Significant Causes of Pediatric Abdominal distress is suspicious for different conditions at different ages. The authors provide an age-based guide to major concerns in the and a review of three painful illnesses that may present in children of any age: , , and .

By Alex Yeats, MD, and Jon D. Mason, MD

major challenge that frequently con- a familial predisposition and a higher prevalence in fronts emergency physicians is accu- first-born males. rately diagnosing and treating children History and physical. In the first few weeks of with abdominal complaints. Although life, the infant will be asymptomatic and will appear Amost presentations are non-life-threatening, certain healthy. Subsequently, the caregiver will observe disease states have a high potential for morbidity after feeding, usually within 30 minutes of and mortality if unrecognized or not identified in each meal. After vomiting, the patient will frequently a timely manner. want to eat again. As the condition worsens, it causes Many factors contribute to the difficulty of this projectile nonbilious vomiting, which may be fre- process, most notably the variability of disease pre- quent or strenuous enough to produce the “coffee sentations and the inability of young children to ver- ground” appearance or streaks of blood that indicate balize their complaints or give an accurate history. Mallory-Weiss tears. Furthermore, abdominal pain may be the only pre- The findings depend on the senting complaint in some conditions that are rooted duration of symptoms. Early in the course, the patient in distant anatomic locations, including pharyngitis, may look well or, if vomiting has been severe, may pneumonia, urinary tract infections, diabetic keto- show signs of and weight loss. While acidosis, sickle cell crisis, and myocarditis. of a pyloric mass known as the “olive” is This article will review some of the most serious well described in the literature, it is very difficult to medical conditions causing abdominal pain in vari- palpate even for experienced practitioners. It is most ous pediatric age-groups followed by discussions of often felt after the child has vomited and is calm. appendicitis, acute gastroenteritis, and constipation, Laboratory studies and imaging. Electrolyte and which affect children of all ages. acid base status should be investigated. Upper gas- trointestinal loss of hydro- UP TO 1 YEAR chloric acid will often result >>FAST TRACK<< in hypochloremic alkalosis PYLORIC STENOSIS with concomitant hypoka- Pylorotomy by open Pyloric occurs early in life, usually between lemia. Blood urea nitrogen incision or is the definitive treatment of 2 and 5 weeks of age. The underlying problem is hy- (BUN) may be elevated as a . pertrophy of the pyloric muscle, of which the cause consequence of dehydration. is unknown. It occurs in 1 out of 250 births in a In severe alkalotic states, one 4:1 male to female ratio.1 There also appear to be should carefully monitor breathing for apnea. Indirect hyperbilirubinemia can lead to . Dr. Yeats is a senior resident in emergency medicine and Dr. Mason is a professor of emergency medicine at The imaging study of choice is . Sensi- Eastern Virginia Medical School in Norfolk, Virginia. tivities and specificities are both well above 90%.2 A www.emedmag.com JUNE 2009 | EMERGENCY MEDICINE 27 PEDIATRIC ABDOMINAL PAIN

