateral ureteral obstruction without significant dilation of the ureters or hydronephrosis is unusual. However, case series suggest that obstructive uropathy with minimal or no hydroureteronephrosis may be underrecognized. Between 4% and 5% of cases of obstructive uropathy resulting in acute renal failure occur without hydroureteronephrosis; approximately half of these cases arise in patients with intra‐abdominal or intrapelvic malignancies. The underlying mechanism is not well understood.
Clinicians should maintain a high index of suspicion for ureteral obstruction when a patient presents with acute oliguria or anuria, even when hydroureteronephrosis is minimal or absent. Clinicians should remain especially vigilant when intra‐abdominal or intra‐pelvic malignancies are present. The obstruction must be promptly relieved in order to remove the cause of the renal failure.
To cite this abstract:Shah M, Bates J. Obstructive Nephropathy Without Significant Hydroureteronephrosis. Abstract published at Hospital Medicine 2013, May 16-19, National Harbor, Md. Abstract 367. Journal of Hospital Medicine. 2013; 8 (suppl 2). https://www.shmabstracts.com/abstract/obstructive-nephropathy-without-significant-hydroureteronephrosis/. Accessed September 18, 2019.