Clinical validity of ultrasound in children with suspected appendicitis

The non-visualized appendix and secondary signs on ultrasound for pediatric appendicitis in the community hospital setting

BACKGROUND

Secondary signs of appendicitis on ultrasound may aid with diagnosis in the setting of a non-visualized appendix (NVA). This role has not been shown in the community hospital setting.

MATERIALS AND METHODS

All right lower quadrant ultrasounds performed in children for clinical suspicion of appendicitis over a 5-year period in a single community hospital were evaluated. Secondary signs of inflammation including free fluid, ileus, fat stranding, abscess, and lymphadenopathy were documented. Patients were followed for 1 year for the primary outcome of appendicitis. These data were analyzed to determine the utility of secondary signs in the diagnosis of acute appendicitis when an NVA is reported.

RESULTS

Six hundred and seventeen ultrasounds were reviewed; 470 of these had an NVA. Of NVAs, 47 (10%) of patients were diagnosed with appendicitis. Sensitivity and specificity of having at least one secondary were 38.3% and 80%, respectively. The positive and negative predictive values of having at least one secondary sign were 17.3% and 92%, respectively.

CONCLUSION

These data suggest that the absence of secondary signs has a strong negative predictive value for appendicitis in the community hospital setting; however, the full utility of secondary signs may be limited in this setting.

Clinical and Ultrasonographic Diagnosis of Acute Appendicitis

Appendicitis is one of the most common acute abdominal conditions encountered in the Emergency Department. It is a surgical condition that can affect any person of any age and often with varying clinical presentations. In the majority of cases, the diagnosis is straightforward. However in some, the diagnosis requires a heightened clinical suspicion. The application of adjuvant laboratory tests and diagnostic imaging helps to reduce the associated complications, morbidity and mortality of delayed diagnosis.

Sonographically detected free appendicolith as a sign of retrocecal perforated appendicitis in a 2-year-old child

Prompt and accurate diagnosis of perforated appendicitis is crucial for proper and timely treatment. The appendix, however, cannot always be identified with sonography (US). We report the case of a 2-year-old child with atypical clinical presentation, and US detection of a free appendicolith as a sign of perforated appendicitis, without visualization of the appendix itself. Laparoscopy revealed a retrocecal, gangrenous, perforated appendix with autoamputation, fibrinopurulent peritonitis, and a free appendicolith within the abdominal fluid. US detection of a free appendicolith in a child is a very rare, but unequivocal sign of perforated appendicitis, which should be sought. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:395-398, 2016.

Pediatric appendicitis: pathophysiology and appropriate use of diagnostic imaging

Evaluating children for appendicitis can be extremely difficult, and various strategies have been developed to improve the precision of preoperative diagnosis. Among these, ultrasound and computed tomography (CT) are now widely used but remain controversial. Although CT scanning is superior to ultrasound in terms of diagnostic accuracy for appendicitis, the large dose of ionizing radiation from CT and the risk of subsequent radiation-induced malignancy (RIM) are of particular concern in pediatric patients. This article reviews the literature on the pathophysiology, morbidity and mortality of appendicitis, summarizes the data regarding pediatric imaging in appendicitis, provides a practical approach to imaging for clinicians who evaluate pediatric patients, and makes recommendations for reducing the risk of RIM in pediatric patients.

Appendiceal diameter as a predictor of appendicitis in children: improved diagnosis with three diagnostic categories derived from a logistic predictive model

OBJECTIVES

To develop and assess the performance of a diameter-based logistic predictive model and a derived 3-category interpretive scheme for the sonographic diagnosis of paediatric appendicitis.

METHODS

Appendiceal diameters were extracted from reports of ultrasound examinations in children and young adults. Data were used to generate a logistic predictive model which was used to define negative, equivocal and positive interpretive categories. Diagnostic performance of the derived 3-category interpretive scheme was compared with simulated binary interpretive schemes.

RESULTS

Six hundred forty-one appendix ultrasound reports were reviewed with appendicitis present in 181 (28.2 %). Cut-off diameters based on the logistic predictive model were ≤6 mm = normal, >6 mm-8 mm = equivocal and >8 mm = positive with appendicitis present in 2.6 % (11/428), 64.9 % (72/111) and 96.1 % (98/102) of cases in each group. These cut-offs conferred 97.2 % accuracy with 17.3 % (111/641) of cases considered equivocal. Of the binary cut-offs, a 6 mm cut-off performed best with 91.6 % accuracy. AIC analysis favoured the logistic model over the binary model for prediction of appendicitis.

CONCLUSIONS

A 3-category interpretive scheme based on a logistic predictive model provides higher accuracy in the diagnosis of appendicitis than traditional binary diameter cut-offs. Inclusion of an equivocal interpretive category more accurately reflects the probability distribution of prediction of appendicitis by ultrasound.

KEY POINTS

• Three diameter categories outperform a 6-mm cut-off to diagnose appendicitis • Three categories allow more confident exclusion of appendicitis • Three categories allow more confident diagnosis of appendicitis • Three categories more accurately reflect the probability of appendicitis by ultrasound.

Integration of ultrasound findings with Alvarado score in children with suspected appendicitis

BACKGROUND

The aim of this study was to investigate the integration of ultrasound (US) findings with Alvarado score in diagnosing or excluding acute appendicitis.

METHODS

Data were analyzed in 122 pediatric patients with suspected appendicitis who had undergone US. The US findings were classified into four groups, and the patients were classified into three groups according to Alvarado score. US results and Alvarado score were compared.

RESULTS

Alvarado score was a good predictor of appendicitis for scores ≥7.

CONCLUSION

In the case of non-visualization of the appendix without a high Alvarado score, appendicitis can be safely ruled out.

Acute abdominal pain in childhood and adolescence: assessing the impact of sonography on diagnosis and treatment

PURPOSE

To assess the impact of ultrasonography on defining the diagnostic and therapeutic pathways for pediatric patients admitted to the emergency department for acute abdominal pain.

METHODS

We performed a retrospective study of all patients aged <16 years with acute abdominal pain who underwent ultrasound examination at our Diagnostic Imaging Department from October 2010 to March 2012. We investigated for each patient the pathway following ultrasound examination and definitive diagnosis. The impact of ultrasonography was defined based on the frequency with which the information resulting from this examination confirmed or denied the diagnostic suspicion made by the emergency physician on the basis of clinical and laboratory findings.

RESULTS

In 497/729 patients (69 %), ultrasound examination did not determine variations in the diagnostic and therapeutic pathways, either because it confirmed the outcome of clinical examination and laboratory tests, or because, even addressing in the opposite direction to these, the emergency physician did not consider its result because of being particularly alarmed or sufficiently reassured by clinical examination and laboratory tests. In the remaining 232/729 cases (31 %), ultrasound examination determined an increase or a reduction of the provided care and attention (subsequently proved justified in the vast majority of cases) in spite of what was initially assessed based on clinical examination and laboratory tests.

