Diagnostic Accuracy of Abdominal Ultrasound for Diagnosis of Acute Appendicitis: Systematic Review and Meta-analysis

Evaluating the Diagnostic Accuracy of the Alvarado Score and Abdominal Ultrasound for Acute Appendicitis: A Retrospective Single-Center Study

Background

Acute appendicitis is a complex diagnosis that often requires both clinical and radiological evaluation. Significant variations in diagnostic approaches are evident among clinicians and healthcare institutions. While certain guidelines advocate for risk stratification based on clinical characteristics, others emphasize the importance of pre-operative imaging. This study seeks to explore the accuracy of the Alvarado Score and abdominal ultrasound (AUS) in diagnosing acute appendicitis.

Methods

Suspected cases of appendicitis admitted to Al-Thora Hospital in Ibb, Yemen, from Jan 2021 to July 2022 were evaluated. The demographics, clinical, and laboratory data were collected and analyzed. This study assessed Alvarado scores (calculated based on clinical evaluation and laboratory data) and pre-operative AUS findings, correlating them with post-operative and histopathology findings. The Alvarado scores and AUS sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were assessed using the ROC curve.

Results

Out of 1021 cases of acute abdomen, 171 patients were suspected of appendicitis. Using AUS along with the Alvarado score, appendicitis was presumed in 137 patients who underwent appendectomy. 130 (94.9%) patients had positive intraoperative and histopathology findings while 7 (5.1%) had negative findings. The Alvarado Score had a sensitivity and specificity of 94.62% and 87.80% at cutoffs of 6, respectively [Area under the curve (AUC): 0.985; 95% confidence interval (CI), 0.954 to 0.998; p < 0.0001]. Abdominal US showed a sensitivity of 98.46% and specificity of 82.93% (AUC:0.907; 95% CI, 0.853 to 0.946; p < 0.0001).

Conclusion

Alvarado's score and AUS exhibited high sensitivity and specificity in diagnosing acute appendicitis. The substantial accuracy and efficacy of both the Alvarado score and AUS support their utilization as primary investigative tools in resource-limited settings. This approach can help avoid unnecessary appendectomies and minimize the financial burden on patients.

Diagnostic Efficacy Study Comparing Tzanakis Scoring System With Alvarado Scoring System in Effective Diagnosis of Acute Appendicitis

Objective Among the common causes of abdominal emergencies, acute appendicitis ranks at the top, particularly in the young population. While negative appendectomy is not uncommon, the risk of appendicular perforation is substantial if the diagnosis is missed or delayed. This study evaluated the diagnostic efficacy of the Tzanakis scoring system for acute appendicitis, comparing it with the Alvarado scoring system, considering the histopathological finding as the gold standard. Materials and methods This prospective observational study, conducted in the General Surgery department in a tertiary care hospital in India, included clinically diagnosed acute appendicitis cases posted for open or laparoscopic appendicectomy. Results The mean age for the 60 participants included in the study was 30.97±13.44, and the median was 24.5 yrs. The sensitivity of ultrasonography (USG) in diagnosing histopathological positive acute appendicitis was 89%, and the specificity was 50%. The sensitivity, specificity, positive, and negative predictive values of the Tzanakis score were 87%, 50%, 96%, and 22%, respectively, and those of the Alvarado score were 54%, 75%, 96%, and 10%, respectively. Conclusion The receiver operator characteristic (ROC) curve for the Alvarado and Tzanakis scores showed that the area under the curve (AUC) was greater for the Tzanakis scoring system (0.670) than for the Alvarado scoring system (0.598). Differences between the AUCs were not statistically significant. Although the Tzanakis scoring system is more sensitive than the Alvarado scoring system in diagnosing acute appendicitis, studies with larger samples are needed to show the superiority of this scoring system over the Alvarado scoring system.

Development and Validation of a Deep Learning and Radiomics Combined Model for Differentiating Complicated From Uncomplicated Acute Appendicitis

RATIONALE AND OBJECTIVES

This study aimed to develop and validate a deep learning and radiomics combined model for differentiating complicated from uncomplicated acute appendicitis (AA).

MATERIALS AND METHODS

This retrospective multicenter study included 1165 adult AA patients (training cohort, 700 patients; validation cohort, 465 patients) with available abdominal pelvic computed tomography (CT) images. The reference standard for complicated/uncomplicated AA was the surgery and pathology records. We developed our combined model with CatBoost based on the selected clinical characteristics, CT visual features, deep learning features, and radiomics features. We externally validated our combined model and compared its performance with that of the conventional combined model, the deep learning radiomics (DLR) model, and the radiologist's visual diagnosis using receiver operating characteristic (ROC) curve analysis.

RESULTS

In the training cohort, the area under the ROC curve (AUC) of our combined model in distinguishing complicated from uncomplicated AA was 0.816 (95% confidence interval [CI]: 0.785-0.844). In the validation cohort, our combined model showed robust performance across the data from three centers, with AUCs of 0.836 (95% CI: 0.785-0.879), 0.793 (95% CI: 0.695-0.872), and 0.723 (95% CI: 0.632-0.802). In the total validation cohort, our combined model (AUC = 0.799) performed better than the conventional combined model, DLR model, and radiologist's visual diagnosis (AUC = 0.723, 0.755, and 0.679, respectively; all P < 0.05). Decision curve analysis showed that our combined model provided greater net benefit in predicting complicated AA than the other three models.

