Necrotizing enterocolitis is a neonatal disease thought to be caused by an immune overreaction to an insult to the intestine followed by inflammation, bacterial translocation, and coagulation necrosis of the intestine. Overall mortality is 15% to 30%, with many survivors left with short bowel syndrome and growth retardation.4 While necrotizing enterocolitis is largely a disease of prematurity, 10% of cases occur in term infants.5 Predisposing conditions include congenital heart disease, sepsis, neonatal asphyxia, polycythemia, and hypotension.6 The range of mean ages at onset of disease is between 2 and 9 days of age. Therefore, although the disease rarely presents outside of the neonatal intensive care unit, its severity makes it an important consideration in near-term infants or those with comorbidities in the first 3 weeks of life.
Clinical Features and Imaging
Presenting signs and symptoms are poor feeding, lethargy, abdominal distension, bilious vomiting, temperature instability, apnea, and abdominal tenderness. Gross or occult blood in the stool increases the likelihood of necrotizing enterocolitis but is neither sensitive nor specific.7
Obtain antero-posterior and lateral decubitus abdominal radiographs. Inclusion of the chest will screen for cardiopulmonary abnormalities. Early in the disease, abdominal radiographs may show signs of ileus or obstruction. Pneumatosis intestinalis (air in the bowel wall) and portal venous gas are both pathognomonic (Figure 130-1),8 but normal abdominal radiographs do not exclude the disorder.
Plain abdominal film demonstrating air in the intestinal wall (arrows), which is pathognomonic of necrotizing enterocolitis. [Reproduced with permission from Strange GR, Ahrens WR, Schafermeyer RW, Wiebe RA: Pediatric Emergency Medicine, 3rd ed. © 2009. The McGraw-Hill Companies, Inc. New York, Figure 9-12.]
Evaluation must include a search for underlying causes, especially sepsis. Management includes nothing by mouth status, gastric tube decompression, aggressive IV hydration, broad-spectrum antibiotics, and surgical consultation. Consider ampicillin to cover gram-positive organisms, gentamicin or cefotaxime for gram-negative organisms, and metronidazole or clindamycin for anaerobes.9 Although necrotizing enterocolitis is first managed medically, many cases require resection of necrotic bowel. Admit to intensive care.
Volvulus is a life-threatening complication of malrotation. Eighty percent of malrotation presents within the first month of life and 90% within the first year, but it can present at any time in life.10 At approximately 10 weeks of gestation, the growing intestines return to the abdomen from the yolk sac, and the midgut undergoes a 270-degree counterclockwise turn around the superior mesenteric artery. Abnormal rotation can leave the cecum high in the abdomen, with its peritoneal attachments (Ladd's bands) crossing the duodenum. Down's syndrome, heterotaxy, and duodenal atresia are associated with malrotation.
The child may be well until the malrotated gut twists (volvulus) or becomes obstructed by Ladd's bands, causing ischemia.
Volvulus is a surgical emergency as it can result in gangrene of the entire midgut within hours. The infant with volvulus often has no significant past medical history and presents with the abrupt onset of constant abdominal pain, bilious vomiting, abdominal distention, and irritability. Patients with volvulus are typically ill appearing and may have signs of shock. The abdomen is diffusely tender and distended and may be rigid. Intermittent volvulus may present with stable vital signs and focal tenderness on abdominal examination. The absence of fever can be helpful in distinguishing volvulus from sepsis.
Imaging studies should not delay surgical consultation, as rapid detorsion of the volvulized bowel is necessary to prevent loss of the entire small intestine. Upper GI series with contrast remains the test of choice for diagnosing malrotation with sensitivities of 93% to 100% for malrotation and 54% to 79% for volvulus.11 The normal location of the duodenojejunal junction is at the level of the duodenal bulb and to the left of the spine. In malrotation, the junction is commonly located low and to the right of the spine. If midgut volvulus is present at the time of the study, there may be an abruptly tapered cutoff of contrast in the duodenum (bird's beak) or a corkscrew appearance of the bowel. If concern persists after a negative study and surgical consultation, options for additional evaluation include repeat upper GI series to exclude intermittent volvulus, abdominal CT, US, and contrast enema.