dangerous conditions of early infancy, vol- vulus is associated with significant morbidity and mortality, making prompt recognition im- perative. Between 75% and 90% of cases of symptomatic malrotation are seen in children less than a year old; half occur within the first month of life.3 History and physical. In a child with , the most typical presentation is abdominal dis- tension associated with bilious vomiting. Other frequently encountered symptoms include feed- ing intolerance, extreme irritability, fever, and signs of shock. Parents may also give a history of blood in the stool. Typically, the child appears ill, often with signs of hemodynamic compro- mise, and is inconsolable. Peristaltic waves in the epigastrium support the diagnosis. Laboratory studies and imaging. As in any patient with signs of shock, a complete blood count (CBC), basic metabolic panel, and blood FIGURE 1. Clues to possible intussusception. Plain gas analysis should be ordered to assess for elec- radiograph reveals a paucity of gas on the left side of the trolyte abnormalities and acidosis. A high white and dilated loops of bowel on the right. blood cell count in association with acidosis is a Reproduced with permission from Rosen LM, Yamamoto LG.4 strong indication of sepsis. Stool sampling for the presence of occult bleeding is indicated. Other considerations in the initial workup in- positive result will show a pyloric diameter between clude blood and urine cultures. 10 mm and 14 mm. If the ultrasound is negative, an The classic radiographic presentation of this di- upper gastrointestinal study is often done next to rule agnosis is the “double bubble sign,” in which both out other conditions. Plain radiography may dem- duodenal and gastric air fluid levels are seen due to onstrate excessive air within the , showing it obstruction of the . Other features sug- highly distended with a prominent incisura angularis gestive of obstruction are a bowel loop overriding (the “caterpillar sign”). the and a lack or paucity of bowel gas in the Treatment. All affected infants require replenish- lower intestine (Figure 1).4 ment of intravascular volume deficits and correction Treatment. Volume resuscitation should be ini- of electrolyte abnormalities. Normal saline is the fluid tiated immediately to maintain cardiac output, and of choice for volume replacement. Once that has been surgical consultation should be promptly under- achieved, maintenance solutions will suffice. taken. As in any patient with signs of obstruction, Pylorotomy by open incision or laparoscopy is the nasogastric tube placement is necessary. definitive treatment of pyloric stenosis. The laparo- Messineo and colleagues found that the presence scopic approach is no less effective and is associated and extent of bowel necrosis largely determines mor- with shorter hospital stays. Rarely, pyloric stenosis bidity and mortality. In their investigation the survival can also be managed medically. rate was above 93% when 10% or less of bowel be- came necrotic. When 75% of bowel became necrotic, MALROTATION WITH OR the survival rate dipped to 35%.5 WITHOUT VOLVULUS In children under the age of 1 year who manifest INTUSSUSCEPTION abdominal pain, one must consider intestinal mal- Intussusception occurs when a portion of bowel rotation, with or without volvulus. One of the most telescopes into an adjacent segment, leading to ob-

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structive symptoms. The majority of cases occur in children between the ages of 6 months and 2 years. Two-thirds of cases occur before 1 year of age. The diagnosis should also be entertained in older children with certain medical conditions that predispose them to the condition. History and physical. The classic triad of ab- dominal pain, vomiting, and rectal bleeding un- fortunately is featured in only one-third of case histories.6 Conversely, del Pozo and colleagues found, only 30% to 68% of patients with findings suggestive of intussusception actually have it.2 The pain of intussusception is colicky and par- ents will describe the patient as drawing up the legs to the abdomen or kicking them into the air. Between episodes, the child will often appear well. The vomiting will frequently be nonbilious early in the course. An interesting phenomenon has been the presence of lethargy in some infants. Many clinicians have noted this finding after the pain and vomiting paroxysms have remitted.6 Simple diar- rhea has also been noted to be an early symptom. These observations are important to consider be- cause it may be tempting to ascribe the symptoms FIGURE 2. Crescent sign in intussusception. The to a benign process such as gastroenteritis. Later “telescoped” bowel leaves this sign in some radiographs. in the course, vomiting becomes bilious and, as Reproduced with permission from Yamamoto LG.8 bowel necrosis occurs, the shedding of mucosa and blood will produce the more familiar “currant jelly stool” in about half of patients. A apparent. A mass of telescoped bowel will have con- test will be positive in 75%.7 centric areas of lucency that arise from mesenteric fat Laboratory studies and imaging. In patients sus- accumulation. Other possible clues are obscurity of pected of having intussusception, one should initially the liver edge (“absent liver edge sign”); the meniscus analyze a complete blood count and basic chemistry sign, a crescent-shaped area of gas in the colonic lu- panel, focusing on BUN. Blood typing should also men at the apical section of the intussusceptum (Fig- be ordered. Stool studies should focus on presence ure 2)8; dilated loops of small bowel, and a paucity of of occult blood. The diagnosis and therapy are ra- gas in the distal colon. Conversely, a normal cecal diographically accomplished by an air contrast or gas pattern strongly points away from the diagnosis barium . of intussusception.9 >>FAST TRACK<< Abdominal radiographs and ultrasound are the Ultrasound has proved two best choices for screening, but both have signifi- to be highly sensitive and Only 30% to 68% cant limitations. The overall sensitivity of radiogra- specific for diagnosing in- of patients with 2 findings suggestive of phy ranges from 40% to 90%. Ultrasound sensitiv- tussusception. Examination intussusception actually ity is highly user-specific; thus, ultrasound may not of current literature shows have it. be appropriate in practitioners without significant sensitivities near 100% and experience in the pediatric population. specificities ranging from 88% to 100%.10,11 One of When analyzing plain radiographs, there are cer- the key benefits of ultrasound is its ability to detect tain hallmarks to look for. A good place to begin other pathological conditions that can mimic the looking is in the right upper quadrant, where a mass presentation of intussusception. As more and more or filling defect known as the “target sign” may be practitioners become skilled in the use of ultrasound, www.emedmag.com JUNE 2009 | EMERGENCY MEDICINE 29 PEDIATRIC ABDOMINAL PAIN