CONCLUSION

Our combined model allows the accurate differentiation of complicated and uncomplicated AA.

Diagnostic Ultrasound for Acute Appendicitis: The Gold Standard

BACKGROUND

Acute appendicitis may present a diagnostic dilemma. The aim of this study was to review the accuracy of ultrasound in the diagnosis of paediatric acute appendicitis.

METHOD

Ultrasound studies performed for investigation of appendicitis during 2015-2021 were retrieved from a tertiary paediatric hospital database and reviewed. Medical records were reviewed to determine operative intervention, further imaging, and final diagnosis. Diagnostic accuracy was assessed by sensitivity, specificity, predictivity, and overall accuracy. All appendicectomy specimens underwent histopathological confirmation. This study was approved by the local Human Research Ethics Committee.

RESULTS

A total of 8555 consecutive ultrasound examinations were performed during the study period. Mean patient age was 10.8 years ( ± 3.7). Overall diagnostic accuracy was 96.1% (8221/8555) with a visualisation rate of 91.0%. Sensitivity and specificity were 96.2% (CI 95.3-97.0%) and 96.1% (CI 95.6-96.5%), respectively. When limited to positive/negative scans, sensitivity was 99.6% (CI 99.2-99.8%) and specificity 99.0% (CI 98.7-99.3%). Positive and negative predictive values were 96.9% and 99.9%, respectively. Repeat ultrasound following a non-diagnostic scan led to a definitive diagnosis in 76.1%. Negative appendicectomy rate was 5.5% overall in children who had undergone pre-operative ultrasound (107/1938), and 4.4% when other surgical pathologies were excluded.

CONCLUSION

Ultrasound examination provides gold-standard accuracy in the diagnosis of paediatric appendicitis and reduces rates of negative appendicectomy. Given the disadvantages of computed tomography and magnetic resonance imaging, ultrasound should be considered the first-line investigation of choice in the diagnosis of acute appendicitis in children.

LEVEL OF EVIDENCE

III.

A different way to diagnosis acute appendicitis: machine learning

<b><br>Indroduction:</b> Machine learning is a branch of artificial intelligence based on the idea that systems can learn from data, identify patterns, and make decisions with minimal human intervention.</br> <b><br>Aim:</b> Our aim is to predict acute appendicitis, which is the most common indication for emergency surgery, using machine learning algorithms with an easy and inexpensive method.</br> <b><br>Materials and methods:</b> Patients who were treated surgically with a prediagnosis of acute appendicitis in a single center between 2011 and 2021 were analyzed. Patients with right lower quadrant pain were selected. A total of 189 positive and 156 negative appendectomies were found. Gender and hemogram were used as features. Machine learning algorithms and data analysis were made in Python (3.7) programming language.</br> <b><br>Results:</b> Negative appendectomies were found in 62% (n = 97) of the women and in 38% (n = 59) of the men. Positive appendectomies were present in 38% (n = 72) of the women and 62% (n = 117) of the men. The accuracy in the test data was 82.7% in logistic regression, 68.9% in support vector machines, 78.1% in k-nearest neighbors, and 83.9% in neural networks. The accuracy in the voting classifier created with logistic regression, k-nearest neighbor, support vector machines, and artificial neural networks was 86.2%. In the voting classifier, the sensitivity was 83.7% and the specificity was 88.6%.</br> <b><br>Conclusions:</b> The results of our study show that machine learning is an effective method for diagnosing acute appendicitis. This study presents a practical, easy, fast, and inexpensive method to predict the diagnosis of acute appendicitis.</br>.

WBC Count vs. CRP Level in Laboratory Markers and USG vs. CT Abdomen in Imaging Modalities: A Retrospective Study in the United Arab Emirates to Determine Which Are the Better Diagnostic Tools for Acute Appendicitis

Introduction Acute Appendicitis (AA) is the most common surgical emergency. Despite the use of various diagnostic parameters, the rate of negative appendectomy remains high (30%). Thus, through our retrospective study, we aim to analyse whether white blood cell (WBC) count or C-reactive protein (CRP) level is more indicative in the confirmation of AA. We also analysed imaging modalities ultrasonography (USG) and computed tomography (CT) of the abdomen to find out which is better for diagnosing AA. Methods Patients with suspected AA admitted for laparoscopic appendectomy in Saqr Hospital, Ras Al Khaimah, United Arab Emirates, during 2019-2020 were included in the study. Patients who had either or both WBC and CRP values were included in the study and their diagnosis was confirmed based on histological appendectomy findings. Data analysis was done using IBM SPSS Statistics for Windows, Version 23.0 (Released 2015; IBM Corp., Armonk, New York, United States), receiver operating characteristic (ROC) curve, and chi-square test as required. p-value of <0.05 was considered statistically significant. Results Out of the 320 patients with suspected AA, WBC had a p-value of 0.8 (insignificant). A total of 228 patients who had elevated WBC had confirmed histological diagnosis of AA, and 152 patients who were tested for CRP and had elevated levels had confirmed histological diagnosis of AA. CRP had a p-value of 0.04 (significant). However, when the ROC curve was used as evidence to see which was a better test, WBC and CRP both had a low area under the curve (AUC), which proved that they were not the most accurate diagnostic marker in diagnosing AA. However, CRP was slightly better than WBC. A total of 266 patients underwent USG abdomen and it had a p-value of 0.4 (insignificant), while 118 patients underwent CT scan, which had a p-value of 0.01 (significant). CT abdomen was statistically proven as a better radiological investigation. Also, when the ROC curve was used to compare USG and CT abdomen, CT again proved to be a better radio diagnostic method for AA. Conclusions From our study, it can be concluded that CRP is better than WBC in ruling in appendicitis and CT abdomen is better than USG in diagnosing appendicitis, but CT abdomen is only next to histological diagnosis in confirming AA. Hence, we recommend doing CRP as the primary laboratory marker for suspected cases of AA. CT abdomen is the ideal imaging modality in cases of suspected AA where clinical examination, laboratory values, and ultrasound examination are inconclusive.

