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12-Year-Old Girl With ConstipationAnd Rectal Bleeding

Arvind Srinath, MD,* Danielle Wendel, MD, Geoffrey Bond,

MD, Mark Lowe, MDx

PresentationA 12-year-old girl with a history of well-controlled consti-pation presents to the emergency department after havingan uncomfortable, large, nonbloody bowel movement athome followed by sacral numbness and bright red bloodseeping out of her rectum. Her review of systems is re-markable for 1 to 2 soft bowel movements per day withoccasional cramping, painful defecation (dyschezia), andsensation of incomplete evacuation (tenesmus). She ispremenarchal and denies any history of easy bleeding orbruising or trauma. She additionally denies constitutionalsymptoms, oral ulcers, heartburn, or a history of anemia.

Her family history is remarkable for food allergies anddeveloping glioblastoma multiforme on both sides of thefamily. There is no family history of inammatory bowel dis-ease, polyps, coagulopathy, or rheumatologic conditions.

Vital signs are as follows: heart rate, 124 beats perminute; respiratory rate, 20 breaths per minute; bloodpressure, 117/72 mm Hg; temperature, 98.8F (37.1C);and oxygen saturation, 100% on room air. Her weight is36.4 kg (15th percentile), height is 153 cm (40th per-centile), and body mass index is 15.1 (10th percentile).Physical examination reveals a soft, benign abdomen with-out any masses or organomegaly. Perianal examination isnotable for gross external blood on the perianal skin with-out external ssures, hemorrhoids, lesions, uctuance, orpalpable masses. There is no palpable stool in the rectalvault. The sacrum does not have any overlying skinchanges or palpable masses. There is no other evidenceof bleeding, bruising, or petechiae. The rest of the phys-ical examination ndings are normal.

Laboratory examination reveals a hemoglobin level of10.5 g/dL (105 g/L) (mean corpuscular volume, 90.0mm3; red blood cell distribution width, 13.8). The restof her complete blood cell count was remarkable fora white blood cell count of 15,800/mL (15.8 109/L)(87% neutrophils and 10% lymphocytes) and platelet countof 261 103/mL (261 109/L).

Figure 1. Lymphoid hyperplasia throughout colon (arrows).

Author Disclosure

Drs Srinath, Wendel, Bond, and Lowe have disclosed no

financial relationships relevant to this article. This

commentary does contain discussion of unapproved/

investigative use of a commercial product/device.

*Pediatric Gastroenterology Fellow, Childrens Hospital of Pittsburgh, Pittsburgh, PA.Pediatric Resident, Childrens Hospital of Pittsburgh, Pittsburgh, PA.Assistant Professor in Transplant Surgery, Transplant Director, University of Pittsburgh, Pittsburgh, PA.xChief, Division of Pediatric Gastroenterology, Childrens Hospital of Pittsburgh, Pittsburgh, PA.

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Because of her rectal bleeding, tachycardia, and mildanemia, the patient is admitted for observation and fur-ther evaluation. During the next 24 hours, she has onepainless melanotic stool, and her hemoglobin level de-creases 2 g/dL (20 g/L) to 8.5 mg/dL (85 g/L) (meancorpuscular volume, 89.4 mm3; red blood cell distribu-tion width, 13.7).

Further laboratory tests reveal a reticulocyte count of1.2%, an international normalized ratio of 1.1, a partialthromboplastin time of 38.1 seconds, and negative vonWillebrand study results. The patients albumin, erythro-cyte sedimentation rate, and urinalysis results are normal.A Meckel scan is unremarkable. Subsequent endoscopyand colonoscopy document a attened rectum. How-ever, gross blood in the rectum prevents optimal visual-ization of the mucosa. The rest of the colon is remarkablefor lymphoid hyperplasia (Figure 1).

Subsequent abdominal computed tomography (CT)(Figure 2) with contrast reveals the diagnosis.

Diagnosis: Rectal Duplication CystA roughly 5-cm3 heterogeneous uid collection locatedanterior to the sacrum and posterior to the anal canaland pushing the anal canal anteriorly is discovered on

CT examination. The presence of gas around and withinthemass is concerning for bowel wall disruption (Figure 3).Follow-up pelvic magnetic resonance imaging (MRI)reveals a well-circumscribed, heterogeneous presacralmass in the pelvis that is contiguous with the rectal walland compresses the rectum (Figure 4). There is also anincidental Tarlov cyst, which is a perineural cyst thatcontains cerebrospinal uid.

