[Kidney transplantation in low-age, low-weight children: A report of two cases].

Kidney transplantation is widely recognized as the optimal treatment for children with end-stage renal disease (ESRD), offering significant improvements in growth, development, and long-term quality of life compared with prolonged dialysis. However, kidney transplantation in low-age (< 5 years old) and low-weight (< 15 kg) children presents significant clinical challenges due to their delicate vascular structures, limited surgical space, and complex perioperative management. This report presents two cases of kidney transplantation in low-age, low-weight children performed at Peking University People' s Hospital. Case 1: a 2-year-3-month-old boy (8.8 kg), presenting a preoperative serum creatinine of 248 μmol/L post-dialysis and the estimated glomerular filtration rates (eGFR) of 35.17 mL/(min·1.73 m). Case 2: a 3-year-8-month-old girl (11.25 kg), presenting a preoperative creatinine of 281 μmol/L post-dialysis and the eGFR of 22.63 mL/(min·1.73 m). Both recipients underwent transplantation the extraperitoneal approach, with end-to-side anastomosis of the donor renal artery and vein to the recipient' s common iliac artery and vein, respectively. The ureters were anastomosed to the bladder using the tunnel technique, and double-J stents were placed intraoperatively. The surgeries were uneventful, and both patients exhibited rapid recovery of renal function. Postoperatively, serum creatinine levels decreased to 26 μmol/L (Case 1) and 39 μmol/L (Case 2) by the third day, with the eGFR reaching 245.23 mL/(min·1.73 m) and 164.12 mL/(min·1.73 m), respectively. No complications, such as vascular thrombosis, ureteral stenosis, or abdominal compartment syndrome were observed during follow-up. A comprehensive literature review was conducted to contextualize these cases within global advancements in pediatric renal transplantation. Current evidence highlights the growing adoption of kidney transplantation for low-age, low-weight children, though debates persist regarding optimal surgical strategies (specifically, the intraperitoneal versus extraperitoneal approaches). This case report underscores the feasibility of the extraperitoneal approach in overcoming anatomical limitations of low-weight pediatric recipients, with distinct advantages including reduced gastrointestinal complications and enhanced accessibility for post-operative ultrasound monitoring. Furthermore, mean arterial pressure (MAP) and central venous pressure (CVP) were systematically monitored intraoperatively to ensure optimal renal blood perfusion and graft viability. Our single-center experience provides valuable insights into surgical strategy selection and perioperative management for this high-risk population. Nevertheless, larger multicenter studies are warranted to validate long-term outcomes and refine standardized protocols.