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Pediatric Imperforate Anus Clinical Presentation

  • Author: Nelson G Rosen, MD, FACS, FAAP; Chief Editor: Carmen Cuffari, MD  more...
 
Updated: Nov 17, 2014
 

History

Prenatal ultrasonography examination findings are often normal, although the polyhydramnios or intraabdominal cysts may suggest imperforate anus with associated hydrocolpos or hydronephrosis.

Newborns with imperforate anus are usually identified upon the first physical examination. Malformations in newborns that are missed upon initial examination are often discovered within 24 hours when the newborn is observed to have distention and has failed to pass meconium and a more thorough examination is performed.

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Physical

During a thorough physical examination, attention should be focused on the abdomen, genitals, rectum, and lower spine.[3]

The umbilicus should be examined for the absence of an umbilical artery (2-vessel cord), which may suggest an absent kidney. The abdomen should be palpated for masses, which may include a dilated kidney, bladder, hydrocolpos, ectopic kidney, duplication, or other cystic structure.

In males, the testicles must be palpated in the scrotum. The perineum is then examined. Perineal fistulas are diagnosed upon discovery of openings on the perineum, meconium or mucus in a small strip running up into the scrotal median raphe, a perineal groove, or a bucket-handle malformation in the anal dimple skin. If no opening is present, urine is obtained for study, and the child is observed for 24 hours.

In females, a perineal fistula can be directly identified as a small opening on the perineum. If none is present, the labia are separated to search for a vestibular fistula. A fourchette fistula is a type of vestibular fistula that straddles the spectrum of malformation between perineal and vestibular; it is characterized by wet mucosa of the vestibule anteriorly and a dry anoderm posteriorly at the junction of the vestibule and perineum (see the image below).

Fourchette fistula. This malformation is somewhere Fourchette fistula. This malformation is somewhere halfway between perineal fistula and vestibular fistula. The fistula has a wet vestibular mucosal lining on its anterior half, but the posterior half is dry perineal skin.

If no fistula is visible and only one opening between shortened labia is observed, the child has a cloaca (see image below).

Cloaca. This is the classic appearance of a girl w Cloaca. This is the classic appearance of a girl with a cloacal malformation with a single perineal orifice. The genitals appear quite short, which is a finding consistent with cloaca.

If the child has a normal urethra and no vestibular fistula, she may have imperforate anus without fistula. If she appears to have trisomy 21, the likelihood increases that she does not have a fistula. Girls with normal urethra and no visible fistula are observed for 24 hours to allow a perineal fistula to present before operation is required. This waiting period is beneficial in differentiating between children with perineal fistula who may be effectively treated using only a minimal anoplasty from those who require colostomy with further evaluation using distal colostography. Examples of colostography findings are shown in the images below.

Distal colostogram, posteroanterior view. The init Distal colostogram, posteroanterior view. The initial phase of augmented-pressure distal colostography aims to determine where the colostomy was placed in the colon and how much colon is available for pull-through, without taking down the colostomy.
Distal colostogram, lateral view. This image shows Distal colostogram, lateral view. This image shows the second phase of distal colostography, in which the patient is placed in the lateral position. A radio-opaque marker is clearly visible in the lower right side of the image, marking the muscle complex on the skin. This image shows that the rectal pouch joins the urinary tract at the level of the bulbar urethra, a relatively common malformation in boys.

The remainder of physical examination is focused associated malformations. Cardiovascular malformations occur in 12-22% of patients. The most common lesions are tetralogy of Fallot and ventricular septal defects. Transposition of the great arteries and hypoplastic left heart syndrome have been reported but are rare.

Many GI malformations have been described in association with imperforate anus. As many as 10% of patients have tracheoesophageal abnormalities.[4] Duodenal obstruction due to annular pancreas or duodenal atresia occurs in a small percentage of patients. Malrotation with Ladd bands that causes obstruction has also been described. Hirschsprung disease has been well described in association with imperforate anus, although the incidence of this combined condition is unknown. Constipation is common.

The association of imperforate anus and vertebral anomalies has been recognized for many years. Patients with high lesions have an increased risk of this association. Lumbosacral anomalies predominate and occur in approximately one third of patients with imperforate anus.[5]

The frequency of spinal dysraphism (evaluated with ultrasonography or MRI) had been thought to increase with the severity of the lesion, with higher malformations having greater frequency than lower malformations. Several studies have disputed this and have even shown higher incidence of spinal malformations in children with low malformations. The most common type of dysraphism is tethered spinal cord, which is present in as many as 35% of patients. The normal spinal cord terminates between the first and second lumbar vertebral bodies. In patients with a tethered spinal cord, the cord ends lower in the lumbar spine. Cord lipomas and syringohydromyelia are also common. All lumbosacral spinal malformations negatively affect the child's prognosis with respect to urinary and fecal incontinence.

