Nephrology
Clinical discussions on kidney disease management, dialysis, transplantation, and electrolyte disorders.
Recent Discussions
Do you periodically check a urine culture for patients without dysuria but who have a history of struvite kidney stones and urinary tract infections with urease producing organisms?
Struvite nephrolithiasis is caused by a high urine pH (usually>7.0). Typically, a urine this alkaline requires urinary infection with a bacterium that produces urease, (Proteus, Providencia, Klebsiella) which in turn splits naturally occurring urea into ammonium, driving the pH to supraphysiologic l...
Do you start patients on a B complex multivitamin if they are on CRRT and have not previous been on renal replacement therapy?
This is a good question. I personally don’t routinely recommend Vitamin supplements for patients on CRRT, but wouldn’t argue with someone who does. It is known that critically ill patients, which includes most CRRT patients, often have deficiencies in micronutrients, including water-soluble vitamins...
Do you routinely perform in-office urine microscopy for your patients with recurrent nephrolithiasis?
Yes and no. We have a dedicated laboratory at Mayo Clinic that specializes in urinalysis and is expert in recognizing crystals. I do not do office microscopy myself. I think it is important for my stone patients to have a urinalysis when I see them. I am looking for hematuria suggesting surgical sto...
What are some considerations to make when managing patients with recurrent nephrolithiasis who are found to have nephrocalcinosis on imaging?
Nephrocalcinosis is generally defined as calcification of the renal parenchyma, especially the medulla and papillary tips, as opposed to nephrolithiasis which refers to calcification in the urinary space. The two often coexist. Nephrocalcinosis, and its accompanying nephrolithiasis, are typically pr...
What is your preferred therapy to raise urinary citrate in a patient with recurrent calcium based stone disease and hypocitraturia?
I prefer potassium citrate tablets. For those who have trouble swallowing tablets, it also comes in liquid form. There used to be a powder packet that you could tear open and mix in liquid, but it is my understanding that is no longer available. These products require a prescription. For those on a ...
Do you avoid ESAs in patients with anemia and chronic kidney disease who also have Factor V Leiden?
I personally do not. I think it is better to get the hemoglobin in the 10-11 g/dL range and avoid having to give blood transfusions potentially than the slightly increased risk of hypercoagulability.
What is your approach to determining the need for continued isolation in the dialysis unit for an ESKD patient who had a positive hepatitis B surface antigen one year ago but who now has a negative HbsAg in the absence of treatment?
I have not encountered this situation before. Assuming that both checks are accurate and not the result of vaccination, then I would continue to isolate for another 6 months, repeat Hep BsAg and viral load. If still negative would take off isolation.
Do you consider hyperuricemia as a potential etiology of an anion gap metabolic acidosis in patients with elevated uric acid levels and no other readily explainable causes of acidosis?
Urate has a molecular weight of ~166 mg/mmole and the valence of the anion is -1. Hence, let us say we have severe hyperuricemia with 16 mg/dl. That will provide an "anion gape" of only 1! So, by itself, urate cannot increase the anion gap. Could hyperuricemia be a "biomarker" of other causes of met...
What is your approach to safely performing hemodialysis in a patient with a fistula who is hospitalized for altered mental status and unable to remain still?
First, I would try to delay performing dialysis if possible and give the patient a chance to be more alert. Second, if there is a way to perform dialysis safely through meds or very close supervision, then I would try to use the fistula for dialysis. If the above is not possible, then the patient wo...
What considerations do you take when managing a patient with end stage kidney disease on peritoneal dialysis who is planning on undergoing PEG tube placement?
This is a somewhat difficult question to address, as there is more opinion and conventional “wisdom” than there is data. Let me begin with the “easy” part: notwithstanding reports of caregivers confusing the PD catheter for the PEG tube and instilling enteral feeding solutions intraperitoneally, pla...