Plain abdominal radiographs are neither sensitive nor specific for malrotation. The most common findings on plain abdominal x-ray are an air-filled stomach with little distal gas, which may show a distal obstruction, nonspecific, or even normal gas pattern.12
Treatment consists of resuscitation and immediate surgical consultation. Electrolytes, CBC, coagulation studies, and a type and cross-match for packed red blood cells are helpful to guide resuscitation and operative management.
Intussusception is the most common cause of intestinal obstruction in children under 2 years of age. It is rare before 2 months. The male:female ratio is 2:1.13,14
Intussusception occurs when one segment of the intestine telescopes into another, usually the ileum into the colon. Constriction of the mesentery results in engorgement of the intussusceptum and bowel ischemia. In infants, lymphoid hyperplasia from viral illness may cause a "lead point," which drags one portion of bowel into another. In older children, causes of intussusception include Meckel's diverticulum, intestinal polyps, congenital duplications, lymphoma, and Henoch–Schönlein purpura, and possibly exposure to antibiotics.15
Intussusception is notoriously difficult to diagnose because its two common presentations, intermittent pain and lethargy, are insensitive signs of intussusception. The classic presentation of the "intermittentsception" is an infant aged 5 to 12 months who suddenly develops a few minutes of severe abdominal pain with the legs drawn to the chest and who then appears well until the next episode of pain. An alternate presentation is an infant with unexplained lethargy, which may divert the provider to an evaluation for altered mental status. Vomiting is not usually present at first but develops over 6 to 12 hours and may be bilious.
The physical examination between attacks may be normal, although a sausage-shaped mass may be palpated in the right upper quadrant. Occult blood is found in 70% of stools and gross blood in about 50%, although it rarely resembles the classic "currant" jelly.16,17
A history consistent with the intermittent symptoms of intussusception should prompt further evaluation or observation even if the patient is asymptomatic at the time.
US should be the first study when the diagnosis is ambiguous. In research settings, the accuracy of US for intussusception is nearly 100% (Figure 130-2).
A and B. US image of intussusception showing the classic target appearance of bowel-within-bowel. [Reproduced with permission from Ma OJ, Mateer JR, Blaivas M: Emergency Ultrasound, 2nd ed. © 2008, McGraw-Hill, New York, Figure 9-15.]
Children with a high suspicion of intussusception should undergo immediate air-contrast enema, which is both diagnostic and therapeutic.17 Prepare the child for reduction with boluses of normal saline, as volume loss due to intestinal edema, decreased intake, and vomiting is a common comorbidity. A surgeon should be notified prior to air-contrast enema in case the reduction is unsuccessful or perforation occurs. Children with peritonitis, with free air on plain radiographs, or who are in shock should not undergo air-contrast enema and require emergent surgical reduction.
Plain abdominal radiographs are not highly useful unless needed to rule out perforation, but they may show a mass or paucity of bowel gas in the right abdomen, a "crescent sign" where the curved edge of one segment of bowel visibly protrudes into another, or an obstructive pattern (Figure 130-3).16
The crescent-shaped head of the intussusceptum is seen as an intraluminal mass in the gas-filled transverse colon (asterisk). [Reproduced with permission from Schwartz: Emergency Radiology Cases Studies © 2008, The McGraw-Hill Companies, Inc. New York. Figure II-4-6 Part A.]
Children have traditionally been admitted after enema reduction because of a 10% recurrence rate, usually within the first 24 to 48 hours.17 However, discharge after a few hours of observation to exclude complications may be appropriate in children with a normal WBC count, who can tolerate oral intake, and who can easily return should they have a recurrence.18 A recurrence should prompt a second enema reduction. Further recurrences may require surgery.
Appendicitis is the most common surgical emergency in children. The peak ages for appendicitis are between 9 and 12 years, with a male predominance.19
The appendix is a diverticulum that arises from the cecum. Appendicitis usually begins with obstruction of the appendiceal lumen by fecaliths, lymphoid hyperplasia, or less commonly parasites, tumors, or foreign bodies. Multiplying bacteria and mucus secretion increase pressure on the wall, leading to dilation, ischemia, and perforation.