CONCLUSIONS

The results of our retrospective study demonstrated that ultrasonography was a valuable tool in the management of pediatric patients with acute abdominal pain together with clinical examination and laboratory tests.

Ultrasound assessment of acute appendicitis in paediatric patients: methodology and pictorial overview of findings seen

Acute appendicitis is a common surgical emergency in the paediatric population. Computed tomography (CT) has been shown to have high accuracy and low operator dependence in the diagnosis of appendicitis. However, with increased concerns regarding CT usage in children, ultrasound (US) is the imaging modality of choice in patients where appendicitis is suspected. This review describes and illustrates the step-wise graded-compression technique for the visualisation of the appendix, the normal and pathological appearances of the appendix, as well as the imaging characteristics of the common differentials.

• A step-wise technique improves the chances of visualisation of the appendix.

• There are often several causes for the non-visualisation of the appendix in children.

• A pathological appendix has characteristic US signs, with several secondary features also identified.

• There are multiple common differentials to consider in the paediatric patient.

Appendix not seen: the predictive value of secondary inflammatory sonographic signs

BACKGROUND

Acute appendicitis is the most prevalent emergency surgical diagnosis in children. Although traditionally a clinical diagnosis, the diagnosis of acute appendicitis is uncertain in approximately 30% of pediatric patients. In attempts to avoid a misdiagnosis and facilitate earlier definitive care, imaging modalities such as ultrasonography have become important tools. In many pediatric studies, the absence of a visualized appendix with no secondary sonographic features has been reported as a negative study result, and a study where the appendix is not seen but demonstrates secondary features is often deemed equivocal. With ultrasound appendiceal detection rates reported at 60% to 89%, the dilemma of the nonvisualized appendix or equivocal study is frequently faced by clinicians.

OBJECTIVE

This study aimed to assess the value of the nonvisualized appendix on ultrasound and the association of secondary sonographic findings in pediatric patients with acute right lower quadrant pain undergoing ultrasound, in whom acute appendicitis was a diagnostic consideration.

METHODS

Retrospective case review of 662 consecutive children (age < 18 years) presenting to a pediatric emergency department with clinically suspected appendicitis, who had graded compression sonographic studies during the 24-month study period, was performed.

RESULTS

The appendix could not be visualized in 241 studies (37.7%). An alternate diagnosis was identified via sonography in 47 patients (19.5%). Twenty-five patients (12.9%) were taken for surgery where 17 (8.8%) had acute appendicitis confirmed via pathology. The specificity of moderate-to-large amounts of free fluid is 98%, phlegmon at 100%, pericecal inflammatory fat changes at 98%, and any free fluids with prominent lymph nodes at 81%. The odds ratio of appendicitis increases from 0.56 to 0.64 to 2.3 and 17.5, respectively, when there were 2 and 3 ultrasonographic inflammatory markers identified.

CONCLUSIONS

Although uncommonly seen, large amounts of free fluid, phlegmon, and pericecal inflammatory fat changes were very specific signs of acute appendicitis. In the absence of a distinctly visualized appendix, the presence of multiple secondary inflammatory changes provides increasing support of a diagnosis of acute appendicitis.

A critical evaluation of US for the diagnosis of pediatric acute appendicitis in a real-life setting: how can we improve the diagnostic value of sonography?

BACKGROUND

We have observed that day-to-day use of US for acute appendicitis does not perform as well as described in the literature.

OBJECTIVE

Review the diagnostic performance of US in acute appendicitis with attention to factors that influence performance.

MATERIALS AND METHODS

Retrospective review of all sonograms for acute appendicitis in children from May 2005 to May 2010 with attention to the rate of identification of the appendix, training of personnel involved and diagnostic accuracy.

RESULTS

The appendix was identified in 246/1,009 cases (24.4%), with identification increasing over time. The accuracy of US was 85-91% with 35 false-positives and 54 false-negatives. Pediatric sonographers were significantly better at identifying the appendix than non-pediatric sonographers (P < 0.0001). Increased weight was the only patient factor that influenced identification of the appendix (P = 0.006). CT use was stable over the 5 years but declined in cases where the appendix was identified by US.

CONCLUSION

In day-to-day use, US does not perform as purported in the literature. We do not visualize the appendix as often as we should and false-negative and false-positive exams are too common. To improve the diagnostic performance of this modality, involvement by experienced personnel and/or additional training is needed.

Ultrasound evaluation of skull fractures in children: a feasibility study

OBJECTIVE

The objective of this study was to investigate feasibility and evaluate test characteristics of bedside ultrasound for the detection of skull fractures in children with closed head injury (CHI).

METHODS

This was a prospective, observational study conducted in a pediatric emergency department of an urban tertiary care children's hospital. A convenience sample of children younger than 18 years were enrolled if they presented with an acute CHI, and a computed tomography (CT) scan was performed. Ultrasound was performed by pediatric emergency medicine physicians with at least 1 month of training in bedside ultrasound. Ultrasound interpretation as either positive or negative for the presence of skull fracture was compared with attending radiologist CT scan dictation. Test characteristics (sensitivity, specificity, and positive and negative predictive values) were calculated.

RESULTS

Forty-six patients were enrolled. The median age was 2 years (range, 2 months to 17 years). Eleven patients (24%) were diagnosed with skull fractures on CT scan. Bedside ultrasound had a sensitivity of 82% (95% confidence interval [CI], 48%-97%), specificity of 94% (95% CI, 79%-99%), positive predictive value of 82% (95% CI, 48%-97%), and negative predictive value of 94% (95% CI, 79%-99%).

CONCLUSIONS

Bedside ultrasonography can be used by pediatric emergency medicine physicians to detect skull fractures in children with acute CHI. Larger studies are needed to validate these findings. Future studies should investigate the role of this modality as an adjunct to clinical decision rules to reduce unnecessary CT scans in the evaluation of acute CHI in children.

Abdominal pain in children

Abdominal pain is one of the most common reasons pediatric patients seek emergency care. The emergency physician must be able to distinguish diagnoses requiring immediate attention from self-limiting processes. Pediatric patients can be challenging, particularly those who are preverbal, and therefore, the clinician must rely on a detailed history from a parent or caregiver as well as a careful physical examination in order to narrow the differential diagnosis. This article highlights several pediatric diagnoses presenting as abdominal pain, including surgical emergencies, nonsurgical diagnoses, and extraabdominal processes, and reviews the clinical presentation, diagnostic evaluation, and management of each.

Combined use of modified Alvarado score and USG in decreasing negative appendicectomy rate

INTRODUCTION

Appendicitis is notorious in its ability to simulate other conditions and in the frequency it can be mimicked by other pathologies. Despite extraordinary advances in modern radiography imaging and diagnostic laboratory investigations the accurate diagnosis of acute appendicitis remains an enigmatic challenge. Of the various commonly used diagnostic aids for appendicitis, no single test can reduce the rate of negative appendicectomy to zero.

