Ultrasound of paediatric appendicitis and its secondary sonographic signs: providing a more meaningful finding

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.

Optimizing the Use of Computed Tomography for Appendicitis Diagnosis in the Pediatric Emergency Department Through the Quality Improvement Methodology

BACKGROUND

Acute appendicitis is one of the most common causes of an acute abdomen among pediatric patients. The diagnosis of appendicitis is challenging due to the nonspecific presentation. Diagnosis is based on historical, physical, and serologic information as well as right lower quadrant ultrasound (RLQ US). In equivocal patients, or those with a high degree of suspicion, computed tomography (CT) of the abdomen and pelvis with intravenous (IV) contrast can be utilized to rule in appendicitis. However, optimizing diagnostic protocols to minimize ionizing radiation exposure while maintaining diagnostic accuracy is important.

METHODS

We performed a monthly retrospective analysis of CT usage among pediatric patients with suspected acute appendicitis presenting to the pediatric emergency department (ED) from June 2023 to December 2023. We used quality improvement methodology to decrease CT use with monthly Plan-Do-Study-Act (PDSA) cycles with an aim to decrease CT use by 50%. The main intervention was coordination between the ED and surgical providers to require surgical consult before ordering a CT. We quantified the number of patients who received a surgical consult before CT, the number of RLQ US performed, the number of CTs performed, and the number of appendectomies, specifically the number with perforation.

RESULTS

A total of 249 patients under 18 years of age presented to the pediatric ED with symptoms of acute appendicitis during the study period. All 249 patients underwent an initial RLQ US. The number of CTs performed decreased from a baseline of 14 in June to a nadir of four in September (71% decrease, p=0.029). There was a decrease in the percentage of patients who underwent a CT scan after an RLQ US from 36.5% in June to 11.8% in September after our intervention. In June, a total of 38 RLQ US were performed and 14 patients underwent additional CT (36.5%) and in September a total of 34 US were performed and 14 patients underwent additional CT (11.8%). There was an increase in the surgical consults rate from a baseline of seven surgical consults with 14 total CTs in June 2023 (50%) to seven consults with a total of seven CTs performed (100%) in December 2023. There was no increase in appendiceal perforation rates.

CONCLUSION

Multidisciplinary discussions between pediatric ED physicians and pediatric surgeons reduced CT usage, and corresponding radiation exposure and cost, in the evaluation of appendicitis.

Partial visualization of appendix on ultrasound: What does it mean in the child with suspected appendicitis?

BACKGROUND

Visualization of the entire appendix, including the tip, is thought, but has not been demonstrated, to be important for exclusion of appendicitis by ultrasound.

OBJECTIVE

To determine if incomplete visualization of the appendix has negative clinical ramifications including missed appendicitis.

METHODS

Under IRB approval we retrospectively reviewed right lower quadrant ultrasound reports from January 2017 to December 2020 to identify examinations with impressions of full visualization of the normal appendix, non-visualization of the appendix with and without secondary findings of appendicitis, and partial visualization of the appendix. Electronic health records were reviewed for follow-up imaging within 48 h, and surgery with pathology reports (if available).

RESULTS

12,193 examinations were included. 4171 (34.2 %) had full visualization of a normal appendix, 5369 (44.0 %) had non-visualization with no secondary findings, and 234 (1.9 %) had non-visualization with secondary findings, The frequencies of appendicitis in these three groups were 34 (0.8 %), 283 (5.3 %), and 127 (54.3 %) respectively. The appendix was partially visualized in 338 (2.8 %) patients with secondary findings present in 53 (15.6 %). Partial visualization without secondary findings had a similar frequency (4.9 %, 14/285) of appendicitis to non-visualized appendix without secondary findings (p = 0.797) and a higher frequency than full visualization of a normal appendix (p < 0.0001). Partial visualization with secondary findings had similar rates (54.7 %, 29/53) to non-visualized appendix with secondary findings (p = 0.953).

CONCLUSION

Partial visualization of the appendix with ultrasound (with and without secondary findings) is associated with similar frequencies of appendicitis as non-visualization of appendix (with and without secondary findings).