The classic progression of periumbilical pain that migrates to the right lower quadrant followed by vomiting and fever is seen in less than 50% of children with appendicitis.20 Many of the classic symptoms are seen with only moderate frequency: pain of <48 hours in duration (82%), nausea or emesis (71%), anorexia (60%), and migration of pain to the right lower quadrant (50%). Constipation is seen in 9% to 33% of cases and diarrhea in 10% to 33%.21 Perforation rates approach 90% in children <4 years old, so younger children are more likely to present with vomiting, fever, peritonitis, or sepsis.22
Children with appendicitis may perforate early in the course of the disease. One study of children aged 3 to 18 found no perforation before 12 hours, but a 10% perforation rate at 18 hours and 44% by 36 hours.23 Perforation may cause a brief remission in pain prior to the development of peritonitis and worsening symptoms.
Tenderness may be localized to the right lower quadrant (68% of cases) or McBurney's point (two thirds of the way from the umbilicus to the anterior-superior iliac spine), or may involve the entire abdomen. Assessing pain when the child coughs, walks, and jumps is a useful tool to assess for peritoneal inflammation. Rebound tenderness and guarding are more common with perforation and may be absent early. Assess for hernias and perform a testicular examination in boys. A pelvic examination may be needed in adolescent females to compare the tenderness of McBurney's point to the adnexa. Rectal tenderness had a positive likelihood ratio of 2.3 and negative ratio of 0.7 in a summary of three studies.22
There is a high potential for missing the diagnosis of appendicitis in children. The Alvarado and Samuel scores have been widely cited but have insufficient positive predictive values to safely identify the need for surgery for appendicitis in children, and other decision rules may or may not be generalizable24,25,26 (Table 130-2). Problems with interrater reliability make it difficult to apply decision rules in the clinical prediction of appendicitis15 (Table 130-3).
TABLE 130-2A Clinical Decision Rule to Identify Children at Low Risk of Appendicitis* (rule has poor positive predictive value) |Favorite Table|Download (.pdf) TABLE 130-2 A Clinical Decision Rule to Identify Children at Low Risk of Appendicitis* (rule has poor positive predictive value)
|Criterion ||Points |
|Absolute neutrophil count >6.75 × 103/μL ||6 |
|Rebound pain or pain with percussion ||2 |
|Unable to walk or walks with limp ||1 |
|Nausea ||2 |
|History of migration of pain to right lower quadrant ||1 |
|History of focal right lower quadrant pain ||2 |
TABLE 130-3Interrater Reliability of Selected Historical and Clinical Variables Used in the Clinical Assessment of Appendicitis |Favorite Table|Download (.pdf) TABLE 130-3 Interrater Reliability of Selected Historical and Clinical Variables Used in the Clinical Assessment of Appendicitis
|Sign or Symptom ||Agreement, % ||Kappa (95% CI) |
|Focal RLQ pain ||84.9 ||0.48 (0.39–0.58) |
|Migration of pain to RLQ ||68.4 ||0.37 (0.29–0.45) |
|Nausea ||72 ||0.44 (0.37–0.52) |
|Rebound ||68.4 ||0.32 (0.24–0.40) |
|Abdominal pain with walking, jumping, or coughing ||83.6 ||0.54 (0.45–0.63) |
WBC count has insufficient sensitivity or specificity to confirm the diagnosis of appendicitis; however, a normal WBC is strongly correlated with a decreased likelihood of appendicitis.24 A WBC <10,000/mm3 is a strong negative predictor for appendicitis (negative likelihood ratio = 0.26). C-reactive protein is a nonspecific later marker of inflammation and correlates with severity of appendicitis and may be helpful for distinguishing ruptured or gangrenous appendicitis from early disease. No single cut-point for C-reactive protein has been established, however, as a sensitive or specific marker of acute surgical appendicitis; some studies suggest that C-reactive protein in conjunction with WBC and clinical signs and symptoms may add to the diagnostic evaluation of children with abdominal pain.27,28,29,30,31,32,33 Sterile pyuria can be seen with acute appendicitis as the inflamed appendix irritates the nearby ureters.
