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

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.

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.

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.

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