PRENATALLY DETECTED POSTERIOR URETHRAL VALVES - QUALITATIVE ASSESSMENT OF 2ND-TRIMESTER SCANS AND PREDICTION OF OUTCOME

Purpose: We attempted to determine if the degree of second trimester d ilatation and/or other qualitative sonographic features of the fetal u rinary tract are predictive of postnatal outcome in male neonates with posterior urethral valves, Materials and Methods: We reviewed ultraso und reports and/or hard copy imaging in 17 eases of posterior urethral valves initially detected on second trimester scans (median gestation 18 weeks, range 15 to 23.5), Ultrasound appearance was categorized ac cording to the pattern and severity of dilatation, cystic change or ec hogenicity of the renal cortex and presence of oligohydramnios. Outcom e was reviewed at a median followup of 5.7 years (range 4.4 to 10). Re sults: Of the 17 cases there was a poor outcome in 10, including death in 4 and chronic renal failure in 6. Seven patients were alive and we ll with normal renal function at followup. The prognosis in cases of m oderate or severe upper tract dilatation was poor, Of the 9 patients w ith marked prenatal hydroureteronephrosis 8 (89%) were dead or had chr onic renal failure at followup, In contrast, only 2 of the 8 patients (25%) with mild upper tract dilatation or dilatation limited to the bl adder had chronic renal failure at review (p = 0.05). Three cases of p renatal renal parenchymal change and 3 of subsequent oligohydramnios h ad a poor outcome postnatally. Conclusions: The prognosis for boys wit h prenatally detected posterior urethral valves is closely associated with qualitative aspects of second trimester scan findings. This infor mation may be of clinical value in the prenatal counseling of parents.