Patients with a history and examination compelling for acute appendicitis should have surgical consultation without diagnostic imaging. When the diagnosis is uncertain, US is often the preferred initial imaging exam. Appendiceal findings include a maximal diameter >6 mm, wall thickness ≥3 mm, lack of compressibility, hyperemia on color Doppler US, surrounding edema or fat stranding, and an appendicolith (Figure 130-4).25 If done by experienced technicians, US is highly sensitive and specific (88% and 94%).26 However, studies of the performance of US outside of controlled research settings have been less optimistic, and one study reported visualizing the appendix in only 24% of children.34 US is useful to exclude gynecologic processes such as ovarian torsion and ruptured cysts. A US with findings of appendicitis in a patient with a consistent clinical picture is sufficiently specific to warrant surgery. When the appendix is visualized and normal, US is sufficiently sensitive to exclude appendicitis in many cases. If clinical suspicion for appendicitis is very high, visualization of a normal appendix should not exclude the diagnosis, and additional evaluation should be undertaken. This may include surgical consultation, CT scan, admission for observation, or repeat US.
US of acute appendicitis with a diameter of 8 mm in short-axis view. [Reproduced with permission from Ma OJ, Mateer JR, Blaivas M: Emergency Ultrasound, 2nd ed. © 2008, McGraw-Hill, New York, Figure 18-23.]
Abdominal CT scanning has superior test characteristics to US, with a sensitivity and specificity of 94% and 95%, respectively (Figure 130-5). Abdominal CT is useful for identifying perforation and abscess formation, which may require percutaneous drainage and antibiotics rather than immediate appendectomy, and therefore may be the preferred imaging modality in children with prolonged pain or diffuse peritoneal signs suggestive of rupture. CT may also identify alternative diagnoses such as mesenteric adenitis, epiploic appendagitis, inflammatory bowel disease, renal stones, and tumors. Disadvantages of CT are the radiation exposure, the time required for oral and/or rectal contrast when requested, and the possibility of allergic reactions and IV contrast nephropathy. One study suggests that a single CT scan may triple the risk of malignancy, although the absolute risk remains small and the authors caution that radiation doses from CT scans be kept as low as possible.35 Institutional protocols often determine whether IV contrast CT or both oral and IV contrast CT is the preferred CT modality.
Acute appendicitis. A. A non–contrast-enhanced axial CT scan through the pelvis reveals a calcific appendicolith (arrow) in a pelvic appendix. Inspissated, sometimes calcified fecal material leads to obstruction followed by secondary bacterial invasion. Radiographic evidence of a fecalith is seen in 20% of cases. The presence of an appendicolith along with inflammation is indicative either of acute appendicitis or of impending appendicitis. B. Contrast-enhanced CT scan of the pelvis reveals the previously described appendicolith (arrow) in a dilated fluid-filled and thick-walled appendix. Enhancement of the appendiceal wall is also noted. [Reproduced with permission from Shah BR, Lucchesi M: Atlas of Pediatric Emergency Medicine. © 2006, McGraw-Hill, New York, Figure 10-8.]
Once the diagnosis of appendicitis is highly suspected or confirmed, obtain surgical consultation and admit to the hospital for appendectomy. Antibiotics for nonperforated appendicitis include cefoxitin or ampicillin/sulbactam; for perforated appendicitis, monotherapy with piperacillin/tazobactam is as effective as multidrug therapy.36 Percutaneous drainage may be done if an abscess is present, followed by delayed appendectomy to prevent recurrence. In ambiguous cases, admission for serial abdominal examination by a surgeon is reasonable.
Henoch-Schönlein purpura is a vasculitis of children between 2 and 11 years of age with slight peaks in the fall and winter months. The cause is unknown, although a viral pathogen or group A Streptococcus may trigger the condition. Immunoglobulin A deposits are seen in the glomeruli and vessel walls.
The typical clinical presentation of Henoch-Schönlein purpura is a triad of palpable purpuric rash, acute abdominal pain, and arthritis. The rash occurs in all cases and is the presenting sign in 50% of cases (see chapter 141, Rashes in Infants and Children). The rash may initially be urticarial or macular-papular. The lesions typically appear first on the extensor surfaces of the lower extremities and buttocks; they may involve the arms and ears. The face, palms, and soles are usually spared.
GI symptoms including abdominal pain and GI bleeding occur in 50% to 75% of cases.37 The pain is usually diffuse and colicky in nature and may be associated with vomiting. Abdominal pain usually presents after the rash, but can precede the rash in 30% to 43% of patients. Intussusception occurs in 3.5%.38 Arthralgia or arthritis occurs in 80% of cases and is the presenting sign in 25%. Joint symptoms are migratory and usually involve the knees and ankles with periarticular swelling and tenderness.
