Physiologic Homeostasis in a Living Human after Pig Kidney Xenotransplantation.

Kidney allotransplantation remains the preferred treatment for end-stage kidney disease, yet donor shortages limit its availability. Xenotransplantation using genetically modified porcine kidneys offers a promising alternative. Here, we report key physiological observations from the first-in-human porcine kidney xenograft over a 51 day postoperative follow-up period. The transplanted kidney maintained essential functions, including waste excretion, electrolyte regulation, and production of concentrated urine, while supporting blood pressure and sodium reabsorption despite reduced activation of the renin-angiotensin-aldosterone system. Sodium retention required diuretic therapy, and mild hypocalcemia and hyperphosphatemia occurred in the setting of pre-existing hypoparathyroidism. Markedly increased urinary uric acid excretion led to hypouricemia without evidence of urate nephropathy. This case demonstrates the ability of a porcine kidney to sustain vital metabolic functions in a living human, while highlighting areas for further research. These findings provide a foundation for optimizing post-transplant care and advancing xenotransplantation as a solution to the critical organ shortage.