Acute abdominal pain is a frequent symptom with which children present to the emergency department (ED). The main challenge is to rule out disease that necessitates surgery, especially appendicitis, without subjecting patients to unnecessary diagnostic or surgical procedures. Failing to recognize appendicitis, but also a false diagnosis of appendicitis, may lead to extra morbidity, prolonged hospital admission, and extra costs (1,2) . Frequently encountered nonsurgical conditions such as constipation, gastroenteritis, and gynecological diagnoses need to be recognized so that these patients receive appropriate treatment and do not undergo unnecessary surgery.
Multiple studies have assessed the value of signs and symptoms in children with acute abdominal pain, as reviewed by Bundy et al (3) . The incidence of appendicitis and other diagnoses, however, varies with sex and age, creating a challenge in the diagnostic process of children with acute abdominal pain (4,5) . Previous studies were often not large enough to examine differences between subgroups of the pediatric population (3) ; nonappendicitis diagnoses still form a challenge in the diagnostic process of acute abdominal pain in children.
The primary aim of this study was to describe the incidence of different discharge diagnoses, according to age and sex. The secondary aim was to investigate which children are most likely to need multiple assessments and which children are most likely to undergo unnecessary surgical procedures.
METHODS
Patients
Medical records were retrospectively reviewed for all children between the ages of 5 and 18 years who received surgical consultation for acute abdominal pain at the ED of our university medical center between January 2001 and December 2007. This group represents the majority of all children presenting to the ED with acute abdominal pain. Patients were excluded if they had serious preexistent disease in the form of malignancies, severe congenital disease, or a history of extensive abdominal surgery. They were also excluded if the letter of discharge (discharge summary) could not be retrieved.
Diagnostic Workup
Patients were primarily assessed by surgical trainees and residents employed by the Department of Surgery. During the study period more than 80 different residents worked at the ED. Senior residents and staff surgeons were asked to assess the patient when deemed necessary. The standard workup of all patients consisted of a patient history, a physical examination, and laboratory tests. The laboratory tests included complete blood cell count, electrolytes, renal function, and liver enzyme tests. Urinalysis was performed in most patients. Abdominal radiograph and ultrasound were requested according to physician preference, although the latter was not common practice for suspected appendicitis during the study period. Computed tomography (CT) was used sporadically at our medical center for children with acute abdominal pain.
Main Discharge Diagnosis
Patients received a main discharge diagnosis upon first consultation, were advised to return the following day for a reevaluation, or were admitted for in-hospital observation or treatment. The following definition was used for discharge diagnosis: if hospital admission did not take place the discharge diagnosis was the one established by the attending ED physician; if the patient was admitted to the hospital, the discharge diagnosis was the one in the letter of discharge (discharge summary).
If appendectomy had taken place, the pathology report was reviewed to confirm or reject the diagnosis of appendicitis. The entire spectrum of appendicitis, ranging from acute mucosal inflammation to gangrenous transmural appendicitis, was accepted for the diagnosis of appendicitis (6) . The discharge diagnosis of constipation was based upon the patient history, physical examination, and laboratory values, optionally augmented by abdominal radiography or by positive effect of laxatives and enemas. Urological diagnoses (mostly urinary tract infections) were based upon urinalysis, optionally augmented by ultrasonography. Gynecological diagnoses were often made by a consulting gynecologist, based upon patient history and physical examination, also optionally augmented by ultrasonography. Nonspecific abdominal pain (NSAP) was a diagnosis by exclusion. Other diagnoses consisted of a wide range of different disease entities.
Statistical Analysis
SPSS 16.0 for Windows (SPSS Inc, Chicago, IL) was used for statistical analysis of the data. Chi-square tests were used to compare proportions between groups. The exact binomial test was used to compare the number of boys and girls with different diagnoses. It was also used to compare the number of young children (5–11 years) with the number of teenagers (12–18 years) with different diagnoses.
RESULTS
During the study period 1037 children received surgical consultation for acute abdominal pain. Ninety-six children (9%) were excluded for severe comorbidity (n = 56) and inability to retrieve the letter of discharge (discharge summary, n = 40), 941 children remaining for analysis.
