J Clin Ultrasound 20:197-199, MarcWApril 1992 0 1992 by John Wiley & Sons, Inc. CCC 0091-2751/92/030197-03$04.00
Complete Prenatal Urinary Tract Obstruction Caused by Congenital Megalourethra B. Simma, MD,* I. GaBner, MD,* C. Brezinka, MD,? H. Ellemunter, MD,* and A. Kreczy, MD,S
Megalourethra is a very rare congenital malformation characterized by a dilatation of the penile urethra due to a partial or complete absence of the corpus spongiosum and the corpora cavern o ~ a . ~This ’ ~ ’disorder ~ is often associated with imperforate anus, heart defects, other anomalies of the genitourinary tract (stenotic or atretic posterior urethra, megaureter, vesical diverticula, obstruction of the ureteropelvic junction, renal agenesis or hypoplasia), and other mesenchymal rnalformation~.~*~,~ CASE REPORT
Our patient was the first child of nonconsanguinous parents. A t 16 weeks, menstrual age (MA), the patient was referred to our department because of lack of amniotic fluid. Ultrasound examination revealed large intra-abdominal fluidfilled “cysts” with peristaltic movement and anhydramnion as well as hydronephrosis and hydroureter on the left and cysts in the right kidney. Karyotyping of cells from fluid obtained by aspiration of the intra-abdominal cyst showed a normal male karyogram. A t 21/22 weeks, MA, an extra-abdominal cystlike structure between the legs and many intraluminal echogenic foci in the intra-abdominal cysts were detected for the first time (Figure 1A and B). After the extra-abdominal cyst-like structure had been punctured, further ultrasound investigations showed no cyst between the legs, but surprisingly increasing amounts of amniotic fluid. The cysts in the right kidney became larger and the kidney could not be visualized after 33 ~
~
~
From the *Departments of Paediatrics, tGynaecology and Obstetrics, and $Pathology, University Clinics of Innsbruck, Austria. For reprints contact Burkhard Simma, MD, UniversiGtsklinik fur Kinderheilkunde, Anichstrasse 35, A-6020 Innsbruck. Austria.
weeks, MA. All the other ultrasound findings remained unchanged. At 39 weeks, MA, the infant was delivered by caesarean section. Birth weight was 2260g and the Apgar scores 51718. The newborn presented with multiple malformations, including esophageal atresia, imperforate anus, and a large floppy penis with a wide cleft in the ventral surface (Figure 1C). Abdominal X-ray showed enormously enlarged intestinal loops filled with gas and fluid, multiple radiopaque shadows in the upper abdomen, and a malformed sacrum (Fig. 2). Ultrasound examination revealed echogenic foci in the dilated bowels, hydronephrosis and hydroureter of the left kidney, and absent right kidney. Contrast examination of the urinary tract made through a therapeutic left nephrostomy disclosed concomitant stenosis of the posterior urethra. In spite of mechanical ventilation, the infant developed respiratory distress due to pulmonary hypoplasia and died at the age of 27 hours. In addition to the abnormalities already known, postmortem examination also disclosed rectovesical fistula, ventricular septa1 defect, splenic duplication, and atrophic right kidney. No erectile tissue was detected by penile histology. Both the corpus spongiosum and the corpora cavernosa were completely absent as is characteristic of the fusiform type of megalourethra.
DISCUSSION
Congenital megalourethra is a rare disorder of the penile ~ r e t h r a . ~Two . ~ distinct types are k n o ~ n ~ ’The ~ , ~less ’ ~severe : scaphoid megalourethra results from a deficient corpus spongiosum, whereas the fusiform type is due to the complete absence of both the corpus spongiosum and the corpora cavernosa. The urethra consequently lacks adequate support on its dorsal and ventral 197
SIMMA ET AL.
198
FIGURE 1. (A) 21/22 weeks, MA: cyst (t
+) between the legs. (FEM = femur) (B)21/22 weeks M A : intraabdominal cyst ( + + ) with enteroliths (C) large floppy penis with a wide cleft on the ventral aspect (from dorsal).