Ultrasound Assessment in Children With Suspected Appendicitis: Time to Revise Diagnostic Criteria: A Prospective Cohort Study

Background: Although ultrasound is considered the gold standard for the evaluation of children with suspected appendicitis, there is still much debate about the most accurate ultrasound findings. The purpose of this study was to define the best ultrasound signs that could ultimately improve the diagnostic accuracy of ultrasound for diagnosing pediatric acute appendicitis, and to differentiate between simple appendicitis and complicated appendicitis. Patients and Methods: After approval by our Institutional Review Board, a prospective study was carried out from January 1, 2022, to July 31, 2023, in a pediatric emergency department. We included all patients aged under 14 years with suspected appendicitis and ultrasound-visualized appendix. Results: A total of 550 patients presented with suspected appendicitis during the study period. Of these children, 411 had an ultrasound-visualized appendix. Our patients' mean age was 9.4 years. The best positive predictive value of ultrasound was found for appendiceal diameter ≥7.5 mm. The combination of an appendiceal diameter <6 mm and the lack of peri-appendiceal free fluid on ultrasound rules out the diagnosis of appendicitis. The best diagnostic accuracy of ultrasound, which was 92%, was achieved for appendix diameters ≥6.5 mm. The sonographic sign giving the best ultrasound accuracy for diagnosing complicated appendicitis was an appendix diameter ≥9 mm. Conclusions: In conclusion, our present study demonstrated that appendiceal diameter ≥6.5 mm is the gold standard for diagnosing appendicitis in pediatric patients. The combination of an appendiceal diameter <6 mm and the lack of peri-appendiceal free fluid on ultrasound would rule out appendicitis.

Interpretable and intervenable ultrasonography-based machine learning models for pediatric appendicitis

Appendicitis is among the most frequent reasons for pediatric abdominal surgeries. Previous decision support systems for appendicitis have focused on clinical, laboratory, scoring, and computed tomography data and have ignored abdominal ultrasound, despite its noninvasive nature and widespread availability. In this work, we present interpretable machine learning models for predicting the diagnosis, management and severity of suspected appendicitis using ultrasound images. Our approach utilizes concept bottleneck models (CBM) that facilitate interpretation and interaction with high-level concepts understandable to clinicians. Furthermore, we extend CBMs to prediction problems with multiple views and incomplete concept sets. Our models were trained on a dataset comprising 579 pediatric patients with 1709 ultrasound images accompanied by clinical and laboratory data. Results show that our proposed method enables clinicians to utilize a human-understandable and intervenable predictive model without compromising performance or requiring time-consuming image annotation when deployed. For predicting the diagnosis, the extended multiview CBM attained an AUROC of 0.80 and an AUPR of 0.92, performing comparably to similar black-box neural networks trained and tested on the same dataset.

Predictors of Complicated Appendicitis with Evolution to Appendicular Peritonitis in Pediatric Patients

Background and Objecitves: Appendicitis is one of the most frequent surgical emergencies in pediatric surgery. Complicated appendicitis can evolve with appendicular peritonitis characterized by the diffusion of the pathological process to the peritoneal cavity, thus producing generalized or localized inflammation of the peritoneum. The capacity to anticipate the possibility of perforation in acute appendicitis can direct prompt management and lower morbidity. There is no specific symptom that could be used to anticipate complicated appendicitis, and diagnostic clues include a longer period of symptoms, diffuse peritoneal signs, high fever, elevated leukocytosis and CRP, hyponatremia, and high ESR. Imagistic methods, particularly US and CT, are useful but not sufficient. There are no traditional inflammation biomarkers able to predict the evolution of uncomplicated to complicated appendicitis alone, but the predictive capacity of novel biomarkers is being investigated. Materials and Methods: The present study represents a retrospective evaluation of children hospitalized between January 2021 and July 2022 in the Grigore Alexandrescu Clinical Emergency Hospital for Children with a diagnosis of acute appendicitis settled based on clinical characteristics, traditional and novel biomarkers, and ultrasonographic features. The children were subsequently grouped into two groups based on the existence of appendicular peritonitis on intraoperative inspection of the abdominal cavity. The aim of this report is to establish the predictors that may aid physicians in timely identifying pediatric patients diagnosed with acute appendicitis at risk for developing complicated appendicitis with evolution to appendicular peritonitis. Results: The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte radio (PLR) are representative severity markers in infections. This report analyzes the benefit of these markers for distinguishing uncomplicated appendicitis from complicated appendicitis in pediatric patients. Conclusions: Our study suggests that a value of neutrophil-to-lymphocyte ratio greater than 8.39 is a reliable parameter to predict the evolution to appendicular peritonitis.