Of the included children, 506 (54%) were girls. The number of girls presenting to the ED increased with age, whereas the number of boys was constant for the different age periods. Appendicitis was the most common diagnosis at discharge (29%), followed by NSAP (25%) and constipation (19%). Gastroenteritis was diagnosed in 10.1% of the cases, urological disorders in 5%, and gynecological disorders in 4%. Other disorders were diagnosed in 8% of cases. These included mesenteric lymphadenitis, inflammatory bowel disease, and upper airway infections.
Sex, Age, and Main Discharge Diagnoses
The incidence of diagnoses differed between boys and girls (Table 1 ). There was a significantly higher incidence of appendicitis in boys. Girls presented significantly more often with constipation, urological diagnoses, and gynecological diagnoses. The number of girls with nonappendicitic causes of abdominal pain increased more than 3-fold from the age of 12 years (Fig. 1 A), resulting in a decrease in the proportion of appendicitis from 38% to 18% (P < 0.01). In contrast, the number of boys with nonappendicitic causes of abdominal pain decreased slightly from the age of 12 years (Fig. 1 B), resulting in an increase in the proportion with appendicitis from 31% to 42% (P < 0.05).
TABLE 1: Incidence of diagnoses in boys and girls
FIGURE 1: Appendicitis, gynecological diagnoses, and other diagnoses by age.
When comparing teenage girls with young girls (5–11 years), there was a significant increase in all diagnoses except appendicitis (Fig. 2 A). A large part of the total increase was caused by a 3-fold increase in NSAP (100 vs 30) and a 4-fold increase in constipation (86 vs 21). In teenage girls gynecological diagnoses were only found in 34 patients (9%). In boys these phenomena were not seen. On the contrary, the number of teenage boys with appendicitis was higher than that of younger boys (P = 0.01), whereas the number of boys with NSAP and constipation remained unchanged (Fig. 2 B).
FIGURE 2: Discharge diagnoses in young children and teenagers. NS = not significant; NSAP = nonspecific abdominal pain.
Imaging Studies
An abdominal radiograph was obtained in 262 children (28%). Abdominal ultrasonography was performed in 115 children (12%), and CT was performed in 15 patients (2%). Significantly more children underwent ultrasonography in the second half of the study period than in the first half (15% vs 9%, P < 0.05). There was no significant increase in the number of CT scans (2% vs 1%, not significant [NS]).
Consultations
Girls more frequently than boys required multiple ED visits before a discharge diagnosis was made (32% vs 23% of boys, P < 0.01). Teenage girls more frequently than younger girls needed multiple ED visits (33% vs 27%, NS).
Of the children who received a final diagnosis after 1 ED visit, 258/680 (38%) had appendicitis, of those who required 2 ED visits, 16/225 (7%) had appendicitis, and of those who required 3 visits 1/36 (3%) had appendicitis. In contrast, constipation was diagnosed in 112/680 (17%) children requiring 1 visit, 59/225 (26%) of those requiring 2 visits, and 12/36 (33%) of those requiring 3 ED visits. Included in these figures are 30 children who returned to the ED within 7 days without an appointment. Of these children, 10/30 had appendicitis and 11/30 had constipation.
Consultations from other specialties than pediatric surgery were requested 203 times, in 178 children (19%). Of all teenage girls 30% were referred to a different specialist, compared with 11% of teenage boys (P < 0.01). Young girls required extra consultations more often than young boys (20% vs 12%, P = 0.05). Patients were most frequently referred to the gynecology department (43%), followed by pediatrics (38%) and urology (9%). The remaining departments included internal medicine, cardiology, and neurology. In the 86 girls seen by the gynecology department, the most frequent diagnosis was NSAP (33%), followed by constipation (23%), and gynecological diagnoses occupied only third place (19%).
Negative Surgical Procedures
Surgery was performed for suspected appendicitis in 313 patients and for other reasons in 9 patients. In 55/313 children (18%) no appendicitis was present. The negative surgery rate was 36% in teenage girls versus 10% in teenage boys (P < 0.01), 10% in young girls (P < 0.01), and 11% in boys (P < 0.01). The most common alternative diagnosis after a negative procedure was NSAP (47%), followed by gynecological diagnoses (16%) and constipation (13%). None of the alternative diagnoses required surgical intervention. Of note, 5 of 7 children with constipation as alternative diagnosis were teenage girls.
Referrals
The health system in the Netherlands is such that most patients will see a general practitioner (GP) before visiting the ED. Eighty-four percent of the children were referred by a GP, whereas 10% were self-referrals. The remaining 7% were referred by another specialist or the referrer was unknown.