aspects and balloons during micturition,2,6thus causing an obstruction of urinary flow. Since the first description of a megalourethra by Nesbitt in 1955,6 11 cases of fusiform type megalourethra have been reported; all of them were associated with other severe mesenchymal a n ~ m a l i e s , ~ >such * ’ ~ ,as ~ upper urinary and gastrointestinal tract abnormalities (renal agenesis or hypoplasia, obstruction of the ureteropelvic junction, megaureter, stenotic or atretic posterior urethra, gastrointestinal stenosis, or atresia), deficiencies of abdominal muscles, and imperforate anus with rectourethral fistula. Fusiform megalourethra has a poorer prognosis226 than the scaphoid type; 9 of 11 patients died as newborns from serious associated malformations. No histopathological documentation of the penis was available for the 2 survivors.435 Enteroliths are intraluminal calcified meconium and may be caused by the mixing of meconium and urine due to a rectourinary fi~tu1a.l.~ Intraluminal calcifications associated with multiple gastrointestinal atresias are more frequently observed; their cause is still uncleare8 Enteroliths are demonstrable by plain X-radiography and ultrasound. In our patient the anhydramnion in combination with hydronephrosis suggested a complete obstruction of the urinary tract. At 22 weeks,
MA, ultrasound revealed a cyst-like structure between the legs (=megalourethra). “Cyst” puncture was followed by an increase in amniotic fluid. Finally the right kidney shrank, probably
FIGURE 2. Hydronephrosis and hydroureter; enormously dilated intestinal loops with enteroliths in the upper right abdomen JOURNAL OF CLINICAL ULTRASOUND
MEGALOURETHRA AND INTRALUMINAL ENTEROLITHIASIS
from persisting incomplete infravesical obstruction. Intraluminal calcifications and bowel dilatation caused by the reflux of urine through a fistula were the clue to the diagnosis of high imperforate anus with rectovesical f i s t ~ l a . ~All , ~the ,~ other malformations are known to be associated with megalourethra. Our patient is the first case of megalourethra and posterior stenotic urethra detected by prenatal ultrasound examination. Puncturing the cyst made the obstruction incomplete and led to an increase in the amount of amniotic fluid. The combination of anhydramnion and hydronephrosis, which is caused by a complete obstruction of the urinary tract, is highly suggestive of megalourethra, if associated with an extra-abdominal cyst-like structure. No inheritance is known.279 REFERENCES 1. Anderson S, Savader B, Barnes J , Savader S: Enterolithiasis with imperforate anus. Pediatr Radiol 18:130, 1988.
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2. Kelalis P, King LR, Belman AB: Clinical Pediatric Urology. WB Saunders, Philadelphia, 1976, p 574. 3. Lockhart JL, Reeve HR, Krueger RP, Glenn JF, Henry HH: Megalourethra. Urology 12:51, 1978. 4. Shrom SH, Cromie WJ, Duckett JW: Megalourethra. Urology 17:152, 1981. 5. Appel RA, Kaplan GW, Brock WA, Streit D: Megalourethra. J Urol 135:747, 1986. 6. Nesbitt TE: Congenital megalo-urethra. J Urol 732339, 1955. 7. Danemann A, Martin DJ: A syndrome of multiple gastrointestinal atresias with intraluminal calcification. Pediatr Radiol 8:227, 1979. 8. Guttman FM, Braun P, Garance PH, et al: Multiple atresias and a new syndrome of hereditary atresias involving the gastrointestinal tract from stomach to rectum. J Pediatr Surg 8:633, 1973. 9. Firlit CM: Megalourethra in: Urethral abnormalities. Urol Clin N A n 5:42, 1978.
Complete Prenatal Urinary Tract Obstruction Caused by Congenital Megalourethra B. Simma, MD,* I. GaBner, MD,* C. Brezinka, MD,? H. Ellemunter, MD,* and A. Kreczy, MD,S
Megalourethra is a very rare congenital malformation characterized by a dilatation of the penile urethra due to a partial or complete absence of the corpus spongiosum and the corpora cavern o ~ a . ~This ’ ~ ’disorder ~ is often associated with imperforate anus, heart defects, other anomalies of the genitourinary tract (stenotic or atretic posterior urethra, megaureter, vesical diverticula, obstruction of the ureteropelvic junction, renal agenesis or hypoplasia), and other mesenchymal rnalformation~.~*~,~ CASE REPORT
Our patient was the first child of nonconsanguinous parents. A t 16 weeks, menstrual age (MA), the patient was referred to our department because of lack of amniotic fluid. Ultrasound examination revealed large intra-abdominal fluidfilled “cysts” with peristaltic movement and anhydramnion as well as hydronephrosis and hydroureter on the left and cysts in the right kidney. Karyotyping of cells from fluid obtained by aspiration of the intra-abdominal cyst showed a normal male karyogram. A t 21/22 weeks, MA, an extra-abdominal cystlike structure between the legs and many intraluminal echogenic foci in the intra-abdominal cysts were detected for the first time (Figure 1A and B). After the extra-abdominal cyst-like structure had been punctured, further ultrasound investigations showed no cyst between the legs, but surprisingly increasing amounts of amniotic fluid. The cysts in the right kidney became larger and the kidney could not be visualized after 33 ~
~
~
From the *Departments of Paediatrics, tGynaecology and Obstetrics, and $Pathology, University Clinics of Innsbruck, Austria. For reprints contact Burkhard Simma, MD, UniversiGtsklinik fur Kinderheilkunde, Anichstrasse 35, A-6020 Innsbruck. Austria.
weeks, MA. All the other ultrasound findings remained unchanged. At 39 weeks, MA, the infant was delivered by caesarean section. Birth weight was 2260g and the Apgar scores 51718. The newborn presented with multiple malformations, including esophageal atresia, imperforate anus, and a large floppy penis with a wide cleft in the ventral surface (Figure 1C). Abdominal X-ray showed enormously enlarged intestinal loops filled with gas and fluid, multiple radiopaque shadows in the upper abdomen, and a malformed sacrum (Fig. 2). Ultrasound examination revealed echogenic foci in the dilated bowels, hydronephrosis and hydroureter of the left kidney, and absent right kidney. Contrast examination of the urinary tract made through a therapeutic left nephrostomy disclosed concomitant stenosis of the posterior urethra. In spite of mechanical ventilation, the infant developed respiratory distress due to pulmonary hypoplasia and died at the age of 27 hours. In addition to the abnormalities already known, postmortem examination also disclosed rectovesical fistula, ventricular septa1 defect, splenic duplication, and atrophic right kidney. No erectile tissue was detected by penile histology. Both the corpus spongiosum and the corpora cavernosa were completely absent as is characteristic of the fusiform type of megalourethra.
