Acute appendicitis: investigating an optimal outer appendiceal diameter cut-point in a pediatric population

Comparison of ultrasound assisted and intraoperative diameter measurement in acute appendicitis

Detailed anamnesis and systematic physical examination are often relevant in the diagnostic routine of acute appendicitis. However, physicians are increasingly motivated to obtain radiological approval. Inherent limitations due to radiologists' experience and the presenting anatomy may result in contradictory outcomes between the described and intraoperative findings. In this study, a comparison of anthropometric measurements of the appendix vermiformis obtained by radiologists and surgeons in children with acute appendicitis is discussed. The external appendiceal diameter in 53 patients who underwent surgery between April 2022 and January 2024 was measured at three different anatomical locations during preoperative ultrasound and intraoperatively with the help of Vernier calipers. Appendectomy materials were classified into negative, acute, and complicated appendicitis subgroups on the basis of histopathological results. The widest median diameter, expressed in millimeters, was analyzed statistically in terms of diagnostic accuracy. Histopathological analysis revealed negative appendectomy in 15.1%, acute appendicitis in 66%, and complicated appendicitis in 18.8% of the patients. The median age at presentation was 11.4 years (4-17.3 years), and 45.3% of the patients were females. The average median appendiceal diameter was 7.8 ± 2.4 mm according to the caliper and 7.9 ± 2.7 mm according to ultrasound (p > 0.05). The evaluation by the caliper revealed a much smaller diameter in 19 patients than did ultrasound. The appendiceal diameter of eight documented negative appendectomy samples was 7 mm or greater. US failed to identify the presence of an appendicolith in 11 cases (20.8%), all of which were disclosed during histopathological evaluation. It is possible to conclude that ultrasound and intraoperative anthropometric measurements correlate according to our study. Diagnostic accuracy, however, which is individually based on ultrasound appendix diameter values greater than 6 mm, is controversial. It is clear that comparison and further reinterpretation of such anthropometric measurements in light of histopathological consequences may help diminish the frequency of negative and perforated appendectomies.

Identification of children with a nondiagnostic ultrasound at a low appendicitis risk using a pediatric Appendicitis Risk Calculator

OBJECTIVES

Up to 50% of ultrasounds (USs) for suspected pediatric appendicitis are nondiagnostic. While the validated low-risk clinical pediatric Appendicitis Risk Calculator (pARC) score < 15% and the low-risk US with nonvisualized appendix and no periappendiceal inflammation carry relatively low appendicitis risks, the contribution of the combination of both characteristics to this risk has never been assessed. The primary objective was to determine the proportion of children with the low-risk US-low-risk pARC combination with appendicitis. We hypothesized that this proportion would be 2.5% (upper 95% CI ≤ 5%).

METHODS

A retrospective cohort study of 448 previously healthy children 4-17 years old at a pediatric ED with suspected appendicitis, nondiagnostic US, and persistent clinical concern about appendicitis. Two investigators abstracted demographic, clinical, and imaging data. Based on published criteria, USs were classified as low-risk or high-risk. The pARC includes seven demographic, clinical, and laboratory variables and is quantified according to the published formula. The primary outcome was appendicitis, based on the histological evidence. All nonoperated patients underwent a 1-month-follow-up to exclude delayed appendicitis diagnoses.

RESULTS

Sixty of the 448 (13.4%) patients had appendicitis; 269 (60%) had low-risk US, 262 (58.4%) had low-risk pARC, and 163 (36.4%) had both characteristics. The appendicitis rates with low-risk pARC alone and low-risk US alone were 14/262 (5.4%) and 21/269 (7.8%), respectively. A total of 2/163 children (1.2%) with low-risk pARC and low-risk US had appendicitis (95% CI 0%-4.4%). Higher-risk US increased the appendicitis odds 5 (95% CI 1.54-20.55) to 11 times (95% CI 2.41-51.10) across pARC levels. The low-risk combination had sensitivity of 96.7% (95% CI 88.5%-99.6%), specificity of 41.5%, positive predictive value of 20.4%, and negative predictive value of 98.8% (95% CI 95.6%-99.9%).

