Fetal Serum β2-Microglobulin and Postnatal Renal Function in Lower Urinary Tract Obstruction Treated with Vesicoamniotic Shunt.

INTRODUCTION: Although mortality has decreased for fetuses with lower urinary tract obstruction treated with vesicoamniotic shunt (VAS) placement, survivors remain at risk for long-term renal impairment. We tested the association of fetal serum β2-microglobulin (fsβ2M) with postnatal renal function in these patients, hypothesizing that fsβ2M may predict such renal impairment.

MATERIALS AND METHODS: fsβ2M was obtained in patients undergoing VAS placement. The primary outcome was renal function at 3-12 months of life, as assessed by a pediatric nephrologist using medical records. Patients were divided into two groups: (1) 'stable renal function' - probable stable long-term renal function and reasonable growth - and (2) 'loss of renal function' - early loss of renal function and failure to thrive.

RESULTS: Nineteen patients with preoperative fsβ2M received a VAS. Of the 14 survivors, those with fsβ2M ≤5.6 mg/l tended to have stable renal function compared to those with fsβ2M >5.6 mg/l [5/6 (83.3%) vs. 2/8 (25.0%), OR = 15.00, 95% CI 0.70-709.89; p = 0.1026]. Eight of 9 patients followed for >12 months of age had outcomes consistent with the initial renal assessments.

DISCUSSION: Patients with initial fsβ2M >5.6 mg/l and treated with VAS tended to have poor renal outcomes.