MATERIALS AND METHODS

Fifty admitted cases of suspected appendicitis were subjected to ultrasonography (USG). All the patients were scored out of 9 according to modified Alvarado score. A treatment plan was devised according to which patients with modified Alvarado score ≥7 underwent immediate appendicectomy even if USG was negative for appendicitis and patients with score <7 underwent appendicectomy if USG was positive for appendicitis.

RESULT

84.3% of males and 44.4% of females admitted as case of suspected appendicitis had confirmed appendicitis. Due to high sensitivity (97.14%) and accuracy (92%) of our diagnostic approach, 85.71% cases of appendicitis were diagnosed in early stage, with only 8.57% perforation and abscess rate, leading to post appendicectomy complication rate of only 5.14% in our study (one wound infection and one urinary retention). We could achieve low negative appendicectomy rate of 7.14% in males and 11.11% in females and overall 8.11% in our study.

CONCLUSION

Combined use of modified Alvarado score and high frequency USG not only reduces negative appendicectomy rate but also reduces morbidity and postoperative complications.

Prospective validation of the pediatric appendicitis score in a Canadian pediatric emergency department

OBJECTIVES

Clinical scoring systems attempt to improve the diagnostic accuracy of pediatric appendicitis. The Pediatric Appendicitis Score (PAS) was the first score created specifically for children and showed excellent performance in the derivation study when administered by pediatric surgeons. The objective was to validate the score in a nonreferred population by emergency physicians (EPs).

METHODS

A convenience sample of children, 4-18 years old presenting to a pediatric emergency department (ED) with abdominal pain of less than 3 days' duration and in whom the treating physician suspected appendicitis, was prospectively evaluated. Children who were nonverbal, had a previous appendectomy, or had chronic abdominal pathology were excluded. Score components (right lower quadrant and hop tenderness, anorexia, pyrexia, emesis, pain migration, leukocytosis, and neutrophilia) were collected on standardized forms by EPs who were blinded to the scoring system. Interobserver assessments were completed when possible. Appendicitis was defined as appendectomy with positive histology. Outcomes were ascertained by review of the pathology reports from the surgery specimens for children undergoing surgery and by telephone follow-up for children who were discharged home. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated. The overall performance of the score was assessed by a receiver operator characteristic (ROC) curve.

RESULTS

Of the enrolled children who met inclusion criteria (n = 246), 83 (34%) had pathology-proven appendicitis. Using the single cut-point suggested in the derivation study (PAS 5) resulted in an unacceptably high number of false positives (37.6%). The score's performance improved when two cut-points were used. When children with a PAS of <or=4 were discharged home without further investigations, the sensitivity was 97.6% with a NPV of 97.7%. When a PAS of >or=8 determined the need for appendectomy, the score's specificity was 95.1% with a PPV of 85.2%. Using this strategy, the negative appendectomy rate would have been 8.8%, the missed appendicitis rate would have been 2.4%, and 41% of imaging investigations would have been avoided.

CONCLUSIONS

The PAS is a useful tool in the evaluation of children with possible appendicitis. Scores of <or=4 help rule out appendicitis, while scores of >or=8 help predict appendicitis. Patients with a PAS of 5-7 may need further radiologic evaluation.

US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta-Analysis

PURPOSE

To perform a meta-analysis to evaluate the diagnostic performance of ultrasonography (US) and computed tomography (CT) for the diagnosis of appendicitis in pediatric and adult populations.

MATERIALS AND METHODS

Medical literature (from 1986 to 2004) was searched for articles on studies that used US, CT, or both as diagnostic tests for appendicitis in children (26 studies, 9356 patients) or adults (31 studies, 4341 patients). Prospective and retrospective studies were included if they separately reported the rate of true-positive, true-negative, false-positive, and false-negative diagnoses of appendicitis from US and CT findings compared with the positive and negative rates of appendicitis at surgery or follow-up. Clinical variables, technical factors, and test performance were extracted. Three readers assessed the quality of studies.

RESULTS

Pooled sensitivity and specificity for diagnosis of appendicitis in children were 88% (95% confidence interval [CI]: 86%, 90%) and 94% (95% CI: 92%, 95%), respectively, for US studies and 94% (95% CI: 92%, 97%) and 95% (95% CI: 94%, 97%), respectively, for CT studies. Pooled sensitivity and specificity for diagnosis in adults were 83% (95% CI: 78%, 87%) and 93% (95% CI: 90%, 96%), respectively, for US studies and 94% (95% CI: 92%, 95%) and 94% (95% CI: 94%, 96%), respectively, for CT studies.

CONCLUSION

From the diagnostic performance perspective, CT had a significantly higher sensitivity than did US in studies of children and adults; from the safety perspective, however, one should consider the radiation associated with CT, especially in children.

Ultrasonography in the diagnosis of appendicitis: evaluation by meta-analysis

Objective

We wanted to review the usefulness of ultrasonography (US) for the diagnosis of appendicitis and to evaluate the diagnostic accuracy of US according to patients' and researchers' characteristics.

Materials and Methods

The relevant Korean articles published between 1985 and 2003 were included in this study if the patients had clinical symptoms of acute appendicitis. The histopathologic findings were the reference standard and the data were presented for 2×2 tables. Articles were excluded if patients had no sonographic signs of appendicitis according to graded-compression US. Two reviewers independently extracted the data on study characteristics. The Hasselblad method was used to obtain the combined estimates of sensitivity and specificity for the performance of US.

Results

Twenty-two articles (2,643 patients) fulfilled all inclusion criteria. The estimate of đ calculated by combining the sensitivity and specificity was 2.0054 (95% confidence interval [CI]: 1.8553, 2.1554) by a random effects model. The overall sensitivity and specificity (95% CI) were 86.7% (85.4 to 88.0), and 90.0% (88.9 to 91.2), respectively. According to the subgroup meta-analysis by patients' characteristics, the đ estimate (95% CI) of dominantly younger age, male, and highly clinical suggestive group for US was 2.2388 (1.8758 to 2.6019), 2.7131 (2.2493 to 3.1770), and 2.4582 (1.7387 to 3.1777), respectively. Also, according to subgroup meta-analysis by researchers' characteristics, the đ value (95% CI) for US done by diagnostic radiologists and gray-scale was 2.0195 (1.7942 to 2.2447) and 2.2630 (1.8444 to 2.6815).

Conclusion

This evidence suggests that US may be useful for the diagnosis of acute appendicitis, especially when patients are younger age, male, and highly clinical suggestive.

Abdominal pain in children

Abdominal pain and gastrointestinal symptoms such as vomiting or diarrhea are common chief complaints in young children who present in emergency departments. It is the emergency physician's role to differentiate between a self-limited process such as viral gastroenteritis or constipation and more life-threatening surgical emergencies. Considering the difficulties inherent in the pediatric examination, it is not surprising that appendicitis, intussusception, and malrotation with volvulus continue to be among the most elusive diagnoses. This article reviews both the self-limited and more life-threatening gastrointestinal conditions that may present in the emergency department.

