Meckel diverticulum acting as a lead point.

Figure 103-42. Common variants of yolk stalk malformations. A,B: Meckel diverticulum can manifest with inflammation

(diverticulitis) or hemorrhage from acid-induced ulceration. C,D: Meckel diverticulum in association with abnormal band attached

to the abdominal wall predisposing to volvulus and intestinal obstruction. E: Patent omphalomesenteric duct. F:

Omphalomesenteric sinus and cyst formation.

The incidence rate of Meckel diverticula in the general population is about 2%, with a 2:1 male-tofemale predominance. The risk of developing symptoms from the diverticulum decreases with age, and

the vast majority of subjects remain asymptomatic. About half of the persons who do become

symptomatic are younger than 2 years. Table 103-7 outlines several of the more common clinical

presentations of symptomatic Meckel diverticulum.

Hemorrhage. Gastrointestinal bleeding related to Meckel diverticulum generally results from peptic

ulceration of the adjacent ileal mucosa. Clinically, it manifests as painless, episodic hemorrhage that is

typically bright red to maroon in color; melena is not characteristically seen. Bleeding from Meckel

diverticulum is generally not hemodynamically significant or exsanguinating, but it can be persistent

enough to require transfusion. The diagnostic test of choice is the 99mTc-pertechnetate radioisotope scan

(Meckel scan) because of the high affinity of the isotope for gastric mucosa and the high probability of

gastric mucosa within a symptomatic Meckel diverticulum. Diagnostic accuracy is reported to be as high

as 90% for Meckel-related bleeding. Contrast studies and endoscopy have a limited role when the

problem is hemorrhage from a Meckel diverticulum.

DIAGNOSIS

Table 103-7 Signs and Symptoms of Meckel Diverticulum

Obstruction. Intestinal obstruction associated with omphalomesenteric duct anomalies usually results

from either intussusception or volvulus around an abnormal attachment between the bowel and the

abdominal wall. In about 5% to 10% of persons with symptomatic Meckel diverticula, intussusception is

the initial symptom. In patients with Meckel diverticula whose initial symptom is small bowel

obstruction, about half have intussusception, and the remainder have volvulus, internal hernias, or other

mechanical causes. Intussusception secondary to a Meckel diverticula has a decreased likelihood for

successful enema reduction. Small bowel obstruction from volvulus around an omphalomesenteric band

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requires operative exploration and treatment.

Diverticulitis. About one-third of patients with symptomatic Meckel diverticulum have acute

diverticulitis. Similar to appendicitis, intraluminal obstruction at the base of a Meckel diverticulum can

lead to distal inflammation, gangrene, and subsequent perforation. Peptic ulceration also can lead to

local inflammation and perforation with the development of peritonitis. The signs and symptoms of

Meckel diverticulitis are virtually indistinguishable from appendicitis, and exploration is both diagnostic

and therapeutic.

Umbilical Anomalies. About 10% of patients with yolk stalk or persistent omphalomesenteric duct

anomalies have umbilical problems. The usual clinical presentation is persistent drainage or intestinal

mucosa found at the umbilicus. The diagnosis can be confirmed by contrast sonogram of the umbilical

orifice or tract. Occasionally, ultrasound examination may be useful to demonstrate omphalomesenteric

cysts. Ultimately, surgical exploration may be required for both diagnosis and treatment.

Meckel Diverticulum as an Incidental Finding. The management of an incidentally discovered

Meckel diverticulum during abdominal exploration for other reasons is controversial. The risk of

resecting an asymptomatic diverticulum must be weighed against the reasons for the operative

exploration, patient age, and the potential for future symptoms from the diverticulum. Infants younger

than 2 years are at greater probability of becoming symptomatic from Meckel diverticula. Resection is

clearly indicated with demonstration of heterotopic gastric mucosa in the diverticulum to prevent peptic

ulceration. This finding may occasionally be determined by direct palpation because the gastric mucosa

is thicker than ileal mucosa. Abnormal omphalomesenteric bands to the abdominal wall should also be

excised. If clinical judgment suggests that the diverticulum is at risk for luminal obstruction, resection is

warranted.