Renal involvement including hematuria, edema, and proteinuria is the most significant long-term consequence (see chapter 134, Renal Emergencies in Children). Obtain a urinalysis on all patients to detect hematuria. When hematuria is present, obtain renal function tests. Although microscopic hematuria is relatively common in patients with Henoch-Schönlein purpura, proteinuria and gross hematuria represent more extensive renal involvement. Perform a rectal examination to assess for gross and occult blood. Stool guaiac may be positive in nearly half of cases and, in the absence of intussusception symptoms, does not require further evaluation. Additional laboratory studies, including CBC and coagulation studies, are not routinely indicated in the patient with a characteristic presentation of Henoch-Schönlein purpura, because these studies are normal in this condition. If the patient has a history consistent with accompanying intussusception, obtain an abdominal US or air-contrast enema to assess for this.
Treatment is mainly supportive. If the child is ill appearing, unable to tolerate oral fluids, or dehydrated, begin IV fluid hydration and arrange for admission. Nonsteroidal anti-inflammatory drugs, such as ibuprofen and ketorolac, are used for management of arthritis, painful edema, and abdominal pain if renal function is normal based on urinalysis. Oral corticosteroids reduce symptoms of severe abdominal and joint pain. Care of patients with gross hematuria, more than small proteinuria, abnormal renal function, hypertension, or nephritic syndrome should be discussed with a pediatric nephrologist. Patients without these findings do not need steroids for prophylaxis of renal disease.39 Arrange for repeat urinalysis and blood pressure measurements within 7 days, continuing for 6 months.40
Inguinal hernias occur in up to 45% of children and are more common in those born prematurely.41 Incarceration refers to a hernia that cannot easily be reduced and is the presenting sign of the hernia in up to 65% of cases.42 Incarceration is most common in the first year of life.
A simple inguinal hernia is often asymptomatic and is noted as a scrotal or inguinal mass. Symptoms of incarcerated hernia may include irritability, poor feeding, and vomiting. The differential diagnosis includes torsion of the testicle or testicular appendage, hydrocele of the cord or the scrotum, undescended testicle, inguinal lymphadenopathy, inguinal node abscess, orchitis, and trauma. The incarcerated sac may contain omentum, bowel, or ovary. Because it can be difficult to differentiate an incarcerated hernia from testicular torsion if significant swelling is present, it may be necessary to proceed with consultation and evaluation for both of these time-dependent emergencies simultaneously.
An incarcerated hernia may progress to strangulation and is therefore a surgical emergency. Attempt reduction as soon as possible. Place the patient in the Trendelenburg position. Apply pressure to the hernia sac with one hand while the other guides the contents through the inguinal ring. Reduction may take minutes of steady pressure. Sedation and analgesia can be quite helpful. One third of children redevelop incarceration, so patients should either be admitted for repair or expedited outpatient care should be arranged within 24 hours. If manual reduction is unsuccessful, request immediate surgical consultation. Unlike adults, even inguinal hernias in children that have not become incarcerated require referral for early repair because of the high risk of incarceration.
INFLAMMATORY BOWEL DISEASE
Children account for 20% to 25% of new diagnoses of inflammatory bowel disease.43 In one series, 95% of those <10 years old with Crohn's disease initially presented with abdominal pain, 77% with diarrhea, and 60% with bloody stools.44 The pain in Crohn's disease is often colicky and either diffuse or in the right lower quadrant, mimicking appendicitis. Weight loss is seen in 80% of patients with Crohn's disease. Growth failure may be the only symptom in 5%. Up to 25% of children with inflammatory bowel disease have a positive family history.
Tachycardia and hypotension may be present secondary to dehydration or anemia from chronic blood loss. Inspect the anal area for fistulas, fissures, and skin tags suggestive of Crohn's disease. Extraintestinal signs, including arthritis, ankylosing spondylitis, and erythema nodosum, occur in 20%.
