- Email: [email protected]
Contralateral renal abnormalities in multicystic-dysplastic kidney disease
Contralateral renal abnormalities in multicystic-dysplastic kidney disease Bassam Atiyeh, MD, Douglas Husmann, MD, a n d Michel Baum, MD From the Departments of Pediatrics, Internal Medicine, and Urology, University of Texas Southwestern Medical Center at Dallas Multicystic-dysplastic kidney (MCDK) disease has b e e n a s s o c i a t e d with contralateral genitourinary tract abnormalities; however, neither the nature nor the p r e v a l e n c e of the contralateral renal lesion has been d e l i n e a t e d . We retrospectively studied patients with MCDK disease to d e t e r m i n e the p r e v a l e n c e of contralateral renal abnormalities and of other urologic anomalies. Forty-nine patients, ranging in a g e from n e o n a t e s to 6 years, were e x a m i n e d by renal ultrasonography, excretory urography or nuclear m e d i c i n e scanning, and voiding cystourethrography; 51% of the patients had an associated urologic abnormality. The abnormality was contralateral to the MCDK in 19 patients (39%), ipsilateral in 3 patients (6%), and involved the b l a d d e r wall in 3 patients (6%). The most c o m m o n contralateral genitourinary tract abnormality was vesic o u r e t e r a l reflux (18%) f o l l o w e d by ureteropelvic junction obstruction (12%). We c o n c l u d e that urologic anomalies are c o m m o n in patients with MCDK disease; contralateral vesicoureteral reflux is the most c o m m o n abnormality identified. (J PEDIATR1992;121:65-7) Renal dysplasia is usually, but not invariably, a unilateral disease associated with ipsilateral atresia or hypoplasia of the ureter and the renal pelvis. 1 Renal dysplasia is a congenital lesion believed to have been acquired in utero as a result of failed coordination of development of the metanephros and the branching ureteric bud. 2 Dysplastic kidneys may be small and solid, or large with a variable number of cysts, the latter condition being referred to as multicystic-dysplastic kidney disease. Gordon et al. 3 estimated that the incidence of unilateral M C D K disease was 1 in 4300 live births. Previous studies have reported contralateral abnormalities in 20% to 80% of patients with M C D K disease. 1, 4-12 However, several of these studies included autopsy findings from fetuses and neonates who often had multiple congenital abnormalities. In addition, voiding cystourethrography was rarely performed. Thus the prevalence of contralateral renal abnormalities in patients with an M C D K is unknown. Submitted for publication Nov. 15, 1991; accepted Jan. 10, 1992. Reprint requests: Michel Baum, MD, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75235-9063. 9/20/36203
Table I. Age distribution of patients with M C D K disease at time of diagnosis
Patients (n
=
56)
Age
No.
%
Prenatal Before 1 mo Between 1 mo and 1 yr After 1 yr
22 20 9 5
39 36 16 9
The purpose of our study was to determine the prevalence of contralateral renal abnormalities and other associated urologic anomalies in patients with M C D K disease. I
MCDK
Multicystic-dysplastic kidney
[
METHODS The charts and radiologic records of all patients with the diagnosis of M C D K disease who were referred or admitted to the Children's Medical Center of Dallas between January 1980 and December 1990 were reviewed. In all patients the diagnosis of M C D K disease was determined with the use of abdominal ultrasonography; M C D K disease was
65
66
Atiyeh, Husmann, and Baum
The Journal of Pediatrics July 1992
T a b l e II. Prevalence of contralateral renal abnormalities in patients with MCDK disease No. of patients Reflux
UPJ obstruction
Right MCDK 5 2 (n = 22) Left MCDK 4 4 (n = 27) TOTAL 9 (18) 6 (12) uPJ, Ureteropelvicjunction; uvJ, ureterovesicaljunction. *Values in parenthesesare percentages.
