Acute appendicitis in children: comparison of clinical diagnosis with ultrasound and CT imaging

Pediatric Appendicitis Score or Ultrasonography? In Search of a Better Diagnostic Tool in Indian Children with Lower Abdominal Pain

OBJECTIVES

To prospectively assess the performance of pediatric appendicitis score (PAS) in diagnosing acute appendicitis in the children with lower abdominal pain and correlated with ultrasound findings; and to assess the impact of the PAS on clinical outcome and its efficacy in differentiating between complicated and uncomplicated appendicitis.

METHODS

A prospective study was done which included cases of lower abdominal pain. Appendectomy was done for PAS ≥ 6, and diagnosis was confirmed on histopathology. A receiver operator characteristic (ROC) curve was created to assess the PAS performance. The sensitivity, specificity, and accuracy of ultrasonography in diagnosing appendicitis were assessed, and analysis of agreement between ultrasonography and PAS score was done by kappa statistics.

RESULTS

Of 260 cases with lower abdominal pain, 205 were suspected of having appendicitis. One hundred fifty-nine had PAS ≥ 6. There were 2/159 (1.26%) cases of negative appendectomies and 2/46 (4.34%) cases of missed appendicitis. The mean PAS was significantly higher in patients with appendicitis than in those without appendicitis. The area under the ROC curve was 0.9925. Sensitivity, specificity, and positive and negative predictive value of PAS were 98.74%, 95.65%, 95.7% and 95.65%, respectively. Complicated appendicitis had significantly more PAS, fever, and cough tenderness than uncomplicated appendicitis. The sensitivity and specificity of ultrasonography were 86.79% and 17.39%, respectively. Agreement between ultrasonography-proven appendicitis and PAS-dependent appendicitis was weak.

CONCLUSION

PAS has high efficacy in diagnosing acute appendicitis. Clinical outcome was more favorable with the use of PAS. Ultrasonography should be used judiciously and in combination with clinical judgment.

What is the margin of error of surgeons and radiological imaging in diagnosing acute appendicitis?

Background

Acute appendicitis is the most common emergency requiring surgical intervention in general surgery. Negative appendectomy is defined as the removal of a pathologically normal appendix.

Aim

In this study, we aimed to show our negative appendectomy rate.

Materials and Methods

This study was carried out among 2990 patients who were operated on for appendicitis between 2015-2020 at the Health Sciences University, İstanbul Kanuni Sultan Suleyman Training, and Research Hospital. Accrual and historical records of the patients were analyzed using NCSS (Number Cruncher Statistical System) 2007 Statistical Software (Utah, USA) package program. The results were evaluated at the significance level of P < 0.05.

Results

The mean age of all patients was 33. Of the patients, 1011 were women and 1979 were men. 27 of the women patients were pregnant. We requested a blood test (WBC count) and an abdominal ultrasound for all our patients who came with the complaint of abdominal pain in the right lower quadrant. Negative appendectomy was performed with ultrasonography in 622 patients with pathological diagnoses of lymphoid hyperplasia and fibrous obliteration (20.8%). We had abdominal computerized tomography (CT) for 285 patients and abdominal magnetic resonance imaging (MRI) for 16 of 27 pregnant women (59.25%) due to unclear clinical picture. Diagnostic laparoscopy was performed in 36 of the patients who underwent CT and 4 of the patients who underwent MRI since the diagnosis could not be made. We performed unnecessary appendectomy in 21.2% of the patients.

Conclusion

With the increasing clinical follow-up experience of surgeons and developing technology in radiology, our aim is to minimize the negative appendectomy rate as much as possible.

Computed tomography for diagnosis of acute appendicitis in adults

BACKGROUND

Diagnosing acute appendicitis (appendicitis) based on clinical evaluation, blood testing, and urinalysis can be difficult. Therefore, in persons with suspected appendicitis, abdominopelvic computed tomography (CT) is often used as an add-on test following the initial evaluation to reduce remaining diagnostic uncertainty. The aim of using CT is to assist the clinician in discriminating between persons who need surgery with appendicectomy and persons who do not.

OBJECTIVES

Primary objective Our primary objective was to evaluate the accuracy of CT for diagnosing appendicitis in adults with suspected appendicitis. Secondary objectives Our secondary objectives were to compare the accuracy of contrast-enhanced versus non-contrast-enhanced CT, to compare the accuracy of low-dose versus standard-dose CT, and to explore the influence of CT-scanner generation, radiologist experience, degree of clinical suspicion of appendicitis, and aspects of methodological quality on diagnostic accuracy.

SEARCH METHODS

We searched MEDLINE, Embase, and Science Citation Index until 16 June 2017. We also searched references lists. We did not exclude studies on the basis of language or publication status.

SELECTION CRITERIA

We included prospective studies that compared results of CT versus outcomes of a reference standard in adults (> 14 years of age) with suspected appendicitis. We excluded studies recruiting only pregnant women; studies in persons with abdominal pain at any location and with no particular suspicion of appendicitis; studies in which all participants had undergone ultrasonography (US) before CT and the decision to perform CT depended on the US outcome; studies using a case-control design; studies with fewer than 10 participants; and studies that did not report the numbers of true-positives, false-positives, false-negatives, and true-negatives. Two review authors independently screened and selected studies for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently collected the data from each study and evaluated methodological quality according to the Quality Assessment of Studies of Diagnostic Accuracy - Revised (QUADAS-2) tool. We used the bivariate random-effects model to obtain summary estimates of sensitivity and specificity.

MAIN RESULTS

We identified 64 studies including 71 separate study populations with a total of 10,280 participants (4583 with and 5697 without acute appendicitis). Estimates of sensitivity ranged from 0.72 to 1.0 and estimates of specificity ranged from 0.5 to 1.0 across the 71 study populations. Summary sensitivity was 0.95 (95% confidence interval (CI) 0.93 to 0.96), and summary specificity was 0.94 (95% CI 0.92 to 0.95). At the median prevalence of appendicitis (0.43), the probability of having appendicitis following a positive CT result was 0.92 (95% CI 0.90 to 0.94), and the probability of having appendicitis following a negative CT result was 0.04 (95% CI 0.03 to 0.05). In subgroup analyses according to contrast enhancement, summary sensitivity was higher for CT with intravenous contrast (0.96, 95% CI 0.92 to 0.98), CT with rectal contrast (0.97, 95% CI 0.93 to 0.99), and CT with intravenous and oral contrast enhancement (0.96, 95% CI 0.93 to 0.98) than for unenhanced CT (0.91, 95% CI 0.87 to 0.93). Summary sensitivity of CT with oral contrast enhancement (0.89, 95% CI 0.81 to 0.94) and unenhanced CT was similar. Results show practically no differences in summary specificity, which varied from 0.93 (95% CI 0.90 to 0.95) to 0.95 (95% CI 0.90 to 0.98) between subgroups. Summary sensitivity for low-dose CT (0.94, 95% 0.90 to 0.97) was similar to summary sensitivity for standard-dose or unspecified-dose CT (0.95, 95% 0.93 to 0.96); summary specificity did not differ between low-dose and standard-dose or unspecified-dose CT. No studies had high methodological quality as evaluated by the QUADAS-2 tool. Major methodological problems were poor reference standards and partial verification primarily due to inadequate and incomplete follow-up in persons who did not have surgery.

AUTHORS' CONCLUSIONS

The sensitivity and specificity of CT for diagnosing appendicitis in adults are high. Unenhanced standard-dose CT appears to have lower sensitivity than standard-dose CT with intravenous, rectal, or oral and intravenous contrast enhancement. Use of different types of contrast enhancement or no enhancement does not appear to affect specificity. Differences in sensitivity and specificity between low-dose and standard-dose CT appear to be negligible. The results of this review should be interpreted with caution for two reasons. First, these results are based on studies of low methodological quality. Second, the comparisons between types of contrast enhancement and radiation dose may be unreliable because they are based on indirect comparisons that may be confounded by other factors.

