Antenatal diagnosis of renal anomalies with ultrasound

Antenatal diagnosis of renal anomalies with ultrasound IV. Bilateral multicystic kidney disease Mary D' Alton, M.D., Roberto Romero, M.D., Peter Grannum, M.D., Louis DePalma, M.D., Philippe Jeanty, M.D., and John C. Hobbins, M.D. New Haven, Connecticut Bilateral multicystic kidney disease is a congenital disorder that is fatal in the newborn period. A series of nine cases of bilateral multicystic kidney disease diagnosed prenatally by ultrasound is presented. Ultrasound criteria necessary for the diagnosis are (1) bilateral multicystic kidneys, (2) loss of renal architecture, (3) nonvisualization of the fetal bladder, and (4) absence of amniotic fluid. Seven of the nine cases had autopsy confirmation of the diagnosis. Three cases had other associated congenital anomalies. Precise prenatal diagnosis may allow patients the option of elective abortion or may prevent unnecessary obstetric intervention. We propose that a reliable diagnosis can be made with prenatal ultrasound. (AM J OSSTET GVNECOL 1986;154:532-7.)

Key words: Bilateral multicystic kidney disease, ultrasound diagnosis, congenital anomalies

Bilateral multicystic kidney disease is a disorder that is fatal in the newborn period.' Multicystic kidney disease has been called polycystic kidney disease, multicystic dysplastic kidney disease, and dysplastic kidney disease. In this communication multicystic kidney disease refers to the type II form of Osathanondh and Potter's c1assification 2 of polycystic disease of the kidney. Type II multicystic kidney diseaase is usually bilateral.' Less often only one kidney or a segment of one kidney is affected. The kidneys may be normal or increased in size (type IIA) or reduced in size (lIB). On gross examination the affected kidneys may be likened to a "cluster of grapes" with complete loss of normal reniform shape. Histologically, thick-walled cysts lined by cuboidal or columnar epithelium, surrounded by immature mesenchymal stroma, are seen. Islands of cartilage, abnormal glomeruli, and fibroblastic proliferation may also be identified. Since bilateral multicystic kidney disease is fatal in the newborn period,' the importance of precise prenatal diagnosis of this condition is twofold. First, prenatal diagnosis is possible early enough in gestation to allow patients the option of elective abortion. Second, if the diagnosis is made in the late second trimester or the third trimester, it may prevent unnecessary obstetric intervention. In an effort to test the hypothesis that From the Departments of Obstetrics and Gynecology and Pathology, Yale University School of Medicine. Received for publication November 6, 1984; accepted November 7, 1985. Reprint requests: Mary D'Aiton, M.D., Department of Obstetrics and Gynecology, Ottawa Civic Hmpital, 1053 Carling Ave., Ottawa, Ontario, Canada K7Y 4£9

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a reliable prenatal diagnosis can be made with ultrasound, this report reviews our experience during a 4year period in the diagnosis of this rare but lethal disease.

Material and methods For the time period January 1, 1980, to April 1, 1984, the following records were reviewed: (1) ultrasound records in which the primary diagnosis was multicystic kidney disease; (2) ultrasound records in which other congenital anomalies were the primary diagnosis, to determine if multicystic kidney disease was also diagnosed; (3) autopsy records of perinatal deaths, to confirm the prenatal ultrasound diagnosis of multicystic kidney disease and to determine if prenatal sonograpy had missed or incorrectly diagnosed multicystic kidney disease. Sonographic examinations were performed with a static B scanner with a 3.5 MHz transducer (Picker, North Haven, Connecticut) and/or linear array realtime equipment with a 3.5 MHz transducer (General Electric, Milwaukee, Wisconsin; ADR, Tempe, Arizona; Picker; Toshiba SAL SOA, Tustin, California) or a mechanical sector scanner (ADR). Our prenatal diagnosis was based on the ultrasound findings of (1) bilateral multicystic abdominal masses, (2) loss of normal renal architecture, (3) failure to visualize the fetal bladder, and (4) absence of amniotic fluid (Fig. 1).