characterized by multiple noncommunicating cysts that were randomly arranged. The cysts ranged in size from less than 1 mm to several centimeters in diameter. Of the 56 patients studied, 31 were girls. The patients ranged in age from newborn infants to 6 years of age. Excretory urography, nuclear medicine scanning (with technetium Tc 99m diethylenetriaminepentaacetic acid), or both were performed in all the patients. In addition, voiding cystourethrography was performed in 49 patients to determine whether vesicoureteral reflux was present. The International Grading System was used to grade the severity of reflux. 13 Seven patients did not have all the examinations performed and were not included in the analysis of the prevalence of urologic abnormalities in patients with MCDK disease. RESULTS Twenty-eight patients had MCDK disease on the right side and 28 on the left. In 42 (75%) of the 56 patients the MCDK was discovered during the perinatal period, and in 51 (91%) patients the diagnosis was made daring the first year of life (Table I). Of the 42 patients in whom the diagnosis was made in the perinatal period, 22 (52%) had renal abnormalities noted on prenatal ultrasonography, and 13 (31%) had a palpable abdominal mass at birth. In the remaining seven neonates, the diagnosis was made during evaluation for gastrointestinal anomalies (three neonates), urinary tract infection (two), congenital heart disease (one), and respiratory distress (one). In nine patients the diagnosis of MCDK disease was made after the neonatal period but before the first birthday. These patients had an examination of the genitourinary tract for a urinary tract infection (five patients), failure to thrive (two) vomiting and diarrhea (one), or precocious thelarche (one). in only five patients (9%) the diagnosis of MCDK disease was made after the first year of life. These patients were examined for recurrent epididymitis (two patients), an undescended testicle (one), abdominal pain (one), and urinary tract infection and enuresis (one).
UVJ obstruction
Dysplasia (or llypoplasia)
Total
2
1
10 (45)*
0
1
9 (33)
2 (4)
2 (4)
19 (39)
Of the 56 patients, 49 had an examination consisting of renal ultrason0graphy, voiding cystourethrography, and either excretory urography or nuclear medicine scanning; these 49 patients were included in analyzing the prevalence of urologic abnormalities. Nineteen patients (39%) had a contralateral renal abnormality (Table II). Vesicoureteral reflux, the most common contralateral abnormality identified, was found in nine patients (18%). The reflux was grade II in six patients, grade III in two patients, and grade IV in one patient. There was one patient with bilateral grade III reflux. Obstruction of the ureteropelvic junction was the second most common lesion9 Among the two patients with obstruction of the ureterovesical junction, one had extrinsic compression of the left ureter at the pelvic brim from a dilated right distal ureter. In addition, six patients with MCDK disease had other urologic abnormalities, including three with a bladder wall diverticulum and three with an ipsilateral ureter draining into an ipsilateral seminal vesicle, with associated ipsilateral vesicoureteral reflux. Thus the prevalence of associated urologic abnormalities in patients with MCDK disease was 51%. DISCUSSION Unilateral MCDK disease usually causes no symptoms. p The condition"is often discovered during routine prenatal evaluation or during physical examination of neonates. In our study, all the patients had unilateral MCDK disease, with the contralatcral side noncystic. Kleiner et al. 11 described 27 patients with MCDK disease detected by prcnatal sonograms; contralateral renal abnormalities wcrc found in 10 of the fetuses (37%), including bilateral MCDK diseas~e in 5 (19%) and contralateral renal hypoplasia or agcncsis in 4 (15%). Similarly, the prevalence of bilateral MCDK disease reported in other series was as high as 20%.4, s, 11 These same studies also noted a higher prevalence of contralatcral renal hypoplasia and dysplasia. The reason for this higher prevalence of severe contralateral renal dysplasia and hypoplasia, and of bilateral MCDK discase, may be that their study populations consisted mainly
Volume 121 Number 1
of neonates and fetuses in whom autopsies had been performed, whereas our study population included only neonatal survivors and older children referred to us for evaluation of an abdominal mass. Previous studies have reported contralateral renal abnormalities in 20% to 80% of patients with MCDK disease 1,412; however, the nature of the contralateral lesion was often not fully evaluated. The most common contralateral lesion was another MCDK or hydronephrosis caused by obstruction of the ureteropelvic junction. Vesicoureteral reflux, on the other hand, was rarely reported. In 38 patients who ranged in age from birth to 16 years, Greene et al. 4 identified contralateral genitourinary tract abnormalities in 20 patients (53%); 8 patients (21%) had bilateral MCDK disease, and 3 patients (8%) had hydronephrosis caused by obstruction of the ureteropelvic junction. Radiologic evaluation, however, included