2000-05-25-14 Cloacal dysgenesis sequence © Jeanty www.thefetus.net/
Cloacal dysgenesis sequence
Philippe Jeanty, MD, PhD
Definition: Association of an imperforate anus with confluence of the rectum, vagina, and bladder in a urogenital sinus.
Etymology: Cloaca = sewer in Latin.
Synonyms: Anorectal anomalies, persistent cloaca, cloacal malformations.
Incidence: Cloacal malformations occur in approximately 0.2:10,000 live female births. The incidence in male is not well established which may result from an ascertainment bias.
Etiology: Sporadic. Rare cases have been associated with chromosomal anomalies,6. In the mouse, a similar type of anomalies occur with mutations of the Hoxa-13 and Hoxd-13 and Etretinate, a synthetic retinoid can cause similar anomalies.
Diagnosis: The typical appearance is that of a pelvic fluid-filled structure, whose appearance depends on the anatomy involved and the gestational age,. In the first trimester, the main finding may be dilated loops of bowel, then megacystis, ascites and oligo/anhydramnios occurs when no external opening is present. The perineum is smooth with absence of anal, urethral, and/or vaginal openings. The labia majora and minora may be absent in females and the scrotum and penis may be absent or hypoplastic in males,,.
Cloacal dysgenesis with vesico-rectal fistula (courtesy Peter Twining, Nottingham, UK)
Differential diagnosis: Obstructive uropathy, but a large bladder should be visible and Vacterl.
Associated anomalies: cardiac, pulmonary (hypoplastic lungs), renal (renal agenesis, dysplasia, hydronephrosis, hydroureters), gastrointestinal (intraluminal colonic calcifications) skeletal and vertebral anomalies, growth restriction, single umbilical artery9.
Prognosis: in cases with no outlet of the urine into the amniotic cavity, the prognosis is fatal due to lung hypoplasia, but there are exceptions7. Among those surviving to surgery, in a large series of 141 patients:
· 82 have spontaneous bowel movements and satisfactory control,
· 38 use enemas to evacuate,
· 9 have a colostomy,
· 7 have fecal soiling, and
· 5 are too recently operated to evaluate.
Regarding urinary control,
· 83 void spontaneously,
· 40 catheterize to empty,
· 4 have urinary diversion,
· 1 has a continent diversion,
· 5 patients are wet, and
· 8 are too recently operated to judge11.
Twenty-four patients are now adults, 17 of who have experienced coitus and 7 have not. Seven have had babies, all except one by cesarean section11. Others have also reported normal vaginal deliveries.
Management: Prenatal: in the absence of amniotic fluid, the pregnancy can be managed as non-viable. Postnatally, the management depends on the type of anomalies and associated malformations.
 Dodson JL, Ferrer FA, Jackman SV, Blakemore KJ, Docimo SG Cloacal outlet obstruction with an ectopic ureter. Urology (Online) 2000 May 1;55(5):775
 Chen CP, Chern SR, Lee CC, Town DD Isochromosome 18q in a fetus with congenital megacystis, intra-uterine growth retardation and cloacal dysgenesis sequence. Prenat Diagn 1998 Oct;18(10):1068-74
 Warot X, Fromental-Ramain C, Fraulob V, Chambon P, Dolle P Gene dosage-dependent effects of the Hoxa-13 and Hoxd-13 mutations on morphogenesis of the terminal parts of the digestive and urogenital tracts. Development 1997 Dec;124(23):4781-91
 Mesrobian HG, Sessions RP, Lloyd RA, Sulik KK Cloacal and urogenital abnormalities induced by etretinate in mice. J Urol 1994 Aug;152(2 Pt 2):675-8
 Zaccara A, Gatti C, Silveri M, Rivosecchi M, Bilancioni E, Spina V, Giorlandino C, De Gennaro M, Bagolan P Persistent cloaca: are we ready for a correct prenatal diagnosis? Urology (Online) 1999 Aug;54(2):367
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 Liang X, Ioffe OB, Sun Cloacal dysgenesis sequence: observations in four patients including three fetuses of second trimester gestation. Pediatr Dev Pathol 1998 Jul-Aug;1(4):281-8
 Carroll SG, Hyett J, Eustace D, Seller MJ, Nicolaides KH Evolution of sonographic findings in a fetus with agenesis of the urethra, vagina, and rectum. Prenat Diagn 1996 Oct;16(10):931-3
 Murr MM, Waziri MH, Schelper RL, Abu-Youself M Case of multivertebral anomalies, cloacal dysgenesis, and other anomalies presenting prenatally as cystic kidneys. Am J Med Genet 1992 Apr 1;42(6):761-5
 Qureshi F, Jacques SM, Yaron Y, Kramer RL, Evans MI, Johnson MP Prenatal diagnosis of cloacal dysgenesis sequence: differential diagnosis from other forms of fetal obstructive uropathy. Fetal Diagn Ther 1998 Mar-Apr;13(2):69-74
 Hendren WH Cloaca, the most severe degree of imperforate anus: experience with 195 cases. Ann Surg 1998 Sep;228(3):331-46
 Ljubic A, Sulovic V, Stankovic A, Cvetkovic A Cloacal dysgenesis and vaginal delivery. J Gynecol Obstet Biol Reprod (Paris) 1993;22(4):417-8