Rapid MRI Abdomen for Assessment of Clinically Suspected Acute Appendicitis in the General Adult Population: a Systematic Review

OBJECTIVES

To perform a systematic review on the use of magnetic resonance imaging (MRI) of the abdomen to evaluate clinically suspected appendicitis in the general adult population. We examined the diagnostic accuracy, the reported trends of MRI use, and the factors that affect the utility of MRI abdomen, including study duration and cost-benefits.

METHODS

We conducted a systematic literature search on PubMed, MEDLINE, Embase, Web of Science, and Cochrane Library databases. We enrolled primary studies investigating the use of MRI in diagnosing appendicitis in the general adult population, excluding studies that predominantly reported on populations not representative of typical adult appendicitis presentations, such as those focusing on paediatric or pregnant populations.

RESULTS

Twenty-seven eligible primary studies and 6 secondary studies were included, totaling 2,044 patients from eight countries. The sensitivity and specificity of MRI for diagnosing appendicitis were 96% (95% CI: 93-97%) and 93% (95% CI: 80-98%), respectively. MRI can identify complicated appendicitis and accurately propose alternative diagnoses. The duration of MRI protocols in each primary study ranged between 2.26 and 30 minutes, and only one study used intravenous contrast agents in addition to the non-contrast sequences. Decision analysis suggests significant benefits for replacing computed tomography (CT) with MRI and a potential for cost reduction. Reported trends in MRI usage showed minimal utilisation in diagnostic settings even when MRI was available.

CONCLUSIONS

MRI accurately diagnoses appendicitis in the general adult population and improves the identification of complicated appendicitis or alternative diagnoses compared to other modalities using a single, rapid investigation.

Accuracy of ultrasound for the diagnosis of acute appendicitis in the emergency department: A systematic review

BACKGROUND

Point-of-Care Ultrasound (POCUS) is a quick, useful, noninvasive, and inexpensive diagnostic tool used for the diagnosis of trauma, abdominal pain, dyspnea, and chest pain in the emergency department (ED). However, the diagnostic accuracy of ultrasound in the ED may be different from those reported in previous studies owing to the setting and time constraints in ED.

METHODS

We conducted our study in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. A literature search was conducted using databases on US National Library of Medicine's database of biomedical literature, Ovid MEDLINE, online database of biomedical articles, and the collection of databases of systematic reviews and other evidence. The inclusion criteria were the use of bedside ultrasound as a diagnostic tool for acute appendicitis in the ED and the available data on diagnostic parameters such as sensitivity, specificity, and positive and negative predictive values (NPV). We constructed forest plots and summary receiver operating characteristic curves to evaluate the diagnostic accuracy of bedside ultrasound for acute appendicitis in the ED.

RESULTS

A total of 21 studies that met the inclusion criteria of this study were included for analysis. The overall pooled sensitivity was 0.81 (95% CI, 0.78-0.83), whereas the pooled specificity was 0.87 (95% CI, 0.85-0.88). However, the I2 test showed 91.7% and 90.9% heterogeneity in the sensitivity and specificity values, respectively. The summary receiver operating characteristic curves showed high levels of accuracy, as evidenced by an area under the curve of 0.9249 (standard error: 0.0180).

CONCLUSIONS

The use of ultrasound for the diagnosis of acute appendicitis in the ED showed that ultrasound has high overall sensitivity and specificity for the diagnosis of acute appendicitis. however, high heterogeneity among the included studies was observed.

A Review of Radiological Investigations in Cases of Acute Appendicitis in a Tertiary Care Hospital

INTRODUCTION

Acute appendicitis is the most common non-traumatic surgical emergency and early diagnosis and management are crucial to decrease morbidity and mortality. There is a variety of scoring systems and radiological investigations that have been used in the diagnosis of acute appendicitis. Hence, the aim of this study is to assess the diagnostic approach in patients with suspected appendicitis in a tertiary care hospital, focusing on the radiological burden.

METHODS

This is a cross-sectional study reviewing the electronic and manual medical records of all adult patients admitted with the diagnosis of acute appendicitis between January 2018 and December 2018 in Salmaniya Medical Complex, Manama, Bahrain. A review of the method of diagnosis (clinical, ultrasound, computed tomography, or others) was done, with a comparison to histopathological results in those that underwent surgical intervention to determine sensitivity and specificity.

