A Case of Hypokalemia Caused by Left Native Renal Artery Stenosis in a Kidney Transplant Recipient.

A 39-year-old woman with end-stage renal failure of unknown origin was on peritoneal dialysis for 10 years. One year ago, she underwent ABO-incompatible living-donor kidney transplantation from her husband. After the kidney transplantation, her serum creatinine level remained around 0.7 mg/dL, but her serum potassium level remained low at around 3.5 mEq/L despite potassium supplementation and spironolactone. The patient's plasma renin activity (PRA) and plasma aldosterone concentration (PAC) were markedly elevated (20 ng/mL/h and 868 pg/mL, respectively). A CT angiogram of the abdomen performed 1 year previously suggested stenosis of the left native renal artery, which was considered responsible for the hypokalemia. Renal venous sampling was done on both the native kidneys and the transplanted kidney. Since renin secretion from the left native kidney was significantly elevated, a laparoscopic left nephrectomy was performed. Postoperatively, the renin-angiotensin-aldosterone system was markedly improved (PRA: 6.4 ng/mL/h, PAC: 147.3 pg/mL), and the serum potassium levels also improved. Pathological examination of the removed kidney showed many atubular glomeruli and hyperplasia of the juxtaglomerular apparatus (JGA) in residual glomeruli. In addition, renin staining showed strong positivity in the JGA of these glomeruli. Here, we report a case of hypokalemia caused by left native renal artery stenosis in a kidney transplant recipient. This valuable case study provides histological confirmation of maintained renin secretion in an abandoned native kidney after kidney transplantation.

Long-term Clinical Course after Living Kidney Donation by a Patient with Gitelman Syndrome Harboring a Compound Heterozygous Mutation of the SLC12A3 Gene.

The eligibility for kidney donation and long-term post-donation renal prognosis of patients with Gitelman syndrome (GS) are unknown. We herein report a 44-year-old woman with GS who donated her kidney for transplant. A gene sequence analysis revealed compound heterozygous mutations of T180K and L858H in the SLC12A3 gene. Since transplantation, the renal function and serum potassium and magnesium levels of the donor and recipient have remained stable for seven years with careful monitoring and supplementation. Patients with asymptomatic GS who have no complications can be considered eligible to donate their kidney for transplant with proper monitoring after transplantation.