Nephrology
Clinical discussions on kidney disease management, dialysis, transplantation, and electrolyte disorders.
Recent Discussions
What is your approach to differentiating diabetes insipidus from primary polydipsia in the outpatient setting?
I usually do overnight dehydration tests for 12 hours and if fasting AM urine osmolality is >600 DI is less likely. If urine osmolality is low with high serum sodium it indicates DI, whereas with primary polydipsia the serum sodium is low with low urine osmolality.
Are there any varying treatment considerations to make when managing patients with carbonate apatite versus hydroxyapatite kidney stones?
Both of these stone types require a relatively alkaline urine to crystallize. Not surprisingly, they are often found in combination within the same stone. My diagnostic and treatment considerations do not depend on which mineral composition predominates. Stephen B Erickson, MD
Do you make any changes to surveillance imaging frequency, 24 hour urine stone risk collection frequency, and stone preventative medication approaches for patients with recurrent nephrolithiasis who become pregnant?
Pregnancy is a lithogenic state. Stone passages peak in the second trimester. I avoid imaging that involves radiation. I monitor with ultrasound. I prefer to withdraw prescription medication and manage stone disease with diet and fluid therapy. Certainly, there are exceptions to this rule. Encouragi...
When would you administer the next maintenance dose of rituximab in a patient with ANCA glomerulonephritis who last received an infusion six months ago and has low immunoglobulin levels and an undetectable CD-19 cell count?
If an ANCA vasculitis patient is in remission and has no infections, I usually in clinical practice do not check Immunoglobulin levels or CD19/20 levels either. They should only be done in patients with recurrent sinus infections or Pneumonia. If the patient with recurrent infections has low Immunog...
How do you approach a patient with biochemical evidence of primary hyperparathyroidism, but normal parathyroid scan?
Negative sestamibi scans are not unusual in patients with primary hyperparathyroidism. Other imaging tests may be negative also. If the patient has biochemical evidence of the problem and has even mild complications referral to an experienced parathyroid surgeon would be warranted. Alternatively, ci...
What is your fluid intake target for patients with nephrocalcinosis and no history of kidney stones?
Nephrocalcinosis represents calcification of the renal parenchyma as opposed to nephrolithiasis that represents classification in the urinary space. The two conditions occasionally coexist, such as a medullary sponge kidney, distal renal, tubular, acidosis or primary hyperparathyroidism. For patient...
Do you take any different approaches for patients with end stage kidney disease who are about to be initiated on intermittent hemodialysis and have residual renal function?
The main consideration I have in these patients is making sure I do not try to remove extra fluid; if there is enough residual renal function to provide at least 1,000 ml/day of urine output, most likely this patient will not require net ultrafiltration, only dialysis. By paying attention to this on...
What is your approach to patients with chronic kidney disease who are found to have pelviectasis without hydronephrosis on renal ultrasound imaging?
Good question. I would involve urology early on. I would get more history as to other signs/symptoms of urinary obstruction (nocturia, BPH symptoms, history of retroperitoneal fibrosis). Then, consider a Lasix urogram.
Do you recommend performing surveillance kidney allograft biopsies in your asymptomatic kidney transplant recipients?
In general, I am a believer in management or surveillance biopsies. However, I also think there should be low threshold to forego the biopsy should it put the patient at increased risk, such as anticoagulation or intraperitoneal kidney. The other consideration is what is your plan for treating, or n...
Do you recommend patients consume dairy products over taking calcium carbonate with meals if they have recurrent calcium based nephrolithiasis and persistent hyperoxaluria?
I generally consider the decision between dairy and calcium tablets in the context of other medical conditions. For instance, if the patient has surgical or medical short gut syndrome as a cause of hyperoxaluria, I favor using calcium tablets to help compensate for the enteric loss of bicarbonate in...