Diagnosis of acute appendicitis and clinical outcomes following laparoscopic surgery: a cohort study

BACKGROUND

The clinical assessment of appendicitis remains challenging, especially between genders and across age groups. Negative appendicectomy rates (NARs) can be as high as 43% and are significantly higher in the female population. Evidence suggests blood markers such as white blood cell count (WBC) and C-reactive protein have poor predictive value. There is a lack of regional data assessing workup and outcomes following laparoscopic appendicectomy.

METHOD

A multi-centre, retrospective study was performed. A database of adult patients undergoing laparoscopic appendicectomy at Manly and Mona Vale Hospitals (Sydney, Australia) was analysed with regard to clinical assessment and outcomes. The primary endpoint was histological confirmation of acute appendicitis (AA). Secondary endpoints were length of hospital stay, NAR, correlation between preoperative WBC and AA, and sensitivity of preoperative imaging.

RESULTS

A total of 501 patients were included in the study. AA was confirmed in 91.2% of patients. The NAR was 8.8% across all subgroups. The NAR was 12.1% in women. 95.6% of patients had preoperative imaging. There was a statistically significant relationship between WBC and length of stay (P < 0.005), with elevated WBC correlating with increasing length of stay.

CONCLUSION

We concluded that preoperative WBC when elevated can be used as a marker for AA and also as a predictor for length of stay in hospital. We would also advocate the use of preoperative imaging in young women and children.

Suspected appendicitis pathway continues to lower CT rates in children two years after implementation

BACKGROUND

We implemented a protocol to evaluate pediatric patients with suspected appendicitis using ultrasound as the initial imaging modality. CT utilization rates and diagnostic accuracy were evaluated two years after pathway implementation.

METHODS

This was a retrospective observational study of patients <18 years evaluated for suspected appendicitis. CT rates were compared before and after implementation of the protocol, and monthly CT rates were calculated to assess trends in CT utilization.

RESULTS

CT use decreased significantly following pathway implementation from 94.2% (130/138) to 27.5% (78/284; p < 0.001). Linear regression of monthly CT utilization demonstrated that CT rates continued to trend down two years after pathway implementation. Adherence to the pathway was 89.8% (255/284). Negative appendectomy rate was 2.4% (2/85) in the post-pathway period.

CONCLUSIONS

Adherence to a pathway designed to evaluate pediatric patients with suspected appendicitis using ultrasound as the primary imaging modality has led to a sustained decrease in CT use without compromising diagnostic accuracy.

Development of a Clinical Decision Support System for Pediatric Abdominal Pain in Emergency Department Settings Across Two Health Systems Within the HCSRN

BACKGROUND

Appendicitis is a common surgical emergency in children, yet diagnosis can be challenging. An electronic health record (EHR) based, clinical decision support (CDS) system called Appy CDS was designed to help guide management of pediatric patients with acute abdominal pain within the Health Care Systems Research Network (HCSRN).

OBJECTIVES

To describe the development and implementation of a clinical decision support tool (Appy CDS) built independently but synergistically at two large HCSRN affiliated health systems using well-established platforms, and to assess the tool's Triage component, aiming to identify pediatric patients at increased risk for appendicitis.

RESULTS

Despite differences by site in design and implementation, such as the use of alerts, incorporating gestalt, and other workflow variations across sites, using simple screening questions and automated exclusions, both systems were able to identify a population with similar appendicitis rates (11.8 percent and 10.6 percent), where use of the full Appy CDS would be indicated.

DISCUSSION

These 2 HCSRN sites designed Appy CDS to capture a population at risk for appendicitis and deliver CDS to that population while remaining locally relevant and adhering to organizational preferences. Despite different approaches to point-of-care CDS, the sites have identified similar cohorts with nearly identical background rates of appendicitis.

NEXT STEPS

The full Appy CDS tool, providing personalized risk assessment and tailored recommendations, is undergoing evaluation as part of a pragmatic cluster randomized trial aiming to reduce reliance on advanced diagnostic imaging. The novel approaches to CDS we present could serve as the basis for future ED interventions.

Diagnostic performance of CT for pediatric patients with suspected appendicitis in various clinical settings: a systematic review and meta-analysis

OBJECTIVE

To assess the diagnostic performance of CT for pediatric patients with suspected appendicitis in various clinical settings and the proportion of acute appendicitis on final diagnosis among equivocal CT findings.

METHODS

MEDLINE and EMBASE databases were searched until October 21, 2017, for studies investigating diagnostic performance of CT for acute appendicitis in pediatric patients confirmed by histopathologic findings and/or clinical follow-up. Pooled estimates of sensitivity and specificity were calculated using a hierarchical logistic regression modeling. The proportion of true appendicitis among patients with inconclusive CT results was obtained using fixed and random effects meta-analyses.

RESULTS

Twenty-two articles with 3396 patients were included. The pooled sensitivity and specificity were 95% (95% CI, 93-97%) and 94% (95% CI, 90-96%), respectively, and the area under the hierarchical summary receiver operating characteristic (HSROC) curve was 0.98 (95% CI, 0.96-0.99). Subgroup analyses revealed a comparable diagnostic performance in the low-dose CT group (sensitivity, 97%; specificity, 96%) and the unenhanced group (sensitivity, 95%; specificity, 95%). Other subgroups (publication year, study design, enrolled population, true appendicitis proportion, CT channel number, and slice thickness) also showed good diagnostic performance. Six studies reporting the true appendicitis proportion among patients with equivocal CT findings had pooled proportion of 17% (95% CI, 9-29%).

CONCLUSIONS

CT showed good performance for suspected appendicitis in pediatric patients under various clinical settings, including in cases with dose reduction or absence of IV contrast. The prevalence of true appendicitis among patients with equivocal appendicitis results on CTs was not low; therefore, clinical attention should not be disregarded in this population.

A Feasibility Study of Smartphone-Based Telesonography for Evaluating Cardiac Dynamic Function and Diagnosing Acute Appendicitis with Control of the Image Quality of the Transmitted Videos

Our aim was to prove the feasibility of the remote interpretation of real-time transmitted ultrasound videos of dynamic and static organs using a smartphone with control of the image quality given a limited internet connection speed. For this study, 100 cases of echocardiography videos (dynamic organ)-50 with an ejection fraction (EF) of ≥50 s and 50 with EF <50 %-and 100 cases of suspected pediatric appendicitis (static organ)-50 with signs of acute appendicitis and 50 with no findings of appendicitis-were consecutively selected. Twelve reviewers reviewed the original videos using the liquid crystal display (LCD) monitor of an ultrasound machine and using a smartphone, to which the images were transmitted from the ultrasound machine. The resolution of the transmitted echocardiography videos was reduced by approximately 20 % to increase the frame rate of transmission given the limited internet speed. The differences in diagnostic performance between the two devices when evaluating left ventricular (LV) systolic function by measuring the EF and when evaluating the presence of acute appendicitis were investigated using a five-point Likert scale. The average areas under the receiver operating characteristic curves for each reviewer's interpretations using the LCD monitor and smartphone were respectively 0.968 (0.949-0.986) and 0.963 (0.945-0.982) (P = 0.548) for echocardiography and 0.972 (0.954-0.989) and 0.966 (0.947-0.984) (P = 0.175) for abdominal ultrasonography. We confirmed the feasibility of remotely interpreting ultrasound images using smartphones, specifically for evaluating LV function and diagnosing pediatric acute appendicitis; the images were transferred from the ultrasound machine using image quality-controlled telesonography.

The Use of Clinician-Performed Ultrasonography to Determine the Treatment Method for Suspected Paediatric Appendicitis

Objective

To investigate whether the clinician-performed ultrasonography based on the specific criteria for paediatric appendicitis could decrease the negative appendectomy rate without treatment failure.

Methods

The study was a retrospective review of paediatric patients with suspected appendicitis who presented at the emergency department of a teaching hospital over a period of 18 months. The clinicians performed the ultrasound and decided whether the patients with suspected appendicitis should be referred to surgery or managed conservatively. The determinative ultrasound criteria were the presence of periappendiceal fat infiltration and/or an obstructing appendicolith.