RESULTS

In the study period, 488 patients were admitted with acute appendicitis; out of these, 461 underwent surgical intervention. A total of 66 CT scans and 148 ultrasounds were conducted for these patients, out of which 57% of ultrasounds and 86% of CT scans accurately diagnosed acute appendicitis based on histopathological diagnosis, resulting in a sensitivity of 65% and 92%, respectively, and a specificity of 56% and 25%, respectively.

CONCLUSION

The most accurate method of diagnosis of acute appendicitis (highest sensitivity) is CT scanning. However, a prospective study with a detailed assessment of complications of appendicitis is recommended.

The Efficacy of Conservative Management in Uncomplicated Acute Appendicitis - A Single-Center Retrospective Study

Background Acute appendicitis remains the most common cause of lower abdominal pain leading to emergency visits. Even though the standard treatment of acute appendicitis remains appendectomy, in recent times, multiple randomized control trials and meta-analyses have deduced conservative treatment as a successful alternative treatment. During the coronavirus disease (COVID) pandemic, with a shortage of staff and resources, treatment with conservative management of uncomplicated acute appendicitis became very beneficial under certain circumstances and conditions. This study aimed to assess whether it is effective to manage patients with uncomplicated acute appendicitis with antibiotic therapy. Methodology This was a single hospital based retrospective, cross-sectional study from Jan 2015 to May 2020. Patients with clinical and radiological features of uncomplicated acute appendicitis with Alvarado's score >6 were included in the study. Patients were kept on antibiotics, intravenous fluids, and analgesia as part of a conservative regime. Those who failed to respond to conservative therapy were managed surgically. The follow-up period was six months. Results One hundred eighty-two cases of uncomplicated acute appendicitis were included and managed conservatively, of which 52.2% were males while 47.8% were females. The median age of the patients was 26 years. Conservative treatment was successful in 26.2% of the patients, with a recurrence of 5.5% in the six-month follow-up period. The mean number of days of hospital stay was three days in patients treated with conservative or surgical treatment. Conclusion Conservative management is gaining popularity, and many centers are inclined towards non-operative management; however, appendectomy remains the gold standard treatment for appendicitis.

Diagnostic accuracy of computed tomography and ultrasound for the diagnosis of acute appendicitis: A systematic review and meta-analysis

INTRODUCTION

The diagnosis of acute appendicitis remains challenging. This review determined the current diagnostic accuracy of CT and ultrasound for suspected acute appendicitis in adults.

METHODS

This systematic review adhered to the PRISMA for diagnostic test accuracy guidelines. A systematic search was undertaken in appropriate databases. Screening of potential titles and abstracts, full-text retrieval, methodological quality assessment using QUADAS, and data extraction was performed. Meta-analyses were performed for relevant subgroups, and sensitivity analysis was completed to account for outliers. GRADE was utilized to assess the certainty of findings.

RESULTS

31 studies evaluating CT, 10 evaluating US, and six evaluating both were included. Pooled sensitivity and specificity for CT was 0.972 [0.958, 0.981] and 0.956 [0.941, 0.967] respectively, and 0.821 [0.738, 0.882] and 0.859 [0.727, 0.933] for US, respectively. When analyzing subgroups based on the use of contrast enhancement, sensitivity and specificity was highest for CT with intravenous and oral contrast (0.992 [0.965, 0.998], 0.974 [0.936, 0.99]), compared to CT with intravenous contrast (0.955 [0.922, 0.974], 0.942 [0.916, 0.960]). Low-Dose CT produced comparable values (0.934 [0.885,0.963], 0.937 [0.911, 0.955]) relative to these subgroups and standard dose non-contrast CT (0.877 [0.774,0.937], 0.914 [0.827, 0.959]). US studies which excluded equivocal findings demonstrated significantly greater values than the remainder of US studies (p < 0.0001).

CONCLUSION

The updated diagnostic test accuracies of CT, US and relevant subgroups should be implemented in light of factors such as dose, cost, and timing.

IMPLICATIONS FOR PRACTICE

For diagnosis of adult acute appendicitis: • CT with intravenous plus oral contrast enhancement yields statistically significantly greater diagnostic accuracy than CT with intravenous contrast alone. • Low-dose CT yields comparable sensitivity and specificity to standard-dose CT. • Ultrasound studies which exclude equivocal results may overinflate sensitivity and specificity.

Role of Ultrasound in the Assessment and Differential Diagnosis of Pelvic Pain in Pregnancy

Pelvic pain (PP) is common in pregnant women and can be caused by several diseases, including obstetrics, gynaecological, gastrointestinal, genitourinary, and vascular disorders. Timely and accurate diagnosis as well as prompt treatment are crucial for the well-being of the mother and foetus. However, these are very challenging. It should be considered that the physiological changes occurring during pregnancy may confuse the diagnosis. In this setting, ultrasound (US) represents the first-line imaging technique since it is readily and widely available and does not use ionizing radiations. In some cases, US may be conclusive for the diagnosis (e.g., if it detects no foetal cardiac activity in suspected spontaneous abortion; if it shows an extrauterine gestational sac in suspected ectopic pregnancy; or if it reveals a dilated, aperistaltic, and blind-ending tubular structure arising from the cecum in suspicious of acute appendicitis). Magnetic resonance imaging (MRI), overcoming some limits of US, represents the second-line imaging technique when an US is negative or inconclusive, to detect the cause of bowel obstruction, or to characterize adnexal masses.