the use of may become limited to the treat- the intestines back to their original position has been ment of established intussusception. accomplished, the patient can be discharged to close Treatment. Initial treatment is aimed at correct- follow-up by a pediatric surgeon. If the procedure fails, ing fluid and electrolyte abnormalities. Enema is cur- surgical reduction will be necessary. rently the modality of choice for both diagnosing and treating intussusception. There is no universal 1 TO 10 YEARS consensus as to which of three main types of en- emas is best. Barium enema has the advantage of a HEMOLYTIC UREMIC SYNDROME low perforation rate (0.39%-0.7%).2 The downsides Hemolytic uremic syndrome (HUS) is a potentially of using barium are radiation exposure and the risk fatal condition that frequently causes abdominal of chemical if perforation should occur. pain. It is the most common cause of renal failure As a consequence, many institutions prefer water- in children and is seen most often in infants and soluble contrast material. The other method used is young children. Two thirds of cases are in children air insufflation, which poses a slightly higher risk of under the age of 5 years.12 perforation (2.8%).2 Given the slight chance that this While there are many factors that are implicated in will make an urgent operative proce- the pathogenesis of the condition, the result is always dure necessary, it is prudent to notify the on-call sur- a triad of acute renal failure, hemolytic microangio- geon when an air enema is about to be performed. pathic anemia, and thrombocytopenia. The precipi- It is important to note that while the vast majority tating event is a diarrheal illness in the vast majority of of cases of intussusception occur in infants, certain cases or, less commonly, an upper respiratory one. conditions do predispose older children to acquir- The most common pathogen associated with ing the condition. These include Henoch-Schönlein HUS is a subtype of Escherichia coli, O157:H7, which purpura, intestinal polyps (Peutz-Jeghers syndrome, produces a shiga toxin that affects vero cells and is familial polyposis coli, juvenile polyposis), cystic fi- therefore known as a vero toxin. Another bacterium brosis, Meckel’s diverticulum, and lymphoma. that produces a similar toxin is Shigella dysenteriae. These two bacteria have been found to be associ- INCARCERATED ated with more than two thirds of HUS cases in Diagnosing an incarcerated can be a children.13 Other bacteria implicated include Sal- challenge as its presentation can be subtle. Prema- monella, Shigella, Campylobacter, and Yersinia species. ture infants, especially boys, are at increased risk. Additionally, some viruses such as coxsackie and History and physical. These , which tend echovirus have associations with HUS. to be right-sided, are most often detected in the first History and physical. Hemolytic uremic syndrome year of life. The child typically will present with poor is described as having two subtypes referring to the feeding, irritability, vomiting and, in males, a scro- presence (D+HUS) or absence (D-HUS) of . tal mass. Therefore it is critical to fully undress the The vast majority of cases are D+HUS, with diarrhea child. If a scrotal mass is noted, the differential di- that can be bloody. The most common risk factors agnosis should include , , include eating poorly cooked beef and being exposed , inguinal , and trauma. to farm animals. Additionally, human-to-human fecal- A major error on the part of clinicians is not to oral transmission is possible. examine the groin and genitalia in a vomiting or ir- It is important to ask about urine output, which ritable infant. Removing the diaper for a complete will be greatly diminished or absent. While HUS physical examination may be all that is needed to is commonly not thought to produce neurological make this diagnosis. symptoms, seizures are possible as a consequence of Treatment. Manual reduction is often successful. high levels of BUN. The patient should be placed in Trendelenburg posi- Specific findings on the physical examination will tion and sedated with morphine or a short-acting agent often include petechiae or purpura, evidence of gas- such as midazolam. The goal is to make the child as trointestinal hemorrhage. There is a potential for comfortable as possible and minimize crying to keep cardiac involvement and one should be attentive to intra-abdominal pressure low. After a slow milking of signs of congestive heart failure.