Results During this period nine cases of bilateral multicystic kidney disease and three cases of unilateral multicystic

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Fig. 1. Transverse scan through fetal abdomen. The multicystic kidneys (MK) are seen as bilateral masses filled with echofree areas on both sides of the spine (5). Note the absence of amniotic fluid.

kidney disease were diagnosed prenatally. Pathologic confirmation was not available in the unilateral cases since operation was not performed to remove the diseased kidney. With one exception (Case No. 10), we have restricted our communication to bilateral multicystic kidney disease. Table I lists the pertinent clinical features for each case of bilateral multicystic kidney disease. Seven of the nine cases were diagnosed before 24 weeks. All seven patients elected to terminate the pregnancy. In the two cases diagnosed after 24 weeks, vaginal delivery occurred at 38 and 41 weeks, respectively. Autopsy information was available in seven of the nine cases, and in all seven the prenatal diagnosis was confirmed. The gross and microscopic features from the autopsy of one of these infants are displayed in Figs. 2, 3, and 4, and these serve as classic examples of the pathologic characteristics of multicystic kidney disease. Associated congenital anomalies were noted ultrasonically in three patients. In Case No.3, the fetal stomach was not visualized and a diagnosis of tracheoesophageal fistula was entertained. In Case No.5 there was evidence of ascites, pericardial effusion, and right ventricular hypertrophy. In Case No.7 dilated lateral ventricles were observed. Autopsy confirmed the findings in Cases No.3 and No.5, but permission for autopsy was not given in Case No.7. A tenth case deserves special mention. In this patient ultrasound examination at 35 weeks of gestation demonstrated evidence of bilateral multicystic abdominal masses, loss of normal renal architecture, and non vi-

Fig. 2. Anterior view of horseshoe-shaped multicystic kidneys in a 22-week fetus. Note the "cluster of grape" morphologic features and the concomitant bilateral ureteral abnormality. The proximal segments of the ureters are stenotic while the distal portions are atretic. In addition, the bladder is hypoplastic.

sualization of the fetal bladder. There was only a moderate degree of oligohydramnios. It was felt that a definitive diagnosis of bilateral multicystic kidney disease could not be made in the presence of amniotic fluid. Two differential diagnoses were considered: bilateral high-level ureteropelvic junction obstruction or a combination of multicystic kidney disease on one side and a ureteropelvic junction obstruction on the other. After delivery renal function studies were normal. An intravenous pyelogram demonstrated a high ureteropelvic junction obstruction on the left side and a nonfunctioning right kidney. A left ureteropyeloplasty was performed. The right kidney was thought to be multicystic and was not removed at the time of operation. A followup intravenous pyelogram at 3 years demonstrated a normally functioning left kidney and no visualization of the right kidney.

Comment The prenatal diagnosis of many renal abnormalities is now possible. Obstructive uropathy,' renal agenesis,' and infantile polycystic kidney disease' have been the subject of previous reports from this unit. Currently in the literature are 10 case reports of unilateral multi-

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Table I. Clinical and sonographic data in affected fetuses with bilateral multicystic kidney disease

Age

Parity

Gestational age at diagnosis (wk)

18

Primiparous

18

Oligohydramnios, level I scan

2

32

G2SAB,

17

Oligohydramnios, level I scan

3

28

G2SAB,

20

Oligohydramnios, level I scan

4

21

G,

21

Cystic mass, level I scan

5

24

G2SAB,

23

Cystic mass, level I scan

6

28

G,P 2

22

7

21

G2 P,

18

Previous infant with rhabdomyosarcoma Class F diabetes

8

31

G,

26

Oligohydramnios, level I scan

9

22

G,

35

Oligohydramnios, level I scan

Case No.