Results

The 166 paediatric patients with suspected appendicitis underwent ultrasonography performed by clinicians on weekdays; forty (24.1%) cases with an obstructing appendicolith and/or periappendiceal fat infiltration were treated surgically, and none had a pathologically negative appendectomy, which was significantly lower than the number in the computed tomography scan group (10.4%, 11/106) on weeknights or weekends. The remaining 126 (75.8%) patients without obstructing appendicolith or periappendiceal fat infiltration were treated conservatively, regardless of their appendiceal diameter, and no patients experienced a treatment failure.

Conclusions

The clinician-performed ultrasonography bases on the strict use of above specific ultrasound criteria to determine treatment strategies for suspected paediatric appendicitis can reduce the negative appendectomies without treatment failure. (Hong Kong j.emerg.med. 2015;22:31-40)

Evaluating the risk of appendiceal perforation when using ultrasound as the initial diagnostic imaging modality in children with suspected appendicitis

BACKGROUND

Ultrasound scan has gained attention for diagnosing appendicitis due to its avoidance of ionizing radiation. However, studies show that ultrasound scan carries inferior sensitivity to computed tomography scan. A non-diagnostic ultrasound scan could increase the time to diagnosis and appendicectomy, particularly if follow-up computed tomography scan is needed. Some studies suggest that delaying appendicectomy increases the risk of perforation.

OBJECTIVE

To investigate the risk of appendiceal perforation when using ultrasound scan as the initial diagnostic imaging modality in children with suspected appendicitis.

METHODS

We retrospectively reviewed 1411 charts of children ≤17 years old diagnosed with appendicitis at two urban academic medical centers. Patients who underwent ultrasound scan first were compared to those who underwent computed tomography scan first. In the sub-group analysis, patients who only received ultrasound scan were compared to those who received initial ultrasound scan followed by computed tomography scan. Main outcome measures were appendiceal perforation rate and time from triage to appendicectomy.

RESULTS

In 720 children eligible for analysis, there was no significant difference in perforation rate between those who had initial ultrasound scan and those who had initial computed tomography scan (7.3% vs. 8.9%, p = 0.44), nor in those who had ultrasound scan only and those who had initial ultrasound scan followed by computed tomography scan (8.0% vs. 5.6%, p = 0.42). Those patients who had ultrasound scan first had a shorter triage-to-incision time than those who had computed tomography scan first (9.2 (IQR: 5.9, 14.0) vs. 10.2 (IQR: 7.3, 14.3) hours, p = 0.03), whereas those who had ultrasound scan followed by computed tomography scan took longer than those who had ultrasound scan only (7.8 (IQR: 5.3, 11.6) vs. 15.1 (IQR: 10.6, 20.6), p < 0.001). Children < 12 years old receiving ultrasound scan first had lower perforation rate (p = 0.01) and shorter triage-to-incision time (p = 0.003).

CONCLUSION

Children with suspected appendicitis receiving ultrasound scan as the initial diagnostic imaging modality do not have increased risk of perforation compared to those receiving computed tomography scan first. We recommend that children <12 years of age receive ultrasound scan first.

Time to Appendectomy and Risk of Complicated Appendicitis and Adverse Outcomes in Children

IMPORTANCE

Management of appendicitis as an urgent rather than emergency procedure has become an increasingly common practice in children. Controversy remains as to whether this practice is associated with increased risk of complicated appendicitis and adverse events.

OBJECTIVE

To examine the association between time to appendectomy (TTA) and risk of complicated appendicitis and postoperative complications.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective cohort study using the Pediatric National Surgical Quality Improvement Program appendectomy pilot database, 2429 children younger than 18 years who underwent appendectomy within 24 hours of presentation at 23 children's hospitals from January 1, 2013, through December 31, 2014, were studied.

EXPOSURES

The main exposure was TTA, defined as the time from emergency department presentation to appendectomy. Patients were further categorized into early and late TTA groups based on whether their TTA was shorter or longer than their hospital's median TTA. Exposures were defined in this manner to compare rates of complicated appendicitis within a time frame sensitive to each hospital's existing infrastructure and diagnostic practices.

MAIN OUTCOMES AND MEASURES

The primary outcome was complicated appendicitis documented at operation. The association between treatment delay and complicated appendicitis was examined across all hospitals by using TTA as a continuous variable and at the level of individual hospitals by using TTA as a categorical variable comparing outcomes between late and early TTA groups. Secondary outcomes included length of stay (LOS) and postoperative complications (incisional and organ space infections, percutaneous drainage procedures, unplanned reoperation, and hospital revisits).

RESULTS

Of the 6767 patients who met the inclusion criteria, 2429 were included in the analysis (median age, 10 years; interquartile range, 8-13 years; 1467 [60.4%] male). Median hospital TTA was 7.4 hours (range, 5.0-19.2 hours), and 574 patients (23.6%) were diagnosed with complicated appendicitis (range, 5.2%-51.1% across hospitals). In multivariable analyses, increasing TTA was not associated with risk of complicated appendicitis (odds ratio per 1-hour increase in TTA, 0.99; 95% CI, 0.97-1.02). The odds ratios of complicated appendicitis for late vs early TTA across hospitals ranged from 0.39 to 9.63, and only 1 of the 23 hospitals had a statistically significant increase in their late TTA group (odds ratio, 9.63; 95% CI, 1.08-86.17; P = .03). Increasing TTA was associated with longer LOS (increase in mean LOS for each additional hour of TTA, 0.06 days; 95% CI, 0.03-0.08 days; P < .001) but was not associated with increased risk of any of the other secondary outcomes.

CONCLUSIONS AND RELEVANCE

Delay of appendectomy within 24 hours of presentation was not associated with increased risk of complicated appendicitis or adverse outcomes. These results support the premise that appendectomy can be safely performed as an urgent rather than emergency procedure.

The Heidelberg Appendicitis Score Simplifies Identification of Pediatric Appendicitis

OBJECTIVE

To identify the factors that facilitate the diagnosis of pediatric appendicitis.

METHODS

Institutionally approved retrospective, single center analysis of all patients with acute abdominal pain was done. Medical history, symptoms, laboratory and radiologic findings of all children presenting with abdominal pain were evaluated. To identify the best predictors, uni- and multi-variate analysis were used.

RESULTS

In 2 years, 431 patients fulfilled the inclusion criteria. Data was complete in all subjects. Of these, 156 (36.2 %) suffered from appendicitis. The best discriminators for appendicitis were clinical and ultrasound features. The four best factors were identified by CART analysis (continuous abdominal pain, tenderness on the right lower quadrant, rebound tenderness and conspicuous ultrasound) and combined to the Heidelberg Appendicitis score. A positive score (>3 features) is highly predictive for acute appendicitis (PPV 89.3 %, NPV 94.9 %) and includes all cases of perforated appendicitis.

CONCLUSIONS

It is possible to predict acute appendicitis in children. The decision making process can be simplified by the proposed Heidelberg Appendicitis score, which is comprised of four factors. It has great potential to facilitate and accelerate the diagnosis of pediatric appendicitis.

Validation of a tool predicting important findings on computed tomography among Crohn's disease patients

BACKGROUND

Patients with Crohn's disease (CD) are frequently subjected to computed tomography (CT) in the emergency department (ED). This young population is at higher risk of malignancy from radiation exposure.

OBJECTIVES

We aimed to validate a decision tool predicting complications (perforation, abscess or other serious finding) on imaging at two sites.

METHODS

We conducted a retrospective review of CT outcomes among patients with CD with ED visits at two tertiary care centers. Inclusion criteria were a CT of the abdomen/pelvis with contrast and complete lab data (erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)) within 24 hours of arrival at the University of Michigan (UM) (2012-2013) and the University of Pittsburgh (UPMC) (2009-2012). Sensitivity, negative predictive value (NPV), miss rate and CT avoidance rate were calculated.

RESULTS

At UPMC (n = 210), the tool had a sensitivity of 88.9% and NPV of 98.0%, potentially saving 47.1% from CT with a miss rate of 1.0%. At UM (n = 248), the tool had a sensitivity of 90.9% and NPV of 96.0%, saving 40.3% from CT with a miss rate of 1.6%.