Accuracy of imaging in discriminating complicated from uncomplicated appendicitis in daily clinical practice

BACKGROUND

Radiologic imaging can accurately diagnose acute appendicitis, but little is known about its discriminatory capacity between complicated and uncomplicated appendicitis.

OBJECTIVE

This study aims to investigate the accuracy of imaging in discriminating complicated from uncomplicated appendicitis.

METHODS

Data was used from the prospective, nationwide, observational SNAPSHOT appendicitis database, including patients with suspected acute appendicitis who were planned for an appendectomy. Usage of ultrasound (US), CT, MRI or a combination was recorded. Radiological reports were used to group for complicated or uncomplicated appendicitis. The reference standard was based on operative and pathological findings. Primary outcomes were sensitivity and specificity in discriminating complicated from uncomplicated appendicitis. Secondary outcomes were diagnostic accuracy results per imaging modality and for the subgroups age, BMI, and sex.

RESULTS

Preoperative imaging was performed in 1964 patients. In 1434 patients (73%), only US was used; in 109 (6%) patients, only CT was used; and 421 (21%) patients underwent US followed by CT or MRI. Overall, imaging workup as practiced, following the national guideline, had a poor sensitivity for complicated appendicitis of only 35%, although specificity was as high as 93%. For US, accuracy for complicated appendicitis was higher in children than in adults; sensitivity 41.2% vs. 26.4% and specificity 94.6% vs. 93.4%, respectively, p = 0.003. For relevant subgroups such as age, sex and BMI, no other differences in the discriminatory performance were found.

CONCLUSION

A diagnostic workup with stepwise imaging, using a conditional CT or MRI strategy, poorly discriminates between complicated and uncomplicated appendicitis in daily practice.

Presentation and outcomes of acute appendicitis during COVID-19 pandemic: lessons learned from the Middle East-a multicentre prospective cohort study

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic had a striking impact on healthcare services in the world. The present study aimed to investigate the impact of the COVID-19 pandemic on the presentation management and outcomes of acute appendicitis (AA) in different centers in the Middle East.

METHODS

This multicenter cohort study compared the presentation and outcomes of patients with AA who presented during the COVID-19 pandemic in comparison to patients who presented before the onset of the pandemic. Demographic data, clinical presentation, management strategy, and outcomes were prospectively collected and compared.

RESULTS

Seven hundred seventy-one patients presented with AA during the COVID pandemic versus 1174 in the pre-COVID period. Delayed and complex presentation of AA was significantly more observed during the pandemic period. Seventy-six percent of patients underwent CT scanning to confirm the diagnosis of AA during the pandemic period, compared to 62.7% in the pre-COVID period. Non-operative management (NOM) was more frequently employed in the pandemic period. Postoperative complications were higher amid the pandemic as compared to before its onset. Reoperation and readmission rates were significantly higher in the COVID period, whereas the negative appendicectomy rate was significantly lower in the pandemic period (p = 0.0001).

CONCLUSION

During the COVID-19 pandemic, a remarkable decrease in the number of patients with AA was seen along with a higher incidence of complex AA, greater use of CT scanning, and more application of NOM. The rates of postoperative complications, reoperation, and readmission were significantly higher during the COVID period.

Abbreviated MRI in patients with suspected acute appendicitis in emergency: a prospective study

PURPOSE

To determine the diagnostic performance of an abbreviated non-contrast MRI protocol in diagnosing acute appendicitis.

METHODS

Prospectively, a total of 67 consenting consecutive patients with clinical suspicion of acute appendicitis (Alvarado score ≥ 5) were evaluated with an abbreviated three-sequence non-contrast MRI protocol (axial T2WI, coronal T2WI, axial DWI) at a single tertiary care center. MRI was interpreted by two radiologists blinded to the clinical details, other investigations, and outcome of the patients. Diagnostic performance of MRI was determined using either histopathological examination (HPE) results as the reference standard in surgical cases (n = 39), or final clinical diagnosis at discharge and 3-months follow-up in non-operatively managed cases (n = 28).

RESULTS

Sixty-seven patients comprising 42 males, 25 females including 1 pregnant patient were enrolled (median age 24 years; age range 6-70 years). The median acquisition duration of the MRI protocol was 12.5 min. In the analysis of the complete cohort including both surgical and non-operatively managed cases (n = 67), MRI showed sensitivity of 93.3% (95% CI 81.7-98.6%), specificity of 86.4% (95% CI 65.1-97.1%), and diagnostic accuracy of 91.0% (95% CI 81.5-96.6%) (p < 0.001). In the subset of surgical cases with HPE as the reference standard (n = 39), MRI showed sensitivity of 97.1% (95% CI 84.7-99.9%), specificity of 100% (95% CI 47.8-100%), and diagnostic accuracy of 98% (95% CI 87.5-100%) (p < 0.001).