Cost-effectiveness analysis of weekday and weeknight or weekend shifts for assessment of appendicitis

BACKGROUND

Assessment of appendicitis during a weeknight or weekend shift (after-hours period, AHP) might be more costly and less effective than its assessment on a weekday shift (standard hours period, SHP) because of increased costs (staff premium fees) and perforation risk (longer delays and less experience of fellows).

OBJECTIVES

The objectives were to compare the costs and effectiveness of assessing children with suspected appendicitis who required a laparotomy and had US or CT after-hours with those of assessing children during standard hours, and to evaluate the importance of diagnostic imaging (DI) within the overall costs.

MATERIALS AND METHODS

We retrospectively microcosted resource use within six areas of a tertiary hospital (emergency [ED], diagnostic imaging (DI), surgery, wards, transport, and pathology) in a tertiary hospital. About 41 children (1.8-17 years) in the AHP and 35 (2.9-16 years) in the SHP were evaluated. Work shift effectiveness was measured with a histological score that assessed the severity of appendicitis (non-perforated appendicitis: scores 1-3; perforated appendicitis: score 4).

RESULTS

The SHP was less costly and more effective regardless of whether the calculation included US or CT costs only. For a salary-based fee schedule, 733 US dollars were saved per case of perforated appendicitis averted in the SHP. For a fee-for-service payment schedule, 847 dollars were saved. Within the overall budget, the highest costs were those incurred on the ward for both shifts. The average cost per patient in DI ranged from 2 to 5% of the total costs in both shifts. Most perforation cases were found in the AHP (31.7%, AHP vs. 17.1%, SHP), which resulted in higher ward costs for patients in the AHP.

CONCLUSION

A higher proportion of severe cases was seen in the AHP, which led to its higher costs. As a result, the SHP dominated the AHP, being less costly and more effective regardless of the fee schedule applied. The DI costs contributed little to the overall cost of the assessment of appendicitis.

CT Evaluation of Appendicitis and Its Complications: Imaging Techniques and Key Diagnostic Findings

OBJECTIVE

This article reviews various CT protocols for appendicitis, identifies key CT findings for diagnosing appendicitis, discusses unusual manifestations such as chronic and recurrent appendicitis, and profiles imaging features that differentiate appendicitis from other inflammatory and neoplastic ileocecal conditions. Patients were studied with helical CT.

CONCLUSION

CT is a highly accurate, noninvasive test for appendicitis, but the optimal CT technique is controversial. Major complications of appendicitis (perforation, abscess formation, peritonitis, bowel obstruction, septic seeding of mesenteric vessels, gangrenous appendicitis) and their management are discussed. Abdominal CT is a well-established technique in the study of acute abdominal pain and has shown high sensitivity and specificity for diagnosing and differentiating appendicitis, providing an accurate diagnosis in the early stages of disease.

Using quantitative methods to improve the diagnostic workup for abdominal pain in children

INTRODUCTION

The differential diagnosis of abdominal pain in children can be challenging. We applied quantitative decision-making methods to this process and sought to determine if their use provided measurable benefit.

METHODS

After obtaining institutional review board approval, we recorded key elements of the history, physical examination, laboratory, and imaging evaluations along with the cost and the time spent in the emergency department (ED) for children presenting with abdominal pain. Initially, data were collected (group 1, n = 1366 patients) and then presented to the ED pediatricians. For subsequent patients, ED physicians received a sheet specific to that patient's age and sex reporting the most common diagnoses and the elements of the evaluation that had proven most useful (group 2, n = 624 patients). We compared the difference in length of stay and costs before and after intervention, between study groups, by age groups, and separately by sex using a 2-factor analysis of variance.

RESULTS

The diagnostic workup cost less in boys aged 2 to 12 years after the intervention. In boys and girls older than 12 years, the cost trended lower.

DISCUSSION

This study demonstrates that ED physicians equipped with specific information were able to complete their diagnostic evaluation of children presenting with abdominal pain at a lower cost.

The utility of unenhanced computed tomography in appendicitis in children

To evaluate the utility of unenhanced helical computed tomography (UHCT) in appendicitis in children, we performed a retrospective study of 112 consecutive patients. The radiologist's interpretation of the UHCT was compared with disease status using appendix pathology findings as the gold standard for diagnosis. The performance characteristics of UHCT were as follows: sensitivity 87.5% (95% CI: 75.8-94.8%), specificity 93.7% (95% CI: 85.4%-98.0%), positive predictive value 91.3% (95% CI: 83.2%-99.4%), negative predictive value 90.8% (95% CI: 83.7%-97.8%), overall diagnostic accuracy 90.9% (95% CI: 85.7-96.3%). Positive and negative likelihood ratios were 13.8 (95% CI: 5.3-35.8) and 0.13 (95% CI: 0.06-0.28), respectively. UHCT seems to be a very useful diagnostic test for the evaluation of childhood appendicitis when interpreted by experienced radiologists. The diagnostic accuracy of UHCT found in this study is comparable to that reported for contrast-enhanced CT as well as graded compression ultrasound in appendicitis in children.

Imaging the child with right lower quadrant pain and suspected appendicitis: current concepts

Acute appendicitis is the most common condition presenting with right lower quadrant pain requiring acute surgical intervention in childhood. The clinical diagnosis of acute appendicitis is often not straightforward and can be challenging. Approximately one-third of children with the condition have atypical clinical findings and are initially managed non-operatively. Complications usually result from perforation and include abscess formation, peritonitis, sepsis, bowel obstruction and death. Cross-sectional imaging with sonography and computed tomography (CT) have proven useful for the evaluation of suspected acute appendicitis in children. The principal advantages of sonography are its lower cost, lack of ionizing radiation, and ability to precisely delineate gynecologic disease. The principal advantages of CT are its operator independency with resultant higher diagnostic accuracy, enhanced delineation of disease extent in perforated appendicitis, and improved patient outcomes including decreased negative laparotomy and perforation rates.

Abdominal surgical emergencies in infants and young children

Surgical emergencies can be missed easily in children, who are not always able to volunteer relevant information. Awareness of the entities discussed in this review might help the EP uncover subtle clues to early diagnoses that might not be initially apparent. Ill-appearing children who have abdominal pain and vomiting should be considered to have ischemic or necrotic bowel until proven otherwise. Possible diagnoses include volvulus, intussusception, and necrotizing enterocolitis. Bilious vomiting, especially in a young infant, should be considered to be an indication of a high bowel obstruction such as midgut volvulus, which warrants immediate surgical consultation. Significant rectal bleeding with abdominal pain can result from intussusception, volvulus, or an inflamed Meckel's diverticulum. Rectal bleeding with unstable vital signs can result from an upper GI bleed (eg, peptic ulcer disease). Painless rectal bleeding can result from a Meckel's diverticulum, polyps, arteriovenous malformation, or a tumor. Examination of the genitalia is imperative, especially in boys, to exclude the possibility of an incarcerated hernia or testicular torsion.

