Eur. J. Obstet. Gynecol. Reprod. Biol., 23 (1986) 107-110 Elsevier
Puncture of unilateral renal cyst in utero M. Temmerman
I, S. Levi 4, M. Verboven
2, M. Delree 3 and J.J. Amy ’
Departments of’ Gynaecologv, Andrology and Obstetrics, 2 Paediatrics and 3 Radiology, Academisch Ziekenhuis, Vrije Universiteit Brussel, Brussels, and 4 Department of Obstetrics and Gynaecolow, Unit of Ultrasonography, University Hospital Brugmann, Universite Libre de Bruxelles, Brussels, Belgium Accepted
24 June 1986
Summary Although most authors do not recommend prenatal puncture of a unilateral single cystic renal mass, in case the contralateral kidney is normal and there is sufficient amniotic fluid, this case report shows that the procedure, which can be done very carefully under ultrasonic guidance, can be helpful in establishing the presumed diagnosis. renal cyst; prenatal
Case report A healthy 26yr-old gravida 2, para 1, was referred for routine fetal sonography at 26 wk of pregnancy. Her past medical history was unremarkable, and her previous pregnancy uncomplicated. Sonography revealed a single living male fetus, in cephalic presentation, of approximately 26 wk gestational age. A unilocular cystic mass was detected in the abdomen of the fetus, in the area of the left kidney. No normal renal tissue was identified on the left side. The volume of the cyst was estimated at 80 ml. The right kidney appeared normal. There was no evidence of ureteric dilatation or bladder distension. There was a normal amount of amniotic fluid. The placenta was anteriorly located. The normal amniotic fluid volume indicated good function of the right kidney, so that no intervention was advised. A repeat scan two weeks later done by the same observer - confirmed these findings: fetal growth was ap-
Correspondence address: M. Temmerman, Dept. of Gynaecology, Laarbeeklaan 101, B-1090 Brussels, Belgium.
0 1986 Elsevier Science Publishers
Fig. 1. Transverse and sagittal mass in the left her&abdomen.
the fetal abdomen
show a unilateral
propriate; the right kidney and the amount of amniotic fluid were normal. The sonolucent intrafetal mass, however, was larger, now having an estimated volume of about 100 ml (Fig. 1). Notwithstanding the normal amount of amniotic fluid, indicating a normal functioning kidney, and the lack of evidence that the cyst was compressing the surrounding fetal structures (e.g. no ascites, no other effusions, no cardiac compromise) it was decided to perform a percutaneous puncture of the cyst. Why? First of all, because the cyst was still growing - from 80 ml to 100 ml in 2 wk; secondly, we were not absolutely sure of the nature of the liquid collection. So fluid analysis could not only help us toward a diagnosis, but also provide a rapid result (2 wk) for chromosome analysis . At 30 wk of pregnancy the cyst was punctured with a spinal needle under ultrasonic control using a General Electrics RT 3000 real-time apparatus with a 3.5 MHz transducer. 100 ml of clear yellowish fluid were removed. Contrast material was not instilled for pyelography. Neither anesthesia nor tocolysis was used during the procedure. The cardiac rhythm was normal. A few contractions following the procedure were successfully treated by rest and indomethacine 100 mg (rectally) daily, for 2 days. Cells were isolated from the fetal fluid to perform chromosome analysis. A normal karyotype (46 XY) was found. The supernatants were investigated for total
Fig. 2. Left: after puncture longitudinal scan through system.
the mass did not recur but no normal renal tissue could be visualized. Right: the normal right kidney: echogenic renal capsule, pyramids and collecting
protein and albumin. The concentrations of total protein (1.1 g/l) and albumin (0.14 g/l) confirmed the tentative ultrasonic identification of fetal urine . During the following weeks the mass did not recur (Fig. 2) and the clinical and sonographic evolution was normal. The patient went into spontaneous labour at 39 wk gestation. The delivery was uneventful, and a male infant weighing 3200 g was born spontaneously. Postnatal ultrasound controls did not show hydronephrosis, but a small left kidney with poor corticomedullary differentiation, a slightly distended pelvis and a thin cortex. The ureter was not seen. The right kidney was slightly hypertrophic but normal; the bladder also appeared normal. Vesico-ureteric reflux was ruled out by a normal urethrocystography. The glomerular filtration rate of each kidney was determined isotopically with 99mTeDTPA (= Te-diethylenetriaminepentaectic acid). This confirmed a poor renal function on the left, compensated by the right kidney: left/right ratio of 0.18. So, this case represents, in all probability, a unilateral ureteropelvic junction obstruction (UPJ) with some secondary renal compromise from type 4 cystic dysplasia. The cyst did not fill up again because the kidney produced little urine. The postnatal finding of a small kidney is not incompatible with this diagnosis. The baby, presently 1 yr old, is doing well, and thriving. He has had no urinary tract infection and is not hypertensive. No surgery has been performed to date.
Fetal anomalies are increasingly being detected by prenatal ultrasound examination. Anomalies of the fetal urinary tract are particularly amenable to diagnosis, due to the fact that fluid-filled structures are easily detected. Also oligohydramnios suggesting severe fetal renal failure is a sign of alarm. A unilateral single renal cystic mass is usually due to a ureteropelvic junction obstruction . However, distinguishing between hydronephrosis with advanced destruction of the kidney and a multicystic kidney may be difficult. (A multicystic kidney is an extreme form of dysplasia, mostly associated with ureteric atresia.) Usually, intervention is not required in a case of a unilateral renal cystic mass, with a normally functioning contralateral kidney and a normal amount of amniotic fluid, because renal damage is already severe and irreversible by the time the pathology is detected by ultrasound [l-3]. However, improvement of renal function after postnatal decompression has been described. In this particular case, prenatal percutaneous puncture of this growing cyst was carried out in order to confirm the ultrasonic diagnosis and to provide a rapid karyogram. Moreover, further growth of the cyst might have caused feto-pelvic disproportion at the time of delivery. Prevention of progression of renal failure was only a secondary goal. After puncture, dilatation did not recur. This may be due to better outflow after decompression, but may also be an indication of poor renal function. Postnatal evaluation revealed a small, poorly functioning left kidney. The ureter was not seen on IVP, which may be due to a ureteric obstruction or to insufficient concentration of contrast medium caused by poor renal function. So, we cannot conclude that postnatal renal function has been favourably modified by this prenatal treatment. Yet we believe that ultrasonic guided fetal puncture is a safe procedure which can be helpful in establishing an ultrasound diagnosis. References 1 Campbell 494-500. 2 Diament 435-440. 3 Hobbins Williams 4 Lenz S, analysis
MJ, Fine RN. Fetal hydronephrosis.
JC, Winsberg F, Berkowitz RL. Ultrasonography & Wilkins; 1984: 148-156. Lund-Hansen T, Bang J. A possible prenatal on fetal urine. Prenatal Diagn 1985; 259-267.
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Clin Obstet Gynaecol1983; J Pediatr