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Laboratory studies. To establish a diagnosis, micro- Impaired nutrient absorption in IBD often retards angiopathic hemolytic anemia must be demonstrated development. Both ulcerative and Crohn’s do with the presence of schistocytes on peripheral smear. show familial trends, so it is imperative to ask about Bilirubin levels will be elevated with the unconjugated family history. form predominating. A basic metabolic panel should be The physical examination should initially focus on ordered to assess BUN, creatinine, and electrolytes. the patient’s hemodynamic status, as dehydration and When any bleeding disorder of unknown etiology anemia can be present. Extraintestinal manifestations is suspected, it is advisable to test prothombin time, such as arthritis, uveitis, and dermatologic manifes- activated partial thromboplastin time, and interna- tations (erythema nodosum or aphthous ulcers) are tional normalized ratio and to run a disseminated also possible. Erythema nodosum is an inflammation intravascular coagulation panel, all of which will be of adipose tissue that causes tender nodules, mainly normal in cases of HUS. Additional laboratory tests on the extensor surface of the lower leg. Hepatobili- that should be ordered include a urinalysis, stool an- ary disorders such as and sclerosing chol- tigen for E coli O157:H7, and liver function tests. angitis can be part of the picture. Treatment. Treatment is largely supportive. At- Laboratory studies and imaging. Initial labora- tention should focus on fluid overload and hyper- tory studies should include a CBC and a complete kalemia as in most cases of renal failure. In severe metabolic panel including liver function tests and cases, dialysis is the treatment of choice. Indications serum albumin level. If significant bleeding has oc- for dialysis include BUN above 100 mg/dL, encepha- curred, blood typing should be ordered as well. An lopathy, congestive heart failure, and hyperkalemia.12 erythrocyte sedimentation rate can be helpful, since Packed red blood cells and platelet transfusion are in- it is elevated in the vast majority of cases. Stool stud- dicated for treating anemia and thrombocytopenia. ies should also be ordered to assess for blood and Plasma exchange is sometimes employed, al- markers of inflammation. though it has not been shown to be effective. Trans- Plain abdominal films have little value in estab- fusion of fresh frozen plasma has also failed to prove lishing a diagnosis but may suggest other conditions efficacious, as has antibiotic therapy, which should be such as obstruction, colitis, or toxic . avoided in any case because it may be a predisposing Treatment. Two important considerations that factor for HUS. With aggressive supportive treat- should serve as a guide to treatment include dis- ment, survival rates are very high and renal function ease severity and history of previous IBD diagnosis. will return to normal levels in many patients. There are various classification systems to determine the severity of disease, but most are based on number 10 YEARS AND OLDER of stools per day and associated laboratory values, as shown in Table 1.12 INFLAMMATORY BOWEL DISEASE In moderate and severe cases, appropriate sup- Inflammatory bowel disease (IBD)—clinically, ulcer- portive care should be instituted with intravenous ative colitis and Crohn’s disease—was once considered hydration to maintain hemodynamic stability fol- primarily a condition of adults. However, there has lowed by hospital admission. In cases with a previ- been a recent rise in the rates of IBD in children. ously established diagnosis, care should be directed A prospective study by Kugathasan and colleagues by the patient’s gastroenterologist. demonstrated that the overall incidence of IBD was In mild cases, one can discharge the patient to less than 5 per 100,000 in patients younger than 8 close follow up with a gastroenterologist even if a years and rose sharply to 13 per 100,000 at age 8.14 diagnosis has not been officially made. However, The mean age at diagnosis was 12.5 years, and 80% patients with moderate to severe abdominal pain of cases were diagnosed after age 10. should have a surgical consultation to rule out other History and physical. The most common clini- intra-abdominal conditions that can mimic IBD. cal features of IBD are abdominal pain, diarrhea, Long-term treatment is centered around immuno- gastrointestinal bleeding, and fever. All these signs modulators and anti-inflammatory agents with the and symptoms are seen in other conditions, but the goal of reducing inflammation while keeping side ef- patient’s growth rate may offer a more specific clue. fects to a minimum. Among the most common med- www.emedmag.com JUNE 2009 | EMERGENCY MEDICINE 31 PEDIATRIC ABDOMINAL PAIN