Most children with moderate to severe disease will have anemia and an elevated erythrocyte sedimentation rate. Measure electrolytes in cases of severe diarrhea. If a new diagnosis is being considered, obtain stool culture, ova and parasite examination, and Clostridium difficile toxin to assess for infectious causes. An abdominal CT is commonly obtained to evaluate for thickening of the terminal ileum and complications of Crohn's disease such as intra-abdominal abscesses and fistula. Definitive diagnosis requires endoscopy and biopsy, and a pediatric GI specialist should be consulted for further management, which may include oral or IV corticosteroids. Toxic megacolon is a complication of severe ulcerative colitis in which large bowel dilation is present on abdominal radiograph or CT in the setting of fever, abdominal pain, and laboratory markers of systemic inflammation.45 Treatment requires hospital admission for steroids.46
Calcium-containing renal stones are the most common type in children. Predisposing factors include immobilization, hyperparathyroidism, corticosteroids, diuretics, and neoplasms. Both ketogenic diets and antiepileptic drugs used to treat seizure disorders can predispose to stone formation.
Clinical Features and Diagnosis
Children with renal stones present with abdominal pain only 50% of the time. Microscopic or gross hematuria is present in 85% of children with urolithiasis.47,48 The ED workup should include imaging to exclude severe obstruction (CT or US) and urinalysis to exclude infection, as both of these potentially require immediate intervention. If the patient has never had imaging to confirm the presence of two normal kidneys and labs to confirm baseline normal renal function, these should be obtained. If these studies are abnormal, contact a pediatric nephrologist or urologist.
The imaging evaluation of urolithiasis in children may begin with either US or CT. See chapter 94, Urologic Stone Disease, for a discussion of imaging in adults. In children, US has good specificity but limited sensitivity for urolithiasis (90% for stones within the kidneys, but only 38% for ureteral stones, which are more likely to cause pain). Therefore, US is a sufficient first study if positive, but should be followed by noncontrast CT if negative and urolithiasis is highly suspected. A negative US alone is sufficient if the goal of testing is not to confirm urolithiasis but to rule out obstruction. Plain radiographs have poor sensitivity for stones.
Because of the high rate of underlying metabolic abnormalities in children with urolithiasis (38% to 90%), all children with a new diagnosis require a metabolic evaluation, although this need not be done in the ED.49 Workup may include a basic metabolic panel, serum calcium, phosphorus, parathyroid hormone, and a 24-hour urine collection.50 Anatomic abnormalities including vesicoureteral reflux, ureteropelvic and ureterovesicular junction obstruction, and neurogenic bladder were found in 11% of children with urolithiasis, so plans should be made for subsequent imaging.51 Parents should be instructed to strain the urine so the stone can be analyzed.
ED management is centered on pain and nausea control. If IV placement is indicated for dehydration, pain control, or blood draws, provide aggressive rehydration. Indications for admission include urinary tract infection with obstruction, abnormal renal anatomy or function, uncontrolled pain or nausea, and dehydration. Most stones in the distal ureters smaller than 3 mm will pass spontaneously, while those larger than 4 mm will likely require intervention.52 Discuss patients with larger stones or mild to moderate obstruction with a urologist to plan follow-up. One study of doxazosin 0.03 milligram/kg up to 2 milligrams daily failed to show a benefit for stone passage in children.53 Interventional therapy includes extracorporeal shock wave lithotripsy and urethral or transcutaneous endoscopy to extract the stone.
Dehydration contributes to stone formation; so encourage oral fluids for all children discharged. Those with known metabolic causes for their stones may benefit from dietary modification, diuretics, or other medications specific to their condition.
Pancreatitis is extremely rare in infants and is most commonly a secondary process in children and adolescents. See chapter 79, Pancreatitis and Cholecystitis, for a discussion of its pathophysiology. Table 130-4 lists causes of acute pancreatitis in children.54
TABLE 130-4Causes of acute pancreatitis in children |Favorite Table|Download (.pdf) TABLE 130-4 Causes of acute pancreatitis in children
|Biliary: gallstones and sludge, pancreas divisum ||10%–30% |
|Medications: valproic acid, L-asparaginase, 6-mercaptopurine ||<25% |
|Idiopathic ||13%–34% |
|Multisystem disease: sepsis, shock, systemic lupus erythematosus ||33% |
|Trauma ||10%–40% |
|Infectious: mumps, hepatitis, other viral infection, Mycoplasma ||<10% |
|Metabolic: diabetic ketoacidosis, hypertriglyceridemia, hypercalcemia ||2%–7% |
|Hereditary: cystic fibrosis ||5%–8% |
The typical history is an acute onset of epigastric or periumbilical abdominal pain associated with anorexia, nausea, and vomiting. Although 62% to 89% of children with pancreatitis complain of epigastric pain, <10% describe back pain or radiation of the pain to the back; nausea and vomiting are present in 40% to 80% of older children, but only 28% of children <2 years of age.55 Older children may be able to describe dull, constant epigastric pain that is made worse by eating or lying supine. Physical examination reveals guarding or distension in fewer than half of children with pancreatitis, and Grey Turner sign is present in 2%.55,56 The child may be lying quietly on his or her side with knees flexed.