Association of Gallbladder Volume and Wall Thickness With Acute Appendicitis in Pediatric Patients

OBJECTIVES

Ultrasonography in a child with suspected appendicitis is primarily performed to detect inflamed appendix, whereas secondary findings are important in patients with a nonvisualized appendix. The aim of this study is to evaluate the gallbladder wall thickness and volume in patients with suspected appendicitis and search an association between these parameters and appendicitis.

METHODS

Between January 2018 and August 2018, 113 patients with suspected appendicitis were included in this prospective study. Gallbladder and right lower quadrant were evaluated in separate sessions by different radiologists. The wall thickness along with the width, length, and height of the gallbladder was measured and recorded for each patient. Assessment of the appendix was classified as acute appendicitis, normal, and equivocal. Statistically significant association was sought between the thickness of the gallbladder wall and diagnosis of appendicitis.

RESULTS

Gallbladder wall thickness was significantly higher in patients without appendicitis (P = 0.017), whereas significantly increased gallbladder volume was observed in patients with appendicitis (P = 0.004). Receiver operating characteristic analysis showed gallbladder wall thickness threshold of 0.5 mm with a sensitivity of 83.3, specificity of 93.9, and volume threshold of 41.6 mL with a sensitivity of 100 and a specificity of 0.69.

CONCLUSIONS

Gallbladder wall thickness and volume measurements were associated with the diagnosis of appendicitis in pediatric patients.

The use of a pediatric appendicitis pathway in a large integrated health system reduced computed tomography imaging in the ED

BACKGROUND

Appendicitis is the most common cause of an acute surgical abdomen in children. Diagnosis is often challenging as few pediatric patients present with classic symptoms. Clinicians are thus dependent on imaging to reach an accurate diagnosis. Although computerized tomography (CT) has high sensitivity and specificity, it has the disadvantage of imparting ionizing radiation. Ultrasound (US) is readily available and has comparable accuracy to CT when performed by experienced sonographers. We sought to examine the impact of a system-wide process improvement plan on CT use and other metrics in pediatric patients who presented to the Emergency Department (ED) with suspected appendicitis.

METHODS

This is a retrospective study of the impact of a Pediatric Appendicitis Pathway (PAP) within a large integrated hospital system with 12 EDs including 3 designated hub EDs. Patients were placed in an initial risk category utilizing the Pediatric Appendicitis Score (PAS), and received US of the appendix at a hub ED if indicated by the PAS. Patients presenting to community EDs who required US appendix were transferred to hub EDs for imaging. Patients presenting in the 6-month pre-implementation period were compared to patients presenting in a 14-month post-implementation period on CT and US utilization, negative and missed appendectomy rates, and ED length of stay (LOS).

RESULTS

1874 patients (401 pre-PAP and 1473 post-PAP) were included in the study. At the hub EDs the rate of CT imaging for suspected appendicitis was reduced from 31% to 17% with a resultant increase in US utilization from 83% (333/401) to 90% (1331/1473) (p < 0.001). At community general EDs (404 pre-PAP and 449 post-PAP), the rate of CT was decreased from 45% (181/404) to 32%(144/449) (p < 0.001)) There was no significant change in the negative appendectomy rate pre-PAP (1/59 = 1.7%) and post-PAP (4/168 = 2.4%) (p = 0.99) at the hub EDs. There were no missed appendicitis cases after PAP implementation compared to 1 case in the pre-PAP period. Overall LOS was similar pre and post-PAP, however LOS was longer in patients that required transfer from community general EDs to hub EDs (median 264 vs 342 min, p < 0.001).

CONCLUSIONS

A PAP that stratified patients into risk groups using the PAS and encouraged the use of US as a first line imaging modality, reduced the number of CT performed in a large integrated health system without significant changes to clinical outcomes. Furthermore, transferring select patients for an US as opposed to obtaining an initial CT in community general EDs was feasible and reduced CT use in the pediatric population.

