How often do you check renal function panels for patients with recurrent nephrolithiasis?

Interestingly, most patients with recurrent kidney stones have normal or near normal GFR. I check them annually when I do imaging and 24-hour urine supersaturations looking for metabolically active stone disease.

For those patients with decreased GFR, I recheck them at the same frequency, I would check non-stone formers with similar GFRs.

For stone formers experiencing ureteral colic, I check creatinine or cystatin C immediately, in addition to imaging, to assess the degree of obstruction and hence the urgency for surgical intervention.

Stephen B. Erickson, MD