CONCLUSIONS

The children with low-risk pARC and low-risk US combination are unlikely to have appendicitis and can be discharged home. The presence of higher-risk US-pARC score combinations substantially increases the appendicitis risk and warrants reassessment or interval imaging.

Characterization and quantification of fluid in the abdomen by ultrasound and magnetic resonance imaging in children with clinical suspicion of appendicitis

PURPOSE

While regarded as a secondary sign of pediatric appendicitis, the frequency of physiologic intra-abdominal fluid in children with suspected but absent appendicitis is unknown. Ex vivo: to assess the validity of US/MRI measurements of free fluid. In vivo: in suspected pediatric appendicitis, to assess the amount of abdominal fluid by US and MRI, determine performance characteristics of US in fluid detection and identify fluid volume ranges in confirmed appendicitis.

METHODS

Ex vivo: criterion validity of US and MRI for fluid volume measurements was tested using tissue-mimicking phantoms filled with different volumes of distilled water. In vivo: all participants from a previous prospective study of suspected appendicitis were evaluated by US; MRI was performed after equivocal USs. Qualitative and quantitative analyses of abdominal fluid and correlation of fluid presence with appendicitis were performed.

RESULTS

Ex vivo: no difference was found between phantom-fluid amount and measured volume using the formula for volume of an ellipsoid for US (P=0.19) or MRI (P=0.08). In vivo: intra-abdominal fluid was present in 212/591 (35.9%) patients; 75/212 patients with fluid (35.4%) had appendicitis, 60 (28.3%) had alternate diagnoses, and 77 (36.3%) had physiologic fluid. Sensitivity and specificity of US for fluid detection were 84% (95% CI 71-93) and 65% (95% CI 52-77), respectively. In children with versus without appendicitis, the respective ranges of fluid volume were 0.7-1148.8 ml and 0.8-318 ml.

CONCLUSION

The volume of an ellipsoid formula is a valid method for quantifying intra-abdominal fluid. The sole presence of intra-abdominal fluid on US does not support the diagnosis of pediatric appendicitis.

Properties of ultrasound-rapid MRI clinical diagnostic pathway in suspected pediatric appendicitis-A prospective cohort study

OBJECTIVE

to determine diagnostic accuracy of an US-MRI clinical diagnostic pathway to detect appendicitis in the emergency department (ED).

STUDY DESIGN

prospective cohort study of 624 previously healthy children 4-17 years old undergoing US for suspected appendicitis and clinical re-assessment. Children with non-diagnostic USs and persistent appendicitis concern/conclusive US-reassessment discrepancies underwent ultra-rapid MRI (US-MRI pathway), interpreted as positive, negative or non-diagnostic. Cases with missed appendicitis, negative appendectomies, and CT utilization were considered clinically diagnostically inaccurate. Primary outcome was the proportion of accurate diagnoses of appendicitis/lack thereof by the pathway.

RESULTS

150/624 (24%) children had appendicitis;255 USs (40.9%) were non-diagnostic. Of 139 US-MRI pathway children (after 117 non-diagnostic and 22 conclusive USs), 137 [98.6%; 95% CI 0.96-1.00] had clinically accurate outcomes (1 CT, 1 negative appendectomy): sensitivity 18/18 [100%], specificity 119/121 [98.3%], positive predictive value 18/20 [90.5%], negative predictive value 119/119 [100%]. MRI imaging accuracy was 134/139 (96.4%); 3 MRIs were non-diagnostic (no appendicitis). In the overall algorithm, 616/624 [98.7% (0.97-0.99)] patients had accurate outcomes: 147/150 (98.0%) appendicitis cases had confirmatory surgeries (3 CTs) and 469/474 (98.9%) appendicitis-negative children had no surgery/CT.

CONCLUSION

this study demonstrated high clinical accuracy of the US-rapid-MRI pathway in suspected pediatric appendicitis after non-diagnostic US.

The utility of sonographic signs to diagnose simple and complicated appendicitis in children

BACKGROUND

Acute appendicitis is classified into simple (SA) and complicated (CA). Ultrasound scans (USS) can be useful in clinically equivocal cases, by visualising primary and secondary signs. This study explores the utility of sonographic signs to diagnose and differentiate appendicitis in children.