The distribution of diagnoses was different in the GP-referred group from that in the self-referral group (Table 2 ). In the GP-referred group, the proportion of children with appendicitis was much higher: 31% versus 14% (P < 0.01). The proportion of constipation was lower in the GP-referred group: 18% versus 28% (P < 0.05). There was also a trend toward a lower proportion of NSAP in the GP-referred group: 32% versus 24% (NS). There were no differences in age distribution between the GP-referred group and the self-referral group (data not shown).
TABLE 2: Diagnoses and method of referral
DISCUSSION
This study investigates age- and sex-related differences in the causes of acute abdominal pain in children receiving surgical consultation in the ED. Teenage girls were found to be a distinct group of patients. The proportion of teenage girls with appendicitis is much lower than that of other children. This is because of the large number of teenage girls are diagnosed as having constipation and/or NSAP. Teenage girls more frequently require multiple visits and referrals to other specialties than other children, and more frequently undergo unnecessary surgery.
Diagnostic difficulties and negative surgical explorations in adolescent and adult women have been described (7–9) and are often attributed to gynecological diagnoses (8,9) . Our study showed that gynecological diagnoses play only a minor role in the total group of teenage girls being evaluated for possible appendicitis. Even in girls for whom assessment by the gynecology department was requested, NSAP and constipation were more often diagnosed than were gynecological problems.
The validity of constipation as a diagnosis has been challenged. Ward and Hosie (10) argued that constipation should be seen as a symptom rather than as a diagnosis. We believe that constipation in the ED is in most cases a result of a shortage of dietary fiber or fluids or simply idiopathic constipation, and classification as simple constipation is justified. The relatively high incidence of constipation, 19%, at our center compared with 5% to 11% in most of the literature (11–14) may be a result of the reluctance of other physicians to view constipation as a diagnosis. Loening-Baucke and Swidsinski found constipation to be responsible for 48% of cases of acute abdominal pain in their pediatric population in a primary health care setting (15) . Our study suggests that constipation is also an important cause of acute abdominal pain in the secondary health care setting of the ED.
There is no criterion standard test for constipation. The diagnosis is made based on patient history, physical examination, abdominal x-ray, or resolution of symptoms following therapy (16) . Strict criteria such as the Rome III criteria (17) focus on chronic functional constipation, whereas the condition seen in the ED is probably acute-upon-subclinical disease. Alternatively, the Iowa criteria could be used, which are based upon the number of weekly bowel movements, fecal incontinence, large stools in the rectum, retentive posturing, and painful defecation in the last 8 weeks. Although these criteria may outperform Rome III criteria in the ED, they have not been validated for that purpose. In this retrospective study, neither the Rome III nor the Iowa criteria were used. The sole definition used in this study was the discharge diagnosis by the attending physician. The patients were seen by more than 80 different residents, so the figures were not influenced by the diagnosis of any single physician.
NSAP is ultimately a diagnosis by exclusion. In patients with NSAP there are no clear signs of infection, nor has the physician found sufficient signs and symptoms to conclude constipation; however, constipation can be present without typical symptoms, and even regular passage of stool does not exclude the condition. Especially in teenage girls, who have a slower colonic transit time than their male peers (18,19) , fecal content may amass in various segments of the colon, rather than in the ampulla. Ward and Hosie (10) also described the occurrence of abdominal pain without accompanying symptoms as a result of constipation in teenage girls. Other authors have also suggested that constipation is frequently unrecognized and have questioned the low prevalence figures presented in the literature (15,16) . A proportion of the large group of children with NSAP may actually be constipated; however, without further research this remains speculation. Future research could provide insight into how constipation may be better recognized at the pediatric ED.
Teenage girls more frequently required multiple visits to the ED and more consultations from other specialties. More important, they had a much higher rate of unnecessary surgical procedures: 36%. Large studies have shown no correlation between the negative appendectomy rate and the perforation rate (9,20) . It has, therefore, become acceptable to pursue lower negative appendectomy rates than the traditionally accepted 10%. The high rate of unnecessary surgery illustrates the challenge that teenage girls form for ED physicians. During the time period described in this study, ultrasonography was infrequently used to diagnose appendicitis in the Netherlands, in contrast to many other countries. More recently, guidelines have been adjusted and ultrasonography now plays a major role in the diagnostic workup of children with suspected appendicitis. Generally, physicians in the Netherlands are reluctant to request CT scans in children, and this is reflected by the low proportion (2%) of children in this cohort that underwent a CT scan.