Imaging of acute appendicitis in children

Acute appendicitis is the most common acute abdominal condition that results in surgical intervention in childhood. The clinical diagnosis of acute appendicitis in children can be challenging. Approximately one-third of children with the condition have atypical clinical findings and are initially managed nonoperatively. Complications associated with delayed diagnosis of this condition include perforation, abscess formation, peritonitis, sepsis, bowel obstruction, infertility, and death. The use of cross sectional imaging has proven useful for the evaluation of suspected acute appendicitis in children. Both graded compression sonography and CT have been widely utilized in the imaging assessment of the condition. The principal advantages of sonography are its lower cost, lack of ionizing radiation, and ability to assess ovarian pathology that can often mimic acute appendicitis in female patients. The principal advantages of CT include less operator dependency than sonography as reflected by a higher diagnostic accuracy, and enhanced delineation of disease extent in perforated appendicitis.

Role of imaging in the diagnosis of acute appendicitis in children

The aim of the study was to investigate the place of imaging in the diagnosis and treatment of acute appendicitis. The files of 2,427 children with suspected acute appendicitis were reviewed for clinical management and operative findings. The sample was divided into 3 groups at time of admission: (1) before diagnostic imaging was available in our department (1991-1994); (2) after the introduction of imaging studies on a random basis in equivocal cases (1995-1998); and (3) after a policy was formulated for ultrasound use in all equivocal cases followed by computed tomography if necessary (1999-2000). Results showed that the rate of misdiagnosis decreased from 13.2% in group 1 to 6.5% in group 2 and 6.1% in group 3. False-positive findings (normal appendix with positive scan) were noted in 16.7% of group 2 and 25% of group 3; false-negative findings (appendicitis at surgery with negative scan) in 23.8% and 9.5%, respectively. Computed tomography was performed in 8 children and prevented unnecessary surgery in 4 of them. We conclude that in equivocal cases of acute appendicitis, imaging studies performed by skilled operators can improve the accuracy of diagnosis, saving patients unnecessary surgery, and identifying other conditions that mimic appendicitis.

Utility of white cell count and ultrasound in the diagnosis of acute appendicitis

BACKGROUND

Despite considerable advances in imaging, the diagnosis of acute appendicitis remains a clinical one. Nonetheless, knowledge of the characteristics of commonly used investigations for appendicitis may aid surgical decision-making.

METHODS

The pathology, full blood counts and ultrasounds of 1013 patients who underwent appendicectomy were reviewed and subjected to statistical analysis in order to determine diagnostic characteristics of various white cell count and ultrasound results.

RESULTS

Total white cell count was found to be higher among patients with complicated appendicitis than those with simple appendicitis or normal appendices. Ultrasound was found to be less accurate than white cell count and neutrophil count in the diagnosis of acute appendicitis by estimation of area under the receiver operator characteristic curve.

CONCLUSION

Knowledge of the meaning of various white cell count values may be invaluable in clinical decision-making with regard to the diagnosis of acute appendicitis. Ultrasound is of limited utility in the diagnosis of appendicitis and should only be used in selected clinical situations.

Common abdominal emergencies in children

Because young children often present to EDs with abdominal complaints, emergency physicians must have a high index of suspicion for the common abdominal emergencies that have serious sequelae. At the same time, they must realize that less serious causes of abdominal symptoms (e.g., constipation or gastroenteritis) are also seen. A gentle yet thorough and complete history and physical examination are the most important diagnostic tools for the emergency physician. Repeated examinations and observation are useful tools. Physicians should listen carefully to parents and their children, respect their concerns, and honor their complaints. Ancillary tests are inconsistent in their value in assessing these complaints. Abdominal radiographs can be normal in children with intussusception and even malrotation and early volvulus. Unlike the classic symptoms seen in adults, young children can display only lethargy or poor feeding in cases of appendicitis or can appear happy and playful between paroxysmal bouts of intussusception. The emergency physician therefore, must maintain a high index of suspicion for serious pathology in pediatric patients with abdominal complaints. Eventually, all significant abdominal emergencies reveal their true nature, and if one can be patient with the child and repeat the examinations when the child is quiet, one will be rewarded with the correct diagnosis.

Pediatric appendicitis in "real-time": the value of sonography in diagnosis and treatment

OBJECTIVES

To determine the accuracy of sonography in the diagnosis of clinically equivocal appendicitis, and to identify the factors leading to an inaccurate ultrasound diagnosis. The impact of sonographic findings on clinical management and outcome of children with appendicitis is examined.

METHODS

We performed a retrospective review of 317 children who attended the emergency department (ED) of a children's hospital for acute abdominal pain for which acute appendicitis was the main differential diagnosis. They had ultrasound because the diagnosis was uncertain clinically.

RESULTS

The positive predictive value of ultrasound for appendicitis was 0.92, and the negative predictive value was 0.88. The sensitivity and specificity could not be determined because there were 43 patients with equivocal ultrasound results. The pitfalls hindering the accuracy of ultrasound diagnosis included a high incidence of perforated appendicitis at presentation, the retrocecal appendix, and other technical factors such as abdominal guarding, excessive bowel gas, obesity, inadequate bladder filling, and the uncooperative patient. When ultrasound findings were combined with clinical judgment in clinical management, there were only five cases of non-therapeutic laparotomy and eight cases of delayed surgery due to missed diagnosis in our cohort.

CONCLUSIONS

Ultrasound is a useful for the evaluation of acute abdominal pain in children. However, in the setting of a pediatric hospital ED, the accuracy of ultrasound and its ability to improve early hospital triage may be reduced. Repeated clinical review is still essential and in selected cases, appendiceal CT scan may be required to guide therapeutic decision making.

Three quantitative approaches to the diagnosis of abdominal pain in children: practical applications of decision theory

BACKGROUND/PURPOSE

The authors compared 3 quantitative methods for assisting clinicians in the differential diagnosis of abdominal pain in children, where the most common important endpoint is whether the patient has appendicitis. Pretest probability in different age and sex groups were determined to perform Bayesian analysis, binary logistic regression was used to determine which variables were statistically significantly likely to contribute to a diagnosis, and recursive partitioning was used to build decision trees with quantitative endpoints.

METHODS

The records of all children (1,208) seen at a large urban emergency department (ED) with a chief complaint of abdominal pain were immediately reviewed retrospectively (24 to 72 hours after the encounter). Attempts were made to contact all the patients' families to determine an accurate final diagnosis. A total of 1,008 (83%) families were contacted. Data were analyzed by calculation of the posttest probability, recursive partitioning, and binary logistic regression.