Ultrasound findings Reason for scan

Appearance of kidneys

Bilateral enlargement; multiple small cysts; largest cyst 3 x 1.8 cm Large cyst, 3.7 x 3.3 cm (L); large kidney with multiple small cysts (R) Right kidney, 4.0 x 2.7 cm with multiple cysts; left kidney, I. 0 x I. 0 with cysts

I

Bladder

I

Amniotic fluid

Absent

Not detectable

Absent

Not detectable

Absent

Not detectable

Right kidney, normal size with cysts; large cystic structure (L), 7.5 x 8 cm Bilateal large kidneys replete with small cysts

Absent

Not detectable

Absent

Not detectable

Bilateral large kidneys of equal size, replete with cysts

Absent

Not detectable

Right kidney, enlarged with multiple cysts; left kidney, normal size with multiple cysts Bilateral enlargement of kidneys of equal size with multiple cysts

Absent

Not detectable

Absent

Not detectable

Absent

Not detectable

Bilateral enlargement of kidneys of equal size

G = Gravidity; SAB = spontaneous abortions; P = parity; L = left; R = right.

Fig. 3. Frozen section of PQtter's type II or multicystic kidney. Note the thick-walled cysts with a rather flattened epithelium. In addition, immature mesenchymal stroma and tubules are seen.

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Pregnancy outcome Outcome

Prostaglandin termination Prostaglandin termination Prostaglandin termination

Prostaglandin termination Prostaglandin termination Prostaglandin termination

Autopsy findings

Type II Potter's syndrome; combined kidney weight 18 gm Type II Potter's syndrome; combined kidney weight 22 gm; 46,XY karyotype Type II Potter's syndrome; tracheoesophageal fistula; congenital absence of radius and thumb bilaterally; 46,XY karyotype Type II Potter's syndrome Type II Potter's syndrome; hypoplastic left ventricle; hypertrophy of right ventricle; 46,XX karyotype Type II Potter's 46,XY karyotype

Prostaglandin termination

Refused autopsy

Vaginal delivery 41 wk; infant died within 1 hr of birth; Potter's phenotype Delivery at 38 wk; infant died within 1 hr of birth; Potter's phenotype

Refused autopsy

Type II Potter's syndrome; kidneys 29.5 gm; 46,XY karyotype

cystic kidney disease 6- '1 and one case report of bilateral multicystic kidney disease. 15 This report deals with nine cases of bilateral multicystic kidney disease. When the diagnosis of bilateral multicystic kidney disease is entertained, one must also consider infantile polycystic kidney disease and bilateral ureteropelvic junction obstruction. Both bilateral multicystic kidney disease and infantile polycystic kidney disease are associated with loss of normal renal architecture, absence of amniotic fluid, and absence of the fetal bladder on ultrasound examination. The kidneys in infantile polycystic kidney disease are large, homogeneous, hyperechogenic, solid masses (Fig. 5), whereas in multicystic kidney disease numerous echo-free areas are seen throughout the kidneys (Fig. 1). In infantile polycystic kidney disease the kidney circumference to abdominal circumference ratio is usually greater than 2 SD above the mean. In contrast, multicystic kidneys may be mildly or greatly enlarged (IIA) or even reduced in size (lIB) (Figs. 1 and 6). It should be noted, however, that in

Fig. 4. The presence of cartilage and interstitial lymphocytic infiltrates are additional features that may be seen in multicystic kidneys.

the early stages of infantile polycystic kidney disease the kidney size may be normal and amniotic fluid may be present.' Hydronephrosis due to ureteropelvic junction obstruction can usually be clearly differentiated from multicystic kidney disease. '7 Particular attention must be paid to the renal architecture and identification of the renal pelvis. We found the following criteria useful for differentiation: (1) Several cystic masses separated by interfaces are seen in multicystic kidney disease whereas the dilated calyces in hydronephrosis are seen as hypoechogenic nonspherical areas radiating from the renal pelvis; (2) the largest cyst in multicystic kidney disease has a noncentrallocation; (3) in multicystic kidney disease one often fails to identify a definite renal parenchymal rim. Severe forms of hydronephrosis, however, may produce large cystic structures where no normal renal architecture is identified (Case No. 10) and may be extremely difficult to differentiate from multicystic kidney disease. As with any form of prenatal diagnosis, the importance of accuracy in diagnosis cannot be overstated. Seven of the nine cases had autopsy-confirmed bilateral multicystic kidney disease. The remaining two cases in