Treatment

Infants and children with symptomatic umbilical abnormalities from yolk stalk remnants are usually

well, and umbilical exploration with possible laparotomy can be undertaken electively. The yolk stalk

remnant is excised, and, if present, the communication with the ileum is closed primarily with minimal

morbidity and mortality. Operative exploration is required for patients with symptomatic Meckel

diverticula. Typically, exploration can be accomplished through a variety of incisions. The treatment of

choice is resection through either antimesenteric wedge excision or segmental bowel resection with

primary closure or anastomosis. Laparoscopic diagnosis and management of Meckel diverticulum has

also been described.144 In the absence of associated medical problems, excellent functional outcome is

expected with minimal morbidity and essentially no mortality unless intestinal necrosis has occurred.

Foreign Bodies

Ingestion of foreign bodies by infants and children is common. Toddlers in the age range of 9 months to

2 years are at particular risk given newly acquired mobility and the tendency for oral exploration. The

type of foreign body and the location in the gastrointestinal tract on discovery dictate overall

management.

Esophagus

Typical foreign bodies found in the esophagus include coins and small toys. In normal children, these

objects become impacted at predictably narrow portions of the esophagus, including the

cricopharyngeus, the esophagus at the level of the left mainstem bronchus, and the gastroesophageal

junction. Previous areas of esophageal repair or injury predispose to points of obstruction. In particular,

infants and children with repaired esophageal atresia, gastroesophageal reflux, or caustic esophageal

injury are at risk for impaction at these sites.

Esophageal foreign bodies produce clinical symptoms of drooling, feeding intolerance (particularly to

solids), dysphagia, and pain. Unrecognized foreign bodies with unusual configuration or sharp points

and edges may cause esophageal perforation and mediastinitis. The diagnosis is straightforward on plain

radiographs if the object is metallic or radiopaque. If a radiolucent object is suspected, an upper

gastrointestinal contrast study is usually required to confirm the diagnosis. Lateral plain films of the

neck or chest may be useful to differentiate between small foreign bodies in the esophagus or the

trachea.

Foreign bodies impacted in the esophagus cause partial esophageal obstruction and can cause

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complications including aspiration, erosion, perforation, and late stricture formation. Therefore, all

esophageal foreign bodies should be removed. Extraction of foreign objects can be accomplished by

using balloon catheter retrieval under fluoroscopic guidance or direct visualization using endoscopy.

Performed within 24 hours of ingestion, balloon catheter retrieval of esophageal foreign bodies is

relatively straightforward. This technique is limited to smooth radiopaque objects such as coins to

minimize the risk of esophageal perforation. The most significant risk with balloon catheter retrieval is

potential aspiration from an unprotected airway, and this must be anticipated as the foreign body

traverses the pharynx. Alternatively, for esophageal coin impaction of less than 24 hours’ duration in

children without a history of esophageal surgery or injury, esophageal bougienage with clearance of the

coin into the stomach has been successful.145

Retrieval of esophageal foreign bodies under direct endoscopic vision requires general anesthesia.

Either flexible or rigid endoscopy systems are widely available and used with individual and

institutional preferences. Esophageal perforation, the major risk, occurs in fewer than 5% of cases in

most reported series. Longstanding esophageal foreign bodies may erode into the aorta and cause lifethreatening hemorrhage from aortoesophageal fistula.146

Distal Gastrointestinal Tract

More than 95% of foreign bodies that pass beyond the gastroesophageal junction proceed uneventfully

through the gastrointestinal tract. The transit time for an asymptomatic foreign body is highly variable

and can take hours to weeks. Progress of an asymptomatic radiopaque foreign body can be followed by

abdominal plain films, but this is rarely useful from a clinical standpoint unless it is a battery. The stool

may also be screened to confirm passage of a known foreign body.

Operative exploration or endoscopic retrieval of distal gastrointestinal foreign bodies is generally

reserved for clinical symptoms related to either obstruction or intestinal injury heralded by abdominal

pain, vomiting, fever, or peritonitis. In addition, persistence of an asymptomatic foreign body in the

stomach for several weeks is a relative indication for upper endoscopic retrieval, particularly with

foreign bodies with irregular shape, configuration, or sharpness. This is a clinical judgment that is best

reserved for an experienced pediatric surgeon because remarkably complex and improbable objects may

pass uneventfully through the gastrointestinal tract. For asymptomatic foreign bodies lodged distal to

the stomach, a relative indication for operative removal is a fixed, persistent location in the intestine

longer than 1 week in duration.