RESULTS

In all groups the most common diagnosis was abdominal pain (ICD-9 Code 789). After this, however, the order of the most common final diagnoses for abdominal pain varied significantly. The entire group had a pretest probability of appendicitis of 0.06. This varied with age and sex from 0.02 in boys 2 to 5 years old to 0.16 in boys older than 12 years. In boys age 5 to 12, recursive partitioning and binary logistic regression agreed on guarding and anorexia as important variables. Guarding and tenderness were important in girls age 5 to 12. In boys age greater than 12, both agreed on guarding and anorexia. Using sensitivities and specificities from the literature, computed tomography improved the posttest probability for the group from.06 to.33; ultrasound improved it from.06 to.48; and barium enema improved it from.06 to.58.

CONCLUSIONS

Knowing the pretest probabilities in a specific population allows the physician to evaluate the likely diagnoses first. Other quantitative methods can help judge how much importance a certain criterion should have in the decision making and how much a particular test is likely to influence the probability of a correct diagnosis. It now should be possible to make these sophisticated quantitative methods readily available to clinicians via the computer.

Effect of cross-sectional imaging on negative appendectomy and perforation rates in children

PURPOSE

To compare negative appendectomy and perforation rates in children who underwent ultrasonography (US), computed tomography (CT), or no imaging before urgent appendectomy.

MATERIALS AND METHODS

All children who underwent urgent appendectomy during a 4(1/2)-year period were identified in a surgical billing database. Pathology reports were coded as negative or as showing acute inflammation or perforation. Imaging up to 14 days before appendectomy or abscess drainage was noted, and imaging-based diagnoses were compared with pathologic findings. Patient age and sex were recorded.

RESULTS

Two hundred ninety-nine children, 176 (59%) male and 123 (41%) female (mean age, 10.4 years; age range, 1--21 years), underwent urgent appendectomy. One hundred twenty-six (42%) underwent no imaging, 121 (41%) underwent US with or without CT, and 52 (17%) underwent CT only; 44 (15%) underwent both US and CT. There were significantly higher rates of appendectomy with normal pathologic findings ("negative appendectomy") in patients who underwent no imaging (14% [18 of 126]) or US (17% [20 of 121]) versus the rates in those who underwent CT only (2% [one of 52]) (P =.02 and P =.007, respectively). The negative appendectomy rate was 7% in 96 patients who underwent CT with or without prior US. The perforation rates were not significantly different.

CONCLUSION

As compared with children who underwent no preoperative imaging and those who underwent US, children who underwent CT had a significantly lower negative appendectomy rate, without a significantly higher perforation rate.

The impact of ultrasound examinations on the management of children with suspected appendicitis: a 3-year analysis

BACKGROUND/PURPOSE

The aim of this study was to evaluate the usefulness of ultrasonography in the routine management of children with suspected appendicitis in a children's hospital.

METHODS

Data from surgical, radiologic, and pathologic databases were cross referenced retrospectively to allow for review of all children undergoing appendectomy and all children undergoing an ultrasound scan to rule out appendicitis in the 3-year period August 1, 1996 to July 31, 1999.

RESULTS

Pathology reports were available for 1,007 of 1,032 patients undergoing appendectomy. Eighty-four percent had acute appendicitis (26% of these were perforated). Fifty-eight percent of all children undergoing appendectomy had at least 1 preoperative ultrasound scan. Eighty-six percent of those having ultrasound scans had acute appendicitis compared with 82% of those who did not have an ultrasound scan (P <.05 chi(2) Test). During the same period, 2,056 ultrasound examinations were performed by staff radiologists who were available 24 hours a day to rule out appendicitis. Ultrasonography in this setting had a sensitivity of 89%, specificity of 95%, positive predictive value of 86%, and a negative predictive value of 96% (true-positives, n = 496; false-positive, n = 81; true-negative, n = 1,417; false-negative, n = 62). An alternate ultrasound diagnosis was offered in 157 children.

CONCLUSIONS

Ultrasound scan improves diagnostic accuracy in children with suspected appendicitis. The high negative predictive value of ultrasound scan, especially when used repeatedly, may reduce the need for admission to hospital for clinical observation to rule out appendicitis.

When appendicitis is suspected in children

Acute appendicitis is the most common condition requiring emergent abdominal surgery in childhood. The clinical diagnosis of acute appendicitis is often not straightforward because approximately one-third of children with the condition have atypical clinical findings. The delayed diagnosis of this condition has serious consequences, including appendiceal perforation, abscess formation, peritonitis, sepsis, bowel obstruction, and death. Cross-sectional imaging with ultrasonography (US) and computed tomography (CT) have proved useful for the evaluation of suspected acute appendicitis. There has been a great deal of variability in the utilization of these modalities for such diagnosis in the pediatric population. The principal advantages of US are its lower cost, lack of ionizing radiation, and ability to assess vascularity through color Doppler techniques and to provide dynamic information through graded compression. The principal advantages of CT include less operator dependency than US, as reflected by a higher diagnostic accuracy, and enhanced delineation of disease extent in a perforated appendix.

Imaging evaluation of suspected appendicitis in a pediatric population: effectiveness of sonography versus CT

OBJECTIVE

The purpose of this study was to compare the diagnostic accuracy of graded compression sonography with that of helical CT for the diagnosis of appendicitis in a pediatric and young adult population.

SUBJECTS AND METHODS

Between June 1996 and April 1999, 386 pediatric and young adult patients with suspected appendicitis were examined using sonography, CT, or both: 233 underwent sonography only, 71 underwent CT only, and 82 underwent sonography and CT. All sonograms and CT scans were prospectively interpreted as showing positive or negative findings for appendicitis by one of six pediatric radiologists. CT and sonographic findings were correlated with surgical and histopathologic findings or findings at clinical follow-up.

RESULTS

Helical CT had a significantly higher sensitivity (95% versus 78%, p = 0.009) and accuracy (94% versus 89%, p = 0.05) than graded compression sonography for the diagnosis of appendicitis in children, adolescents, and young adults. The specificity of both techniques was 93%. Twenty of 82 patients who underwent both sonography and CT had discordance between the findings of the two examinations. The CT results were correct in a significantly greater number of patients with discordant examinations (17/20 patients [85%]).

CONCLUSION

Helical CT has a significantly higher sensitivity and accuracy than graded compression sonography for the diagnosis of appendicitis in a pediatric and young adult population, particularly in children more than 10 years old.

Costs and effectiveness of ultrasonography and limited computed tomography for diagnosing appendicitis in children

BACKGROUND

A protocol of ultrasonography (US) followed by computed tomography with rectal contrast (CTRC) has been shown to be 94% accurate in the diagnosis of acute appendicitis in children.

OBJECTIVE

To evaluate the changes in patient management and costs of a protocol using US and CTRC in the evaluation of appendicitis in children.

DESIGN, SETTING, AND SUBJECTS

Prospective cohort study of 139 children between 3 and 21 years of age who had equivocal clinical findings for acute appendicitis seen in the emergency department of a large, urban pediatric teaching hospital between July 1998 and December 1998.