New Oxidative Stress Markers Useful in the Diagnosis of Acute Appendicitis in Children: Thiol/Disulfide Homeostasis and the Asymmetric Dimethylarginine Level

OBJECTIVES

The aim of this study was to evaluate 2 new oxidative stress markers, thiol/disulfide homeostasis status and the asymmetric dimethylarginine (ADMA) level, in children with acute appendicitis (AA) and to evaluate their diagnostic utility.

METHODS

This case-control study included 45 patients with AA and 35 healthy children. Age, sex, white blood cell count, neutrophil-to-lymphocyte ratio, high-sensitivity C-reactive protein (hs-CRP) level, ultrasonographic findings, thiol/disulfide homeostasis parameters (native and total thiol levels, native thiol/total thiol ratios [antioxidant parameters], and disulfide, disulfide/native thiol, and disulfide/total thiol ratios [oxidant parameters]), and the ADMA level were compared between the 2 groups.

RESULTS

The native and total thiol levels, and the native thiol/total thiol ratio, were significantly lower, and the disulfide level and disulfide/native thiol and disulfide/total thiol ratios significantly higher, in the AA compared with the control group (all P < 0.001). The ADMA level was significantly higher in a perforated versus nonperforated subgroup of AA patients, but the thiol/disulfide homeostasis parameters did not differ significantly between the two subgroups. In addition, the hs-CRP level and appendiceal wall thickness were higher in the perforated subgroup. The thiol/disulfide antioxidant parameters and ADMA level correlated negatively with the white blood cell count, the neutrophil-to-lymphocyte ratio, and the hs-CRP level, in the AA group, but correlated positively with oxidant parameters. The sensitivity and specificity of the disulfide/native thiol and disulfide/total thiol ratios were high when used to diagnose AA, whereas the sensitivity of the ADMA level was high when used to diagnose perforated appendicitis.

CONCLUSIONS

Thiol/disulfide homeostasis and the ADMA level, together with certain other parameters, may be useful biomarkers of AA in children.

Ultrasonography in diagnosis of appendicitis and its complications in pediatric patients: a cross-sectional study

Background

Appendicitis is a common cause of acute abdomen in pediatrics. Although various criteria have been suggested in early diagnosis of appendicitis, these criteria are not as applicable for pediatric patients. Because of this, imaging has an important role in the diagnosis of appendicitis in pediatric patients. The present study was conducted on 121 pediatric patients with possible diagnosis of appendicitis. All of the patients underwent initial evaluation and then underwent sonographic imaging. Sonography was used to assess the existence of signs associated with appendicitis, or its complications. Imaging findings were compared in patients with complications with those with complications. True false positive, false negative, true positive, and true negative values were calculated. Sensitivity and specificity of ultrasonography in determining appendicitis was evaluated.

Results

The mean age of children was 8.08 ± 3.25 years, with ages ranging from 3 to 14 years. Of the 121 children, 74(61.2%) were male and 47(38.8%) were female. In total, there were 3(2.4%) false positives and 2(1.6%) false negatives based on sonographic findings. There were also 54(44.6%) true positive and 62(51.2%) true negative based on sonographic findings. Based on the findings of ultrasound in this study, ultrasound sensitivity was 96.4%, specificity was 95.3%, positive predictive value was 94.7%, and negative predictive value was 96.8%.

Conclusion

Ultrasonography is indicated in the diagnosis of appendicitis in pediatric patients and has optimal sensitivity and specificity in the diagnosis. Furthermore, it is a suitable diagnostic method for evaluating complications of appendicitis.

Aeromedical retrieval for suspected appendicitis in rural and remote paediatric patients

Introduction

The aim of this paper was to describe the characteristics of paediatric patients who underwent an aeromedical retrieval within Australia (gender and Indigenous status) for suspected appendicitis between 1 July 2014 and 30 June 2018 (4 years). By understanding these trends, we hope to further justify the need for point-of-care ultrasound training for clinicians working in rural and remote Australia.

Method

Participants included Royal Flying Doctor Service (RFDS) patients aged 0-18 years (inclusive) who underwent an aeromedical retrieval for suspected appendicitis within Australia. Data were collected and coded on each patient's inflight working diagnosis, using the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification (ICD-10-AM) coding method. A combination of descriptive statistics and chi-square analyses was used in data analysis, with significance considered at <0.05.