METHODS

Single-centre retrospective cohort study over a 2-year period. Consecutive USS for suspected appendicitis were included; sonographic signs were extracted from standardised institutional worksheets. USS results were compared with pre-defined intraoperative criteria for SA and CA, confirmed with histological analysis. Data are reported as median [interquartile range], percentages (number), area under the curve (AUC), conventional diagnostic formulae and adjusted odds ratios following multiple logistic regression (p < 0.05 considered significant).

RESULTS

A total of 934 USS were included, with median age 10.7 [8.0-13.4] years, majority were female (54%). One quarter (n = 226) had SA, 12% (n = 113) had CA, 61% (n = 571) had no appendectomy and 3% (n = 24) had negative appendicectomy. Appendix visualisation rate on USS was 61% (n = 569), with 62% (n = 580) having a conclusive report. Sonographic signs suggesting appendicitis included an appendiceal diameter > 7 mm (AUC 0.92, [95% CI: 0.90-0.94]), an appendicolith (p = 0.003), hyperaemia (p = 0.001), non-compressibility (p = 0.029) and no luminal gas (p = 0.004). Secondary sonographic signs included probe tenderness (p < 0.001) and peri-appendiceal echogenic fat (p < 0.001). Sonographic signs suggesting CA over SA comprised a diameter > 10.1 mm (AUC 0.63, [95% CI: 0.57-0.69]), an appendicolith (p = 0.003) and peri-appendiceal fluid (p = 0.004).

CONCLUSION

Presence of specific sonographic signs can aid diagnosis and differentiation of simple and complicated appendicitis in children.

Ultrasonographic evaluation of cecal appendix diameter in pediatric population

Objective

To stratify ultrasound samples in a pediatric population undergoing evaluation for acute appendicitis to examine the variability in cecal appendix diameter, in different age groups, and to determine whether there is a prevalent value for each age group.

Methods

A retrospective cross-sectional study with 196 children aged 0 to 15 years. Data were extracted from reports of ultrasound examinations carried out between 2008 and 2015. Children with sonographic diagnosis of appendicitis or other signs of periappendiceal inflammation were excluded.

Results

The evaluation of the anteroposterior measurement of the cecal appendix revealed a mean diameter of 4.14mm (standard deviation: 0.93mm; 95%CI: 3.86-4.14). Cecal appendix diameter did not differ significant between age groups.

Conclusion

Evaluation of the anteroposterior diameter of the cecal appendix in centimeters in a sample of 196 children aged 0 to15 years revealed a mean diameter of 4.14mm (standard deviation, 0.93mm. There were no significant differences in cecal appendix diameter following stratification by age. Results indicate a single value can be adopted for mean cecal appendix diameter in pediatric populations.

Revisiting the Appendiceal Diameter via Ultrasound for the Diagnosis of Acute Appendicitis

OBJECTIVES

This study aims to investigate the optimal outer appendiceal diameter via ultrasound for the diagnosis of acute appendicitis.

METHODS

A retrospective chart review was conducted on patients (ages, 2-18 years) presenting to an urban pediatric emergency department between January 1, 2009 and December 31, 2010 with suspected acute appendicitis. Children were considered as having "suspected acute appendicitis" if they (1) presented with acute abdominal pain and had either a surgical consult or an abdominal ultrasound, or (2) presented or transferred with the stated suspicion of acute appendicitis. Pathology reports were used to confirm the diagnosis of appendicitis. The appendiceal diameters were determined by board-certified pediatric radiologists.

RESULTS

A total of 320 patient charts were reviewed (females, 57%; mean age, 10.9; SD, 3.9). Seventy-two percent (N = 230) of the patients screened positive for acute appendicitis via ultrasound, 69% (N = 222) had confirmed acute appendicitis, 75% (N = 239) of the ultrasound reports included an outer appendiceal diameter. Overall, ultrasound was found to be highly sensitive (91%) and moderately specific (74%). With an outer appendiceal diameter of 6 mm as a cutoff, ultrasound had an excellent sensitivity (100%) but poor specificity (43%). With an outer diameter of 7 mm as a cutoff, sensitivity decreased to 94% but specificity increased to 71%. With increasing cutoff size, the sensitivity decreased and specificity increased.

