Prescribing Peritoneal Dialysis in Children

Initiation of Dialysis in Children

Indications for initiating renal replacement therapy in children are based on clinical, biochemical, and psychosocial parameters, which should be individualized for each patient. These parameters may vary based on the child’s age, as both the biochemical norms and the developmental needs of the child can change, as well as their primary etiology of chronic kidney disease (CKD). An infant with renal dysplasia and a serum phosphorus level of 6 mg/dL is desirable, but if they are not gaining weight, it can be very worrisome. Whereas an adolescent with lupus nephritis would benefit from lower phosphorus levels, while weight gain may put them at certain cardiovascular risk. Inappropriate nutrition in children may allow for “normal” laboratory results (e.g., potassium, urea) and manifest not with weight loss but with growth failure. Therefore, a regular global assessment of the child with advanced CKD, with particular attention to growth and development, is warranted.

Objective criteria for initiation of dialysis in children have been iterated in the most recent Kidney Diseases Outcomes Quality Initiative (KDOQI) guidelines on PD adequacy. Those recommendations are that dialysis initiation should be considered in the pediatric patient when their estimated glomerular filtration rate (GFR) is ≤ 15 mL/min/1.73 m ² and recommended in the pediatric patient with a GFR ≤ 8 mL/min/1.73 m ² . European guidelines have shared this objective threshold of considering dialysis if the GFR is ≤ 15 mL/min/1.73 m ² . Recent reports have shown that the percentage of pediatric patients initiating dialysis at higher estimated GFR (> 10) had increased 2.5-fold in the United States over the past two decades, from 16.5% in 1995 to 40.8% in 2015. A comparison of those initiating dialysis at a higher GFR (> 10) to those at a lower GFR (< 10) revealed a 24% higher risk of death for those initiating at the higher GFR cut-off after censoring patients upon being transplanted. However, there was not a statistically significant difference in mortality risk seen among PD patients who initiated dialysis at the higher GFR cut-off compared to the lower GFR. A similar study performed in Europe comparing children who initiated dialysis at a higher estimated GFR (> 8) found no clinically relevant benefit in terms of overall survival, growth, or access to transplantation, but again no separate distinction was made for those initiating PD at the different GFR thresholds. Therefore, there does not seem to be an absolute threshold of GFR in children at which dialysis, or PD, needs to be initiated, although experts would suggest consideration once estimated GFR is < 10 mL/min/1.73 m ² .

However, both North American and European guidelines recommend that the pediatric patient’s clinical course takes precedence over any estimate of kidney function. Initiation of dialysis should be considered at higher GFR levels if the patient has findings or symptoms that are refractory to medication or dietary management. Similarly, dialysis does not have to be automatically started at lower GFR levels if the patient has normal lab values and is otherwise asymptomatic. Metabolic disturbances seen in pediatric patients include hyperkalemia, hyperphosphatemia, metabolic acidosis, and azotemia, although normal serum values for potassium are slightly higher for infants and normal values for phosphorus are higher for preadolescents. The clinical findings may include fluid overload, hypertension, malnutrition, and growth failure. As there is a preponderance of nonglomerular disorders causing ESRD in children, urine output may be preserved, while fluid overload and hypertension, which is almost universally seen in adults with ESRD, may not even occur in some pediatric patients. Growth failure in children can be particularly difficult to detect if not cognizant of its findings. It may manifest with a static weight during a period when a child would normally be gaining or a decrease in height velocity, a measure unique to children which varies greatly by growth stage. Other symptoms of ESRD in children may include anorexia, nausea, vomiting, and decreased energy levels. Frank’s neurologic symptoms of uremia are rare in children but may present with more subtlety, such as decreased levels of concentration and attentiveness. Diminished school performance or decreased daily activity levels should be screened for and considered as pertinent findings of disease management.

Similar to KDOQI recommendations in adults with CKD, patient and/or caregiver education about renal replacement therapy options should occur as the patient advances into stage 4 CKD. The timing of education should ideally give the patient and caregivers ample time to decide upon a dialysis modality, if needed, and for any advanced access planning. This should include anticipatory planning for other surgeries that may be needed in the pediatric patient, such as feeding tube placement, native nephrectomy, or major urologic procedures. The education should be conducted by a multidisciplinary team, including dialysis nurses, social workers, and dieticians, all of whom should also assess the patient and caregiver’s comprehension of the risks, benefits, and demands of the available treatment options. The education should present nonbiased information on hemodialysis (HD), PD, and transplant to the patient and family, but unavoidably may be influenced by the experiences of the multidisciplinary team.