Low Birth Weight is Associated with More Severe Course of Steroid-Sensitive Nephrotic Syndrome in Children, Multicentric Study.

Background: Several previous studies have reported a more severe course of nephrotic syndrome in children with low birth weight.

Patients: Cohort of 223 children with idiopathic nephrotic syndrome.

Methods: We aimed to investigate the association between course of nephrotic syndrome and low birth weight. Data from seven paediatric nephrology centres were used.

Results: Children with low birth weight had 3.84 times higher odds for a more severe course of steroid-sensitive nephrotic syndrome (95% CI 1.20-17.22, P=0.041), and those with low birth weight and remission after 7 days had much higher odds for a more severe course of disease (OR 8.7). Low birth weight children had a longer time to remission (median 12 vs. 10 days, P=0.03). They had a higher need for steroid-sparing agents (OR for the same sex=3.26 [95% CI 1.17-11.62, P=0.039]), and the odds were even higher in females with low birth weight (OR 6.81). There was no evidence of an association either between low birth weight and focal segmental glomerulosclerosis or between low birth weight and steroid-resistant nephrotic syndrome.

Discussion: We conducted the first multicentric study confirming the worse outcomes of children with NS and LBW and we found additional risk factors.

Conclusions: Low birth weight is associated with a more severe course of steroid-sensitive nephrotic syndrome, while being female and achieving remission after 7 days are additional risk factors.