Search

Background: The success of a chronic hemodialysis program depends on a good vascular access., Aim: To evaluate the experience with vascular accesses for chronic hemodialysis in pediatric patients., Patients and Methods: One hundred fifty-one vascular accesses used in 60 pediatric patients (33 female) coming from 2 hemodialysis (HD) centers were analyzed., Results: The average age of admission to the hemodialysis program was 10 years old (range 1.8-15). Forty percent of accesses were internal arterio-venous fistulae (AVF), 58% were central venous catheters and 2% were grafts. Twenty four patients required a central venous catheter from the beginning since they required immediate dialysis. Twenty patients began dialysis with a permeable AVF and never required another vascular access. Eight small children used a central catheter as the only vascular access and 32 patients required both types of vascular accesses. Eighty-seven catheters were used in 34 patients, of which 77 were temporary and 10 permanent. Seventeen patients needed only one catheter and one girl required 15 catheters. The average life span for AVF was 524 days (20-1277), for temporary catheters 34 days (1-76) and for permanent catheters 73 days (9-147). Two years survival of AVF was 95%. One month survival for subclavian and jugular catheters was 50%. Fifty-six percent of AVF had no complications, 12 failed due to insufficient flow and 24% had a complication. Of the 87 catheters placed, 75% had complications and 22 were electively removed., Conclusions: Arteriovenous fistula is the vascular access of choice for hemodialysis in pediatric patients. Central venous catheters can become an essential access, specially in small children.

The clinical features of eight patients, four females, aged 4 to 15 years under chronic hemodialysis for terminal renal failure (creatinine clearance 10 ml.min.1,73 m2 or less) are reported. Initial diseases were Alport syndrome, systemic lupus erythematosus, chronic glomerulonephritis (n = 2), bilateral polycystic kidney, prune belly syndrome and reflux nephropathy (n = 2). Distal vascular approach by means of arteriovenous fistulas was preferred for these patients and the kinetic urea model was used to evaluate the performance of the procedure. Patients required nine to twelve hours of hemodialysis per week for optimal results. Mean weight decreases of 1 to 3 kg and reductions in blood urea nitrogen and serum potassium of 40 mg.dl and 2,5 mEq.1, respectively, were observed. The main complications of hemodialysis were the disequilibrium syndrome, infections at the site of insertion of the arteriovenous fistulae and congestive heart failure. Three patients were submitted to renal transplantation with live donors homografts: one died and the other two remain alive but under chronic hemodialysis. Five children are attending school regularly, and two of them are waiting a kidney donor for transplantation. Despite encouraging results chronic hemodialysis in children constitutes only primary supportive therapy prior to renal transplantation.

In 50 children with hematuria or urolithiasis and idiopathic hypercalciuria, and in 15 control children, urinary calcium/creatinine concentration rates were measured after fasting and after calcium loading. Patients were classified into two groups depending on the results of an orally administered calcium loading test. Children were considered to have absorptive hypercalciuria (42%) when they had low fasting urinary calcium/creatinine concentration ratio (less than 0.21), and a large increase of this index after calcium administration (greater than 0.28). Patients were labeled as renal hypercalciuria (32%) if they had high fasting urinary calcium/creatinine concentration ratio (greater than 0.21), and variable increases of it after calcium overload. A third group of children (26%), were not classifiable by means of this test. Our data support the contention that this simple ambulatory test is very useful in the diagnostic workup of idiopathic hypercalciuria.