Megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) is a rare congenital disorder charaeterized by a diluted, non- obstructive urinary bladder and hypoperistalsis of the gastro- intestinal tract, which is considered lethal. About 90 patients have been reported, predominantly female. We present the case of a female newborn with MMIHS in whom antenatal ultrasound was suggestive for the diagnosis, which was confirmed after delivery. Diagnostic features by antenatal ultrasound are described.
Key words: MEGACYSTIS; MIOROCOLON; HYPOPERISTALSIS
Megacystis-microcolon-intestinal hy poper istals is syndrome (MMIHS) is characterized by abdominal distension, a dilated, non- obstructive urinary bladder, microcolon and bypoperistalsis of the gastrointestinal (GI) tract. Since Rerdon and colleagues first described it in 1976, about 90 cases have been reported in the literature1. Prenatal diagnosis is difficult and a genetic locus has not yet been identified2.
At a gestational age of 36 weeks 6 days, a female infant was born to a primiparous mother. There was no consanguinity. At gestational age ol 30 weeks the ultrasound scan revealed an increased amount of amniotic fluid with a markedly distended bladder extending up to the diaphragm in the absence of dilatation of the ureters and renal pelvis (Figure 1). Amniocentesis was performed, which showed a normal karyotype (46XX).
During labor the fetus passed meconium. Physical examination showed a distended abdomen. Abdominal ultrasound imaging revealed an enlarged urinary bladder with bilateral hydronephrosis. A urethral catheter was inserted, which drained 600 ml of urine.
A water-soluble contrast enema showed a microcolon and a study of the upper (71 showed a malrotation and hypoperistalsis of the distal esophagus and stomach.
During admittance meconium did not pass and enterai feeding was not possible because of vomiting and persistent bilious drainage. On the seventh day of life a laparotomy was performed. The findings included dilated small intestine with a sudden change in distension and a malrotation. An ileostomy was made. Diagnostic biopsies were taken from different locations of the intestines and bladder.
Total patenterai nutrition (TPN) was started. A trial with different prokinetics was unsuccessful. The ileostomy also failed to pass fcces.
The histology of the intestines and the bladder showed normal ganglionosis, a very thin muscular layer, vacuolic degeneration, collagen proliferation and a decreased coloring of actin. These findings confirmed our suspected diagnosis of MMIHS. At 5 weeks TPN was discontinued and at 6 weeks of age she died.
Figure 1 Antenatal ultrasound image
Although the etiology of MMIHS is unknown, no abnormalities in ganglionic cells are found and the possibility of a smooth muscle myopathy is considered5.
MMIHS is the most severe form of functional intestinal obstruction3. Although a genetic locus has not yet been identified, an autosomal recessive inheritance has been suggested2,3.
Treatment is supportive and involves an ileostomy to defunction the colon, with TPN. MMIHS is usually lethal within the first year of life, typically due to TPN complications, renal failure and sepsis. Multivisceral transplantation as an experimental treatment has been reported in three patients with TPN-induced liver failure, of whom only one survived and was living at home with a functional graft 17 months after transplantation4.
Prenatal diagnosis of MMIHS is possible by antenatal ultrasound and needed for early postnatal investigations. We suggest that the triad of a female fetus with an enlarged urinary bladder and normal amniotic fluid is pathognomonic for MMIHS. In males with fetal megacystis, the most likely diagnosis is early urethral obstruction syndrome. Clinical genetic counseling is indicated for further pregnancies. We reviewed the tape of an ultrasound examination of this case at a gestational age of 16 weeks by the referring hospital. These images demonstrated a slightly increased amount of amniotic fluid, a normal-sized bladder and the absence of hydronephrosis, but a huge dilated stomach. These observations have to be taken into account when counseling parents for the exclusion by ultrasound of the described anomaly in future pregnancies at an earlier stage.
1. Berdon WE, Baker DH, Blane WA, et al. Megacystistnicrocolon- intestinal hypoperistalsis syndrome: A new cause of intestinal obstruction in the new horn. Report of radiological findings in five newborn girls. Am J Roentgeno! 1976;126:957-64
2. White SM, Chamberlain P, Hitchcock R, et al. Megacystismicrocolon-intestinal hypoperistalsis syndrome: the difficulties with antenatal diagnosis. case report and review of the literature. Prenat Diagn. 2000;20:697-700
3. Rolle U, O’Briain S, Pearl RH, Puri P. Megacystis- microcolonintestinal hypoperistalsis syndrome: evidence of intestinal myopathy. Pediatr Surg Int 2002;18:2-5
4. Masetti M, Rodriguez MM, Thompson JF, et al. Multivisceral transplantation for megacystis microcolon intestinal hypoperistalsis syndrome. Transplantation 1999;68:228-32
S. C. A. T. Verbruggen1, R. M. H. Wijnen2 and P. van den Berg3
1 Department of Pediatrics, Erasmus MC Sophia Children’s Hospital, Rotterdam, The Netherlands
2 Department of Pediatric Surgery, UMC St. Radboud, Nijmegen, The Netherlands
3 Department of Gynecology, UMC St. Radboud, Nijmegen, The Netherlands
Correspondence: Dr R. M. H. Wijnen, Department of Pediatric Surgery, UMCN St. Radboud, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
Received 12-11-03 Revised 22-12-03 Accepted 06-02-04
Copyright CRC Press Aug 2004