Results

There were 384 children with a working diagnosis of suspected appendicitis, including 191 (49.7%) males and 193 (50.3%) females, with 133 (34.6%) patients identifying as Aboriginal and/or Torres Strait Islander (hereafter referred to as Indigenous) Australians. The aeromedical retrievals were from rural and remote locations to inner-regional or metropolitan hospitals, with an average distance flown of 339.0 (SD = 206.4) kilometres. The RFDS most frequently retrieved for acute appendicitis (n = 159; 41.4%), acute abdominal pain (n = 127; 33.1%), and unspecified appendicitis (n = 84; 21.9%). There were non-significant (P = 0.9) diagnostic differences between genders. Non-Indigenous patients were overrepresented, compared with Indigenous patients, in relation to a transfer with a diagnosis of acute appendicitis (P = <0.01), whereas Indigenous patients were overrepresented, compared with non-Indigenous patients, in relation to transfers with diagnoses of acute abdomen pain and unspecified appendicitis (P = <0.01).

Conclusion

A significant number of paediatric patients are aeromedically retrieved from rural and remote locations with a diagnosis of appendicitis or acute abdominal pain. Future research should consider whether training in abdominal point-of-care ultrasound reduces retrievals.

The Modified Heidelberg and the AI Appendicitis Score Are Superior to Current Scores in Predicting Appendicitis in Children: A Two-Center Cohort Study

Background: Acute appendicitis represents the most frequent reason for abdominal surgery in children. Since diagnosis can be challenging various scoring systems have been published. The aim of this study was to evaluate and validate (and improve) different appendicitis scores in a very large cohort of children with abdominal pain. Methods: Retrospective analysis of all children that have been hospitalized due to suspected appendicitis at the Pediatric Surgery Department of the Altonaer Children's Hospital and University Medical Center Hamburg-Eppendorf from 01/2018 until 11/2019. Four different appendicitis scores (Heidelberg Appendicitis Score, Alvarado Score, Pediatric Appendicitis Score and Tzanakis Score) were applied to all data sets. Furthermore, the best score was improved and artificial intelligence (AI) was applied and compare the current scores. Results: In 23 months, 463 patients were included in the study. Of those 348 (75.2%) were operated for suspected appendicitis and in 336 (96.6%) patients the diagnosis was confirmed histopathologically. The best predictors of appendicitis (simple and perforated) were rebound tenderness, cough/hopping tenderness, ultrasound, and laboratory results. After modifying the HAS, it provided excellent results for simple (PPV 95.0%, NPV 70.0%) and very good for perforated appendicitis (PPV 34.4%, NPV 93.8%), outperforming all other appendicitis score. Discussion: The modified HAS and the AI score show excellent predictive capabilities and may be used to identify most cases of appendicitis and more important to rule out perforated appendicitis. The new scores outperform all other scores and are simple to apply. The modified HAS comprises five features that can all be assessed in the emergency department as opposed to current scores that are relatively complex to utilize in a clinical setting as they include of up to eight features with various weighting factors. In conclusion, the modified HAS and the AI score may be used to identify children with appendicitis, yet prospective studies to validate our findings in a large mutli-center cohorts are needed.

Bayesian Approach to Predicting Acute Appendicitis Using Ultrasonographic and Clinical Variables in Children

Objectives

Ultrasound has an established role in the diagnostic pathway for children with suspected appendicitis. Relevant clinical information can influence the diagnostic probability and reporting of ultrasound findings. A Bayesian network (BN) is a directed acyclic graph (DAG) representing variables as nodes connected by directional arrows permitting visualisation of their relationships. This research developed a BN model with ultrasonographic and clinical variables to predict acute appendicitis in children.

Methods

A DAG was designed through a hybrid method based on expert opinion and a review of literature to define the model structure; and the discretisation and weighting of identified variables were calculated using principal components analysis, which also informed the conditional probability table of nodes.

Results

The acute appendicitis target node was designated as an outcome of interest influenced by four sub-models, including Ultrasound Index, Clinical History, Physical Assessment, and Diagnostic Tests. These sub-models included four sonographic, three blood-test, and six clinical variables. The BN was scenario tested and evaluated for face, predictive, and content validity. A lack of similar networks complicated concurrent and convergent validity evaluation.