CONCLUSION

MRI may be performed to diagnose acute appendicitis or alternative causes of right iliac fossa pain. An abbreviated MRI protocol consisting of only three sequences without IV contrast, patient preparation, or antiperistaltic agents could shorten the examination duration while retaining diagnostic accuracy.

Abdominal Ultrasound and Its Diagnostic Accuracy in Diagnosing Acute Appendicitis: A Meta-Analysis

Background: Acute appendicitis (AA) is a common cause of abdominal pain encountering unnecessary surgeries in emergency departments. The present meta-analysis aims to assess the accuracy of abdominal ultrasound in suspected acute appendicitis cases in terms of sensitivity, specificity, and post-test odds for positive and negative results.

Materials and Methods: An extensive and systematic search was conducted in Medline (via PubMed), Cinahl (via Ebsco), Scopus, and Web of Sciences from 2010 till the end of March 2021. Two authors analyzed studies for inclusion, collected results, and conducted analyses separately. Examination of the histopathological tissue collected during appendectomy served as a gold standard for determining the final diagnosis of appendicitis. The accuracy was determined by evaluating sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), diagnostic odds ratio.

Results: Out of 3,193 references, a total of 18 studies were selected. Overall sensitivity of 77.2% (95% CI – 75.4–78.9%) and specificity of 60% (95% CI – 58–62%) were observed. The diagnostic odds ratio of 6.88(95% CI 1.99–23.82) was obtained.

Conclusion: Abdominal ultrasound shows significant accuracy of diagnosis in patients with suspected acute appendicitis.

Diagnosis of Uncomplicated and Complicated Appendicitis in Adults

Background:

Diagnostic work-up of acute appendicitis remains challenging. While some guidelines advise to use a risk stratification based on clinical parameters, others use standard imaging in all patients. As non-operative management of uncomplicated appendicitis has been identified as feasible and safe, differentiation between uncomplicated and complicated appendicitis is of paramount importance. We reviewed the literature to describe the optimal strategy for diagnosis of acute appendicitis.

Methods:

A narrative review about the diagnosis of acute appendicitis in adult patients was conducted. Both diagnostic strategies and goals were analyzed.

Results:

For diagnosing acute appendicitis, both ruling in and ruling out the disease are important. Clinical and laboratory findings individually do not suffice, but when combined in a diagnostic score, a better risk prediction can be made for having acute appendicitis. However, for accurate diagnosis imaging seems obligatory in patients suspected for acute appendicitis. Scoring systems combining clinical and imaging features may differentiate between uncomplicated and complicated appendicitis and may enable ruling out complicated appendicitis. Within conservatively treated patients with uncomplicated appendicitis, predictive factors for non-responsiveness to antibiotics and recurrence of appendicitis need to be defined in order to optimize treatment outcomes.

Conclusion:

Standard imaging increases the diagnostic power for both ruling in and ruling out acute appendicitis. Incorporating imaging features in clinical scoring models may provide better differentiation between uncomplicated and complicated appendicitis. Optimizing patient selection for antibiotic treatment of appendicitis may minimize recurrence rates, resulting in better treatment outcomes.

Validation of the Appendicitis Inflammatory Response (AIR) Score

Background

Patients with suspicion of appendicitis present with a wide range of severity. Score-based risk stratification can optimise the management of these patients. This prospective study validates the Appendicitis Inflammatory Response (AIR) score in patients with suspicion of appendicitis.

Method

Consecutive patients over the age of five with suspicion of appendicitis presenting at 25 Swedish hospital’s emergency departments were prospectively included. The diagnostic properties of the AIR score are estimated.

Results

Some 3878 patients were included, 821 with uncomplicated and 724 with complicated appendicitis, 1986 with non-specific abdominal pain and 347 with other diagnoses. The score performed better in detecting complicated appendicitis (ROC area 0.89 (95% confidence interval (CI) 0.88–0.90) versus 0.83 (CI 0.82–0.84) for any appendicitis, p < 0.001), in patients below age 15 years and in patients with >47 h duration of symptoms (ROC area 0.93, CI 0.90–0.95 for complicated and 0.87, CI 0.84–0.90 for any appendicitis in both categories). Complicated appendicitis is unlikely at AIR score <4 points (Negative Predictive Value 99%, CI 98–100%). Appendicitis is likely at AIR score >8 points, especially in young patients (positive predictive value (PPV) 96%, CI 90–100%) and men (PPV 89%, CI 84–93%).

Conclusions

The AIR score has high sensitivity for complicated appendicitis and identifies subgroups with low probability of complicated appendicitis or high probability of appendicitis. The discriminating capacity is high in children and patients with long duration of symptoms. It performs equally well in both sexes. This verifies the AIR score as a valid decision support.

Trial registration number

https://clinicaltrials.gov/ct2/show/NCT00971438

Preferred reporting items for journal and conference abstracts of systematic reviews and meta-analyses of diagnostic test accuracy studies (PRISMA-DTA for Abstracts): checklist, explanation, and elaboration

For many users of the biomedical literature, abstracts may be the only source of information about a study. Hence, abstracts should allow readers to evaluate the objectives, key design features, and main results of the study. Several evaluations have shown deficiencies in the reporting of journal and conference abstracts across study designs and research fields, including systematic reviews of diagnostic test accuracy studies. Incomplete reporting compromises the value of research to key stakeholders. The authors of this article have developed a 12 item checklist of preferred reporting items for journal and conference abstracts of systematic reviews and meta-analyses of diagnostic test accuracy studies (PRISMA-DTA for Abstracts). This article presents the checklist, examples of complete reporting, and explanations for each item of PRISMA-DTA for Abstracts.