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Fig. 5. Transverse scan demonstrating spine (S) and large polycystic kidneys (K). Note the loss of normal kidney architecture and the hyperechogenicity of the kidneys. which autopsy was refused had the classic Potter phenotype, strongly suggesting that the diagnosis was correct. Additional reviews of the autopsy records in perinatal deaths did not identify any patient that had a missed diagnosis or incorrect diagnosis of multicystic kidney disease in the ultrasound unit. Because of the common association with other congenital anomalies, a more comprehensive scan is indicated. Detection may sometimes be difficult because of the absence of amniotic fluid. For example, in Case No.3 the bilateral absence of the radius and thumb was not diagnosed prenatally. The underlying pathogenesis of multicystic kidney disease appears to be a severe insult to the developing kidney before 8 to 10 weeks of gestation. The classic teaching is that this is a sporadic event with a very low recurrence risk. 2 However, Roodhooft et al. 18 have recommended that parents of children with bilateral renal agenesis and multicystic kidney disease be counseled about two risks, an increased risk (4.4% in their study) of another severely affected child in a subsequent pregnancy and a risk to themselves and siblings of having silent genitourinary malformations. It seems prudent to counsel patients about the uncertain risk of recurrence and the availability of prenatal diagnosis with ultrasound in the early second trimester for a future pregnancy. The most striking feature that we noted from our experience was the total absence of demonstrable amniotic fluid in all nine cases of bilateral multicystic kid-

Fig. 6. This is another example of multicystic kidneys. There is a difference in size between the two kidneys and, when compared with those in Fig. 1, it is clear they are much larger m sIze.

ney disease. The tenth case described in this communication is one where the differential diagnosis from ureteropelvic junction obstruction was difficult. In retrospect, the most helpful ultrasonic finding was the presence of amniotic fluid. The presence of amniotic fluid indicates some kidney function and makes the diagnosis of bilateral multicystic kidney disease unlikely. In conclusion, an accurate prenatal diagnosis of multicystic kidney disease can be made with ultrasound. We wish to thank Ingeborg H. Venus, M.S., for assisting in the collation of the above data. REFERENCES 1. Potter EL, Craig JM. Pathology of the fetus and the newborn. 3d ed. Chicago: Year Book, 1975:447.

2. Osathanondh V, Potter EL. Pathogenesis of polycystic kidneys: historical survey. Arch Pathol 1964;77:459. 3. Hobbins ]C, Romero R, Grannum P, Berkowitz RL, Cullen M, Mahoney M. Antenatal diagnosis of renal anomalies with ultrasound. 1. Obstructive uropathy. AM] OB· STET GVNECOL 1984; 148:868. 4. Romero R, Cullen M, Grannum P, et al. Antenatal diagnosis of renal anomalies with ultrasound. Ill. Bilateral renal agenesis. AM] OBSTET GVNECOL 1985;151:38. 5. Romero R, Cullen M, ]eanty P, et al. The diagnosis of

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6. 7. 8. 9. 10.

II.

congenital renal anomalies with ultrasound. II. Infantile polycystic kidney disease. AM ] OBSTET GYNECOL 1984; 150:259. Mendoza SA, Griswold WR, Leopold GR, Kaplan GW. Intrauterine diagnosis of renal anomalies by ultrasonography. Am] Dis Child 1979; 133: 1042. Older RA, Hinman CG, Crane LM, Cleeve DM, Morgan CL. In utero diagnosis of multicystic kidney by gray scale ultrasonography. Am] Radiol 1979; 133: 130. Legarth], Verder H, Gronvall S. Prenatal diagnosis of multicystic kidney by ultrasound. Acta Obstet Gynecol Scand 1981 ;60:523. Friedberg ]E, Mitnick ]S, Davis DA. Antepartum ultrasound detection of multicystic kidney. Radiology 1979; 131:198. dell' Agnola CA, Ferrazzi E, Gargiulo M, Cabibbe G, Brambati B, Nicolini U. Difficulties in "real time" ultrasound diagnosis of fetal urological anomalies. Z. Kinderchir 1982;37:34. Henderson SC, Van Kolken R], Rahatzad M. Multicystic kidney with hydramnios. ]CU 1980;8:249.