TABLE 1. Classification of Inflammatory Bowel Disease

Severity Stools/day Signs/symptoms Laboratory values

mild <6 absence of fever absence of anemia

moderate >6 temperature >38ЊC serum protein <3.2 g/dL, hemoglobin <10 g/dL

severe >6 severe abdominal low hemoglobin, pain/cramping, fever WBC >15, hypoalbuminemia (<3.0 mg/dL)

Data extracted from Fleisher GR et al.12

ications are 5-aminosalicylate (5-ASA), 6-mercapto- purine, and infliximab. Steroid preparations, such as TABLE 2. Ondansetron Dosing methylprednisolone, are useful in acute episodes. During Oral Rehydration

Weight Ondansetron dose COMMON CONDITIONS <8 kg not established APPENDICITIS Appendicitis is the most common nontraumatic surgi- 8-15 kg 2 mg PO once cal disease of childhood. While appendicitis does oc- 15-30 kg 4 mg PO once cur in children less than 2 years old, the presentation is often different from that seen in older patients. Due to >30 kg 8 mg PO once the inability of very young patients to accurately com- PO = orally municate their symptoms, presentation is delayed and Data extracted from Ramsook et al16; Reeves JJ et al.17 perforation is more likely. Infants frequently present after perforation has occurred and peritonitis has set in. Perforation is associated with increased complica- tion rates. The most common complications are infec- gutter may produce flank pain, whereas an tion at the incision site (3%) and abscess formation pointing toward the left lower quadrant can cause (less than 5%).15 dysuria secondary to bladder irritation. >>FAST TRACK<< History and physical. Initial examination should focus on the behavior of Appendicitis is the most Older children and adults will the child. Lying still or complaining of pain while walk- common nontraumatic frequently complain initially ing should raise suspicion for peritoneal irritation. surgical disease of of vague periumbilical pain Auscultation may reveal absence of bowel sounds.1 childhood. followed by lateralization to Depending on the progression of disease, pain may the right lower quadrant be- be localized to the right lower quadrant or involve fore generalized peritonitis develops. Fever, anorexia, the entire abdomen. Guarding or rebound tender- and vomiting usually begin after the onset of pain, ness is not always reliable early in the course.15 Fever but in approximately one-third of children, vomiting and anorexia, while common, are not universal. To will be the first symptom reported by parents.15 The further complicate the diagnostic process, appendici- position of the appendix within the abdomen also tis can follow a bout of gastroenteritis, which means significantly influences where the pain will be felt. that a child with presumed gastroenteritis whose pain For example, an appendix that resides in the lateral is worsening needs vigilance and reassessment.