Ingested batteries, in particular alkaline disc batteries, are a potentially serious hazard to children and

require a more aggressive approach. Disruption of the battery casing and spillage of the contents have

been reported to cause intestinal injury and perforation, presumably because of leakage of potassium or

sodium hydroxide. Esophageal impaction of a battery warrants prompt removal when recognized

because the risk of acquired esophageal injury, perforation, and development of traumatic

tracheoesophageal fistula is present.147 In the distal bowel, cathartics may be helpful to expedite

passage of the battery. Operative removal may be necessary if the battery fails to progress distally over

a few days or if symptoms related to the battery occur. Notably, the vast majority of batteries pass

through the gastrointestinal tract uneventfully. Ingestion of multiple magnets can cause problems with

small bowel obstruction or enteroenteric fistula formation.

Gastrointestinal Hemorrhage

The subject of gastrointestinal hemorrhage and general principles of management are discussed

elsewhere this book. The following section reviews some of the important and age-dependent clinical

causes and unique issues of gastrointestinal bleeding in pediatric population. These causes are age

dependent and are summarized in Tables 103-8 and 103-9.

Diagnostic workup of an infant or a child with gastrointestinal hemorrhage requires coordinated

participation among pediatricians, surgeons, gastroenterologists, and radiologists. Several general

principles governing the diagnostic approach to gastrointestinal bleeding in infants and children follow:

a. A clear diagnosis can be made in most situations; given the current technology available to assist with

diagnosis, an aggressive approach is warranted. Diagnostic procedures such as flexible fiberoptic

endoscopy, radioisotope imaging, and angiography are widely available, safe, and applicable to any

age group, including the newborn. Despite these measures, in approximately 16% of cases, the cause

of guaiac-positive stools in a neonate or infant remains unknown,148 and the bleeding is self-limited.

Table 103-8 Etiology and Causes of Upper Gastrointestinal Hemorrhagea

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ETIOLOGY

Table 103-9 Causes of Lower Gastrointestinal Hemorrhagea

b. The primary diagnostic investigation of choice for upper gastrointestinal bleeding is

esophagogastroduodenoscopy. This procedure is optimally performed within the first 24 hours after

cessation of active hemorrhage and usually requires general anesthesia. Imaging studies for active

upper gastrointestinal hemorrhage are limited in their ability to aid with diagnosis.

c. Infants and children presenting with minor lower gastrointestinal bleeding are best evaluated by a

careful perineal and digital rectal examination, followed by anoscopy.

d. Massive lower gastrointestinal hemorrhage in an infant or a child outside the newborn period is most

likely the result of a bleeding Meckel diverticulum.

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e. If a definitive source for lower gastrointestinal hemorrhage is not found on colonoscopy, evaluation

for an upper gastrointestinal source, including upper endoscopy and diagnostic laparoscopy, is

warranted.

f. Pain is an uncommon symptom with pediatric gastrointestinal hemorrhage and implies a more

complex problem such as volvulus, ischemic bowel, or inflammatory bowel disease. Painful

gastrointestinal hemorrhage in pediatric patient requires urgent evaluation and prompt diagnostic

workup.

g. In contrast to that in adults, gastrointestinal bleeding in children is rarely a symptom or sign of

gastrointestinal neoplasm.

Neonates (0 to 30 Days of Age)

The most common cause of gastrointestinal hemorrhage in a neonate is gastritis. Endoscopic evaluation

of newborns with symptomatic upper gastrointestinal hemorrhage demonstrates gastritis or esophagitis

in 50% to 75% of cases. About 10% to 15% have swallowed maternal blood during birth, and 10% of

newborns are found to have an underlying coagulopathy. Anatomic lesions requiring operative control

are distinctly unusual in this age group. Significant and sometimes massive upper gastrointestinal

hemorrhage may occur in a neonate without a definable anatomic lesion despite endoscopic evaluation.