CONCLUSIONS

Our data suggest that the optimal outer appendiceal diameter for the diagnosis of acute appendicitis should be 7 mm instead of the currently used 6 mm.

Diagnostic accuracy of surgeon performed ultrasound (SPU) for appendicitis in children

AIM

Compare the diagnostic accuracy of surgeon performed ultrasound to radiology performed ultrasound in children presenting with suspected appendicitis to a tertiary care pediatric hospital in Australia.

METHODS

Children under 16 presenting to the emergency department of The Children's Hospital at Westmead were considered for the study. Patients with obvious signs of appendicitis not requiring ultrasound and those with established ultrasound diagnosis of appendicitis were excluded. Ultrasound was performed by a Pediatric Surgeon (SPU) after obtaining consent. The treating team was blinded to the results. Patient underwent formal ultrasound in radiology (RPU) and treatment was based on the formal report. SPU result was reviewed by a radiologist blinded to results of RPU. The results were compared.

RESULTS

65 children underwent ultrasound. 35 were male. Median age was 10 (range3-15). Median weight was 36 kg (range 12.6-76.2 kg), z-score median 0.21 (-1.83 to 2.74). Symptom duration ranged from few hours to 2 weeks but majority (45) had symptoms for less than 48 h. Prevalence of appendicitis was 45%. Thirty two underwent surgery. Negative appendicectomy rate was 9.4%. Thirty three did not have surgery. 8 represented but only one proceeded to appendicectomy. SPU was done earlier than RPU (median 12 h vs 14.15 h) p = 0.088. Diagnostic accuracy using ROC did not reveal significant difference.

CONCLUSION

SPU can be performed earlier than RPU with reliable accuracy. Training surgical trainees will enable early diagnosis and management of appendicitis.

Diagnostic Performance of Ultrasonography for Pediatric Appendicitis: A Night and Day Difference?

RATIONALE AND OBJECTIVES

For imaging pediatric appendicitis, ultrasonography (US) is preferred because of its lack of ionizing radiation, but is limited by operator dependence. This study investigates the US diagnostic performance during night shifts covered by radiology trainees compared to day shifts covered by attending radiologists.

MATERIALS AND METHODS

Appy-Scores (1 = completely visualized normal appendix; 2 = partially visualized normal appendix; 3 = nonvisualized appendix with no inflammatory changes in the expected region of the appendix; 4 = equivocal; 5a = nonperforated appendicitis; 5b = perforated appendicitis) from 2935 US examinations (2161:774, day-to-night) from July 2013 to 2014 were correlated with the intraoperative diagnoses and the clinical follow-up. The diagnostic performance of trainees and attendings was compared with Fisher exact test. Interobserver agreement was measured by Cohen kappa coefficient.

RESULTS

Appendicitis prevalence was 25.3% (day) and 22.5% (night). Sensitivity, specificity, accuracy, negative predictive value, and positive predictive vale were 94.0%, 93.7%, 93.8%, 97.9%, and 83.4% during the day and 92.0%, 91.2%, 91.3%, 97.5%, and 75.2% at night. Specificity (P = .048) and positive predictive value (P = .011) differed, with more false positives at night (7%) than during the day (4.7%). Trainee and attending agreement was high (k = 0.995), with Appy-Scores of 1, 4, and 5a most frequently discordant.

CONCLUSIONS

US has a high diagnostic performance and interobserver agreement for pediatric appendicitis when interpreted by radiology trainees during night shifts or attending radiologists during day shifts. However, lower specificity and positive predictive value at night warrants a thorough trainee education to avoid false-positive examinations.

Anatomic Reasons for Failure to Visualize the Appendix With Graded Compression Sonography: Insights From Contemporaneous CT

OBJECTIVE

The purpose of this study is to identify the anatomic locations of appendixes on CT when graded compression sonography fails to visualize the appendix.

MATERIALS AND METHODS

The study included 197 patients with suspected appendicitis whose appendixes were not visualized on graded compression sonography performed with typically used transducers of at least 10 MHz, who underwent CT within 48 hours following graded compression sonography, and who had available either pathologic examination following surgery or 6-week follow-up if surgery was not performed. Appendixes were retrospectively localized using four transverse quadrants (including the posteromedial quadrant) centered on the ileocecal valve and projected vertically, the craniocaudal level relative to the iliac crests, and the depth of the appendix as measured from the surface of the skin. Data were assessed using the Fisher exact test, t test, multinomial test, binomial distribution, ANOVA, and linear regression.