Conclusions

To our knowledge, this is the first BN model developed for the identification of acute appendicitis incorporating imaging variables. It has particular benefit for cases in which variables are missing because prior probabilities are built into corresponding nodes. It will be of use to clinicians involved in ultrasound examination of children with suspected appendicitis, as well as their treating clinicians. Prospective evaluation and development of an online tool will permit validation and refinement of the BN.

Comparison of the use of Alvarado and AIR scores as an adjunct to the clinical diagnosis of acute appendicitis in the pediatric population

Background

Acute appendicitis is one of the most common causes of acute abdominal pain with an incidence of 1.17 per 1000 and lifetime risk of approximately 7%. It remains the most common indication for emergency abdominal surgery in childhood. Diagnosis of acute appendicitis is particularly difficult in young women and the pediatric population. In the USA, CT imaging is used to avert diagnostic dilemma, however the procedure is associated with radiation risk in this vulnerable population. Additionally, the procedure has high cost and variable availability.

Methods

A retrospective study involving all suspected pediatric cases of appendicitis between the ages of 5 and 17 who were operated on between 2012 and 2015 was carried out. Data were collated from clinical notes on age, sex, ultrasound findings; postoperative complications, white cell count, neutrophils, C-reactive protein, histology result, and number of days to theater. All patients in the time period were retrospectively scored on the Alvarado and Appendicitis Inflammatory Response (AIR) scores.

Results

A total of 239 patients between 11 and 17 (mean 13.6±SE) years of age were included in the study. Of these, 79 had preoperative ultrasound, of which 52 were negative, and only one patient had CT scan. 213 of the patients had an appendicectomy and 26 had diagnostic laparoscopy with no appendicectomy. Of the 213 appendixes removed, 71 were histopathologically normal, giving a negative appendectomy rate of 33.3%. 28 appendixes were perforated. The average number of days from admission to theater was 1.0 SE in males and 1.424 in females (p=0.0498). The average number of days from admission to theater in those who had ultrasound was 2.03 days compared with 0.75 in those who did not have ultrasound (p<0.0001). AIR scoring that was high and medium risk showed slightly lower negative appendicectomy rates but not significantly different.

Conclusions

Our study has found no significant difference between the AIR scores and Alvarado. There is a role for scoring systems to be used to aid in the decision to undergo imaging and as an adjunct to clinical diagnosis.

Clinical outcomes following identification of tip appendicitis on ultrasonography and CT scan

BACKGROUND/PURPOSE

With recent improvements in imaging technology, subtler variations in the anatomy of the appendix can be appreciated. We hypothesized that radiographic findings of tip appendicitis may not correlate strongly with a pathologic diagnosis of appendicitis.

METHODS

Our radiology database was searched for reports of a diagnosis of tip appendicitis between January 2013 and June 2017 for patients between the ages of 2 and 17. Retrospective chart review was performed for demographic and clinical data, including outcomes. For patients managed operatively, the pathology results were reviewed for evidence of acute appendicitis. Patients managed nonoperatively and those with negative pathology were considered to not have appendicitis.

RESULTS

Fifty-five patients met inclusion criteria (31 boys and 24 girls); 46/55 patients with tip appendicitis on imaging ultimately did not have appendicitis. Twenty-one patients underwent appendectomy, and 9/21 had pathologic evidence of appendicitis. One patient had a ruptured appendix. No other pathology was identified in the negative appendectomies. Two patients managed nonoperatively required readmission, but not secondary to missed diagnosis of appendicitis.

CONCLUSIONS

Ultrasound and CT findings of tip appendicitis may not accurately associate with a final diagnosis of acute appendicitis. Clinical judgment should ultimately dictate appropriate initial management, follow-up tests, and imaging.

TYPE OF STUDY

Diagnostic Study.

LEVEL OF EVIDENCE

Level III.

Utility and Accuracy of Primary and Secondary Ultrasonographic Signs for Diagnosing Acute Appendicitis in Pediatric Patients

Introduction

Making an accurate diagnosis of acute appendicitis (AA) is vital to prevent the morbid complications associated with untreated AA. This is challenging in up to 30% of pediatric patients which is a significantly high number. Ultrasound (US) has been generally used as the initial mode of imaging in pediatric patients due to the lack of ionizing radiation. Given its variable accuracy, adjuvants such as secondary signs can be used to aid the radiologist in making an accurate diagnosis.