This finding is usually the result of gastritis, and treatment is directed at blood and volume replacement

and correction of any underlying coagulopathy.

Significant conditions responsible for lower gastrointestinal bleeding in the newborn include NEC,

malrotation with volvulus, enterocolitis, or bowel obstruction secondary to an incarcerated inguinal

hernia. These clinical entities present with characteristic histories, findings on clinical examination, and

surgical treatment guidelines previously discussed. Anorectal fissure is also common and easy to

diagnose in neonates, and bleeding is typically self-limited.

Infants (30 Days to 1 Year)

Infants with upper gastrointestinal bleeding deserve comprehensive evaluation, including endoscopy, to

identify potential lesions requiring operative intervention. The most common causes of lower

gastrointestinal hemorrhage in this age group include infectious diarrhea, intussusception, food allergy,

and bleeding Meckel diverticulum. Most of these lesions have distinct symptoms, signs, and diagnostic

findings to facilitate diagnosis. Infectious diarrhea is usually accompanied by fever, feeding intolerance,

possibly emesis, and abdominal pain. Fecal leukocytes may be present on stool examination, and enteric

pathogens or their toxins can be identified by stool culture.

Children (1 to 12 Years)

An important surgical cause of upper gastrointestinal bleeding in this age group includes esophageal

variceal bleeding from portal hypertension. Children with biliary atresia or extrahepatic portal venous

obstruction account for most cases of variceal bleeding in this age group. In the acute setting,

endoscopic sclerotherapy or banding is used as a temporizing measure for hemorrhage control; some

investigators advocate maintenance sclerotherapy. Ultimately, for these children, orthotopic liver

transplantation may offer definitive surgical treatment. The use of operative portosystemic shunts for

acute variceal hemorrhage is not widely used in pediatric surgical practice in the United States.

Conditions causing lower gastrointestinal bleeding in this age group include juvenile polyps. These

are benign, hamartomatous polyps and represent the single most common cause of lower

gastrointestinal bleeding in children. About 20% to 30% of the polyps are palpable on digital rectal

examination. A history of painless, bright red blood per rectum during a bowel movement is typical.

The bleeding results from mucosal irritation, involution, and sloughing of a pedunculated polyp and is

usually not associated with hemodynamically significant hemorrhage. Tissue may be passed or the

pedunculated polyp may prolapse out the anus. A hypochromic, microcytic anemia may be present.

Diagnostic workup generally involves a contrast enema to identify the polyp and evaluate the colon for

synchronous lesions. Colonoscopy may require general anesthesia in this age group, and endoscopic

snare polypectomy is the treatment of choice for appropriate-sized polyps. Infrequently, transanal

excision or open resection of larger polyps is required. In the case of multiple juvenile polyps not

amenable to endoscopic polypectomy, management may be expectant based on the benign natural

history characterized by involution during adolescence. Histologic confirmation is necessary to

differentiate these lesions from adenomatous polyps seen in familial polyposis syndromes or Gardner

syndrome.

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Older Children and Adolescents (Older Than 12 Years)

Causes of both upper and lower gastrointestinal hemorrhage in this age group include most etiologic

conditions found in adults. Importantly, inflammatory bowel disease is significant in this age group.

Intestinal Duplication

The embryologic origin of enteric duplication formation remains controversial, but duplication likely

represents abnormal development of either a diverticulum or adjacent portion of the developing gut. In

some cases, duplication cysts of the upper gastrointestinal tract may be associated with thoracic spinal

cord or vertebral defects; this association appears to reflect abnormal sequestration and integration of

developing primitive notochord elements in addition to duplication. The resulting lesions are described

as either cystic or tubular based on their gross appearance (Fig. 103-43). All types of gastrointestinalderived epithelia are found, but the clinically relevant finding is ectopic gastric mucosa. Duplications

are commonly found along the mesenteric border of the native bowel. The muscular wall is typically

well developed and intimately attached to the functional bowel. In addition, the blood supply is also

shared with the functional intestine, an important surgical consideration.