RESULTS

Appendixes were most frequently located in the posteromedial quadrant (123 of 197 patients [62.4%]; 95% CI, 55.3-69.2%) at a statistically significantly greater frequency than that expected by chance (p < 0.00001). Appendixes were located above the iliac crests in 19.8% of patients (39/197; 95% CI, 14.5-26.1%) and at depths exceeding the penetration of typical transducers of at least 10 MHz in 19.3% of patients (38/197; 95% CI, 14.0-25.5%). All appendixes (95% CI, 98.1-100.0%) were located within the range of 6-MHz transducers.

CONCLUSION

Appendixes that are not visualized on graded compression sonography are most frequently located in the posteromedial quadrant and are often located above the iliac crests or at depths too great for visualization with typically used transducers of at least 10 MHz. Accordingly, when the appendix is not visualized on graded compression sonography, targeted scanning of the posteromedial quadrant and the region above the iliac crests, and scanning with 6-MHz transducers, may enable visualization of the appendix and are recommended additions to scanning protocols.

Performance characteristics of magnetic resonance imaging without contrast agents or sedation in pediatric appendicitis

BACKGROUND

Magnetic resonance imaging (MRI) has emerged as a promising modality for evaluating pediatric appendicitis. However optimal imaging protocols, including roles of contrast agents and sedation, have not been established and diagnostic criteria have not been fully evaluated.

OBJECTIVE

To investigate performance characteristics of rapid MRI without contrast agents or sedation in the diagnosis of pediatric appendicitis.

MATERIALS AND METHODS

We included patients ages 4-18 years with suspicion of appendicitis who underwent rapid MRI between October 2013 and March 2015 without contrast agent or sedation. After two-radiologist review, we determined performance characteristics of individual diagnostic criteria and aggregate diagnostic criteria by comparing MRI results to clinical outcomes. We used receiver operating characteristic (ROC) curves to determine cut-points for appendiceal diameter and wall thickness for optimization of predictive power, and we calculated area under the curve (AUC) as a measure of test accuracy.

RESULTS

Ninety-eight MRI examinations were performed in 97 subjects. Overall, MRI had a 94% sensitivity, 95% specificity, 91% positive predictive value and 97% negative predictive value. Optimal cut-points for appendiceal diameter and wall thickness were ≥7 mm and ≥2 mm, respectively. Independently, those cut-points produced sensitivities of 91% and 84% and specificities of 84% and 43%. Presence of intraluminal fluid (30/33) or localized periappendiceal fluid (32/33) showed a significant association with acute appendicitis (P<0.01), with sensitivities of 91% and 97% and specificities of 60% and 50%. For examinations in which the appendix was not identified by one or both reviewers (23/98), the clinical outcome was negative.

CONCLUSION

Rapid MRI without contrast agents or sedation is accurate for diagnosis of pediatric appendicitis when multiple diagnostic criteria are considered in aggregate. Individual diagnostic criteria including optimized cut-points of ≥7 mm for diameter and ≥2 mm for wall thickness demonstrate high sensitivities but relatively low specificities. Nonvisualization of the appendix favors a negative diagnosis.

Spectral Doppler Waveforms for Diagnosis of Appendicitis: Potential Utility of Point Peak Systolic Velocity and Resistive Index Values