Currarino described a triad of sacral defect, presacral mass, and imperforate anus.[6] All patients with an anorectal malformation must be screened for these vertebral abnormalities in the newborn period using sacral radiography and lumbosacral spinal ultrasonography. As many as one half of patients with anorectal malformations have urologic abnormalities. Urinary anomalies are more common in patients with more complex lesions. Improved imaging studies have provided the ability to document an increased range of abnormalities. Mild hydronephrosis is the most common abnormal ultrasonography finding. Vesicoureteric reflux is also a frequent finding, followed by renal agenesis and dysplasia. Cryptorchidism reportedly occurs in 3-19% of males.

Vaginal and uterine abnormalities are common. Bicornate uterus and uterus didelphys occur in 35% of female patients with imperforate anus. A vaginal septum is the most common vaginal abnormality and is seen in as many as one half of girls born with a cloacal malformation. Vaginal duplication and agenesis have also been reported. Vaginal agenesis may be associated with ipsilateral absent ovary and kidney.

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Causes

Although the precise embryologic defect that causes anorectal malformations has not been determined, cloacal membrane formation and subsequent breakdown into urogenital and anal openings should occur by 8 weeks' gestation. Defects in the formation or shape of the posterior urorectal septum account for many of the described abnormalities of imperforate anus. Müllerian ducts appear after this critical period; how they are incorporated into this development is unclear.

No known risk factors predispose a person to have a child with imperforate anus, which should be clearly emphasized to parents of affected children who may harbor feelings of guilt. A genetic linkage is sometimes present. Most cases of imperforate anus are sporadic without a family history of the condition, but some families have several children with malformations. Genetic studies are ongoing.

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Contributor Information and Disclosures
Author

Nelson G Rosen, MD, FACS, FAAP Assistant Professor of Surgery and Pediatrics, Albert Einstein College of Medicine; Attending Pediatric Surgeon and Director, Pediatric Trauma Center, Department of Pediatric General Surgery, Schneider Children's Hospital

Nelson G Rosen, MD, FACS, FAAP is a member of the following medical societies: American Academy of Pediatrics, American College of Surgeons, American Pediatric Surgical Association, American Trauma Society, Association of Military Surgeons of the US, Eastern Association for the Surgery of Trauma, Canadian Association of Pediatric Surgeons

Disclosure: Nothing to disclose.

Specialty Editor Board

Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

Carmen Cuffari, MD Associate Professor, Department of Pediatrics, Division of Gastroenterology/Nutrition, Johns Hopkins University School of Medicine

Carmen Cuffari, MD is a member of the following medical societies: American College of Gastroenterology, American Gastroenterological Association, North American Society for Pediatric Gastroenterology, Hepatology and Nutrition, Royal College of Physicians and Surgeons of Canada

Disclosure: Received honoraria from Prometheus Laboratories for speaking and teaching; Received honoraria from Abbott Nutritionals for speaking and teaching.

Chief Editor

Carmen Cuffari, MD Associate Professor, Department of Pediatrics, Division of Gastroenterology/Nutrition, Johns Hopkins University School of Medicine

Carmen Cuffari, MD is a member of the following medical societies: American College of Gastroenterology, American Gastroenterological Association, North American Society for Pediatric Gastroenterology, Hepatology and Nutrition, Royal College of Physicians and Surgeons of Canada

Disclosure: Received honoraria from Prometheus Laboratories for speaking and teaching; Received honoraria from Abbott Nutritionals for speaking and teaching.

Additional Contributors

Hisham Nazer, MB, BCh, FRCP, , DTM&H Professor of Pediatrics, Consultant in Pediatric Gastroenterology, Hepatology and Clinical Nutrition, University of Jordan Faculty of Medicine, Jordan

Hisham Nazer, MB, BCh, FRCP, , DTM&H is a member of the following medical societies: American Association for Physician Leadership, Royal College of Paediatrics and Child Health, Royal College of Surgeons in Ireland, Royal Society of Tropical Medicine and Hygiene, Royal College of Physicians and Surgeons of the United Kingdom

Disclosure: Nothing to disclose.