Acute appendicitis management during the COVID-19 pandemic: A prospective cohort study from a large UK centre

BACKGROUND

During the Covid-19 pandemic, non-operative management for acute appendicitis (AA) was implemented in the UK. The aim of this study was to determine the efficacy and outcomes of conservative versus surgical management of AA during the pandemic.

MATERIALS & METHODS

We conducted an observational study in a tertiary referral centre. Data was collected from all patients (≥16 years) with a diagnosis of AA between November 1, 2019 to March 10, 2020 (pre-COVID period) and March 10, 2020 to July 5, 2020 (COVID period).

RESULTS

A total of 116 patients in the pre-COVID period were included versus 91 in the COVID period. 43.1% (n = 50) of patients pre-COVID were classified as ASA 2 compared to 26.4% (n = 24) during the COVID period (p-value = 0.042). 72.5% (n = 66) of the patients during the COVID period scored as high risk using the Alvarado score compared to 24.1% (n = 28) in the pre-COVID period (p-value<0.001). We observed a significant increase in radiological evaluation, 69.8% versus 87.5% of patients had a CT in the pre-COVID and COVID periods respectively (p-value = 0.008). 94.9% of patients were managed operatively in the pre-COVID period compared to 60.4% in the COVID period (p-value<0.001). We observed more open appendicectomies (37.3% versus 0.9%; p-value<0.001) during the COVID period compared to the pre-COVID period. More abscess formation and free fluid were found intraoperatively in the COVID period (p-value = 0.021 and 0.023 respectively). Re-attendance rate due to appendicitis-related issues was significantly higher in the COVID period (p = 0.027).

CONCLUSION

Radiological diagnosis of AA was more frequent during the COVID period. More conservative management for AA was employed during the COVID-19 pandemic, and for those managed operatively an open approach was preferred. Intra-operative findings were suggestive of delayed presentation during the COVID period without this affecting the length of hospital stay.

Barriers to reporting guideline adherence in point-of-care ultrasound research: a cross-sectional survey of authors and journal editors

OBJECTIVE

Although the literature supporting the use of point-of-care ultrasound (POCUS) continues to grow, incomplete reporting of primary diagnostic accuracy studies has previously been identified as a barrier to translating research into practice and to performing unbiased systematic reviews. This study assesses POCUS investigator and journal editor attitudes towards barriers to adhering to the Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015 guidelines.

DESIGN, SETTING, PARTICIPANTS

Two separate surveys using a 5-point Likert scale were sent to POCUS study investigators and journal editors to assess for knowledge, attitude and behavioural barriers to the complete reporting of POCUS research. Respondents were identified based on a previous study assessing STARD 2015 adherence for POCUS studies published in emergency medicine, anaesthesia and critical care journals. Responses were anonymously linked to STARD 2015 adherence data from the previous study. Written responses were thematically grouped into the following categories: knowledge, attitude and behavioural barriers to quality reporting, or other. Likert response items are reported as median with IQRs.

MAIN OUTCOME MEASURES

The primary outcome was the median Likert score for the investigator and editor surveys assessing knowledge, attitude and behavioural beliefs about barriers to adhering to the STARD 2015 guidelines.

RESULTS

The investigator survey response rate was 18/69 (26%) and the editor response rate was 5/21 (24%). Most investigator respondents were emergency medicine practitioners (13/21, 62%). Two-thirds of investigators were aware of the STARD 2015 guidelines (12/18, 67%) and overall agreed that incomplete reporting limits generalisability and the ability to detect risk of bias (median 4 (4, 5)). Investigators felt that the STARD 2015 guidelines were useful, easy to find and easy to use (median 4 (4, 4.25); median 4 (4, 4.25) and median 4 (3, 4), respectively). There was a shared opinion held by investigators and editors that the peer review process be primarily responsible for ensuring complete research reporting (median 4 (3, 4) and median 4 (3.75, 4), respectively). Three of 18 authors (17%) felt that the English publication language of STARD 2015 was a barrier to adherence.

CONCLUSIONS

Although investigators and editors recognise the importance of completely reported research, reporting quality is still a core issue for POCUS research. The shared opinion held by investigators and editors that the peer review process be primarily responsible for reporting quality is potentially problematic; we view completely reported research as an integral part of the research process that investigators are responsible for, with the peer review process serving as another additional layer of quality control. Endorsement of reporting guidelines by journals, auditing reporting guideline adherence during the peer review process and translation of STARD 2015 guidelines into additional languages may improve reporting completeness for the acute POCUS literature.

TRIAL REGISTRATION NUMBER

Open Science Framework Registry (https://osf.io/5pzxs/).

NSQIP Based Predictors of False Negative and Indeterminate Ultrasounds in Adults With Appendicitis

BACKGROUND

It has been well established that ultrasound (US) is the initial screening tool for children with suspected acute appendicitis. However, computed tomography (CT) has become the standard screening modality for adults presenting with abdominal pain. A recent review of National Surgical Quality Improvement Program (NSQIP) data revealed US is being utilized as a screening modality in adults. We aimed to assess the diagnostic performance of US in evaluating adults with acute appendicitis.