CONCLUSION

A decision tool using CRP and ESR predicting CT outcomes among CD patients performed well in an external validation, allowing providers to forgo CT use with a low miss rate.

Acute Appendicitis: The Reliability of Diagnosis by Clinical Assessment Alone

Background and Aims:

This prospective study aimed to review the trustworthiness of the initial clinical assessment in acute appendicitis without employment of imaging modalities, laparoscopy or any other adjunct diagnostic test.

Patients and Methods:

717 patients were operated on for appendicitis by six different surgeons. Initial clinical and laboratory examination were evaluated in relation to the intraoperative and the pathological appreciation of the appendiceal inflammation.

Results:

598 patients were found to have appendicitis, 34 a different condition, 41 had both appendicitis and an additional condition and 44 no pathology. 6% of the laparotomies and 11 % of the appendectomies were unnecessary. The severity of the inflammation correlated significantly with periumbilical pain, pain migrating to right lower quadrant, loss of appetite, fever, rebound tenderness, local rigidity, polymorphonuclear predominance on deferential, polymorhonucleosis and leukocytosis. Leukocytosis was less frequent in aged patients. All the six surgeons were found to be equally reliable, although they all underestimated the setting compared to the pathologists. Patients with a long duration of symptoms had milder forms of inflammation and increased percentage of unanticipated abdominal conditions.

Conclusions:

Appendicitis can be reliably diagnosed clinically without employment of adjunct tests. These can be reserved for equivocal cases.

MRI of the normal appendix in children: data toward a new reference standard

BACKGROUND

Magnetic resonance imaging (MRI) might prove useful in the diagnostic evaluation of pediatric appendicitis in the effort to avoid exposing children to the ionizing radiation of CT, yet there is a paucity of literature describing the normal range of appearances of the pediatric appendix on MRI.

OBJECTIVE

To investigate MRI characteristics of the normal appendix to aid in establishing a reference standard in the pediatric population.

MATERIALS AND METHODS

We conducted a retrospective study of children and young adults (≤18 years of age) who underwent lumbar spine or pelvis MRI between Jan. 1, 2013, and Dec. 31, 2013, for indications unrelated to appendicitis. Two board-certified radiologists independently reviewed all patients' MRI examinations for appendix visualization, diameter, intraluminal content signal, and presence of periappendiceal inflammation or free fluid. We used the Cohen kappa statistic and Spearman correlation coefficient to assess reader agreement on qualitative and quantitative data, respectively.

RESULTS

Three hundred forty-six patients met inclusion criteria. Both readers visualized the appendix in 192/346 (55.5%) patients (kappa = 0.88, P < 0.0001). Estimated median appendix diameter was 5 mm for reader 1 and 6 mm for reader 2 ([25th, 75th] quartiles = [5, 6] mm; range, 2-11 mm; r = 0.81, P < 0.0001). Appendix intraluminal signal characteristics were variable. Periappendiceal inflammation was present in 0/192 (0%) and free fluid in 6/192 (3.1%) MRI examinations (kappa = 1.0).

CONCLUSION

The normal appendix was seen on MRI in approximately half of pediatric patients, with a mean diameter of ~5-6 mm, variable intraluminal signal characteristics, no adjacent inflammatory changes, and rare surrounding free fluid.

Implementation of Electronic Clinical Decision Support for Pediatric Appendicitis

BACKGROUND AND OBJECTIVE

Computed tomography (CT) and ultrasound (US) are commonly used in patients with acute abdominal pain. We sought to standardize care and reduce CT use while maintaining patient safety through implementation of a multicomponent electronic clinical decision support tool for pediatric patients with possible appendicitis.

METHODS

We conducted a quasi-experimental study of children 3 to 18 years old who presented with possible appendicitis to the pediatric emergency department (ED) between January 2011 and December 2013. Outcomes were use of CT and US. Balancing measures included missed appendicitis, ED revisits within 30 days, appendiceal perforation, and ED length of stay.

RESULTS

Of 2803 patients with acute abdominal pain over the 3-year study period, 794 (28%) had appendicitis and 207 (26.1% of those with appendicitis) had a perforation. CT use during the 10-month preimplementation period was 38.8% and declined to 17.7% by the end of the study (54% relative decrease). For CT, segmented regression analysis revealed that there was a significant change in trend from the preimplementation period to implementation (monthly decrease -3.5%; 95% confidence interval: -5.9% to -0.9%; P = .007). US use was 45.7% preimplementation and 59.7% during implementation. However, there was no significant change in US or total imaging trends. There were also no statistically significant differences in rates of missed appendicitis, ED revisits within 30 days, appendiceal perforation, or ED length of stay between time periods.

CONCLUSIONS

Our electronic clinical decision support tool was associated with a decrease in CT use while maintaining safety and high quality care for patients with possible appendicitis.

Pediatric appendiceal ultrasound: accuracy, determinacy and clinical outcomes

BACKGROUND

Ultrasonography is considered the most appropriate initial imaging study in the evaluation of acute appendicitis in children but has recently come under criticism with reports of low specificity and high indeterminate study rates, particularly when used in obese patients and patients early in the course of their disease, or when performed by sonographers with limited experience.

OBJECTIVE

To (1) assess the impact of patient factors (gender, age, body mass index, and symptom duration) and system factors (call status or year of exam) on pediatric appendiceal US accuracy and indeterminate study rate, (2) assess the impact of indeterminate study results on follow-up CT and negative laparotomy rates and (3) present strategies to reduce the rate of indeterminate US studies and improve accuracy.

MATERIALS AND METHODS

We retrospectively reviewed all US reports performed for the assessment of acute appendicitis in children <18 years old at Mayo Clinic Rochester from January 2010 to June 2014.

RESULTS

A total of 790 US examinations were performed in 452 girls (57%) and 338 boys (43%). The prevalence of appendicitis was 18.5% (146/790). There were 109 true-positive, 440 true-negative, 17 false-positive, 6 false-negative, 218 equivocal and 41 technically inadequate US studies. A definitive interpretation was made in 72% of the studies, with an accuracy, sensitivity and specificity of 0.960, 0.948 and 0.963, respectively. No patient or system factors significantly affected US accuracy. Indeterminate studies (28%) had significantly higher CT utilization (46% vs. 11%) and normal appendectomy rates (6.9% vs. 3.5%).

CONCLUSION

US should be the initial imaging study of choice for pediatric appendicitis. When a definitive interpretation was given, the accuracy was 96%, was independent of patient and system factors and resulted in reduced follow-up CTs and negative laparotomies. Accuracy can be increased by requiring the presence of periappendiceal inflammatory changes prior to interpreting a mildly distended appendix as positive for acute appendicitis. The indeterminate study rate can be reduced by not requiring visualization of the normal appendix for the exclusion of acute appendicitis.

Contrast-enhanced multidetector-row computed tomography can predict pathological findings of acute appendicitis in children

Aims

To retrospectively evaluate the correlation between multidetector-row computed tomography findings of acute appendicitis and the pathological status of acute appendicitis, and evaluate the capability of multidetector-row computed tomography to predict the pathological status of acute appendicitis in children.

Methods

The presence of a distended appendix (>6 mm in transverse diameter) was used as a primary sign to indicate the presence of appendiceal inflammation. The presence of appendiceal wall thickening (>1 mm) and enhanced appendiceal wall continuity were also used as predictive findings to reflect the degree of progression of acute appendicitis on multidetector-row computed tomography findings. The findings of each individual case were classified into four grades. The final pathological diagnosis was classified into four groups: normal findings, only mucosal inflammation, inflammation with intramural spreading, and gangrenous. The relationship between the pathological grades and computed tomography grades was analyzed using Spearman's rank correlation test.

Results

Four of six cases in Grade 0 reflected normal appendiceal findings (66.7%) and 3 of 5 cases in Grade I reflected only mucosal inflammation status (60.0%). Forty-four of 51 cases in Grade II reflected intramural inflammation status (86.3%), and 40 of 57 cases in Grade III reflected gangrenous status (70.2%). The multidetector-row computed tomography grade was significantly correlated to the pathological grade with Spearman's rank correlation coefficient of 0.689 (P < 0.001).