Acknowledgements

Daniel A Beals, MD Attending Staff, Cornerstone Pediatric Surgery

Daniel A Beals, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Physicians, American Pediatric Surgical Association, American Society for Bioethics and Humanities, Kentucky Medical Association, Society for Fetal Urology, Society of Critical Care Medicine, and Southeastern Surgical Congress

Disclosure: Nothing to disclose.

References
  1. Pena A, Devries PA. Posterior sagittal anorectoplasty: important technical considerations and new applications. J Pediatr Surg. 1982 Dec. 17(6):796-811. [Medline].

  2. Beudeker N, Broadis E, Borgstein E, Heij HA. The hidden mortality of imperforate anus. Afr J Paediatr Surg. 2013 Oct-Dec. 10(4):302-6. [Medline].

  3. Mirza B, Ijaz L, Saleem M, Sharif M, Sheikh A. Anorectal malformations in neonates. Afr J Paediatr Surg. 2011 May-Aug. 8(2):151-4. [Medline].

  4. Rosenbaum DG, Kasdorf E, Renjen P, Brill P, Kovanlikaya A. Sling left pulmonary artery with patent type IIA tracheobronchial anomaly and imperforate anus. Clin Imaging. 2014 Sep-Oct. 38(5):743-6. [Medline].

  5. Stathopoulos E, Muehlethaler V, Rais M, Alamo L, Dushi G, Frey P, et al. Preoperative assessment of neurovesical function in children with anorectal malformation: association with vertebral and spinal malformations. J Urol. 2012 Sep. 188(3):943-7. [Medline].

  6. Lee SC, Chun YS, Jung SE, et al. Currarino triad: anorectal malformation, sacral bony abnormality, and presacral mass--a review of 11 cases. J Pediatr Surg. 1997 Jan. 32(1):58-61. [Medline].

  7. [Guideline] Bischoff A, Levitt MA, Bauer C, Jackson L, Holder M, Pena A. Bowel management for fecal incontinence in patients with anorectal malformations. J Pediatr Surg. 2009 Jun. 44(6):1278-83. [Medline].

  8. Tong QS, Tang ST, Pu JR, Mao YZ, Wang Y, Li SW, et al. Laparoscopically assisted anorectal pull-through for high imperforate anus in infants: intermediate results. J Pediatr Surg. 2011 Aug. 46(8):1578-86. [Medline].

  9. Pena A. Anorectal malformations. Semin Pediatr Surg. 1995 Feb. 4(1):35-47. [Medline].

  10. Albanese CT, Jennings RW, Lopoo JB, et al. One-stage correction of high imperforate anus in the male neonate. J Pediatr Surg. 1999 May. 34(5):834-6. [Medline].

  11. Chait PG, Shandling B, Richards HM, Connolly BL. Fecal incontinence in children: treatment with percutaneous cecostomy tube placement--a prospective study. Radiology. 1997 Jun. 203(3):621-4. [Medline].

  12. Chatterjee SK. The value of inversion radiography (invertography) in the assessment of anorectal malformation. J Indian Med Assoc. 1976 Dec 16. 67(12):265-7. [Medline].

  13. De Filippo RE, Shaul DB, Harrison EA, et al. Neurogenic bladder in infants born with anorectal malformations: comparison with spinal and urologic status. J Pediatr Surg. 1999 May. 34(5):825-7; discussion 828. [Medline].

  14. [Guideline] Dick EA, Patel K, Owens CM, De Bruyn R. Spinal Ultrasound in Infants. Br J Radiol. April 2002. 75:384-392. [Medline]. [Full Text].

  15. Flageole H, Fecteau A, Laberge JM, Guttman FM. Hirschsprung's disease, imperforate anus, and Down's syndrome: a case report. J Pediatr Surg. 1996 Jun. 31(6):759-60. [Medline].

  16. Fraser R. Imperforate anus: nutritional care. Paediatr Nurs. 1996 Apr. 8(3):16-8. [Medline].

  17. Georgeson KE, Inge TH, Albanese CT. Laparoscopically assisted anorectal pull-through for high imperforate anus--a new technique. J Pediatr Surg. 2000 Jun. 35(6):927-30; discussion 930-1. [Medline].

  18. Golonka NR, Haga LJ, Keating RP, et al. Routine MRI evaluation of low imperforate anus reveals unexpected high incidence of tethered spinal cord. J Pediatr Surg. July 2002. 37:966-969. [Medline].

  19. Heikenen JB, Werlin SL, Di Lorenzo C, et al. Colonic motility in children with repaired imperforate anus. Dig Dis Sci. 1999 Jul. 44(7):1288-92. [Medline].