PROTOCOL

Children with equivocal clinical presentations for acute appendicitis were prospectively evaluated with US. Patients with positive findings for acute appendicitis went directly to the operating room. Patients with negative or equivocal findings on US underwent CTRC. Surgical management plans were recorded before imaging, after US, and after CTRC.

MAIN OUTCOME MEASURES

Surgical management plans before and after the imaging protocol as well as total hospital direct and indirect costs incurred or saved by each change in management were determined. Costs were obtained through the hospital's cost database and by ratios of costs to charges.

RESULTS

Of the 139 children, the protocol resulted in a beneficial change in management in 86 children (61.9%), no change in management in 50 children (36.0%) and an incorrect change in management in 3 children (2.1%). US alone resulted in a beneficial change in management decision in 12/31 children (38.7%), while US followed by CTRC resulted in a beneficial change in management in 74/108 children (68.5%). The protocol resulted in a total cost savings of $78 503.99 or $565/patient.

CONCLUSION

A protocol of US followed by CTRC in children with negative or equivocal US examinations results in a high rate of beneficial change in management as well as in total cost savings in children with equivocal clinical presentations for suspected appendicitis.

Appendiceal perforation in children diagnosed in a pediatric emergency department

OBJECTIVE

To determine the incidence of appendiceal perforation (AP) among children with acute appendicitis (AA) and determine factors associated with AP.

DESIGN

Retrospective chart review.

SETTING

Emergency department (ED) of Primary Children's Medical Center (PCMC).

PATIENTS

131 children less than 17 years of age with AA diagnosed in the PCMC ED.

RESULTS

The overall rate of AP was 47%. One hundred eleven (85%) children with AA were correctly diagnosed on their first ED visit. Patients with AP had a significantly (P < 0.05) lower median age (8.0 vs 11.0 years), longer duration of illness (3.0 vs 1.4 days), greater incidence of vomiting and fever by history (91% vs 69% and 83% vs 58%, respectively), higher median temperatures (39.0 degrees vs 38.3 degrees C), and higher proportions of leukocyte (WBC) band forms (14% vs 5%). Patients with AP did not differ from those without AP with respect to total WBC count, hour of arrival, or number of ED visits.

CONCLUSIONS

The rate of AP among pediatric patients with AA is greater among younger children and is associated with vomiting, prolonged illness, and higher body temperatures. Unexpectedly, patients with AP did not have higher total WBC values, more frequent late night arrivals, a longer time interval prior to surgery, or more ED visits prior to diagnosis. These findings suggest that efforts to decrease the rate of AP should be directed toward heightening awareness among primary care physicians regarding the high rate of AP in children, with an emphasis on early ED and surgical referral.

Evaluation of suspected appendicitis in children and young adults: helical CT

PURPOSE

To evaluate the accuracy of helical computed tomography (CT) for the diagnosis of appendicitis in children and to assess the utility of CT in establishing alternative diagnoses.

MATERIALS AND METHODS

The medical records of 154 children (median age, 12 years; age range, 1-20 years) who were suspected to have appendicitis and who underwent CT were reviewed. The gastrointestinal tract was opacified in 151 of 154 patients: Only orally administered contrast material was used in 126 patients; only rectally administered contrast material, in 21 patients; and both oral and rectal contrast material, in four patients. CT findings were correlated with surgical and histopathologic findings or with clinical follow-up findings.

RESULTS

Sixty-four CT scans were interpreted as positive for appendicitis and included 58 true-positive and six false-positive scans. Ninety scans were interpreted as negative and included 87 true-negative and three false-negative scans. CT had a sensitivity of 95% and a specificity of 94% for the diagnosis of appendicitis. In addition, in 32 (34%) of 93 patients without appendicitis, an alternative diagnosis was established on the basis of CT findings.

CONCLUSION

Helical CT is useful in a pediatric population to diagnose or exclude appendicitis and to establish an alternative diagnosis.

An economic evaluation of sonographic examination of children with suspected appendicitis

BACKGROUND/PURPOSE

Appendicitis is the most common surgical emergency presenting in the pediatric population. Approximately one third of these patients present with equivocal signs and symptoms frequently resulting in inpatient observation or additional diagnostic investigation. Although sonographic examination of patients with suspected appendicitis has been shown to be a highly accurate diagnostic modality, the cost effectiveness of this technology in the pediatric population has not been addressed. The economic value of this examination can be evaluated using a structured decision analysis.

METHODS

The authors constructed a decision analysis model of treatment strategies for 2 groups of patients with a suspected diagnosis of acute appendicitis. Patients were categorized as either presenting with a "definitive acute abdomen" or "equivocal examination." Data drawn from published literature reports of the sensitivity and specificity of ultrasound, institution-specific cost data, and expert judgment were used to construct 2 decision trees. These data were used to determine the least costly diagnostic strategy for each group of patients, and sensitivity analysis performed to assess the robustness of the conclusions.

RESULTS

The use of ultrasonography in patients with "an acute abdomen" is not cost efficient and results in average additional cost of $234 per patient. In patients with equivocal diagnoses who are discharged from the emergency room after a negative ultrasound examination finding results in an average cost savings of $260 when compared with admission and observation. Patients who are discharged without examination incur an average additional cost of $373 as a result of the high cost of a missed diagnosis resulting in a perforated appendix.

CONCLUSION

The use of ultrasonography can be recommended for children with suspected appendicitis and equivocal examinations who are discharged from the emergency room after a negative examination result.

Acute appendicitis in children: emergency department diagnosis and management

Early diagnosis of appendicitis in infants and children can prevent perforation, abscess formation, and postoperative complications, and can decrease cost by shortening hospitalizations. This article reviews the epidemiology, physiology, and age-specific clinical presentation of childhood appendicitis. The accuracy of diagnostic adjuncts is reviewed, as are strategies for avoiding misdiagnosis and improving emergency department evaluation and management.

Radiologists' confidence in interpretation of sonography and CT in suspected pediatric appendicitis

OBJECTIVE

We sought to determine radiologists' confidence in interpretation of sonography and CT performed using rectal contrast material for diagnosing pediatric appendicitis.

SUBJECTS AND METHODS

We prospectively examined 139 children and young adults with equivocal clinical findings for appendicitis who were seen in the emergency department of an urban pediatric teaching hospital between July and December, 1998. Patients were initially examined with pelvic sonography. If the sonographic results were equivocal or if the appendix was not visualized, CT was performed. Radiologists recorded their level of confidence in interpretation of the sonograms and CT examinations.