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TABLE 3. Physiologic vs. Functional Causes of Constipation

Age Cause Considerations

infants Hirschsprung disease difficulty in passing stool from birth, or not passing meconium within first few days of birth

infants cow’s milk insensitivity transitioning from breast milk to formula or or allergy formula to whole milk

toddlers functional start of toilet training

toddlers illness any cause of dehydration or diaper dermatitis

older children attending school reluctance to pass stool while attending school

There are a variety of examination findings that Ultrasound can also detect other pathologic condi- may aid in determining the presence of localized tions such as tubo-ovarian abscess formation, ovar- peritonitis. The most commonly noted ones include ian torsion, and cysts. the obturator, psoas, and Rovsing’s signs. However, If the sonographic findings are equivocal, a CT scan the absence of a positive result should never be used is appropriate. It performs with 87% to 100% sensitiv- to exclude the diagnosis. Other bedside tests that ity and 83% to 97% specificity12 and may be superior can be employed are the cough sign and the Markle to other methods for obese patients in particular. sign. To check for the , have the patient Treatment. Initial treatment in the emergency first stand on tiptoe and then quickly drop back to department includes correction of fluid and electro- the flat-footed stance. The test is positive if the heel lyte derangements. An initial bolus of isotonic fluid strike elicits abdominal pain. If coughing on com- of 20 mL/kg followed by maintenance therapy is of- mand provokes or exacerbates pain in the tender ten adequate. If excessive vomiting and diarrhea have area, the child has a positive cough sign. occurred, additional fluid boluses are indicated. Laboratory studies and imaging. Initial testing Rectal acetaminophen should be given if fever should include a CBC, basic metabolic panel, and is present. Intravenous analgesics should also be urinalysis. Two key points to remember are that nor- administered for patient comfort without fear that mal leukocytes do not rule out appendicitis (only subsequent abdominal exams may be unreliable. A 70% to 90% will have leukocytosis) and that ureteral broad-spectrum antibiotic such as ampicillin/sulbac- inflammation can be secondary to appendicitis, al- tam, cefoxitin, piperacillin/tazobactam, or cefotetan though a finding of more than 20 white blood cells is warranted when perforation has occurred. per high-power field makes urinary tract infection Surgical consultation is warranted in all suspected the more likely cause. cases. The surgeon may elect to observe equivocal Ultrasound and CT are the imaging modalities of cases for a period of time, employing serial abdomi- choice. Different combinations of intravenous, oral, nal exams, or to perform an . It is im- and rectal contrast are utilized and are institution- portant to be wary of signs of symptomatic improve- specific. If there is a strong suspicion of appendicitis ment. What looks like remission can actually be a on history and physical alone, no imaging studies transient effect of perforation that will be followed need to be ordered. by peritonitis and clinical deterioration. For the sake of limiting radiation exposure, ul- trasound may be the initial test of choice. Sensi- GASTROENTERITIS tivity ranges from 80% to 92% with a specificity Gastroenteritis, while mostly a benign condition in of 86% to 98%.12 The finding most suggestive of the United States, does have the potential for signifi- appendicitis is a noncompressible dilated appendix. cant morbidity and mortality related to dehydration. www.emedmag.com JUNE 2009 | EMERGENCY MEDICINE 33 PEDIATRIC ABDOMINAL PAIN

TABLE 4. Anatomic Causes of Constipation

Finding Significance

loss of anal wink (elicited by stroking motor or sensory nerve defect anal margin)