Purpose To test the hypothesis that appendiceal spectral Doppler waveforms can distinguish patients with and patients without appendicitis. Materials and Methods In this retrospective study, Doppler waveforms were obtained from intramural appendiceal arteries identified with color Doppler imaging in 60% (93 of 155) of consecutive patients whose appendices were visualized at graded compression ultrasonography (US) performed for suspected appendicitis (53 male and 40 female; age, 1-56 years; mean, 14.5 years) over the 5-month period from November 2015 through March 2016. Point, non-angle-corrected peak systolic velocity (PSV) and resistive index (RI) values were compared between patients with and patients without appendicitis by utilizing histopathologically proven appendicitis and 6-week clinical follow-up as diagnostic reference standards. Data were assessed by using the Student t test, exact binomial distribution, two-sample test of proportions, and receiver operating characteristic analysis. Results Among the 93 patients, 36 (38.7%) had proven appendicitis (mean PSV, 19.7 cm/sec; mean RI, 0.69) and 57 patients (61.2%) did not (mean PSV, 7.1 cm/sec, P < .0001; mean RI, 0.50, P < .0001). The area under the receiver operating characteristic curve for the diagnosis of appendicitis was 0.97 (95% confidence interval [CI]: 0.95, 1.00) for PSV and 0.86 (95% CI: 0.78, 0.95; P = .011) for RI. Chosen discriminatory criteria of PSV greater than 10 cm/sec and RI greater than 0.65 yielded specificity for appendicitis of 94.7% and 96.5% with sensitivity of 88.9% and 63.9% (P = .013) and negative predictive value of 93.1% and 80.9% (P = .045), respectively. Original clinical graded compression US interpretations based on established US findings demonstrated specificity of 96.2% and sensitivity of 100.0%. Considering the subset of 20 patients whose maximum outer diameter measured 6-8 mm, the discriminatory criteria of PSV greater than 10 cm/sec and RI greater than 0.65 yielded specificity for appendicitis of 88.9% each, with sensitivity of 100.0% and 63.6% and negative predictive value of 100.0% and 66.6%, respectively. Conclusion In patients with visualized appendices at US, those with appendicitis exhibit significantly higher point PSV and point RI values than do patients without appendicitis and are distinguishable with high specificity by using a PSV greater than 10 cm/sec and an RI greater than 0.65 as diagnostic criteria. ^© RSNA, 2017.

Sonographic Differentiation of Complicated From Uncomplicated Appendicitis: Implications for Antibiotics-First Therapy

OBJECTIVES

To evaluate sonographic findings as indicators of complicated versus uncomplicated appendicitis in the setting of known appendicitis, a necessary distinction in deciding whether to proceed with antibiotic therapy or with appendectomy.

METHODS

With Institutional Review Board approval and Health Insurance Portability and Accountability Act compliance, appendiceal sonograms of 119 patients with histopathologically proven appendicitis were retrospectively blindly reviewed to determine the presence or absence of the normally echogenic submucosal layer, the presence of mural hyperemia, periappendiceal fluid, appendicoliths, and hyperechoic periappendiceal fat and to determine the maximum outside diameter. Results were compared with the presence of complicated versus uncomplicated appendicitis on histopathologic examination and assessed by both univariate and mulitvariate logistic regression; confidence intervals (CIs) of proportions were assessed by the exact binomial test.

RESULTS

Thirty-two (26.9%) of the 119 patients had complicated appendicitis, including 11 with gangrenous appendicitis without perforation and 21 with gangrenous appendicitis and perforation. Loss of the submucosal layer was the only independent significant indicator of complicated appendicitis in multivariate regression (P < .001) and provided sensitivity and specificity values of 100.0% (95% CI, 89.1%-100.0%) and 92.0% (95% CI, 84.1%-96.7%), respectively.

CONCLUSIONS

Loss of the normally echogenic submucosal layer was the most useful sonographic finding for discriminating complicated from uncomplicated appendicitis, being the only finding independently and significantly associated with complicated appendicitis and, additionally, providing both high sensitivity and high specificity. This information may help a physician decide whether to proceed with antibiotic therapy or with appendectomy when treating a patient with appendicitis.

Size Matters: Point-of-Care Ultrasound in Pediatric Appendicitis

Ultrasound is the initial diagnostic modality of choice for evaluation of pediatric appendicitis. We report a case that highlights the importance of pain control, distraction, focusing on the appearance of the appendix and the surrounding structures, the value of size cutoff points for appendicitis, and repeating ultrasound examinations to optimize yield.

Development and validation of an ultrasound scoring system for children with suspected acute appendicitis

BACKGROUND

To facilitate consistent, reliable communication among providers, we developed a scoring system (Appy-Score) for reporting limited right lower quadrant ultrasound (US) exams performed for suspected pediatric appendicitis.

OBJECTIVE

The purpose of this study was to evaluate implementation of this scoring system and its ability to risk-stratify children with suspected appendicitis.