DiscussionRectal duplications are congenital malformations of abnor-mally closed epithelium-lined cavities whose walls consistof colonic or anorectal mucosa. Rectal duplications are ei-ther continuous or contiguous with the rectum and havea muscular coat (smooth muscle in 2 layers) and an epithe-lial lining.Most rectal duplications are cystic, although theycan be tubular, extrophic, or diverticular or occur with a cu-taneous stula (25%40% of cases) to the perineum or anus.

Rectal duplications are usually retrorectal. Their epi-thelial lining is most often colonic, although they alsocan have squamous epithelia, respiratory epithelia, gastricmucosa, or urothelial cells.

The cause of rectal duplications is unclear. Becausea great deal of embryologic activity occurs in the caudal

Figure 2. Abdominal-pelvic computed tomogram. Heteroge-neous fluid collection (blue arrow) anterior to sacrum andposterior to the anal canal. Locules of gas (red arrow) withinfluid collection raise concern for bowel wall disruption.B[bladder. Dashed arrow indicates the rectal lumen. Courtesyof Virginia Kania, DO, and Sameh Tadros, MD, MSc, Departmentof Radiology, Childrens Hospital of Pittsburgh of University ofPittsburgh Medical Center.

Figure 3. Axial view on pelvic magnetic resonance imaging.Evolving hematoma (arrow) posterior to the rectal lumen(dashed arrow).A[anterior; R[right; O[ovary. Courtesy of Virginia Kania,DO, and Sameh Tadros, MD, MSc, Department of Radiology,Childrens Hospital of Pittsburgh of University of PittsburghMedical Center.

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region, multiple theories on abnormal development inthis area have been proposed to explain their occurrence.The enteric bud theory hypothesizes that a part of the in-testinal epithelium protrudes outwards but still maintainsconnection with the bowel lumen. Another theory pro-poses the embryonic gastrointestinal tract rapidly enlargesand outgrows the coelomic cavity; this occurrence is fol-lowed by recanalization of intestinal epithelia. Lastly, itis postulated that duplications develop from an aberrationin cloacal division. None of these theories explain the po-tential presence of heterotopic gastric mucosa in rectal du-plication cysts.

Rectal duplications themselves are more prevalent inwhite females and comprise 1% to 8% of intestinal dupli-cations. They can also be associated with other hindgutmalformations, such as in the Currarino triadanorectalmalformation, anterior sacral defect, and presacral mass(teratomas, meningoceles, dermoid cyst, and entericcyst). Rectal duplications can be but are rarely associatedwith cardiac malformations.

Rectal duplications can present at any age. They are of-ten discovered before age 2 years but may not present untiladulthood. The main clinical features include rectal pain,rectal discomfort, obstruction, a prolapsing rectal mass,bleeding, and/or sciatic pain. However, the clinical

presentation of rectal duplications depends on multiplefactors, such as size, site, presence of infection, presenceof gastric mucosa, and type of communication (internalto rectal lumen or external). In addition, rectal dup-lications can compress the rectum and adjacent visceraand lead to rectal prolapse. The presence of ectopic gas-tric mucosa could lead to bleeding, perianal stula,perianal irritation, or recalcitrant perianal infection. Rec-tal bleeding can also occur because of irritation or in-fection of the cyst itself, even without the presence ofgastric mucosa.

Potential complications of rectal duplications includesecondary infection or rupture or carcinomatous de-generation. The incidence of carcinomatous degenera-tion is 12% to 18% in adults, with none reported to datein children.

Differential DiagnosisThe differential diagnosis for rectal duplications includesteratoma, dermoid cyst, anterior sacral meningocele, andhematoma. Rectal duplications can also be misdiagnosedas hemorrhoids, rectal prolapse, or polyps. The latter 3conditions fall under the general differential diagnosisfor lower gastrointestinal bleeding in an adolescentinaddition to infectious enterocolitis, Meckel diverticulum,inammatory bowel disease, anal ssure, perianal strepto-coccal cellulitis, intussusception, rectal trauma, vascularmalformation, and solitary rectal ulcer.