12. Santos-Ramos R, Duenhoelter ]H. Diagnosis of congenital fetal anomalies by sonography. Obstet Gynecol 1975; 45:279. 13. Lee TG, Blake S. Prenatal fetal abdominal ultrasonography and diagnosis. Radiology 1977;124:475. 14. Bateman BG, Brenbridge ANAG, Buschi AJ. In utero diagnosis of multicystic kidney disease by sonography. ] Reprod Med 1980;25:256. 15. Bartley]A, Golbus MS, Filly RA, Hall BD. Prenatal diagnosis of dysplastic kidney disease. Clin Genet 1977; 11:375. 16. Grannum P, Bracken M, Silverman R, Hobbins ]C. Assessment of fetal kidney size in normal gestation by comparison of ratio of kidney circumference to abdominal circumference. AM] OBSTET GYNECOL 1980; 136:249. 17. Stuck K], Koff SA, Silver TM. Ultrasonic features ofmulticystic dysplastic kidney: expanded diagnostic criteria. Radiology 1982;143:217. 18. Roodhooft AM, Birnholz]C, Holmes LB. Familial nature of congenital absence and severe dysgenesis of both kidneys. N Engl] Med 1984;310:1341.

Ultrasound differentiation of the competent from the incompetent cervix: Prevention of preterm delivery William H. Michaels, M.D., Cynthia Montgomery, M.D., James Karo, M.D., John Temple, M.D., Joel Ager, Ph.D., and Jane Olson, B.A. Southfield, Michigan To evaluate the feasibility of the use of serial ultrasound measurements of cervical length, membrane protrusion, and dilatation to discriminate between the competent and the incompetent cervix, 107 at-risk patients and 30 control subjects were examined prospectively. Patients were divided into five groups based on treatment and method of diagnosis. Epidemiologic, ultrasound, and outcome data were analyzed. Means and standard deviations for ultrasound measurements were established. Highly significant differences between all prediagnostic and postdiagnostic-pretreatment measurements were found (p < 0.001). Highly significant differences were also found between all postdiagnostic-pretreatment and postdiagnostic-posttreatment measurements (p < 0.001). No significant differences between prediagnostic and postdiagnostic-posttreatment measurements were noted. The incidence of preterm delivery was significantly higher among untreated diagnosed patients (p < 0.01). By combined clinical and ultrasound criteria 51 patients (47.7%) were identified as not having cervical incompetency. Fifty-six patients (52.3%) were diagnosed. (AM J OSSTET GYNECOL 1986;154:537-46.)

Key words: Incompetent cervix, sonographic measurement, preterm birth

The diagnosis of cervical incompetency is routinely accomplished by reviewing the clinical history of multigravid patients at risk. l If a classic history andlor previous cerclage is not noted, the clinician must rely on

From the Departments of Obstetrics and Gynecology and Diagnostic Imaging and Interventional Radiology, Providence Hospital. Received for publication July 22, 1985; accepted November 25, 1985. Reprint requests: William H. Michaels, M.D., Providence Medical Building, 22250 Providence Drive, #L-100, Southfield, MI 48075.

waiting for either the appearance of premonitory symptoms or changes on pelvic examination. At best these methods of diagnosis are often unreliable and subjective, and they are frequently observed late in the developmental time course of this condition. The need to rely on past history to determine whether patients are at risk places the primigravid patient with congenital incompetency in a more vulnerable position. Quite often the diagnosis is missed entirely. Anatomically, about half of the cervix is not accessible by routine vaginal examination. It is therefore not unreasonable to expect that anatomically short cervices

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