Conclusions

There was a close relationship between the multidetector-row computed tomography imaging findings and the pathological findings. This preoperative information is extremely useful for decision-making in the treatment strategy for acute appendicitis in children.

Less negative appendectomies due to imaging in patients with suspected appendicitis

BACKGROUND

The optimal diagnostics and treatment of acute appendicitis continues to be a challenge. We evaluated the implementation of the guideline "diagnostics and treatment in acute appendicitis" in 2010. This guideline states that, in every patient with clinically suspected acute appendicitis, an ultrasonography or CT scan is advised to confirm the diagnosis before surgery.

PATIENTS AND METHODS

We selected all consecutive patients with acute appendicitis in our hospital in the years 2008 and 2011. We compared the use of imaging and the operation results in both years.

RESULTS

In 2008, 228 patients were treated for acute appendicitis. In 43 %, imaging was performed. In 2011, 238 patients were treated; in 99 % of the cases, imaging was performed. A decrease in patients with negative appendectomy was seen from 19 % in 2008 to 5 % in 2011. Financial analysis showed a reduction in costs favoring 2011.

CONCLUSIONS

The increased use of pre-operative imaging in patients with suspected acute appendicitis resulted in a cost-effective way to decrease the number of patients with negative appendectomies.

Utility of CT after sonography for suspected appendicitis in children: integration of a clinical scoring system with a staged imaging protocol

To improve diagnosis of pediatric appendicitis, many institutions have implemented a staged imaging protocol utilizing ultrasonography (US) first and then computed tomography (CT). A substantial number of children with suspected appendicitis undergo CT after US, and the efficient and accurate diagnosis of pediatric appendicitis continues to be challenging. The objective of the study is to characterize the utility of CT following US for diagnosis of pediatric appendicitis, in conjunction with a clinical appendicitis score (AS). Imaging studies of children with suspected appendicitis who underwent CT after US in an imaging protocol were retrospectively reviewed by three radiologists in consensus. Chart review derived the AS (range 0-10) and obtained the patient diagnosis and disposition, and an AS was applied to each patient. Clinical and radiologic data were analyzed to assess the yield of CT after US. Studies of 211 children (mean age 11.3 years) were included. The positive threshold for AS was determined to be 6 out of 10. When AS and US were concordant (N = 140), the sensitivity and specificity of US were similar to CT. When AS and US were discordant (N = 71) and also when AS ≥ 6 (N = 84), subsequent CT showed superior sensitivity and specificity to US alone. In the subset where US showed neither the appendix nor inflammatory change in the right lower quadrant (126/211, 60 % of scans), when AS < 6 (N = 83), the negative predictive value (NPV) of US was 0.98. However, when AS ≥ 6 (N = 43), NPV of US was 0.58, and the positive predictive value of subsequent CT was 1. There was a significant decrease in depiction of the appendix on US with patient weight-to-age ratio of >6 (kg/year, P < 0.001) and after-hours (1700 -0730 hours) performance of US (P < 0.001). Results suggest that the appendicitis score has utility in guiding an imaging protocol and support the contention that non-visualization of the appendix on US is not intrinsically non-diagnostic. There was little benefit to additional CT when AS < 6 and US did not show the appendix or evidence of inflammation; this would have avoided CT in 140/211 (66 %) patients. CT demonstrated benefit when AS ≥ 6, suggesting that cases with AS ≥ 6 and features that limit depiction of the appendix on US may be triaged to CT.

Do clinical outcomes suffer during transition to an ultrasound-first paradigm for the evaluation of acute appendicitis in children?

OBJECTIVE

The objective of our study was to examine whether the rate of complicated appendicitis and the hospital length of stay (LOS) increased during the transition to an ultrasound-first paradigm for the imaging evaluation of acute appendicitis.

MATERIALS AND METHODS

All pediatric patients with surgically proven appendicitis from 2005 to 2011 were identified by searching the hospital billing database for the discharge diagnosis codes for simple appendicitis (ICD-9 [International Classification of Diseases, 9th revision] code 540.9) and complicated appendicitis (ICD-9 codes 540.0 and 540.1). Annual trends of the proportions of these patients who underwent ultrasound and CT were determined and plotted for the study period. Correlation of complicated appendicitis and median hospital LOS with calendar year was assessed using the Spearman (ρ) rank correlation test. RESULTS. Eight hundred four patients met the inclusion criteria. The percentage of patients who underwent CT only showed a moderate downward association with year (ρ = -0.32, p < 0.01), and the percentage of patients who underwent ultrasound first showed a moderate upward trend (ρ = 0.44, p < 0.01). The percentage of patients with ultrasound as the only study performed before appendectomy increased moderately over the 7-year study period (ρ = 0.33, p < 0.01). The percentage of patients with complicated appendicitis and the median hospital LOS did not increase significantly over the study duration (ρ = -0.01, p = 0.74 and ρ = -0.04, p = 0.25, respectively).

CONCLUSION

The transition to an ultrasound-first pathway for the imaging workup of acute appendicitis in children occurred without evidence of a corresponding increase in the proportion of patients with complicated appendicitis or in the median hospital LOS.

How do you diagnose appendicitis? An international evaluation of methods

INTRODUCTION

Considerable variability exists in the diagnostic approach to acute appendicitis (in children), affecting both quality and costs of care. Interestingly, an international evaluation of what is commonly practiced today has not been performed. We aimed to document current practice patterns in the diagnosis of appendicitis in children and to determine whether a consensus exists in the workup of these patients among Canadian, Dutch, and Saudi Arabian pediatric surgeons.

METHODS

We performed a cross-sectional survey using a pre-designed, self-administered, 14-item survey. We sent the survey to participants via electronic mail.

RESULTS

In total, 83 responses were received and analyzed, yielding a response rate of 42%. The majority of respondents practiced at pediatric surgery centers with over 50 beds (58% of Canadian surgeons, 81% of Dutch surgeons, 93% of Saudi Arabian surgeons). The majority of Dutch surgeons had a preference for physical examination and radiological imaging as opposed to Canadian and Saudi Arabian surgeons who favored history and physical examination. Interestingly, only one of the surgeons surveyed used an appendicitis scoring system. Regarding history and physical examination, most respondents deemed migratory abdominal pain and localized RLQ tenderness to be most suggestive of appendicitis. Ultrasound was the most preferable imaging modality in acute appendicitis across all three countries.

CONCLUSION

This study demonstrates that international pediatric surgeons vary substantially in the diagnostic workup of patients with appendicitis. Furthermore, there is a variability between common practice and the current evidence. We recommend that pediatric surgeons develop clinical practice guidelines that are based on consensus information (expert opinion) and the best available literature.

Managing radiation exposure in children--reexamining the role of ultrasound in the diagnosis of appendicitis

PURPOSE

To assess the efficacy and accuracy of ultrasonography (US) and selective computed tomography (CT) in the diagnosis of acute appendicitis in children.

METHODS

A retrospective review of all ultrasound evaluations for appendicitis from July 1, 2003, to June 30, 2010, was conducted at two urban pediatric centers. Beginning in 2003, a multi-disciplinary diagnostic protocol was implemented to reduce radiation exposure employing US as the initial imaging modality followed by CT for non-diagnostic US studies in patients with an equivocal clinical presentation. The imaging, operative findings, and pathology of 802 patients (365 females, 437 males, age less than 18 years) with suspected appendicitis were reviewed. The sensitivity, specificity, predictive value, and negative appendectomy rate of the protocol were analyzed. A telephone survey was conducted of patients discharged without a diagnosis of appendicitis to evaluate the missed appendicitis rate.

RESULTS

Of the 601 pediatric appendectomies performed, a total of 275 (46%) were diagnosed by protocol. The selective protocol had a sensitivity of 94.2%, specificity of 97.5%, positive predictive value of 95.2%, and negative predictive value of 97.0%. The negative appendectomy rate was 1.82%, and the missed appendicitis rate was 0%. No patient discharged after only ultrasound evaluation without undergoing surgery reported missed appendicitis on the survey (41.7% response rate). Protocol use increased from 6.7% to 88.3%. US was the sole imaging modality in 630 of all 802 patients (78.6%).