Cystic Duplications

Cystic duplications may be found throughout the gastrointestinal tract. They are frequently located in

the esophagus and the hindgut, particularly the rectum. Direct communication between a duplication

cyst and the functional gut lumen is unusual. Typically, asymptomatic duplications are discovered as

incidental mass lesions during diagnostic imaging studies, particularly when the location is the thoracic

cavity or the rectum. Duplications also may present as symptomatic lesions from ectopic gastric mucosa

leading to ulceration and bleeding. Other potential presenting symptoms of enteric duplication include

obstruction, intussusception, perforation or traumatic rupture, torsion, infection, and occasional

malignant degeneration. Useful examinations to define the extent of the lesion include ultrasound, CT

scanning, MRI studies, and contrast studies. The identification of enteric duplication on routine prenatal

ultrasound examination has been reported.

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Figure 103-43. Enteric duplication. A: Cystic duplication of the terminal ileum. B: Tubular duplication of the terminal ileum and

the colon.

The treatment of all cystic duplications is operative. Even in asymptomatic infants and children,

uncertainty regarding the nature of the mass and the potential for subsequent problems dictates surgical

exploration. Esophageal and rectal duplication cysts are generally amenable to simple excision. In

contrast, duplication cysts of the small intestine usually require segmental resection and primary

anastomosis, given the intimate attachment and shared blood supply with the native bowel. For large

cystic duplications involving longer segments of native bowel, individualized treatment strategies are

required. One option is cyst marsupialization with resection of the duplication cyst wall with

preservation of the common blood supply and wall between the cyst and the native bowel. This

technique is combined with submucosal dissection and stripping of the remaining epithelium from the

cyst wall. Another approach is internal drainage of the cyst into the adjacent native intestine, for

example, creation of a cystoduodenostomy for duodenal duplication not amenable to local resection and

anastomosis; this would be distinctly unusual.

Tubular Duplications

Tubular duplications may be found anywhere along the length of the gastrointestinal tract. They are less

frequent than cystic duplications and have a tendency to involve the ileum and the colon. It is believed

that tubular duplication generally reflects abnormal, disordered recanalization of the gastrointestinal

tract. Similar to cystic duplications, tubular lesions share a common wall and blood supply with the

native bowel. Communication between the tubular duplication and native bowel lumen is common.

Tubular duplications may be extensive and can involve the entire length of terminal ileum and colon.

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Malformations of the entire colon and rectum are associated with genitourinary anomalies, particularly

duplications of the external genitalia or bladder.

Tubular duplications manifest clinically in similar fashion to cystic lesions. Symptomatic lesions most

commonly present with gastrointestinal bleeding or obstruction. Treatment is operative, and an

individualized strategy is required that is based on the location and nature of the duplication. Resection

with primary anastomosis may require removal of an unacceptable length of normal bowel.

Marsupialization with submucosal stripping of the duplication epithelium may be particularly helpful if

ectopic gastric mucosa is suspected or found. Obstruction from a long, blind-ending parallel duplication

that communicates with the functional gut lumen can be treated effectively with a reentry procedure

such as a distal enteroenterostomy. This approach avoids a potentially complex resection of a significant

length of bowel.

The outcomes of surgical management of enteric duplications are generally excellent in the absence of

other associated anomalies or medical problems. Mortality attributable to the duplication itself is

unusual. Postoperative morbidity is generally dependent on the nature and location of the duplication.

Mesenteric and Omental Cysts

Mesenteric and omental cysts are rare lesions thought to result from the sequestration of lymphatic

tissue during development. Mesenteric cysts are twice as common as omental cysts. Both are

characterized by thin, often incomplete walls lined with endothelial cells absent of surrounding smooth

muscle. They may be filled with either serous lymphatic fluid or chyle and may be unilocular or

multilocular. These cysts may become extraordinarily large before producing symptoms.

Most infants and children with mesenteric or omental cysts are diagnosed prior to adolescence.

