52 y/o female with a history previous cervical cancer presents stating that she has not urinated in two days, c/o abdominal pain and some distention. i-stat labs show a creatinine of 7.5. What is the likely etiology of these findings?
Answer: Recurrent Cervical Mass with Bilateral Ureteral Obstruction
This scan demonstrates bilateral moderate hydronephrosis with an empty bladder. The most logical explanation is a proximal mass obstructing both ureters. CT confirmed recurrent invasive cervical cancer. The patient was admitted for bilateral nephrostomy tube placement – after which her renal function returned to normal.
When performing a renal ultrasound, be certain to scan both kidneys. Finding unilateral hydronephrosis may compel you to prematurely close your diagnosis to a kidney stone. Bilateral hydronephrosis in the setting of acute kidney injury is an indication for surgical intervention.
The most common causes of bilateral hydronephrosis are urinary outlet obstruction and neurogenic bladder.1
In women, ovarian, uterine, or cervical cancer should be suspected in cases of bilateral obstructive hydronephrosis.1
A curvilinear probe should be used to obtain views of the kidney in short and long axis.2
If the ribs prevent adequate long axis views of the kidney, the probe may be twisted slightly to get between the ribs (hands in pocket rib orientation). Another option is to use the smaller footprint phased array probe.
The left kidney can be more challenging to visualize. It is generally more superior and posterior than the right kidney.2
Zeidel et al. Clinical manifestations and diagnosis of urinary tract obstruction and hydronephrosis. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. (Accessed on November 19, 2014.) [UpToDate]
Dawson M, Mallin M, Introduction to bedside ultrasound volumes 1 + 2. [Inkling]