Materials and methods

Patients between the ages of two and sixteen years with acute abdominal pain suspicious for AA, who underwent right lower quadrant US between 2003 and 2016, were retrospectively identified. Corresponding computed tomography (CT) and histopathology findings were noted. Based on the presence of primary and secondary signs, results were classified into three groups to determine accuracy. Group 1 included all patients with a normal appendix or if the appendix was not visualized, no secondary signs were present. Group 2 patients were those in which the appendix was not clearly seen and they had one or more secondary signs of AA. Group 3 included all patients with primary signs of AA. The number of secondary signs and cases with perforated appendices were also correlated with sonographic accuracy.

Results

One thousand one hundred and fifteen patients met the inclusion criteria of which 29% had confirmatory AA. The positive appendectomy rate was 89% (337/380). Using a 3-category classification of US results, the sensitivity was 79%, specificity 97%, positive predictive value was 93%, negative predictive value was 91% and the overall accuracy was 91%. The presence of two or more secondary signs had a high likelihood of appendicitis. The perforation rate was 10% with the highest percentage seen in Group 2 patients.

Conclusion

Despite inescapable limiting factors, US should be used as first-line imaging for suspected appendicitis in pediatric patients especially since its accuracy rivals CT when the appendix is visualized. The use of secondary sonographic signs has solid potential to aid the radiologist in making an accurate diagnosis with our study demonstrating a proportional relationship between the number of secondary signs and the likelihood of true appendicitis. However, further investigation is needed to determine the individual accuracy of secondary signs and whether a certain combination of secondary signs has a higher association with appendicitis.

Paediatric appendiceal ultrasound: a survey of Australasian sonographers' opinions on examination performance and sonographic criteria

INTRODUCTION

The objectives of this study were to identify knowledge gaps and/or perceived limitations in the performance of paediatric appendiceal ultrasound by Australasian sonographers. We hypothesised that: sonographers' confidence in visualising the appendix in children was poor, particularly outside predominantly paediatric practice; workplace support for prolonging examinations to improve visualisation was limited; and the sonographic criteria applied in diagnosis did not reflect contemporary literature.

METHODS

A cross-sectional survey of Australasian sonographers regarding paediatric appendicitis was conducted using a mixed methods approach (quantitative and qualitative data). Text responses were analysed for key themes, and quantitative data analysed using chi-square, Mann-Whitney U and Wilcoxon signed-rank tests.

RESULTS

Of the 124 respondents, 27 (21.8%) reported a visualisation rate of less than 10%. Workplace support for extending examination time was significantly related to a higher appendix visualisation rate (χ2 (2) = 16.839, P < 0.001). Text responses reported frustration locating the appendix and a desire for more time and practice to improve visualisation. Sonographers suggested a significantly lower maximum diameter cut-off in a 5-year-old compared to a 13-year-old (Z = -6.07, P < 0.001), and considered the presence of inflamed peri-appendiceal mesentery as the most useful sonographic criterion in diagnosing acute appendicitis.

CONCLUSIONS

Respondents had a low opinion of their ability to confidently identify the appendix. Confidence was greater in those centres where extending scanning time was encouraged. Application of echogenic mesentery as the most significant secondary sonographic criterion is supported by recent studies. Opinions of diameter cut-offs varied, indicating potential for improved awareness of recent research.

Improving the value of ultrasound in children with suspected appendicitis: a prospective study integrating secondary sonographic signs

PURPOSE

The purpose of this study was to determine whether the awareness and inclusion of secondary sonographic signs of appendicitis, in combination with a structured evaluation as part of engagement and training for sonographers, improved appendix visualization rates and reduced equivocal findings in children with suspected acute appendicitis.

METHODS

This was a prospective study of 230 children at a tertiary children's hospital in Australia referred for an ultrasound examination of suspected appendicitis. The ultrasound findings, radiology reports, histology, clinical results, and follow-up were collated. Secondary signs were used as an additional assessment of the likelihood of disease where possible, even in the absence of an identified appendix.