DiagnosisThe diagnosis of rectal duplication requires a high indexof suspicion. On rectal examination, one may palpate adiverticular opening. Proctoscopy can aid in visualizinga diverticular opening. In addition, barium enema,stulogram, ultrasonography, CT, and MRI are helpfulto delineate the anatomy and the extent of the duplica-tion. Abdominopelvic CT is particularly helpful to ruleout an anterior meningocele associated with a vertebraldefect. Endoscopic ultrasonography may be helpful aswell. Even if gastric mucosa is present, rectal duplicationsmay have false-negative Meckel scan results because of ei-ther the sensitivity and specicity of the test itself or ob-scuration by physiologic tracer activity in the bladder.

ManagementThe treatment of rectal duplications depends on their siteand presence or absence of infection. Surgical resection isthe main treatment. The main risk of surgery includesanal sphincter injury from the rectal duplication lesion it-self or from intraoperative retraction. This injury couldlead to fecal incontinence.

Figure 4. Sagittal view on pelvic magnetic resonance imaging.Evolving hematoma (red arrows) posterior to the rectal lumen(dashed arrows). Incidental Tarlov cyst (blue arrow).B[bladder; S[pubic symphysis. Courtesy of Virginia Kania,DO, and Sameh Tadros, MD, MSc, Department of Radiology,Childrens Hospital of Pittsburgh of University of PittsburghMedical Center.

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Patient CourseSurgical exploration identied a rectal duplication cystsurrounded by low-grade inammatory tissue. The cystwas incompletely excised because the cysts marginscould not be clearly identied and the cyst was proximalto the anal sphincter. Pathologic examination of the cystrevealed colonic mucosa without ectopic mucosa withinthe cyst.

Of note, the patients Tarlov cyst was left alone. A Tar-lov cyst is a sac that contains cerebrospinal uid, locatedin the sacral region (S1-S4) of the spinal canal. The Tar-lov cyst has an unclear origin and is usually asymptomaticif less than 1.5 cm in diameter.

Although the patient tolerated surgery without com-plication, she later presented with an abscess at the sur-gical site and had to undergo a temporary sigmoidostomyafter abscess drainage, with reanastamosis 6 monthslater. She is currently doing well and passes stool with-out difculty.

Suggested ReadingDahan H, Arriv L, Wendum D, Docou le Pointe H, Djouhri H,

Tubiana JM. Retrorectal developmental cysts in adults: clinicaland radiologic-histopathologic review, differential diagnosis,and treatment. Radiographics. 2001;21(3):575584

Knudtson J, Jackson R, Grewal H. Rectal duplication. J PediatrSurg. 2003;38(7):11191120

Macpherson RI. Gastrointestinal tract duplications: clinical, patho-logic, etiologic, and radiologic considerations. Radiographics.1993;13(5):10631080

Rajah S, Ramanujam TM, Anas SR, et al. Duplication of the rec-tum: report of four cases and review of the literature. PediatrSurg Int. 1998;13(56):373376

Salameh JR, Votanopoulos KI, Hilal RE, et al. Rectal duplicationcyst in an adult: the laparoscopic approach. J Laparoendosc AdvSurg Tech A. 2002;12(6):453456

Thompson RJ, Charlton FG, Jaffray B. Acid-secreting rectal du-plication cyst with associated peptic ulcer eroding through theanal sphincters. J Pediatr Surg. 2002;37(11):E37

Summary

Rectal duplication cysts are rare, thought to be due todefects in embryologic development, and oftenassociated with other structural abnormalities.

Clues to the existence of a rectal cyst are mainly dueto bowel compression and presence of ectopic gastricmucosa within the cyst, leading to rectal bleeding.

The diagnosis of a rectal duplication cyst requiresa high index of suspicion. Confirming the diagnosiscan be difficult based on the location of the cyst.Efforts to confirm the diagnosis include digital rectalexamination, computed tomography, magneticresonance imaging, ultrasonography, and Meckel scan.

Surgical resection is the treatment of choice,especially because of the cysts potential formalignant transformation. Because of the cystsproximal location to the nerves innervating the analcanal and sphincters, surgical resection can lead tofecal incontinence.

Parent Resources from the AAP at HealthyChildren.org

English: http://www.healthychildren.org/English/health-issues/conditions/abdominal/Pages/Constipation.aspx Spanish: http://www.healthychildren.org/spanish/health-issues/conditions/abdominal/paginas/constipation.aspx English: http://www.healthychildren.org/English/family-life/health-management/Pages/When-to-Call-Your-Pediatrician.

aspx Spanish: http://www.healthychildren.org/spanish/family-life/health-management/paginas/when-to-call-your-

pediatrician.aspx

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