Correlation of renal volume to renal function and blood pressures in low birth weight children

Background Disruption of nephrogenesis in low birth weight (LBW) infant leads to decreases in nephron number and renal volume, resulting in renal hyperfunction and eventually, hypertension. Objective To assess for a possible correlation of renal volume to renal function and blood pressures in low birth weight children aged 7 -8 years. Methods We conducted a retrospective cohort study on children aged 7-8 years in Manado, who were born LBW or n ormal birth weight (NBW). Renal function was assessed by measuring blood cyctatin-C level while renal volume was determined using ultrasound measurements of renal length x width x thickness (cm3). Ttest was used to compare renal volume and cystatin-C levels in LBW children to NBW children. Pearson's correlation test was used to assess the relationship of renal volume to renal function and blood pressure in low birth weight children. Results Subjects were 48 LBW and 48 NBW children. Mean renal volumes were 7 8.28 (SD 7 .96) cm3 in the LBW group and 103.68 (SD 12.52) cm3 in the NBW group (P< 0.01). The mean cystatin-C levels, as a measure of renal function, were 0.81 (SD 0.07) mg/Lin the LBW group and in 0.73 (SD 0.06) mg/Lin the NBW group (P< 0.01). There was no correlation between renal volume and cystatin-C level (r=-0.169; P>0,05) as well as between renal volume and systolic (r=-0.07, P>0.05) and dias tolic blood pressure (r=-0.123, P>0.05). Conclusion Mean renal volume is lower in the LBW group than in the NBW group, but is not correlated to decreased renal function or blood pressures