RESULTS

The implementation of a structured evaluation as part of sonographer engagement and training resulted in a 28% improvement in appendix visualization (68.7%) compared with a prior retrospective study in a similar population (40.7%). The diagnostic accuracy was 91.7%, with likelihood ratios suggesting a meaningful influence of the pre-test probability of appendicitis in children studied (positive likelihood ratio, 11.22; negative likelihood ratio, 0.09.). Only 7.8% of the findings were equivocal. A binary 6-mm diameter cut-off did not account for equivocal cases, particularly lymphoid hyperplasia.

CONCLUSION

Engagement of sonographers performing pediatric appendiceal ultrasound through training in the scanning technique and awareness of secondary signs significantly improved the visualization rate and provided more meaningful findings to referrers.

Dilemma of mucosal appendicitis: a clinico-pathological entity? A retrospective cohort study

BACKGROUND

The presence of mucosal inflammation within appendicectomy specimens is poorly described in the literature, and there is debate regarding the clinical significance of this histological finding. The aim of this study is to correlate clinical and radiological data with histologically confirmed acute mucosal appendicitis (MA).

METHODS

A retrospective cohort study was performed to identify all patients who underwent appendicectomy over 5 years at Caboolture Hospital. Data were collected in regards to clinical Alvarado score, pathological specimen findings, radiological findings and coincidental conditions, and comparison made between MA and negative appendicectomy groups.

RESULTS

A total of 1347 appendicectomy specimens and data were reviewed. Of these, 219 (16%) specimens were microscopically confirmed to have acute mucosal inflammation, 150 (68%) were females. Median age was 19 ± 14 years. A total of 243 (18%) were histologically negative. There was a statistically significant difference in mean Alvarado score in the MA group (5.0 ± 1.9 versus 4.3 ± 1.8, P = 0.0002). Patients with MA are more likely to report migratory pain (48.4 versus 31.4%, P = 0.0001) and rebound tenderness (24.9 versus 14.6%, P = 0.002). Computed tomography and ultrasound scans were negative in 74.1 and 72.6%, respectively, in patients with MA. More MA patients benefited from appendicectomy compared with the negative appendicectomy group (82 versus 63%, P = <0.0001).

CONCLUSION

There is a subgroup of patients with MA who are young females with have low Alvarado scores, have non-diagnostic imaging, and may represent almost one-fifth of appendicectomy specimens. This study supports the probability that MA is a pathological entity.

Ultrasound of paediatric appendicitis and its secondary sonographic signs: providing a more meaningful finding

Sonography is an important clinical tool in diagnosing appendicitis in children as it can obviate both exposure to potentially harmful ionising radiation from computed tomography scans and the need for unnecessary appendicectomies. This review examines the diagnostic accuracy of ultrasound in the identification of acute appendicitis, with a particular focus on the the utility of secondary sonographic signs as an adjunct or corollary to traditionally examined criteria. These secondary signs can be important in cases where the appendix cannot be identified with ultrasound and a more meaningful finding may be made by incorporating the presence or absence of secondary sonographic signs. There is evidence that integrating these secondary signs into the final ultrasound diagnosis can improve the utility of ultrasound in cases where appendicitis is expected, though there remains some conjecture about whether they play a more important role in negative or positive prediction in the absence of an identifiable appendix.

Ultrasonography-triggered diagnosis of putrid, ulcero-phlegmonous, hemorrhagic appendicitis and periappendicitis with an atypical symptom pattern: a case report

BACKGROUND

Asymptomatic and oligosymptomatic appendicitis are rare and challenging diagnoses that should not be missed.

CASE PRESENTATION

A young female patient presented with mild to moderate pain in the middle and lower abdomen, and the results of physical examination, including digital rectal examination, were otherwise non-contributory. Ultrasonography demonstrated a marked increase of the outer appendiceal diameter up to 12 mm and a trace of free liquid around the terminal ileum. Subsequent surgical exploration and histological examination allowed for a final diagnosis of putrid, ulcero-phlegmonous, hemorrhagic appendicitis and periappendicitis.

CONCLUSIONS

Ultrasonography is increasingly used for the diagnosis of appendiceal inflammation, particularly in military medical settings. Increases in the outer appendiceal diameter up to >6 mm under compression have recently been demonstrated to be indicative of acute appendicitis. At a minimum, in cases with doubtful physical examination results, ultrasonography should be considered as an element in the diagnosis of acute appendicitis.