We had a patient earlier this month who presented with a creatinine that was 20 mg/dL on admission and rose to 22 on the repeat. That is the highest creatinine I have ever seen in a patient with acute kidney injury. I have a seen two patients with advanced CKD with creatinines in the mid to high thirties. (34 and 37 mg/dL).
When my fellow described the patient I was sure this was going to be CKD until she mentioned, rather triumphantly, that when she examined the patient she palpated a large bladder. She had a Foley placed and the patient voided 1300 mL of urine in the next hour.
Obstructive uropathy in a woman is cervical cancer until proven otherwise. Sure enough, a subsequent CT scan of the pelvis revealed a pelvic mass which was diagnosed as cervical cancer.
The patient was discharged with a creatinine of 1.9 mg/dL.
A few aspects of the case were interesting and surprising:
- Obstructive uropathy causes an electrogenic type 1 RTA (hyperkalemic type 1 RTA as opposed to the hypokalemic classic type 1 RTA). Because of the RTA, these patients often have hyperkalemia out of proportion to the degree of renal failure. She was not hyperkalemic and presented with a potassium of 4.6 mEq/L.
- The patient had a pH of 7.2, bicarbonate of 4 and a pCO2 of 8, giving her a metabolic acidosis and a respiratory alkalosis (predicted pCO2 by Winter’s formula is 14±2). I had been taught that patients cannot blow off CO2 below 14 mmHG. I guess she had super lungs. As best we could tell, the respiratory alkalosis was due to anxiety and resolved the following day.
- My fellow wanted to give bicarbonate for the metabolic acidosis, but I did not. The pH of 7.2 is fine and the patient was hemodynamically stable. Her total calcium was 4.6 and her phosphorous was 10. I was worried that giving bicarbonate would correct the acidosis which at the time was essential to prevent the hypocalcemia from causing tetany or worse. The acidosis shifts bound inactive calcium to the unbound and active ionized form.
“Obstructive uropathy in a woman is cervical cancer until proven otherwise. Sure enough, a subsequent CT scan of the pelvis revealed a pelvic mass which was diagnosed as cervical cancer.”
Very curious to know more about this…and how often you encounter such occurances??
Obstructive uropathy is most commonly due to prostate disease or is drug induced from cold remedies or other anti-cholinergic medications. Obviously woman can’t have prostatic disease so residents are often flummoxed when trying to explain the cause of bilateral obstruction in a woman. Cervical cancer must be on the differential in these situations. During my fellowship I saw 10 or 12 cases of gyn cancer causing urinary obstruction in woman. Whether it is cervical cancer or ovarian cancer is less important that thinking immediately about a malignancy and ordering the appropriate imaging test.
I would have dialyzed the patient to correct ca, ph and bicarb without fluid removal if not volume overloaded
u can give ca but it will preciputate with ph. Dialysis would take care of all the problems
To Anonymous…
Yeah, except for the CANCER part.