DISCUSSION
Congenital megalourethra is a rare disorder of the penile ~ r e t h r a . ~Two . ~ distinct types are k n o ~ n ~ ’The ~ , ~less ’ ~severe : scaphoid megalourethra results from a deficient corpus spongiosum, whereas the fusiform type is due to the complete absence of both the corpus spongiosum and the corpora cavernosa. The urethra consequently lacks adequate support on its dorsal and ventral 197
SIMMA ET AL.
198
FIGURE 1. (A) 21/22 weeks, MA: cyst (t
+) between the legs. (FEM = femur) (B)21/22 weeks M A : intraabdominal cyst ( + + ) with enteroliths (C) large floppy penis with a wide cleft on the ventral aspect (from dorsal).
aspects and balloons during micturition,2,6thus causing an obstruction of urinary flow. Since the first description of a megalourethra by Nesbitt in 1955,6 11 cases of fusiform type megalourethra have been reported; all of them were associated with other severe mesenchymal a n ~ m a l i e s , ~ >such * ’ ~ ,as ~ upper urinary and gastrointestinal tract abnormalities (renal agenesis or hypoplasia, obstruction of the ureteropelvic junction, megaureter, stenotic or atretic posterior urethra, gastrointestinal stenosis, or atresia), deficiencies of abdominal muscles, and imperforate anus with rectourethral fistula. Fusiform megalourethra has a poorer prognosis226 than the scaphoid type; 9 of 11 patients died as newborns from serious associated malformations. No histopathological documentation of the penis was available for the 2 survivors.435 Enteroliths are intraluminal calcified meconium and may be caused by the mixing of meconium and urine due to a rectourinary fi~tu1a.l.~ Intraluminal calcifications associated with multiple gastrointestinal atresias are more frequently observed; their cause is still uncleare8 Enteroliths are demonstrable by plain X-radiography and ultrasound. In our patient the anhydramnion in combination with hydronephrosis suggested a complete obstruction of the urinary tract. At 22 weeks,
MA, ultrasound revealed a cyst-like structure between the legs (=megalourethra). “Cyst” puncture was followed by an increase in amniotic fluid. Finally the right kidney shrank, probably
FIGURE 2. Hydronephrosis and hydroureter; enormously dilated intestinal loops with enteroliths in the upper right abdomen JOURNAL OF CLINICAL ULTRASOUND
MEGALOURETHRA AND INTRALUMINAL ENTEROLITHIASIS
from persisting incomplete infravesical obstruction. Intraluminal calcifications and bowel dilatation caused by the reflux of urine through a fistula were the clue to the diagnosis of high imperforate anus with rectovesical f i s t ~ l a . ~All , ~the ,~ other malformations are known to be associated with megalourethra. Our patient is the first case of megalourethra and posterior stenotic urethra detected by prenatal ultrasound examination. Puncturing the cyst made the obstruction incomplete and led to an increase in the amount of amniotic fluid. The combination of anhydramnion and hydronephrosis, which is caused by a complete obstruction of the urinary tract, is highly suggestive of megalourethra, if associated with an extra-abdominal cyst-like structure. No inheritance is known.279 REFERENCES 1. Anderson S, Savader B, Barnes J , Savader S: Enterolithiasis with imperforate anus. Pediatr Radiol 18:130, 1988.
VOL. 20. NO. 3, MARCH/APRIL 1992
199
2. Kelalis P, King LR, Belman AB: Clinical Pediatric Urology. WB Saunders, Philadelphia, 1976, p 574. 3. Lockhart JL, Reeve HR, Krueger RP, Glenn JF, Henry HH: Megalourethra. Urology 12:51, 1978. 4. Shrom SH, Cromie WJ, Duckett JW: Megalourethra. Urology 17:152, 1981. 5. Appel RA, Kaplan GW, Brock WA, Streit D: Megalourethra. J Urol 135:747, 1986. 6. Nesbitt TE: Congenital megalo-urethra. J Urol 732339, 1955. 7. Danemann A, Martin DJ: A syndrome of multiple gastrointestinal atresias with intraluminal calcification. Pediatr Radiol 8:227, 1979. 8. Guttman FM, Braun P, Garance PH, et al: Multiple atresias and a new syndrome of hereditary atresias involving the gastrointestinal tract from stomach to rectum. J Pediatr Surg 8:633, 1973. 9. Firlit CM: Megalourethra in: Urethral abnormalities. Urol Clin N A n 5:42, 1978.