The fact that constipation and NSAP were more common in self-referral patients than in GP-referred patients suggests that the GP filters out a proportion of nonsurgical patients. It is to be expected that in health systems wherein patients more frequently present directly to the ED, the proportion of children with appendicitis will be lower, and the proportion of children with constipation and NSAP will be even higher.
In conclusion, most children and adolescents with recent-onset abdominal pain do not have surgical disease. Teenage girls seem to be a distinct group, forming a challenge for ED physicians. They often require multiple ED visits and consultations from other specialties and have a much higher negative procedure rate. The proportion of teenage girls with appendicitis is low; constipation and NSAP are the main causes of abdominal pain in this group. Physicians should have a high index of suspicion of constipation when examining teenage girls with acute abdominal pain.
Acknowledgments
We are indebted to G.W. ten Tuscher, MD, PhD, for reviewing the manuscript and giving valuable advice.
REFERENCES
1. Flum DR, Koepsell T. The clinical and economic correlates of misdiagnosed appendicitis: nationwide analysis.
Arch Surg 2002;137:799–804.
2. Bijnen CL, Van Den Broek WT, Bijnen AB, et al. Implications of removing a normal appendix.
Dig Surg 2009;20:115–21.
3. Bundy DG, Byerley JS, Liles EA, et al. Does this child have appendicitis?
JAMA 2007;298:438–51.
4. Curran TJ, Muenchow SK. The treatment of complicated appendicitis in children using peritoneal drainage: results from a public hospital.
J Pediatr Surg 1993;28:204–8.
5. Rothrock SG, Skeoch G, Rush JJ, et al. Clinical features of misdiagnosed appendicitis in children.
Ann Emerg Med 1991;20:45–50.
6. Carr NJ. The pathology of acute appendicitis.
Ann Diagn Pathol 2000;4:46–58.
7. Addiss DG, Shaffer N, Fowler BS, et al. The epidemiology of appendicitis and appendectomy in the United States.
Am J Epidemiol 1990;132:910–25.
8. Borgstein PJ, Gordijn RV, Eijsbouts QA, et al. Acute appendicitis—a clear-cut case in men, a guessing game in young women. A prospective study on the role of laparoscopy.
Surg Endosc 1997;11:923–7.
9. Ponsky TA, Huang ZJ, Kittle K, et al. Hospital- and patient-level characteristics and the risk of appendiceal rupture and negative appendectomy in children.
JAMA 2004;292:1977–82.
10. Ward HC, Hosie GP. Does constipation cause abdominal pain in childhood?
J R Soc Med 1997;91:80–2.
11. Drake DP. Acute abdominal pain in children.
J R Soc Med 1980;73:641–5.
12. Jones PF. Active observation in management of acute abdominal pain in childhood.
Br Med J 1976;2:551–3.
13. Reynolds SL, Jaffe DM. Children with abdominal pain: evaluation in the pediatric emergency department.
Pediatr Emerg Care 1990;6:8–12.
14. Wang LT, Prentiss KA, Simon JZ, et al. The use of white blood cell count and left shift in the diagnosis of appendicitis in children.
Pediatr Emerg Care 2007;23:69–76.
15. Loening-Baucke V, Swidsinski A. Constipation as cause of acute abdominal pain in children.
J Pediatr 2007;151:666–9.
16. Bulloch B, Tenenbein M. Constipation: diagnosis and management in the pediatric emergency department.
Pediatr Emerg Care 2002;18:254–8.
17. Rasquin A, Di Lorenzo C, Forbes D, et al. Childhood functional gastrointestinal disorders: child/adolescent.
Gastroenterology 2006;130:1527–37.
18. Hinds JP, Stoney B, Wald A. Does gender or the menstrual cycle affect colonic transit?
Am J Gastroenterol 1989;84:123–6.
19. Meier R, Beglinger C, Dederding JP et al. Influence of age, gender, hormonal status and smoking habits on colonic transit time.
Neurogastroenterol Motil 1995;7:235–8.
20. Livingston EH. Disconnect between incidence of nonperforated and perforated appendicitis: implications for pathophysiology and management.
Ann Surg 2007;245:886–92.