Chronic Kidney Disease, Growth, and Nutrition
Core concepts
Chronic kidney disease in children is staged by glomerular filtration rate and albuminuria. Common causes are congenital anomalies of the kidney and urinary tract, glomerular disease, and hereditary disorders. Complications include growth failure, anemia, chronic kidney disease-mineral and bone disorder, metabolic acidosis, hypertension, dyslipidemia, and delayed puberty. Nutrition is central: ensure adequate energy and protein, restrict sodium and phosphate as needed, and monitor growth. Growth hormone therapy is considered for persistent growth failure despite optimized nutrition and metabolic control. Anemia management begins with iron status; erythropoiesis-stimulating agents are used when indicated. CKD-MBD management addresses phosphate, calcium, vitamin D, and parathyroid hormone.
Traps
Do not use serum creatinine alone to estimate GFR; use a pediatric equation such as the Schwartz formula and recognize that creatinine reflects muscle mass. Do not start erythropoietin before correcting iron deficiency. Avoid unchecked phosphate restriction that compromises nutrition. Growth hormone is not a substitute for correcting acidosis, hyperparathyroidism, or malnutrition. Medication dosing often requires adjustment for GFR. Transition to adult care should be planned.
Worked example / rule of thumb
An 8-year-old with CKD has height below the third percentile, elevated phosphate, low calcium, and high PTH. First optimize nutrition, control phosphate with diet and binders, correct acidosis, and ensure vitamin D status; if growth failure persists, consider growth hormone. Rule: in CKD-MBD, control phosphate and PTH while maintaining adequate calcium and nutrition; do not chase a single lab value at the expense of growth.