  20. Hendren WH. Cloaca, the most severe degree of imperforate anus: experience with 195 cases. Ann Surg. 1998 Sep. 228(3):331-46. [Medline].

  21. Hong AR, Acuna MF, Pena A, et al. Urologic injuries associated with repair of anorectal malformations in male patients. J Pediatr Surg. 2002 Mar. 37(3):339-44. [Medline].

  22. Levitt MA, Patel M, Rodriguez G. The tethered spinal cord in patients with anorectal malformations. J Pediatr Surg. 1997. 32(3):462-8.

  23. Levitt MA, Patel M, Rodriguez G, et al. The tethered spinal cord in patients with anorectal malformations. J Pediatr Surg. 1997 Mar. 32(3):462-8. [Medline].

  24. Levitt MA, Stein DM, Pena A. Gynecologic concerns in the treatment of teenagers with cloaca. J Pediatr Surg. 1998 Feb. 33(2):188-93. [Medline].

  25. Moss RL. The failed anoplasty: successful outcome after reoperative anoplasty and sigmoid resection. J Pediatr Surg. 1998 Jul. 33(7):1145-7; discussion 1147-8. [Medline].

  26. Nagar H, Weiss J, Kessler A. Bacterial orchitis in a baby with imperforate anus. Pediatr Radiol. 1998 Sep. 28(9):705. [Medline].

  27. Pena A. Total urogenital mobilization--an easier way to repair cloacas. J Pediatr Surg. 1997. 32(2):263-8. [Medline].

  28. Pena A, Amroch D, Baeza C, et al. The effects of the posterior sagittal approach on rectal function (experimental study). J Pediatr Surg. 1993 Jun. 28(6):773-8. [Medline].

  29. Pena A, el Behery M. Megasigmoid: a source of pseudoincontinence in children with repaired anorectal malformations. J Pediatr Surg. 1993 Feb. 28(2):199-203. [Medline].

  30. Rich MA, Brock WA, Pena A. Spectrum of genitourinary malformations in patients with imperforate anus. Pediatric Surg Intl. 1988. 3:110-113.

  31. Rosen NG, Hong A, Soffer S. Recto-vaginal fistula: a common diagnostic error with significant consequences in girls with anorectal malformations. J Pediatr Surg. 2002. 37(7):961-5.

  32. Shaul DB, Harrison EA. Classification of anorectal malformations--initial approach, diagnostic tests, and colostomy. Semin Pediatr Surg. 1997 Nov. 6(4):187-95. [Medline].

  33. Soffer SZ, Rosen NG, Hong AR, et al. Cloacal exstrophy: a unified management plan. J Pediatr Surg. 2000 Jun. 35(6):932-7. [Medline].

  34. Torres R, Levitt MA, Tovilla JM, Rodriguez G, Pena A. Anorectal malformations and Down's syndrome. J Pediatr Surg. 1998 Feb. 33(2):194-7. [Medline].

  35. Tsakayannis DE, Shamberger RC. Association of imperforate anus with occult spinal dysraphism. J Pediatr Surg. 1995 Jul. 30(7):1010-2. [Medline].

  36. Wang C, Lin J, Lim K. The use of augmented-pressure colostography in imperforate anus. Pediatr Surg Int. 1997 Jul. 12(5-6):383-5. [Medline].

 
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Distal colostogram, posteroanterior view. The initial phase of augmented-pressure distal colostography aims to determine where the colostomy was placed in the colon and how much colon is available for pull-through, without taking down the colostomy.
Distal colostogram, lateral view. This image shows the second phase of distal colostography, in which the patient is placed in the lateral position. A radio-opaque marker is clearly visible in the lower right side of the image, marking the muscle complex on the skin. This image shows that the rectal pouch joins the urinary tract at the level of the bulbar urethra, a relatively common malformation in boys.
Bucket-handle malformation. The appearance of a band of skin overlying the sphincteric muscle complex is a common sign in a child born with imperforate anus and perineal fistula.
String-of-pearls malformation. This image shows white mucoid material within a perineal fistula. The fistula frequently extends anteriorly up the scrotum's median raphe.
Cloaca. This is the classic appearance of a girl with a cloacal malformation with a single perineal orifice. The genitals appear quite short, which is a finding consistent with cloaca.
Fourchette fistula. This malformation is somewhere halfway between perineal fistula and vestibular fistula. The fistula has a wet vestibular mucosal lining on its anterior half, but the posterior half is dry perineal skin.
 
 
 
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