Asymptomatic children are usually diagnosed incidentally during studies for other reasons. Symptomatic

children present with abdominal pain, and, on examination, a soft, mobile abdominal mass is

characteristic. Bleeding, rupture, obstruction, torsion, or cyst infection may be observed. Most of these

lesions can be diagnosed by ultrasound or CT scan imaging. Ascites, duplication cysts, pancreatic

pseudocysts, and large ovarian cysts may have a similar appearance on diagnostic imaging. Peripheral

calcification and evidence of recent hemorrhage may be seen in mesenteric or omental cysts (Fig. 103-

44).

The treatment for these lesions is simple excision. Total excision of mesenteric or omental cysts is

generally preferable over partial excision with marsupialization. Limited resection with primary

anastomosis may be required for a mesenteric cyst located adjacent to the intestinal wall, particularly if

there is concern that the cyst actually may be an enteric duplication. Morbidity and mortality are

generally limited to concurrent problems associated with the intestine. In particular, volvulus of a

mesenteric cyst may cause vascular compromise and infarction of the adjacent intestine.

Figure 103-44. Computed tomographic scan of a child after abdominal trauma. Hemorrhage into large omental cyst is apparent

(arrows).

Primary Peritonitis

Bacterial peritonitis without a specific, identifiable cause is referred to as primary peritonitis.

Spontaneous bacterial peritonitis in children with ascites or nephrosis is generally included in this

group. Hematogenous seeding of ascitic fluid is probably responsible for the development of

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spontaneous bacterial peritonitis. The infecting bacterial organisms were classically gram-positive with

a variety of staphylococcal, streptococcal, and other species accounting for most cases. In a series of

infants and children with primary peritonitis, more than two-thirds of the cases were caused by gramnegative organisms such as Escherichia coli.149 This trend may reflect the use of antibiotic prophylaxis

directed against gram-positive organisms.

The other etiologic mechanism for the development of primary peritonitis is believed to involve

retrograde inoculation of the peritoneal cavity via the genitourinary tract. This etiology is characteristic

of prepubertal girls 5 to 10 years of age, accounting for as many as half of the cases of primary

peritonitis. The initial signs and symptoms in these children are virtually identical to those in children

with perforated appendicitis: fever, emesis, abdominal pain, and tenderness on examination.

Leukocytosis is characteristic, and an ileus is observed on plain abdominal films. On exploration, these

children have inflammatory peritonitis without an identifiable enteric cause. Gram-negative enteric

organisms are commonly cultured from the peritoneal fluid.

Infants and children with peritonitis in association with an indwelling peritoneal dialysis catheter or

ventriculoperitoneal shunt may be treated successfully with intravenous broad-spectrum antibiotics. The

catheter or shunt should be removed or exteriorized promptly if peritonitis does not resolve within 24

to 48 hours.150 In association with ascites or nephrosis, diagnostic paracentesis should be performed and

the peritoneal fluid examined by Gram stain and culture. If there is any diagnostic uncertainty,

laparoscopic or open operative exploration may be required to exclude intestinal perforation as a cause

of peritonitis. If the appendix is normal, peritoneal cultures should be obtained and a thorough,

complete abdominal exploration for other causes should be performed. Appendectomy is generally

performed when the diagnosis of primary peritonitis is established by a right lower-quadrant incision.

Other than perforated appendicitis, distinct causes of intestinal perforation or peritonitis in this age

group include perforated Meckel diverticulum, duodenal ulcer, and acute pancreatitis. About half of the

peritoneal fluid cultures are positive for a single organism. Treatment with specific antibiotics is

continued until the patient is afebrile with a normal white blood cell count and normal clinical

examination. Following operative exploration in primary peritonitis, the morbidity is no different than

that for appendectomy, and the recovery is generally uneventful.

ETIOLOGY

Table 103-10 Common Causes of Neonatal Ascites

Ascites

The common causes of neonatal and childhood ascites are listed in Tables 103-10 and 103-11. The

clinical presentation is that of abdominal distention with bulging flanks and demonstrable fluid on

palpation and percussion. Ultrasound or CT scan imaging may be useful to confirm the clinical

diagnosis. Paracentesis and routine examination of the fluid for Gram stain, cell count, cytology,

protein, chemistries, and culture should be performed. Chylous ascites is characterized by a white milky

appearance, high lymphocyte count, and high triglyceride content. Bile-stained fluid in the absence of

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