Acute pancreatitis is defined by an elevation of either lipase or amylase of three times the upper limit of normal, or imaging consistent with pancreatitis. Lipase is between 73% and 100% sensitive in children.57 Lipase rises within hours and remains elevated for up to 14 days. Also testing for amylase will identify some cases of pancreatitis with normal lipase values.55 The level of enzyme elevation does not correlate with the severity of the disease. Obtain electrolytes, including calcium, and liver enzymes, which may suggest hepatic disease or biliary obstruction.
Obtain a US or CT scan to assess for biliary causes (gallstones or sludge) or anatomic abnormalities of the pancreas. US has greater sensitivity for gallstones and gives no ionizing radiation. CT is better at identifying complications of severe pancreatitis including necrosis, fluid collections, and hemorrhage, although these complications are more likely to present a few days into the disease. CT should be ordered if trauma is suspected.
Because intra-abdominal third spacing, shock, and multiorgan system failure are potential complications of acute pancreatitis, aggressively administer normal saline or lactated Ringer's solution. Treat pain and admit the patient to the hospital.
Acute cholecystitis is very rare in children as compared to adults, with only 0.1% to 0.2% of gallstone disease being diagnosed in patients under age 15.58 Bile stones from hemolytic disease, such as sickle cell disease, and total parenteral nutrition are the most common type in children, comprising 9% to 50% in case series. Acute or chronic illness with dehydration, fasting, or mechanical ventilation can cause gallbladder sludge and obstruction in the absence of stones (acalculous cholecystitis). When complicated by bacterial infection of the common bile duct, cholangitis results and is associated with a high risk of sepsis and shock. Children who have undergone surgical Roux-en-Y procedures (e.g., Kasai procedure for biliary atresia) are at risk for ascending cholangitis.
Clinical Features and Diagnosis
Children with biliary pain are typically restless and unable to lie still. Jaundice is more common in children than adults and may occur in the absence of common bile duct obstruction. Right upper quadrant tenderness and a positive Murphy sign may be elicited in older children and adolescents.
Obtain liver function tests and lipase, which may be normal even in cases of acute cholecystitis. US is the first-line test for evaluation of biliary disease. CT scan may demonstrate acute cholecystitis but misses 20% of gallstones.
A child with biliary colic (cholelithiasis without acute cholecystitis, whose pain has resolved) may be discharged with outpatient follow-up. Children with cholecystitis or cholangitis should be admitted. Administer antibiotics for findings of gallbladder infection including fever and elevated WBC count: One common regimen is ampicillin, gentamicin, and clindamycin.59 Cholangitis, with Charcot's triad of right upper quadrant pain, fever, and jaundice, is a medical emergency and requires immediate intervention.
Although a child with pneumonia will often present with respiratory signs and symptoms and fever, the predominant complaint may be abdominal pain. The diagnosis and management of pneumonia in children is discussed in chapter 125, Pneumonia in Infants and Children.
Streptococcus pharyngitis can cause abdominal pain with or without vomiting and without sore throat. Examine the oropharynx of any child ≥3 years of age with abdominal pain. If signs of pharyngitis are present, test for group A Streptococcus. If the rapid strep test is negative, send a throat culture because of the rapid antigen test's good specificity but poor sensitivity.60 See chapter 121, Mouth and Throat Disorders in Infants and Children.
Colic is excessive, unexplained paroxysms of crying in a healthy infant from 2 weeks to 4 months of age, peaking at 6 weeks. Wessel's "rule of threes" is a mnemonic for colic: crying >3 hours per day for >3 days per week for >3 weeks. Sufferers will flex their legs, turn red, and pass large amounts of gas. Colic is a diagnosis of exclusion made by the chronicity of episodes and exclusion of dangerous alternative diagnoses. See chapter 114, Neonatal Emergencies and Common Neonatal Problems.
