The clinical presentation of a child with CKD may be related to both the underlying diagnosis and complications of CKD. A child with CAKUT may have polyuria, polydipsia, and recurrent urinary tract infections. A child with glomerular disease may have hematuria, proteinuria, edema, and hypertension. Common complications of CKD in children are listed in Table 165-5. Most of these complications are multifactorial in etiology. For example, factors associated with growth failure include poor nutrition, renal osteodystrophy (ROD), metabolic acidosis, hormonal abnormalities, and resistance to growth hormone. Anemia results primarily from a failure to produce adequate erythropoietin and iron deficiency. ROD is usually due to secondary hyperparathyroidism as a result of diminished 1,25-dihydroxyvitamin D production in the kidney, hypocalcemia, and hyperphosphatemia (from decreased renal excretion). If prolonged and/or severe, ROD may eventually lead to rickets and bone deformities. Hypertension and
Table 165-4 Classification of the Stages of Chronic Kidney Disease STAGE GFR (ml/min/ 1.73 m2)* DESCRIPTION >90 Minimal kidney damage 2 60–89 Kidney damage with mild reduction of GFR 3 30–59 Moderate reduction of GFR 4 15–29 Severe reduction of GFR 5 <15 (or dialysis) End-stage renal disease
From National Kidney Foundation Kidney Disease Outcomes Quality Initiative. GFR, Glomerular filtration rate. *GFR ranges apply for children 2 years of age and older.
1. Poor growth Increased caloric intake, treat acidosis, treat renal osteodystrophy, recombinant GH 2. Anemia Erythropoietin, iron supplementation 3.
Renal 1,25-Dihydroxyvitamin D osteodystrophy/ supplementation, calcium secondary supplementation, dietary phosphorous hyperparathyroidism restriction, phosphate binders 4.
Cardiovascular 4a. Hypertension Antihypertensive medications 4b. Left ventricular Volume control hypertrophy 5.
Electrolyte abnormalities Low K diet, furosemide, sodium 5a. Hyperkalemia polystyrene sulfonate 5b. Hyponatremia Sodium supplementation 5c. Metabolic acidosis Alkali replacement
CKD, Chronic kidney disease; GH, growth hormone; K, potassium.
left ventricular hypertrophy are commonly seen cardiovascular complications. Delayed puberty results from altered gonadotropin secretion and feedback patterns. Learning and school performance may also be impaired in CKD.
The management of children with advanced CKD requires a multidisciplinary team of pediatric practitioners. Adequate nutrition should be provided even if this requires dietary supplements and tube feedings. In infants a low-solute formula may be indicated. Unless a child is oliguric, fluid restriction is not necessary. Many children with CAKUT require supplemental salt due to urine sodium wasting. Conversely children with GN tend to retain sodium and may become hypertensive or edematous if given excess salt. Common treatment considerations for other CKD complications are given in Table 165-5.
Measures can be taken to preserve kidney function or slow down the progression of CKD. Hypertension and proteinuria can be treated with ACE inhibitors or angiotensin receptor blockers. Potentially nephrotoxic medications should be avoided when feasible, and medication adjustment for reduced kidney function should be made as appropriate. Protein intake is typically not restricted in pediatric CKD.