excretory urography but no voiding studies. Pathak and Williams6 studied 21 patients with MCDK disease who were younger than 2 years of age at the time of diagnosis; contralateral hydronephrosis was identified in 11 patients (52%) and bilateral MCDK disease in 1 patient (5%). Again, no voiding studies were performed. De Klerk et al. 12 studied 29 infants with MCDK disease; bilateral reflux was identified in 2 Patients (7%) and bilateral MCDK disease in 3 (10%); however, voiding cystourethrography was performed in only 7 patients. The reason for the discrepancy in the prevalence of contralateral vesicoureteral reflux between our study and earlier studies is likely that voiding cystourethrography was rarely performed during the earlier studies; thus several patients with vesicoureteral reflux could have been missed. In addition, the higher incidence of contralateral hydronephrosis in these earlier studies could have been due to vesicoureteral reflux. The high prevalence of bilateral MCDK disease in the studies noted above, however, cannot be explained. Urinary tract infections have been associated with MCDK disease. We had eight patients with a history of urinary tract infection. The infection was associated with contralateral vesicoureteral reflux in three patients, contralateral ureterovesical junction obstruction in one, a bladder wall diverticulum in one, and extrinsic compression of the contralateral ureter in one patient. In two patients there was no evidence of genitourinary tract abnormalities, but voiding cystourethrography was not performed in one of these pa-
Contralateral renal abnormalities in M C D K disease
67
tients. Thus most of the patients who had a urinary tract infection had a genitourinary tract abnormality that could have predisposed them to a urinary tract infection. We conclude that MCDK is a common cause of a neonatal abdominal mass. A multicystic-dysplastic kidney is usually unilateral, but other urologic abnormalities are frequently present. The majority of these abnormalities are contralateral to the MCDK, and vesicoureteral reflux is the most common contralateral genitourinary tract abnormality identified. We recommend that ultrasonography, excretory urography or nuclear medicine renal scan, and voiding cystourethrography be performed to identify contralateral renal and other urologic abnormalities. REFERENCES
1. Glassberg K, Filmer R. Renal dysplasia, renal hypoplasia,and cystic disease of the kidney. In: Kelalis P, King L, Belman A, eds. Clinical pediatric urology. Philadelphia: WB Saunders, 1985:922-71. 2. Bernstein J. The morphogenesisof renal parenchymal maldevelopment (renal dysplasia). Pediatr Clin North Am 1971; 18:395-407. 3. Gordon A, Thomas D, Arthur R, Irving H. Multicystic dysplastic kidney: is nephrectomy still appropriate. J Urol 1988;140:1231-4. 4. Greene L, Feinzaig W, Dahlin D. Multieystic dysplasia of the kidney: with special reference to the contralateral kidney. J Urol 1971;105:482-7. 5. Walker D, Fenell R, Garin E, Richard G. Spectrum of multicystic renal dysplasia. Urology 1978;11:433-6. 6. Pathak I, Williams D. Multicystic and cystic dysplastic kidneys. Br J Urol 1964;36:318-31. 7. GipsonT, Anderson E, Bradford W. Multicystic renal dysplasia: pathologic and clinical observations in 22 cases. Clin Pediatr 1976;15:896-901. 8. Dungan J, Fernandez M, Abbitt P, et al. Multicystic dysplastic kidney:natural history of prenatally detected cases. Prenat Diagn 1990;10:175-82. 9. Kyau M. Roentgenologic triad of congenital multicystic kidney. Am J Roentgenol 1973;119:710-9. 10. Uehling D, Barber K. Unilateral multicystic kidney. J Urol 1966;96:286-9. 11. Kleiner B, Filly R, Mack L, Callen P. Multicystic dysplastic kidney: observations of contralateral disease in the fetal population. Radiology 1986;161:27-9. 12. De Kterk D, Marshall F, Jeffs R. Multicystic dysplastic kidney. J Urol 1977;118:306-8. 13. Lebowitz RL, Olbing H, Parkkulainen KV, Smellie JM, Tamminen-M6bius TE. International system of radiographic grading of vesicouretericreflux.Pediatr Radiol 1985;15:105-9.
Table I. Age distribution of patients with M C D K disease at time of diagnosis
Patients (n
=
56)
Age
No.
%
Prenatal Before 1 mo Between 1 mo and 1 yr After 1 yr
22 20 9 5
39 36 16 9
The purpose of our study was to determine the prevalence of contralateral renal abnormalities and other associated urologic anomalies in patients with M C D K disease. I
MCDK
Multicystic-dysplastic kidney
[
METHODS The charts and radiologic records of all patients with the diagnosis of M C D K disease who were referred or admitted to the Children's Medical Center of Dallas between January 1980 and December 1990 were reviewed. In all patients the diagnosis of M C D K disease was determined with the use of abdominal ultrasonography; M C D K disease was
65
66
Atiyeh, Husmann, and Baum
The Journal of Pediatrics July 1992
T a b l e II. Prevalence of contralateral renal abnormalities in patients with MCDK disease No. of patients Reflux
UPJ obstruction
Right MCDK 5 2 (n = 22) Left MCDK 4 4 (n = 27) TOTAL 9 (18) 6 (12) uPJ, Ureteropelvicjunction; uvJ, ureterovesicaljunction. *Values in parenthesesare percentages.