sacral dimple caudal spinal cord abnormality

fissure, pain on defecation

anterior displaced anus formation of posterior shelf causing constipation

passage of thin or ribbon-like stool anal stenosis or anal flap

The history and physical is especially important to rehydration should be instituted immediately. Differ- establish a diagnosis and assess the degree of dehy- entiating mild (3% to 5% fluid loss) from moderate dration. An attempt should be made to determine (6% to 9% loss) dehydration is more challenging. whether the cause is viral or bacterial, an important While many studies have attempted to quantify consideration for both treatment and disposition. degrees of dehydration, their methods can be im- History and physical. Important aspects in the his- practical in clinical settings. A recent meta-analysis tory that point to viral gastroenteritis include frequent determined that only decreased skin turgor, capil- watery stools in the absence of high fever and signifi- lary refill, and hyperpnea had statistically significant cant abdominal pain. In most cases of gastroenteritis, positive and negative likelihood ratios for detecting vomiting or diarrhea precede the onset of abdominal dehydration in children.5 Therefore, if a child is not discomfort. Symptoms that last longer than 14 days already classified as severely dehydrated, the presence point away from a simple viral cause and should raise of one or more of the three previously mentioned suspicion for parasitic and noninfectious etiologies. findings indicates moderate dehydration. It is also important to identify the quantity and In cases of mild to moderate dehydration, oral re- quality of both diarrhea and vomiting. Vomiting that hydration therapy may be instituted. Oral rehydra- is both predominant and persistent warrants consid- tion therapy has been credited with shorter hospital eration of gastroesophageal reflux disease, gastric stays, fewer adverse events, and a failure rate (patients outlet problems, central nervous system abnormali- requiring intravenous hydration) of only 4%.5 ties, diabetic ketoacidosis, and urinary tract infection. The type of oral rehydration solution that should Diarrhea that is bloody or mucoid makes a bacterial be used has been subject to debate, but in the United cause more likely. In such cases stool studies should States, reduced-osmolarity formulas such as Pedia- be undertaken, including culture and Gram staining lyte, Infalyte, or Naturalyte are recommended. One for fecal leukocytes. should attempt to give 50 to 100 mL/kg over 2 to Treatment. Determining the degree of dehydra- 4 hours. Essentially, 5 mL every one to two minutes tion is an important consideration in choosing a resus- will achieve adequate results. citative strategy. Indicators that can help to categorize Various antiemetics have been studied in conjunc- dehydration as mild, moderate, or severe based on per- tion with . Administration of centage of water loss include skin turgor, condition of ondansetron (Table 2) is associated with decreased mucous membranes, heart rate, respiratory rate, capil- frequency of vomiting, fewer treatment failures, and lary refill time, sunken fontanelle, sunken orbits, and fewer hospital readmissions.16,17 mental status. In severely dehydrated patients (which implies greater than 10% fluid loss), depressed level CONSTIPATION of consciousness, delayed capillary refill (exceeding Constipation (defined as infrequent or painful defeca- 2 seconds), cool, mottled extremities, sunken orbits, tion) is another very common complaint in the pediat- and tachycardia may be seen. Aggressive intravenous ric population and one that can develop at any age. It