MATERIALS AND METHODS

In this HIPAA compliant, Institutional Review Board-approved study, the Appy-Score was applied retrospectively to all limited abdominal US exams ordered for suspected pediatric appendicitis through our emergency department during a 5-month pre-implementation period (Jan 1, 2013, to May 31, 2013), and Appy-Score use was tracked prospectively post-implementation (July 1, 2013, to Sept. 30,2013). Appy-Score strata were: 1 = normal completely visualized appendix; 2 = normal partially visualized appendix; 3 = non-visualized appendix, 4 = equivocal, 5a = non-perforated appendicitis and 5b = perforated appendicitis. Appy-Score use, frequency of appendicitis by Appy-Score stratum, and diagnostic performance measures of US exams were computed using operative and clinical finding as reference standards. Secondary outcome measures included rates of CT imaging following US exams and negative appendectomy rates.

RESULTS

We identified 1,235 patients in the pre-implementation and 686 patients in the post-implementation groups. Appy-Score use increased from 24% (37/155) in July to 89% (226/254) in September (P < 0.001). Appendicitis frequency by Appy-Score stratum post-implementation was: 1 = 0.5%, 2 = 0%, 3 = 9.5%, 4 = 44%, 5a = 92.3%, and 5b = 100%. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 96.3% (287/298), 93.9% (880/937), 83.4% (287/344), and 98.8% (880/891) pre-implementation and 93.0% (200/215), 92.6% (436/471), 85.1% (200/235), and 96.7% (436/451) post-implementation - only NPV was statistically different (P = 0.012). CT imaging after US decreased by 31% between pre- and post-implementation, 8.6% (106/1235) vs. 6.0% (41/686); P = 0.048). Negative appendectomy rates did not change (4.4% vs. 4.1%, P = 0.8).

CONCLUSION

A scoring system and structured template for reporting US exam results for suspected pediatric appendicitis was successfully adopted by a pediatric radiology department at a large tertiary children's hospital and stratifies risk for children based on their likelihood of appendicitis.

Predictive value of C-reactive protein, ultrasound and Alvarado score in acute appendicitis: a prospective pediatric cohort

PURPOSE

To evaluate whether C-reactive protein (CRP) level and ultrasound (US) results on admission could aid the diagnostic accuracy of Alvarado score.

METHODS

A prospective study was performed on children <14 years admitted for suspected acute appendicitis. Patients were categorized into three groups based on the Alvarado score: group I: score 7-10, group II: score 5-6, group III: score 0-4.

RESULTS

The difference between predictive values of Alvarado score alone and Alvarado score with CRP was not statically significant. The PPV increased from 74.29% (Alvarado score and CRP) to 93.75% (Alvarado score and US) in group 1 (P = .001) and the NPV increased from 64.86 and 79.69% (Alvarado score and CRP) to 82.6 and 88.2% (Alvarado score and US) in group 2 (P = .01) and group 3 (P = .001), respectively.

CONCLUSIONS

Alvarado score and ultrasound taken together improve the predictive value of diagnosing acute appendicitis in children.

Evaluation of acute appendicitis by pediatric emergency physician sonography

STUDY OBJECTIVE

We investigate the accuracy of pediatric emergency physician sonography for acute appendicitis in children.

METHODS

We prospectively enrolled children requiring surgical or radiology consultation for suspected acute appendicitis at an urban pediatric emergency department. Pediatric emergency physicians performed focused right lower-quadrant sonography after didactics and hands-on training with a structured scanning algorithm, including the graded-compression technique. We compared their sonographic interpretations with clinical and radiologic findings, as well as clinical outcomes as defined by follow-up or pathologic findings.

RESULTS

Thirteen pediatric emergency medicine sonographers performed 264 ultrasonographic studies, including 85 (32%) in children with pathology-verified appendicitis. Bedside sonography had a sensitivity of 85% (95% confidence interval [CI] 75% to 95%), specificity of 93% (95% CI 85% to 100%), positive likelihood ratio of 11.7 (95% CI 6.9 to 20), and negative likelihood ratio of 0.17 (95% CI 0.1 to 0.28).

CONCLUSION

With focused ultrasonographic training, pediatric emergency physicians can diagnose acute appendicitis with substantial accuracy.