CONCLUSIONS

US followed by selective CT for the diagnosis of acute appendicitis is useful and accurate. This has important implications in the reduction of childhood radiation exposure.

Ultrafast 3-T MRI in the evaluation of children with acute lower abdominal pain for the detection of appendicitis

OBJECTIVE

The purpose of this study is to evaluate the feasibility of ultrafast 3-T MRI in the evaluation of children with acute lower abdominal pain for the detection of appendicitis.

SUBJECTS AND METHODS

Forty-two pediatric patients (30 girls and 12 boys; mean age, 11.5 years; age range, 4-17 years) with acute abdominal pain were prospectively studied. Ultrafast 3-T MRI was performed with a three-plane single-shot turbo spin-echo sequence and an axial T2-weighted turbo spin-echo sequence with fat suppression. All scans were performed without sedation or oral or IV contrast agent. Scan times were less than 8 minutes 45 seconds (median, 5 minutes 40 seconds). Patients underwent CT or ultrasound or both as a comparison study to the MRI examination. The MRI, CT, and ultrasound examinations were interpreted independently by four board-certified radiologists who were blinded to patient information, study interpretations, surgical pathologic findings, and final diagnosis.

RESULTS

Twelve of 42 cases of acute appendicitis were detected with 100% sensitivity, 99% specificity, 100% negative predictive value, and 98% positive predictive value, all of which were statistically significant (p < 0.01). The pooled and individual receiver operating characteristic curves for radiologists' interpretation of the diagnosis of acute appendicitis were greater than 0.95 in all cases (p < 0.01)

CONCLUSION

Ultrafast 3-T MRI is a feasible alternative imaging modality for the diagnosis of acute appendicitis in children, particularly in cases where ultrasound is equivocal or nondiagnostic, as an alternative to CT. Ultrafast MRI requires no sedation and no oral or IV contrast agent and has no associated radiation exposure risks.

The effect of abdominal pain duration on the accuracy of diagnostic imaging for pediatric appendicitis

STUDY OBJECTIVE

Advanced imaging with computed tomography (CT) or ultrasonography is frequently used to evaluate for appendicitis. The duration of the abdominal pain may be related to the stage of disease and therefore the interpretability of radiologic studies. Here, we investigate the influence of the duration of pain on the diagnostic accuracy of advanced imaging in children being evaluated for acute appendicitis.

METHODS

A secondary analysis of a prospective multicenter observational cohort of children aged 3 to 18 years with suspected appendicitis who underwent CT or ultrasonography was studied. Outcome was based on histopathology or telephone follow-up. Treating physicians recorded the duration of pain. Imaging was coded as positive, negative, or equivocal according to an attending radiologist's interpretation.

RESULTS

A total of 1,810 children were analyzed (49% boys, mean age 10.9 years [SD 3.8 years]); 1,216 (68%) were assessed by CT and 832 (46%) by ultrasonography (238 [13%] had both). The sensitivity of ultrasonography increased linearly with increasing pain duration (test for trend: odds ratio=1.39; 95% confidence interval 1.14 to 1.71). There was no association between the sensitivity of CT or specificity of either modality with pain duration. The proportion of equivocal CT readings significantly decreased with increasing pain duration (test for trend: odds ratio=0.76; 95% confidence interval 0.65 to 0.90).

CONCLUSION

The sensitivity of ultrasonography for appendicitis improves with a longer duration of abdominal pain, whereas CT demonstrated high sensitivity regardless of pain duration. Additionally, CT results (but not ultrasonographic results) were less likely to be equivocal with longer duration of abdominal pain.

Computerized Tomography in the Workup of Pediatric Appendicitis: Why are Children Scanned?

Physicians increasingly use computerized tomography (CT) for the evaluation of suspected acute appendicitis (AA) in children despite increasing awareness of the potential dangers of CT-associated radiation exposure. Many studies demonstrate the value of CT in the diagnosis of AA, but none have determined what factors influence the decision to perform a CT. We investigated factors associated with the use of CT during initial workup of children who subsequently underwent appendectomy. This is a retrospective review of all patients aged 0 to 17 years who underwent appendectomy for AA by pediatric surgeons over 11 years. Both univariate and multivariable logistic regression models were created to predict use of CT. A total of 546 children underwent appendectomy for AA, of which 293 (53%) underwent CT. In univariate analysis, seven variables were significantly associated with the use of CT: female gender, Hispanic ethnicity, initial presentation to referring hospitals, lower Alvarado scores, delays from onset of symptoms to hospital presentation, migration, and rebound tenderness. In multivariable analysis, four variables significantly independently predicted the use of CT: initial presentation to a referring hospital [odds ratio (OR) 3.50), female gender (OR 1.49), increased latency from symptom onset to presentation (OR 1.34), and the presence of rebound tenderness (OR 0.23), which had a protective effect; the overall model was statistically significant ( P < 0.0001). This model is the first to define variables that significantly predict CT utilization in the pediatric population. Continued investigation will be necessary to develop effective algorithms for judicious use of CT for suspected AA.

The Alvarado score for predicting acute appendicitis: a systematic review

BACKGROUND

The Alvarado score can be used to stratify patients with symptoms of suspected appendicitis; the validity of the score in certain patient groups and at different cut points is still unclear. The aim of this study was to assess the discrimination (diagnostic accuracy) and calibration performance of the Alvarado score.

METHODS

A systematic search of validation studies in Medline, Embase, DARE and The Cochrane library was performed up to April 2011. We assessed the diagnostic accuracy of the score at the two cut-off points: score of 5 (1 to 4 vs. 5 to 10) and score of 7 (1 to 6 vs. 7 to 10). Calibration was analysed across low (1 to 4), intermediate (5 to 6) and high (7 to 10) risk strata. The analysis focused on three sub-groups: men, women and children.

RESULTS

Forty-two studies were included in the review. In terms of diagnostic accuracy, the cut-point of 5 was good at 'ruling out' admission for appendicitis (sensitivity 99% overall, 96% men, 99% woman, 99% children). At the cut-point of 7, recommended for 'ruling in' appendicitis and progression to surgery, the score performed poorly in each subgroup (specificity overall 81%, men 57%, woman 73%, children 76%). The Alvarado score is well calibrated in men across all risk strata (low RR 1.06, 95% CI 0.87 to 1.28; intermediate 1.09, 0.86 to 1.37 and high 1.02, 0.97 to 1.08). The score over-predicts the probability of appendicitis in children in the intermediate and high risk groups and in women across all risk strata.

CONCLUSIONS

The Alvarado score is a useful diagnostic 'rule out' score at a cut point of 5 for all patient groups. The score is well calibrated in men, inconsistent in children and over-predicts the probability of appendicitis in women across all strata of risk.

Ultrasonography aids decision-making in children with abdominal pain

INTRODUCTION

Although regular clinical assessment of the acute abdomen is considered best practice, ultrasonography confirming the presence of appendicitis will add to the decision-making process. The aim of this study was to assess the accuracy of ultrasonography and its usefulness in diagnosing acute appendicitis in a regional paediatric surgical institution.

METHODS

Retrospectively and in this order, radiology, theatre and histopathology databases were searched for patients who had presented with acute abdominal pain, patients who had undergone an appendicectomy and all appendix specimens over a two-year period. The databases were cross-referenced against each other.

RESULTS

A total of 273 non-incidental appendicectomies were performed over the study period. The negative appendicectomy rate was 16.5% and the perforation rate 23.7%. Thirty-nine per cent of children undergoing an appendicectomy had at least one pre-operative ultrasound scan. Ultrasonography as a diagnostic tool for acute appendicitis in children had a sensitivity of 83.3%, a specificity of 97.4%, a positive predictive value of 92.1% and a negative predictive value of 94.0%.

CONCLUSIONS

Ultrasonography is used liberally to aid in the decision making process of equivocal and complicated cases of acute appendicitis and it achieves good measures of accuracy. As a diagnostic tool it is unique in its ability to positively predict as well as exclude. A high negative predictive value suggests that more patients could be managed on an outpatient basis following a negative scan.