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accounts for 3% to 5% of all visits to outpatient clinics aged with both dietary and behavioral modifications. and 35% of visits to pediatric gastroenterologists.5 Appropriate recommendations include increasing History and physical. Obtaining a thorough his- fiber and fluid intake, administering nonstimulant tory is important in determining the cause. Table 3 laxatives and lubricants such as mineral oil, and en- highlights some of the key issues at various ages. Dis- couraging regular toileting through positive rein- tinguishing between functional causes and underlying forcement. All patients with constipation need care- anatomic or physiologic problems is crucial to the as- ful follow-up with their primary care provider. Q sessment. The physical examination should focus on the anus and perineum. Table 4 lists some anatomic REFERENCES abnormalities that can cause constipation. Radiographs 1. Tintinalli JE. Backwards and forwards. J Emerg Med. 2008;35(3):237-238. can aid the diagnosis, but it is essentially clinical. 2. del-Pozo G, Albillos JC, Tejedor D, et al. Intussusception in chil- Functional constipation develops when children dren: current concepts in diagnosis and enema reduction. Radio- associate defecation with pain and consequently graphics. 1999;19(2):299-319. 3. Hebra A, Miller M. Intestinal volvulus. eMedicine Pediatrics: Gen- resist the urge to defecate. As time progresses, the eral Medicine. http://www.emedicine.com/ped/topic1205.htm. normal physiologic reflexes within the are Accessed June 3, 2009. 4. Rosen LM, Yamamoto LG. Recurrent Abdominal Pain and Vomit- lost. The result is rectal dilation and more infrequent ing in a 7-Year-Old. Radiology Cases in Pediatric Emergency passage of large stool, which further reinforces the Medicine. Vol 2, Case 8. http://www.hawaii.edu/medicine/pediat- behavior. Rectal sensitivity further declines, leading rics/pemxray/v2c08.html. Accessed June 3, 2009. 5. Messineo A, MacMillan JH, Palder SB, et al. Clinical factors to (). affecting mortality in children with malrotation of the intestine. J Patients with anatomic defects should be referred Pediatr Surg. 1992;27(10):1343-1345. 6. Chahine AA. Intussusception. eMedicine Pediatrics: Gener- to a pediatric gastroenterologist or surgeon. Those al Medicine. http://www.emedicine.com/ped/topic1208.htm. with medical conditions that can produce constipa- Accessed June 3, 2009. 7. King L. Pediatrics, Intussusception. eMedicine Emergency Medi- tion should be evaluated for corresponding signs and cine. http://www.emedicine.com/emerg/topic385.htm. Accessed symptoms. Any disease state that can lead to water June 3, 2009. loss, such as recent gastroenteritis, fever, diabetes 8. Yamamoto LG. Find the intussusception target and crescent signs. Radiology Cases in Pediatric Emergency Medicine. Vol 17, mellitus, diabetes insipidus, or renal tubular disorder, Case 18. http://www.hawaii.edu/medicine/pediatrics/pemxray/ can result in constipation. Other medical conditions v7c18.html. Accessed June 3, 2009. 9. Sargent MA, Babyn P, Alton DJ. Plain abdominal radiography that may account for constipation include hypothy- in suspected intussusception: a reassessment. Pediatr Radiol. roidism, hyperparathyroidism, and neuromuscular 1994;24(1):17-20. disorders such as cerebral palsy, myasthenia gravis, 10. Verschelden P, Filiatrault D, Garel L, et al. Intussusception in chil- dren: reliability of US in diagnosis—a prospective study. Radiol- and muscular dystrophies. ogy. 1992;184(3):741-744. Treatment. Constipation may require a multifac- 11. Shanbhogue RL, Hussain SM, Meradji M, et al. Ultrasonography is accurate enough for the diagnosis of intussusception. J Pedi- eted therapeutic approach, depending on the cause. atr Surg. 1994;29(2):324-327. For immediate symptomatic relief, stool evacuation 12. Fleisher GR, Ludwig S, Henretig FM, eds. Textbook of Pediatric should be accomplished using stool softeners, cathar- Emergency Medicine. 5th ed. Philadelphia, PA: Lippincott Wil- liams & Wilkins; 2006:218,912,913,1097,1609. tics, or enemas. Cathartics include sodium phosphate, 13. Shapiro W. Hemolytic uremic syndrome. eMedicine Emergen- magnesium citrate, and polyethylene glycol. It may cy Medicine. http://www.emedicine.com/emerg/topic238.htm. Accessed June 3, 2009. be difficult to get younger children to ingest these 14. Kugathasan S, Judd RH, Hoffmann RG, et al. Epidemiologic and substances, making the use of enemas or suppositories clinical characteristics of children with newly diagnosed inflam- matory bowel disease in Wisconsin: a statewide population- more practical. The patient’s age should dictate which based study. J Pediatr 2003;143(4):525-531. enema is used. In infants it is important to avoid tap 15. American Pediatric Surgical Association. Appendicitis. APSA’s water or soap enemas because water intoxication can Complete Parent & Family Resource Center. http://www.pediat- ricsurgerymd.org/AM/Template.cfm?Section=Resources_for_ occur; a phosphate solution is preferable. Generally, Parents&TEMPLATE=/CM/ContentDisplay. cfm&CONTENTID= in patients over 3 years of age an adult dose can be 1315. Accessed June 9, 2009. 16. Ramsook C, Sahagun-Carreon I, Kozinetz CA. et al. A randomized used, and for younger patients, one pediatric enema is clinical trial comparing oral ondansetron with placebo in chil- sufficient.12 To avoid hyperphosphatemia, phosphate dren with vomiting from acute gastroenteritis. Ann Emerg Med. enemas should not be used in dehydrated children. 2002;39(4):397-403. 17. Reeves JJ. Shannon MW, Fleisher GR. Ondansetron decreases In the absence of anatomic defects or medical vomiting associated with acute gastroenteritis: a randomized, conditions, functional constipation should be man- controlled trial. Pediatrics. 2002;109(4):e62. www.emedmag.com JUNE 2009 | EMERGENCY MEDICINE 35