RESULTS

Sonography was interpreted with very low, low, or medium confidence in 59 (42.4%) of 139 patients and with high or very high confidence in 80 (57.6%) of 139. CT was interpreted with very low, low, or medium confidence in nine (8.3%) of 108 and with high or very high confidence in 99 (91.7%) of 108 children. Radiologists were more confident in their interpretation of CT than sonography (p < 0.001). If the sonography was a true-positive examination, radiologists were more confident in its interpretation than if it was a false-positive study (p = 0.003). Radiologists were more confident in sonographic interpretation of a true-negative examination than of a false-negative study (p = 0.03). Patient age and sex and the radiologists' level of experience did not make a significant difference in the confidence of interpretation of sonography or CT.

CONCLUSION

In the evaluation of childhood appendicitis, radiologists' confidence in interpretation is influenced by the choice of imaging technique as well as by the results of the study.

Diagnosing appendicitis across the life span

Arriving at a definitive diagnosis of acute appendicitis (AA) requires an understanding of the various presenting signs and symptoms of all ages and genders across the life span. Primary care providers must also be aware of the pertinent laboratory tests and imaging procedures that will assist in providing useful information toward making an accurate diagnosis of AA. Utilizing an in-depth review of the literature, this article delineates the presenting signs and symptoms of AA from children to adults to elders. It also delineates which laboratory and imaging techniques should be used for each age group as effective adjuncts in diagnosing AA.

Effect of computed tomography on patient management and costs in children with suspected appendicitis

OBJECTIVE

Children evaluated in the emergency department for possible appendicitis are often admitted for observation, despite the widespread availability of accurate diagnostic studies, particularly computed tomography (CT). We sought to establish effective and efficient strategies for using CT to diagnose and manage children with possible appendicitis.

DESIGN

Retrospective chart review and decision analysis. Setting. Emergency department of a large, urban tertiary care pediatric teaching hospital.

PATIENTS

All patients admitted from January 1996 to August 1997 for suspected appendicitis. METHOD OF ANALYSIS: Three modeled strategies were empirically applied to the retrospective cohort of patients admitted for observation. Outcomes and costs under the modeled strategies were compared with those under current practice. The three strategies were: 1) to obtain CT scans on all patients and discharge those with normal findings; 2) to obtain CT scans and admit all patients; 3) to selectively obtain CT scans on those patients with a peripheral white blood cell count >10 000/mm(3) (10 x 10(9)/L) and admit all. The sensitivity and specificity of CT for diagnosing appendicitis were determined empirically from the data. A sensitivity analysis was performed.

MAIN OUTCOME MEASURES

The number of preoperative inpatient observation days, total hospital costs, and the rates of both missed appendicitis and negative laparotomies.

RESULTS

Of 609 patients hospitalized for possible appendicitis, 287 went directly to the operating room and 14 patients had known perforation and abscess. Three hundred eight children were observed and comprised the study cohort. Of the cohort, 112 (36.4%) underwent appendectomy and 26 (23.2%) of these had a normal appendix at pathology. Three patients were discharged from the hospital after observation and were subsequently readmitted with appendicitis (missed appendicitis). Among the 75 patients who had CT performed, the sensitivity and specificity of CT were both 97%. Under the current practice strategy, the cohort collectively accumulated 487 inpatient observation days and incurred a per patient cost of $5831. All three CT strategies would have reduced the total number of inpatient observation days, operations, negative laparotomies, as well as the per patient cost. The strategy of obtaining CT scans on all patients and then admitting them had the lowest rate of missed appendicitis. The additional cost of preventing each case of missed appendicitis under this strategy compared with the strategy of obtaining CT scans and sending home those with negative findings was $150,304. Even at the lowest reported sensitivity and specificity of CT in the literature, the ordering of the three strategies remained constant and continued to reduce total cost per patient.

CONCLUSION

Compared with current practice, diagnostic strategies using CT could reduce costs and improve diagnosis, management, and outcomes for children with appendicitis.

Does early ultrasonography affect management of pediatric appendicitis? A prospective analysis

BACKGROUND

Appendicitis remains a difficult diagnosis in children. Ultrasonography is increasingly used for the diagnosis of appendicitis, although the proper clinical role for this test remains unclear.

METHODS

To evaluate the clinical utility of ultrasonography in appendicitis, the authors analyzed prospectively all children evaluated for possible appendicitis from January 1 through December 31, 1997. Children with a high clinical suspicion of appendicitis were referred for surgery (n = 122). Children with equivocal findings of appendicitis were referred for early ultrasonography (EUS) and formed the study cohort (n = 103). An initial management plan was made to operate or observe each patient, and a risk of appendicitis (doubtful, possible, probable) was assigned by a pediatric surgery fellow. EUS was then performed, and its effect on management was assessed.

RESULTS

Using clinical judgment to operate at initial presentation, the sensitivity was 38% and specificity was 95%. Using EUS alone, the sensitivity was 87% and specificity was 88%. The management of 30 of 103 patients (30%) was changed after EUS, including a decision to operate in 28 patients and a decision not to operate in two patients.

CONCLUSIONS

EUS appears to have substantial clinical utility in children with equivocal findings of appendicitis, and its use complements the clinical management. The use of EUS can improve patient care and reduce hospital resource utilization.

Selective use of ultrasonography for acute appendicitis in children

BACKGROUND

To evaluate the role of ultrasonography in children with equivocal signs of acute appendicitis, and correlate with initial clinical impression and pathological findings.

METHODS

This is a prospective evaluation of all children presenting with a possible diagnosis of appendicitis during a 14-month study period. Patients with unequivocal clinical signs of appendicitis underwent appendectomy without ultrasonography. Patients with equivocal signs had documentation of the clinical impression and subsequent abdominal ultrasound. Statistical analysis of results was performed using the chi-square test (P <0.05 significant).

RESULTS

Two hundred fifteen consecutive children were enrolled. Signs were unequivocal in 116 and equivocal in 99. Seven patients in the first group had a normal appendix at operation. Of the 99 patients with equivocal signs, there were 28 true positives, 3 false positives, 64 true negatives, and 4 false negatives. In equivocal cases, sensitivity of the initial clinical impression versus ultrasound was 50% and 88%, respectively (P <0.05). Specificity was 85% and 96%, respectively. The positive and negative predictive values improved from 63% to 90% and 78% to 94%, respectively, with the use of ultrasonography.

CONCLUSIONS

The low false positive rate (6%) in clinically obvious cases of appendicitis does not, in our opinion, warrant ultrasonography. In clinically equivocal cases, ultrasonography is a fast, sensitive, and specific diagnostic modality to diagnose or rule out appendicitis, avoiding the need for prolonged observation and/or hospitalization.

The approach to common abdominal diagnosis in infants and children

This article focuses on salient points in the evaluation of abdominal pain in infants and children. Specifically, the authors address appendicitis and abdominal pain associated with either vomiting, constipation, or gastrointestinal bleeding. A discussion of common abdominal masses, urologic, and gynecologic problems, and considerations in the evaluation of immunologically suppressed or neurologically impaired children, and children with recurrent abdominal pain is also presented. The authors establish logical, focused approaches to the initial evaluation and management of abdominal pain and suggest criteria for timely surgical referral.