Constipation is defined as stools that are hard, infrequent, or painful to pass. Constipation may cause significant abdominal pain, prompting extensive evaluation. Normal infants may occasionally go up to 7 days without a bowel movement. As long as the child is not symptomatic and the stool is not hard, no evaluation is necessary.
Hirschsprung's disease is a pathologic cause of constipation in infants. Hirschsprung's disease is caused by a failure of colonic ganglion cells to migrate during gestation and is more common in trisomy 21. A history of failing to pass meconium in the first 24 to 48 hours of life is suggestive of Hirschsprung's disease or cystic fibrosis. Symptoms include infrequent, explosive bowel movements, poor growth and feeding, and progressive abdominal distension.
Constipation may be seen in older children with chronic medical conditions such as anorexia nervosa, cerebral palsy, neuromuscular disease, depression, or hypothyroidism. Acute causes include dehydration, electrolyte abnormalities (hypercalcemia or hypokalemia), or drug ingestions.
Constipation may still be present with a recent, watery bowel movement if the child is passing soft stool around a mass of hard stool. Pencil-like stools suggest a stricture. Spasticity or delayed motor milestones may be signs of occult spinal dysraphism. Toilet training is a common inciting event for functional constipation.
While constipation may be very painful, it should not cause an ill or toxic appearance. The abdomen may be distended, and firm columns of stool may be felt in the descending and ascending colons. A rectal exam with an empty vault and increased sphincter tone that emits a burst of gas on insertion of a finger suggests Hirschsprung's disease. Examine the anal and sacral area for tufts of hair, dimples, and lipomas, which may suggest neurologic malformations including spina bifida and tethered cord.61 An anteriorly displaced anus (more than two thirds the distance from the coccyx to the scrotal-perineal junction in males and the posterior fourchette in females) should prompt outpatient surgical referral. Fissures may cause painful defecation, leading to a cycle of retention and functional constipation. Check lower extremity tone, reflexes, and gait for signs of spasticity. Botulism from contaminated honey may present as a hypotonic child with constipation.
If the constipation is presumed to be causing acute pain, the physician may wish to treat in the ED with response guiding further evaluation (Table 130-5).62,63 Oral polyethylene glycol is as effective as enemas for outpatient treatment. Children with constipation refractory to ED management may require hospitalization for polyethylene glycol by nasogastric tube.
TABLE 130-5Treatment of Constipation in Children |Favorite Table|Download (.pdf) TABLE 130-5 Treatment of Constipation in Children
Dietary management: Fruits, vegetables, avoidance of processed foods, water or nonsugar fluids to avoid dehydration.
Glycerin suppositories: ED treatment of constipation in infants <2 years; 1 suppository × 2.
Normal saline enemas: ED treatment of acute constipation; 0–6 months, 120–150 mL; 6–18 months, 150–250 mL; 18 months–5 years, 300 mL. Enemas are most effective when held as long as possible.
Sodium phosphate enemas: ED treatment of acute constipation in children 2–11 years, 2.25-oz pediatric enema. Children >11 years, 4.5-oz adult enema. May repeat.
Polyethylene glycol (PEG): Initial treatment 1–1.5 grams/kg/d divided to two to four times per day for 3 days. Then decrease to 0.78 gram/kg/d divided daily or twice daily for maintenance therapy. Inpatient treatment for cleanout by nasogastric tube with PEG + electrolyte solution is 14–40 mL/h.
Gastroenteritis is the most common cause of abdominal pain in children of all ages (see chapter 128, Vomiting, Diarrhea, and Dehydration in Children).
NONSPECIFIC ABDOMINAL PAIN
The largest single group of children will have no definite diagnosis and will receive the diagnosis of exclusion of nonspecific abdominal pain. Patients should not be given unsubstantiated diagnoses such as gastroenteritis, gastritis, or constipation without strong support for these diagnoses. Patients discharged without a clear diagnosis should have a planned reexamination.
Acknowledgment: The authors gratefully acknowledge the contributions of Anupam B. Kharbanda and Rasha D. Sawaya, the authors of this chapter in the previous edition.