characterized by multiple noncommunicating cysts that were randomly arranged. The cysts ranged in size from less than 1 mm to several centimeters in diameter. Of the 56 patients studied, 31 were girls. The patients ranged in age from newborn infants to 6 years of age. Excretory urography, nuclear medicine scanning (with technetium Tc 99m diethylenetriaminepentaacetic acid), or both were performed in all the patients. In addition, voiding cystourethrography was performed in 49 patients to determine whether vesicoureteral reflux was present. The International Grading System was used to grade the severity of reflux. 13 Seven patients did not have all the examinations performed and were not included in the analysis of the prevalence of urologic abnormalities in patients with MCDK disease. RESULTS Twenty-eight patients had MCDK disease on the right side and 28 on the left. In 42 (75%) of the 56 patients the MCDK was discovered during the perinatal period, and in 51 (91%) patients the diagnosis was made daring the first year of life (Table I). Of the 42 patients in whom the diagnosis was made in the perinatal period, 22 (52%) had renal abnormalities noted on prenatal ultrasonography, and 13 (31%) had a palpable abdominal mass at birth. In the remaining seven neonates, the diagnosis was made during evaluation for gastrointestinal anomalies (three neonates), urinary tract infection (two), congenital heart disease (one), and respiratory distress (one). In nine patients the diagnosis of MCDK disease was made after the neonatal period but before the first birthday. These patients had an examination of the genitourinary tract for a urinary tract infection (five patients), failure to thrive (two) vomiting and diarrhea (one), or precocious thelarche (one). in only five patients (9%) the diagnosis of MCDK disease was made after the first year of life. These patients were examined for recurrent epididymitis (two patients), an undescended testicle (one), abdominal pain (one), and urinary tract infection and enuresis (one).
UVJ obstruction
Dysplasia (or llypoplasia)
Total
2
1
10 (45)*
0
1
9 (33)
2 (4)
2 (4)
19 (39)
Of the 56 patients, 49 had an examination consisting of renal ultrason0graphy, voiding cystourethrography, and either excretory urography or nuclear medicine scanning; these 49 patients were included in analyzing the prevalence of urologic abnormalities. Nineteen patients (39%) had a contralateral renal abnormality (Table II). Vesicoureteral reflux, the most common contralateral abnormality identified, was found in nine patients (18%). The reflux was grade II in six patients, grade III in two patients, and grade IV in one patient. There was one patient with bilateral grade III reflux. Obstruction of the ureteropelvic junction was the second most common lesion9 Among the two patients with obstruction of the ureterovesical junction, one had extrinsic compression of the left ureter at the pelvic brim from a dilated right distal ureter. In addition, six patients with MCDK disease had other urologic abnormalities, including three with a bladder wall diverticulum and three with an ipsilateral ureter draining into an ipsilateral seminal vesicle, with associated ipsilateral vesicoureteral reflux. Thus the prevalence of associated urologic abnormalities in patients with MCDK disease was 51%. DISCUSSION Unilateral MCDK disease usually causes no symptoms. p The condition"is often discovered during routine prenatal evaluation or during physical examination of neonates. In our study, all the patients had unilateral MCDK disease, with the contralatcral side noncystic. Kleiner et al. 11 described 27 patients with MCDK disease detected by prcnatal sonograms; contralateral renal abnormalities wcrc found in 10 of the fetuses (37%), including bilateral MCDK diseas~e in 5 (19%) and contralateral renal hypoplasia or agcncsis in 4 (15%). Similarly, the prevalence of bilateral MCDK disease reported in other series was as high as 20%.4, s, 11 These same studies also noted a higher prevalence of contralatcral renal hypoplasia and dysplasia. The reason for this higher prevalence of severe contralateral renal dysplasia and hypoplasia, and of bilateral MCDK discase, may be that their study populations consisted mainly
Volume 121 Number 1
