Antenatal diagnosis and management of urinary abnormalities

Although much time, effort, and money have been expended in the area of fetal surgery and even though considerable unfortunate media publicity has resulted, the actual clinical problem is not one of great magnitude. Currently all those interested in this area agree that consideration of any intrauterine manipulation or surgery should be reserved for a fetus who has bilateral involvement that is progressive, destructive, and associated with oligohydramnios. Except for rare instances, this eliminates all fetuses except those with some type of urethral obstruction. Significant urethral obstruction accounts for approximately 10 per cent of all patients who have a prenatal diagnosis of a urologic abnormality. Of this 10 per cent, some will not be progressive, some will not be destructive, some will not involve both kidneys, and some will not develop oligohydramnios. Some of these patients will be diagnosed early enough in pregnancy to allow termination of the pregnancy if the involvement is significant and if termination is acceptable to the family. Some will be diagnosed late enough in pregnancy so that if the lungs are mature or can be stimulated to mature, early delivery and postnatal management can be elected. Some will have other associated lethal anomalies that can be diagnosed and would preclude any consideration of intrauterine manipulation or therapy. Some will have irreversible renal failure. Occasionally, the mother may refuse any proposed intrauterine therapy. Thus we are probably considering, on a theoretic basis, well under 1 per cent of all fetuses who have a prenatal diagnosis of urologic abnormalities. There may be some unusual situations that justify intrauterine manipulation. One that we encountered involved a fetus with an abdominal mass so large that a cesarean section was deemed necessary (Figs. 12 and 13). Aspiration of the mass just before delivery was performed to allow a vaginal delivery. Another case involved a pregnant woman who developed severe toxemia. The fetus was found to have a solitary renal cyst. Repeated aspirations of the cyst resulted in resolution of the toxemia, which promptly recurred when fluid reaccumulated in the fetal renal cyst. Insertion of a double-universe catheter from the cyst into the amniotic cavity allowed completion of the pregnancy, with the delivery of an otherwise normal fetus without recurrence of the toxemia. A recent report on fetal surgery from the International Fetal Surgery Registry, coauthored by the strongest advocate of intrauterine intervention, reached these conclusions.(ABSTRACT TRUNCATED AT 400 WORDS)