Nephrology
Clinical discussions on kidney disease management, dialysis, transplantation, and electrolyte disorders.
Recent Discussions
Do you advise your patients with cystinuria to perform home urine pH testing?
Definitely! Keeping urine pH above 7.0 is one of the most effective ways of preventing cystine crystallization. pH testing strips can be purchased cheaply on the Internet or in “big box” stores. (Pharmacies are much more expensive). I suggest testing four times daily and adjusting the urinary alkali...
For a patient with idiopathic hypercalciuria and a history of calcium kidney stones who has not normalized 24-hr urine calcium level on thiazide diuretic, is there evidence for targeting a certain urine calcium level for decreased future risk of nephrolithiasis and osteoporosis?
A good question, and the answer depends on your definition of a "normal" urine calcium level. If you use the standard definition of abnormal, the upper 5 percentile, depending on your laboratory, you will get values for upper normal calciuria in the 250-300 mg per day. However, approximately 10% of ...
Do you use PTH levels to help differentiate CKD from AKI in patients who are being evaluated for an elevated creatinine level and who lack long term lab data?
Distinguishing between AKI and CKD in the absence of previous labs can sometimes be challenging. Although PTH levels tend to be higher in CKD than AKI patients, PTH levels can increase quickly in AKI, and a substantial portion (25-50%) of AKI patients will have a high PTH level. So, while it may be ...
Is there a BUN threshold for which you recommend dialysis prior to a kidney biopsy to avoid risk for bleeding?
Probably not HD but I might give DDAVP.
Do you recommend parathyroid imaging testing for patients with recurrent nephrolithiasis who are incidentally found to have an elevated PTH but who do not have hypercalciuria, hypercalcemia, hypovitaminosis D, or chronic kidney disease?
Yes, but with caveats. The “yes” is because hyperparathyroidism is a surgically curable disease if done by an experienced parathyroid surgeon. The caveat is if previous stone analyses have not shown a substantial calcium phosphate component, the stone formation may be due to other causes and unaffec...
Do you recommend obtaining a DEXA scan for patients with recurrent nephrolithiasis and hypercalciuria of unknown etiology?
I think this is an important question. I agree with Dr. @Dr. First Last. In my practice, if the patient is female, especially peri- or postmenopausal, I generally recommend a DEXA scan. If bone density is borderline or low, I typically refer the patient to an endocrinologist in our Bone Clinic for c...
What are your recommendations for stone prevention for patients with recurrent calcium based nephrolithiasis who consume well water with a high calcium concentration?
Drink lots of it! Seriously, studies done long ago, looking at the geography of stone formers did not correlate with water hardness (mineral content), but rather with average temperature, the incidence of stone passage being higher in the southern parts of the United States. The amount of calcium co...
How do you determine which patients with ANCA associated vasculitis may be good candidates for reduced dose glucocorticoid tapering?
This is an important question. Currently there are several groups of patients that benefit from reduced dose glucocorticoids: The largest group are patients who are receiving avacopan for remission induction. The ADVOCATE trial demonstrated that avacopan can markedly reduce the dose of glucocorticoi...
Are there any special considerations to take into account when managing patients with recurrent nephrolithiasis who are found to have a horseshoe kidney?
Interesting question! Horseshoe kidneys are particularly susceptible to stones, primarily in the lower poles. Stones are typically composed of calcium oxalate. Renal embryology was a neglected topic during my medical education. The prometanephros are located near the fetal cervical spine. They subse...
What is your approach to immunosuppression in patients with preserved kidney function who are found to have nephrotic syndrome of unknown etiology and cannot safely undergo a kidney biopsy?
This is a difficult scenario. Would definitely try to get a biopsy at a Higher level of care perhaps by Interventional Nephrology. Would obtain a comprehensive laboratory workup including kidney function, serum albumin level, random and 24-hour urine collection for albuminuria and proteinuria, Hepat...