Association of age with risk of first and subsequent allograft failure and mortality among young kidney transplant recipients in the USA - a retrospective cohort study.

Adolescent age may be a high-risk period for kidney allograft failure. However, the knowledge on this topic is limited mostly to the first transplant. Among 20 960 patients aged ≤21 years at the first kidney transplantation from the US Renal Data System, we evaluated the association of age at the first kidney transplant with risk for the first and subsequent graft failures (1st, 2nd, and 3rd) using the conditional risk set model for recurrent time-to-event data. The median age was 15 (interquartile range: 9-18) years, and 18% received transplants twice or more during a median follow-up of 9.7 years. The risk for graft failures was highest in 16 to <18 years old with an adjusted hazard ratio (aHR) of 1.93 (95% CI, 1.73-2.15; reference: <3 years). When separately analyzed, the highest risk was observed in 17, 19, and 21 years old for the first, second, and third transplant, respectively. Those 16 to <18 years were also strongly associated with the highest risk for death after returning to dialysis (aHR, 4.01; 95% CI, 2.82-5.71). Adolescent recipients remain at high risk for allograft failure for a long time, which may result in high mortality risk, even though they surpass this high-risk period soon after the first transplant.

Ureteric and urethral stenosis: a complication of BK virus infection in a pediatric renal transplant patient.

Viral infections remain an Achilles heel in solid organ transplant. In recent years, incidence of BK virus infection in the kidney transplant population is on rise. BK virus is known to cause severe renal dysfunction, ureteric stenosis, and hemorrhagic cystitis in renal transplant patients. Most of the reviews and prospective studies on BKV nephropathy pertain to the adult population. Although ureteral stenosis is known to occur in BK infection, urethral stenosis is not being reported in the literature. In this report, we describe a case of BKV nephropathy in a 16-yr-old male presenting with ureteric and urethral stenosis. To our knowledge this is the first case report of its kind in a pediatric transplant population.

Initial comparison of robotic-assisted laparoscopic versus open pyeloplasty in children.

OBJECTIVES: To compare the initial results of robotic-assisted laparoscopic versus open pyeloplasty in children with ureteropelvic junction obstruction. METHODS: From June 2002 to July 2004, 8 pediatric patients underwent robotic-assisted laparoscopic pyeloplasty and were matched by age group with patients undergoing conventional open pyeloplasty. The mean age was 11.5 years (range 6.4 to 16.5) in the robotic-assisted group and 9.8 years (range 6.0 to 15.6) in the open group. A four-port transperitoneal technique was used to perform the Anderson-Hynes pyeloplasty with the da Vinci Surgical System. RESULTS: The mean operative time and estimated blood loss was 363 minutes (range 255 to 522) and 13.1 mL (range 5 to 25) in the robotic-assisted group versus 248 minutes (range 144 to 375) and 53.8 mL (range 5 to 200) in the open group, respectively. The mean length of hospitalization and pain medication use was 2.4 days (range 1 to 5) and 7.4 mg morphine (range 0 to 23) in the robotic-assisted group compared with 3.3 days (range 1 to 8) and 22.0 mg morphine (range 0 to 100) in the open group, respectively. At a mean follow-up of 14.7 months (range 2 to 24), all robotic procedures were successful as determined by subjective data using pain scales and radiologic data. CONCLUSIONS: Robotic-assisted laparoscopic pyeloplasty appears to decrease the length of hospitalization and use of pain medication, but has a longer operative time. Additional clinical experience is required to determine the long-term efficacy of this method.

Acute hemodialysis for hyperammonemia in small neonates.

Neonatal metabolic emergencies require a multidisciplinary team approach for supportive management that has increasingly come to feature renal replacement therapies in addition to nutritional support, the use of pharmaceutical agents, and testing to guide management and provide a definitive diagnosis. An increased appreciation for the mechanisms involved in ammonia neurotoxicity has placed greater emphasis on the need for its rapid yet safe resolution to optimize long-term prognosis. We examined our experience of intermittent hemodialysis (HD) and considered (1) the feasibility of HD in low-weight neonates, (2) the rate of decrease in ammonia, (3) complications during HD in small neonates weighing <4 kg presenting at University Children's Hospital between 1999 and 2002. Additionally, we review the current cellular and molecular mechanism of ammonia-induced brain injury. All patients tolerated intermittent HD and all required pressor agents. We primed all our patients with 20 U/kg of heparin and there was no subsequent need for further heparinization. We also noted that hemodynamic instability persisted during the first 1-2 h of the procedure and improved thereafter, as indicated by a decreased need for pressor agents. All neonates are alive to date. In conclusion, HD remains an effective and practical mode of renal replacement therapy having readily managed complications in preterm neonates weighing <4 kg with metabolic disorders.