of neonates and fetuses in whom autopsies had been performed, whereas our study population included only neonatal survivors and older children referred to us for evaluation of an abdominal mass. Previous studies have reported contralateral renal abnormalities in 20% to 80% of patients with MCDK disease 1,412; however, the nature of the contralateral lesion was often not fully evaluated. The most common contralateral lesion was another MCDK or hydronephrosis caused by obstruction of the ureteropelvic junction. Vesicoureteral reflux, on the other hand, was rarely reported. In 38 patients who ranged in age from birth to 16 years, Greene et al. 4 identified contralateral genitourinary tract abnormalities in 20 patients (53%); 8 patients (21%) had bilateral MCDK disease, and 3 patients (8%) had hydronephrosis caused by obstruction of the ureteropelvic junction. Radiologic evaluation, however, included excretory urography but no voiding studies. Pathak and Williams6 studied 21 patients with MCDK disease who were younger than 2 years of age at the time of diagnosis; contralateral hydronephrosis was identified in 11 patients (52%) and bilateral MCDK disease in 1 patient (5%). Again, no voiding studies were performed. De Klerk et al. 12 studied 29 infants with MCDK disease; bilateral reflux was identified in 2 Patients (7%) and bilateral MCDK disease in 3 (10%); however, voiding cystourethrography was performed in only 7 patients. The reason for the discrepancy in the prevalence of contralateral vesicoureteral reflux between our study and earlier studies is likely that voiding cystourethrography was rarely performed during the earlier studies; thus several patients with vesicoureteral reflux could have been missed. In addition, the higher incidence of contralateral hydronephrosis in these earlier studies could have been due to vesicoureteral reflux. The high prevalence of bilateral MCDK disease in the studies noted above, however, cannot be explained. Urinary tract infections have been associated with MCDK disease. We had eight patients with a history of urinary tract infection. The infection was associated with contralateral vesicoureteral reflux in three patients, contralateral ureterovesical junction obstruction in one, a bladder wall diverticulum in one, and extrinsic compression of the contralateral ureter in one patient. In two patients there was no evidence of genitourinary tract abnormalities, but voiding cystourethrography was not performed in one of these pa-
Contralateral renal abnormalities in M C D K disease
67
tients. Thus most of the patients who had a urinary tract infection had a genitourinary tract abnormality that could have predisposed them to a urinary tract infection. We conclude that MCDK is a common cause of a neonatal abdominal mass. A multicystic-dysplastic kidney is usually unilateral, but other urologic abnormalities are frequently present. The majority of these abnormalities are contralateral to the MCDK, and vesicoureteral reflux is the most common contralateral genitourinary tract abnormality identified. We recommend that ultrasonography, excretory urography or nuclear medicine renal scan, and voiding cystourethrography be performed to identify contralateral renal and other urologic abnormalities. REFERENCES
1. Glassberg K, Filmer R. Renal dysplasia, renal hypoplasia,and cystic disease of the kidney. In: Kelalis P, King L, Belman A, eds. Clinical pediatric urology. Philadelphia: WB Saunders, 1985:922-71. 2. Bernstein J. The morphogenesisof renal parenchymal maldevelopment (renal dysplasia). Pediatr Clin North Am 1971; 18:395-407. 3. Gordon A, Thomas D, Arthur R, Irving H. Multicystic dysplastic kidney: is nephrectomy still appropriate. J Urol 1988;140:1231-4. 4. Greene L, Feinzaig W, Dahlin D. Multieystic dysplasia of the kidney: with special reference to the contralateral kidney. J Urol 1971;105:482-7. 5. Walker D, Fenell R, Garin E, Richard G. Spectrum of multicystic renal dysplasia. Urology 1978;11:433-6. 6. Pathak I, Williams D. Multicystic and cystic dysplastic kidneys. Br J Urol 1964;36:318-31. 7. GipsonT, Anderson E, Bradford W. Multicystic renal dysplasia: pathologic and clinical observations in 22 cases. Clin Pediatr 1976;15:896-901. 8. Dungan J, Fernandez M, Abbitt P, et al. Multicystic dysplastic kidney:natural history of prenatally detected cases. Prenat Diagn 1990;10:175-82. 9. Kyau M. Roentgenologic triad of congenital multicystic kidney. Am J Roentgenol 1973;119:710-9. 10. Uehling D, Barber K. Unilateral multicystic kidney. J Urol 1966;96:286-9. 11. Kleiner B, Filly R, Mack L, Callen P. Multicystic dysplastic kidney: observations of contralateral disease in the fetal population. Radiology 1986;161:27-9. 12. De Kterk D, Marshall F, Jeffs R. Multicystic dysplastic kidney. J Urol 1977;118:306-8. 13. Lebowitz RL, Olbing H, Parkkulainen KV, Smellie JM, Tamminen-M6bius TE. International system of radiographic grading of vesicouretericreflux.Pediatr Radiol 1985;15:105-9.