The malnutrition and inflammation axis in pediatric patients with chronic kidney disease

Malnutrition and inflammation are closely linked in adult chronic kidney disease (CKD) patients and are both related to poor outcome, but data on pediatric patients are lacking. To describe the prevalence of inflammation, evaluate nutritional status, their correlation to each other, and their possible determinants in pediatric patients with CKD in predialysis, on hemodialysis (HD), and peritoneal dialysis (PD) who were submitted to demographic, nutritional, and inflammatory evaluations. Patients' nutritional status was evaluated according to anthropometric parameters and body composition assessed by measurements of skinfold thickness and bioelectrical impedance. Inflammation was assessed by measurement of highly sensitive C-reactive protein (CRP), ferritin, and albumin. Patients with CRP > 1 mg/l were considered inflamed. Sixty-four pediatric patients (mean age 9 +/- 4 years-, 40% on HD, 22% on PD, and 38% predialysis) were studied. Mean CRP concentration was 3.4 +/- 6.5 mg/l (median 0.78 mg/l, range 0.78-33.4 mg/l), and 41% presented CRP levels above 1 mg/l. Mean ferritin was 148 +/- 197 mg/dl and was above the normal reference values in 28% of patients. On the other hand, mean albumin was 3.9 +/- 0.5 mg/dl, below reference value in only 13% of patients. A larger proportion of HD patients (52%) were inflamed compared with those on PD (31%; p < 0.05). Malnutrition prevalence varied from 5% to 65% according to the method used. While inflamed patients presented lower serum bicarbonate and were on HD for a longer time, there were no consistent associations between malnutrition and inflammation. Inflammation is highly prevalent in the pediatric CKD population and was not consistently related to malnutrition. Other risk factors linked to high mortality and morbidity (acidosis and longer time on dialysis) were associated with inflammation. Prospective studies will need to analyze the predictive value of inflammation and malnutrition markers in the pediatric CKD population.