Body composition in children on peritoneal dialysis.

Dual-energy X-ray absorptiometry (DEXA) can be used to evaluate total-body bone mineral content (BMC), bone mineral density (BMD), fat-free mass (FFM), and fat body mass (FBM), which are all frequently affected in patients (PD) on peritoneal dialysis. We used DEXA to evaluate body composition in children on PD and to establish whether relationships existed with nutrition status, dialytic parameters, and biochemical data. We evaluated 20 PD patients (12 boys, 8 girls). The mean age of the patients was 5.84 years (range: 0.16- 14.66 years). We carried out DEXA, anthropometry (weight/age, height/age, and body mass index), and measurements of dietary intake (protein, energy, calcium, and phosphorus), nitrogen balance (NB), dialysis dose (Kt/V), peritoneal equilibrium test (PET), and plasma calcium, phosphorus, and bicarbonate at months 1 and 6 of the study. Energy intake was prescribed according to the United States Recommended Dietary Allowances, and Kt/V and daily protein intake (DPI) according to the Dialysis Outcomes Quality Initiative (DOQI) guidelines. In the patients, BMD increased to 0.769 +/- 0.174 g/ cm2 from 0.747 +/- 0.166 g/cm2 (p < 0.05), and BMC increased to 680.3 +/- 666.1 g from 632.6 +/- 597.5 g (p < 0.01). The mean BMD Z score for patients older than 4 years (n = 11) was -0.69 at month 1, with a significant increase to -0.35 at month 6. The FBM and FFM increased, but without reaching statistical significance. At months 1 and 6, the DPI was 144.3% and 129.9% respectively (p = nonsignificant) and showed a negative correlation with BMD, BMC, and FFM (p < 0.05). Comparing DPI to plasma bicarbonate showed a negative correlation at month 1 (p < 0.05). Negative correlations were also found between NB and the parameters BMD, FBM, and FFM (p < 0.05). be content All patients showed a positive NB. No correlation was found between DEXA and anthropometric measurements, energy intake, serum calcium, serum phosphorus, or Kt/V Dialysate-to-plasma creatinine from the PET showed a negative correlation with BMD and FFM (p < 0.05). In terms of positive NB and controlled Kt/V we observed an increase in bone mineralization within the 6 months offollow-up. A high protein intake seems to negatively affect acid-base status, bone mineralization, and FFM.