The impact of early sonographic evaluation on hospital admissions of children with suspected acute appendicitis

PURPOSE

Early ultrasound (US) evaluation of children with abdominal pain and suspected acute appendicitis (AA) is an important diagnostic tool. Since 2007, US has become part of routine emergency room (ER) work-up performed for suspected pediatric AA in our hospital.

METHODS

We retrospectively compared hospital admissions from 2007 to 2008 with those from 2005 to 2006, when most ultrasounds were done after admission to Pediatric Surgery for observation.

RESULTS

During the study (2005-2008), 6,511 children came to the ER with acute abdominal pain. Although pediatric ER sonography increased from 28.1% (865/3,079) in 2005-2006 to 51.7% (1,775/3,432) in 2007-2008 (p < 0.0001), hospitalizations decreased from 33 to 30.1% (p = 0.011). Concurrently, ER US for AA increased from 20.8% (639/2,440) to 38.9% (1,336/2,096) (p < 0.0001), admissions for suspected AA decreased from 51.8% (331/639) to 42% (561/1,336) (p < 0.0001).

CONCLUSIONS

Sonography led to a significant decline in admissions and better selection of patients who required surgery for AA. Recurrent ER referrals for the same complaint within 2 weeks was very low (2.9%) with no difference between the two study periods (p = 1); none had AA. These findings encourage us to continue early US in children with suspected AA. This effective tool decreases unnecessary hospital stays, investigative procedures, and surgery, while reducing costs.

The influence of body mass index on the accuracy of ultrasound and computed tomography in diagnosing appendicitis in children

BACKGROUND

Appendicitis is a common pediatric surgical diagnosis that is often guided by radiographic imaging such as ultrasound (US) or computed tomography (CT). Whereas US is preferred because it avoids radiation, data suggest it is less sensitive than CT in diagnosing appendicitis. Body habitus, characterized by body mass index (BMI), may affect the diagnostic value of advanced radiological imaging in children with abdominal pain.

OBJECTIVE

The aim of the study was to determine the relationship between BMI and accuracy of US and CT scan for suspected appendicitis.

METHODS

We conducted a prospective, observational study of children with suspected appendicitis who presented to the emergency department and underwent radiographic evaluation from June 2007 to July 2008. Patient height and weight were obtained to calculate BMI and correlating z score, zBMI. Patients were grouped into standardized categories: underweight/normal weight, overweight, and obese based on zBMI. Emergency physicians ordered imaging as guided by standard clinical management. Pediatric attending radiologists evaluated all imaging studies; final radiology reports were reviewed and coded by 2 independent reviewers. Appendicitis was defined by pathology. Statistical analysis was performed to evaluate test performance of US and CT in diagnosing appendicitis as related to BMI.

RESULTS

Over the study period, 176 patients with suspected appendicitis underwent US and/or CT. Mean age was 11.8 ± 4.2 years; 42% were male. zBMI ranged from -2.78 to 2.75 (mean, 0.59); 70 children (40%) were overweight or obese; 73 (42%) had appendicitis. Ultrasound was performed on 147 (84%), and CT on 128 children (73%); 99 children (56%) had both studies. The overall sensitivity for US in diagnosing appendicitis was 38% (95% confidence interval [CI], 26%-52%) with a specificity of 97% (95% CI, 90%-99%). In the underweight/normal weight group, the sensitivity of US was 45% (95% CI, 27%-64%); in the overweight group, 35% (95% CI, 15%-61%), and in the obese group, 22% (95% CI, 4%-60%). The sensitivity and specificity of CT were 96% (95% CI, 86%-99%) and 97% (95% CI, 90%-100%) and did not vary by zBMI class.

CONCLUSIONS

The sensitivity and specificity of CT for appendicitis are excellent regardless of BMI. Despite a trend of decreasing sensitivity with increasing BMI when using US, no statistically significant difference was found, likely because of type II error.

Computerized Tomography Utilization in Children with Appendicitis—Differences in Referring and Children's Hospitals

Increasingly, physicians rely on computerized tomography (CT) to aid in the workup of acute appendicitis (AA) in children despite the potential negative effects of CT-associated radiation exposure. Few studies have investigated the context or location in which the decision to perform CT for AA is made. We sought to determine where the decision to use CT was made during the initial workup of pediatric patients who later underwent an appendectomy. We reviewed the medical record of all patients at a children's hospital (CH) receiving appendectomy over 10.5 years. We abstracted clinical variables using an established clinical AA scoring system, demographics and outcome variables. Patients who underwent CT were compared with those who did not. Additionally, we identified the location where the CT was performed. Our children's hospital was compared with referring hospitals (RHs) with regard to utilization of CT imaging. Five hundred and forty-six patients underwent appendectomy for AA at CH. Of these, 50 per cent underwent CT. Patients who initially presented at the RHs underwent CT at a significantly higher rate than those first presenting to CH ( P < 0.0001). Moreover, we found that unlike at the RHs, patients with a higher AA score underwent CT at CH less often ( P < 0.0002). RHs used CT more often than CH to diagnose AA in our cohort. CH avoided CT for patients with higher Alvarado scores. Further research is needed to elucidate factors that lead healthcare providers to use CT for children with suspected AA to eliminate unnecessary CT-associated radiation exposure.

Ultrasonography aids decision-making in children with abdominal pain

INTRODUCTION

Although regular clinical assessment of the acute abdomen is considered best practice, ultrasonography confirming the presence of appendicitis will add to the decision-making process. The aim of this study was to assess the accuracy of ultrasonography and its usefulness in diagnosing acute appendicitis in a regional paediatric surgical institution.

METHODS

Retrospectively and in this order, radiology, theatre and histopathology databases were searched for patients who had presented with acute abdominal pain, patients who had undergone an appendicectomy and all appendix specimens over a two-year period. The databases were cross-referenced against each other.

RESULTS

A total of 273 non-incidental appendicectomies were performed over the study period. The negative appendicectomy rate was 16.5% and the perforation rate 23.7%. Thirty-nine per cent of children undergoing an appendicectomy had at least one pre-operative ultrasound scan. Ultrasonography as a diagnostic tool for acute appendicitis in children had a sensitivity of 83.3%, a specificity of 97.4%, a positive predictive value of 92.1% and a negative predictive value of 94.0%.

CONCLUSIONS

Ultrasonography is used liberally to aid in the decision making process of equivocal and complicated cases of acute appendicitis and it achieves good measures of accuracy. As a diagnostic tool it is unique in its ability to positively predict as well as exclude. A high negative predictive value suggests that more patients could be managed on an outpatient basis following a negative scan.

Surgeon-performed ultrasound as a diagnostic tool in appendicitis

PURPOSE

Diagnosing appendicitis may require adjunct studies such as computed tomography or ultrasound (US). Combining a clinical examination with surgeon-performed US (SPUS) may increase diagnostic accuracy and decrease radiation exposure and costs.

METHODS

A prospective study was conducted including children with a potential diagnosis of appendicitis. A surgery resident performed a clinical examination and US to make a diagnosis. Final diagnosis of appendicitis was confirmed by operative findings and pathology. Results were compared with radiology department US (RDUS) and a large randomized trial. Analysis was performed using Fisher exact test.

RESULTS

Fifty-four patients were evaluated and underwent SPUS. Twenty-nine patients (54%) had appendicitis. Overall accuracy was 89%, with accuracy increasing from 85% to 93% between the 2 halves of the study. Radiology department US was performed on 21 patients before surgical evaluation, yielding an accuracy of 81%. Surgeon-performed US on those 21 patients yielded an accuracy of 90%. No statistical differences were found between any groups (P > .05).

CONCLUSION

Accuracy of SPUS was similar to RDUS and that of a large prospective randomized trial performed by radiologists. Furthermore, when the same clinician performs the clinical examination and US, a high level of accuracy can be achieved. With this degree of accuracy, SPUS may be used as a primary diagnostic tool and computed tomography reserved for challenging cases, limiting costs, and radiation exposure.

Effectiveness of a staged US and CT protocol for the diagnosis of pediatric appendicitis: reducing radiation exposure in the age of ALARA

PURPOSE

To evaluate the effectiveness of a staged ultrasonography (US) and computed tomography (CT) imaging protocol for the accurate diagnosis of suspected appendicitis in children and the opportunity for reducing the number of CT examinations and associated radiation exposure.

MATERIALS AND METHODS

This retrospective study was compliant with HIPAA, and a waiver of informed consent was approved by the institutional review board. This study is a review of all imaging studies obtained in children suspected of having appendicitis between 2003 and 2008 at a suburban pediatric emergency department. A multidisciplinary staged US and CT imaging protocol for the diagnosis of appendicitis was implemented in 2003. In the staged protocol, US was performed first in patients suspected of having appendicitis; follow-up CT was recommended when US findings were equivocal. Of 1228 pediatric patients who presented to the emergency department for suspected appendicitis, 631 (287 boys, 344 girls; age range, 2 months to 18 years; median age, 10 years) were compliant with the imaging pathway. The sensitivity, specificity, negative appendectomy rate (number of appendectomies with normal pathologic findings divided by the number of surgeries performed for suspected appendicitis), missed appendicitis rate, and number of CT examinations avoided by using the staged protocol were analyzed.

RESULTS

The sensitivity and specificity of the staged protocol were 98.6% and 90.6%, respectively. The negative appendectomy rate was 8.1% (19 of 235 patients), and the missed appendicitis rate was less than 0.5% (one of 631 patients). CT was avoided in 333 of the 631 patients (53%) in whom the protocol was followed and in whom the US findings were definitive.

CONCLUSION

A staged US and CT imaging protocol in which US is performed first in children suspected of having acute appendicitis is highly accurate and offers the opportunity to substantially reduce radiation.

Typical signs of acute appendicitis in ultrasonography mimicked by other diseases?

BACKGROUND

The diagnosis of acute appendicitis in pediatric patients is difficult. There are patients with positive ultrasonography without clinical or histological confirmation of acute appendicitis. It is essential to recognise these patients to avoid unnecessary surgery.

METHODS

During 1 year, we compared the patients with 'false-positive' ultrasonography with those with 'true-positive' and those with 'true-negative' ultrasonography.

RESULTS

Eighty-two patients were admitted to our inpatient ward for suspected appendicitis. Ultrasonography was performed on 68 patients. In sixteen cases, the ultrasonography showed typical signs of acute appendicitis though the patients turned out to be negative for acute appendicitis either by an observation period (n = 13) or by negative histology (n = 3). We could not find any significant differences between the groups in terms of age, gender or laboratory inflammation markers, though the latter tended to be elevated in patients with confirmed appendicitis.

CONCLUSIONS

There are patients with clearly visible typical signs of acute appendicitis that do not need surgery and cannot be distinguished from others by age, gender or laboratory values. In conclusion, the clinical presentation still is the determining indicator for need of surgery. The underlying cause of the visible changes of the appendiceal area remains unclear, but there are several presumptions.

Management of acute appendicitis: an imaging strategy in children

The pre-operative diagnosis of acute appendicitis (AA) has markedly changed during the last couple of decades due to the advent of modern imaging technology. Nowadays, the use of imaging has dramatically changed the way we approach children admitted to emergency room for abdominal pain with suspected AA. This change is mainly manifested in our diagnostic strategy.

US examination of the appendix in children with suspected appendicitis: the additional value of secondary signs

This study evaluated the additional value of secondary signs in the diagnosing of appendicitis in children with ultrasound. From May 2005 to June 2006, 212 consecutive paediatric patients with suspected appendicitis were examined. Ultrasonographic depiction of the appendix was classified into four groups: 1, normal appendix; 2, appendix not depicted, no secondary signs of appendicitis; 3, appendix not depicted with one of the following secondary signs: hyperechoic mesenteric fat, fluid collection, local dilated small bowel loop; 4, depiction of inflamed appendix. We classified 96 patients in group 1, 41 in group 2, 13 in group 3, and 62 in group 4. Prevalence of appendicitis was 71/212 (34%). Negative predictive values of groups 1 and 2 were 99% and 100%, respectively. Positive predictive values of groups 3 and 4 were 85% and 95%, respectively. In groups 3 and 4, hyperechoic mesenteric fat was seen in 73/75 (97.3%), fluid collections and dilated bowel loops were seen in 12/75 (16.0%) and 5/75 (6.6%), respectively. This study shows that in case of non-visualization of the appendix without secondary signs, appendicitis can be safely ruled out. Furthermore, secondary signs of appendicitis alone are a strong indicator of acute appendicitis.

Prospective evaluation of emergency physician performed bedside ultrasound to detect acute appendicitis

OBJECTIVES

To evaluate the accuracy of emergency physicians using bedside ultrasound to detect appendicitis (BUSA).

METHODS

Patients presenting to the emergency department with a clinical suspicion of appendicitis were prospectively enrolled and received a 5-min BUSA. Patients received routine work-up for acute appendicitis as deemed appropriate by the attending physician. Radiologists and consulting surgeons were blinded to BUSA results. The criterion standard for the presence or absence of acute appendicitis was the pathology report for patients who received appendectomies, and telephone follow-up for patients discharged home without surgical intervention.

RESULTS

A total of 132 patients were enrolled. In 44 cases BUSA was positive. Of these, 37 had surgical pathology reports consistent with acute appendicitis, whereas seven did not have appendicitis. In 82 cases, BUSA was negative. Of these, 62 were determined not to have appendicitis, whereas 20 had appendicitis by pathology. Sensitivity for BUSA was 65% [95% confidence interval (CI) 52-76], specificity was 90% (95% CI 81-95), positive predictive value was 84% (95% CI 71-92), and negative predictive value was 76% (95% CI 65-84). The likelihood ratio of a positive BUSA was 6.4 (95% CI 3.1-13.2). Five patients discharged home with a diagnosis other than appendicitis were unable to be reached by telephone, and were excluded from data analysis.

CONCLUSION

Our study gives insufficient evidence to support the use of bedside ultrasound by emergency physicians to rule out appendicitis. The high specificity in our study, however, suggests that with further training, BUSA may be useful to rule-in appendicitis in some patients.

The role of imaging in children with suspected appendicitis: the UK perspective

The diagnosis of uncomplicated acute appendicitis is often straightforward, allowing timely appendicectomy without the need for expensive tests or imaging. Repeated clinical examination by an experienced surgeon has traditionally been the key to making the diagnosis in both straightforward and difficult cases. Nonetheless, all surgeons will remove some normal appendices. Sometimes it can be particularly difficult to make the diagnosis, especially in the child under 5 years of age, in teenage girls, in young women and in the elderly. When difficult to make, the diagnosis may be significantly delayed and since the pathology is progressive, the patient may suffer potentially avoidable complications. This paper looks at two potential roles for imaging. Firstly, can imaging, applied selectively, help make the difficult diagnosis less difficult and so reduce delays and morbidity? Secondly, could imaging all patients with suspected appendicitis reduce the number of normal appendices removed from children who seem to have all the signs and symptoms of straightforward uncomplicated acute appendicitis but who actually have presumed self-resolving non-appendiceal pathology? The answer to these questions may depend on three factors that are not entirely independent: a surgical unit's current audited negative appendicectomy rate, population base/case mix and the expertise of the examining surgeon. Individual surgeons and some surgical units, by policy, use modern imaging techniques with quite different frequencies that may be appropriate depending on these three factors. This article argues that a careful history and repeated clinical examination is the key to making the diagnosis, with imaging, primarily ultrasonography, being used in patients with a palpable mass or in those having had 48 h of hospital observation without progress. In Europe, imaging has played a limited role in the investigation of the child with suspected appendicitis with the diagnosis relying on repeated examination by an experienced clinician. Ongoing changes in surgical training in the UK may affect the acquisition of clinical expertise that is crucial to this clinical management. High-quality surgical training and surgical audit are needed to monitor the delivery of care and to ensure that the care pathway being used is appropriate for the local resources and population.

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.