STUDY DESIGN

The American College of Surgeons NSQIP and NSQIP Procedure Targeted Data Files were accessed and examined for all patients in 2016 and 2017 who received an US and underwent an appendectomy. The US results were then correlated to the pathology in order to determine the diagnostic performance. Additionally, we identified predictors for indeterminate and false negative US results.

RESULTS

Our study included 3607 appendectomy patients of which 1135 (30%) had an indeterminate US, 683 (18%) had an US not consistent with appendicitis, and 1789 (49%) had an US consistent with appendicitis. Sensitivity and Specificity were 74.3% and 53.0%, respectively. Positive Predictive Value (PPV) and Negative Predictive Value (NPV) were 95.9% and 12.2%, respectively. On regression analysis, clinically relevant predictors for false negative and indeterminate studies included age, sex, and BMI.

CONCLUSIONS

Ultrasound is an effective initial imaging modality for acute appendicitis in the adult population. Females, age >30 y, and elevated BMI were more likely to have indeterminate or false negative results. These patients may benefit from CT as their initial screening test.

Secondary Peritonitis and Intra-Abdominal Sepsis: An Increasingly Global Disease in Search of Better Systemic Therapies

Secondary peritonitis and intra-abdominal sepsis are a global health problem. The life-threatening systemic insult that results from intra-abdominal sepsis has been extensively studied and remains somewhat poorly understood. While local surgical therapy for perforation of the abdominal viscera is an age-old therapy, systemic therapies to control the subsequent systemic inflammatory response are scarce. Advancements in critical care have led to improved outcomes in secondary peritonitis. The understanding of the effect of secondary peritonitis on the human microbiome is an evolving field and has yielded potential therapeutic targets. This review of secondary peritonitis discusses the history, classification, pathophysiology, diagnosis, treatment, and future directions of the management of secondary peritonitis. Ongoing clinical studies in the treatment of secondary peritonitis and the open abdomen are discussed.

Discriminating complicated from uncomplicated appendicitis by ultrasound imaging, computed tomography or magnetic resonance imaging: systematic review and meta-analysis of diagnostic accuracy

Background

Discriminating complicated from uncomplicated appendicitis is crucial. Patients with suspected complicated appendicitis are best treated by emergency surgery, whereas those with uncomplicated appendicitis may be treated with antibiotics alone. This study aimed to obtain summary estimates of the accuracy of ultrasound imaging, CT and MRI in discriminating complicated from uncomplicated appendicitis

Methods

A systematic literature review was conducted by an electronic search in PubMed, Embase and the Cochrane Library for studies describing the diagnostic accuracy of complicated versus uncomplicated appendicitis. Studies were included if the population comprised adults, and surgery or pathology was used as a reference standard. Risk of bias and applicability were assessed with QUADAS-2. Bivariable logitnormal random-effect models were used to estimate mean sensitivity and specificity.

Results

Two studies reporting on ultrasound imaging, 11 studies on CT, one on MRI, and one on ultrasonography with conditional CT were included. Summary estimates for sensitivity and specificity in detecting complicated appendicitis could be calculated only for CT, because of lack of data for the other imaging modalities. For CT, mean sensitivity was 78 (95 per cent c.i. 64 to 88) per cent, and mean specificity was 91 (85 to 99) per cent. At a median prevalence of 25 per cent, the positive predictive value of CT for complicated appendicitis would be 74 per cent and its negative predictive value 93 per cent.

Conclusion

Ultrasound imaging, CT and MRI have limitations in discriminating between complicated and uncomplicated appendicitis. Although CT has far from perfect sensitivity, its negative predictive value for complicated appendicitis is high.

Quality Outcomes in Appendicitis Care: Identifying Opportunities to Improve Care

INTRODUCTION

Appendicitis is one of the most common causes of acute abdominal pain requiring surgical intervention, but the variability of diagnosis and management continue to challenge the surgeons. Aim: This study assessed patients undergoing appendectomy to identify opportunities to improve diagnostic accuracy and outcomes.

METHODS

An ethically approved retrospective cohort study was undertaken between March 2016 and March 2017 at a single university hospital of all consecutive adult and paediatric patients undergoing appendectomy. Demographic data including age, gender, co-morbidities, presentation and triage timings along with investigation, imaging and operative data were analysed. Appendicitis was defined as acute based on histology coupled with intraoperative grading with the American Association for the Surgery of Trauma (AAST) grades. Complications using the Clavien-Dindo classification along with 30-day re-admission rates and the negative appendectomy rates (NAR) were recorded and categorised greater and less than 25%. The use of scoring systems was assessed, and retrospective scoring performed to compare the Alvarado, Adult Appendicitis Score (AAS) and the Appendicitis Inflammatory Response (AIR) score. Results: A total of 201 patients were studied, 115 male and 86 females, of which 136/201 (67.6%) were adults and 65/201 (32.3%) paediatric. Of the adult group, 83 were male and 53 were female, and of the paediatric group, 32 were male and 33 were female. Median age was 20 years (range: 5 years to 81 years) and no patient below the age of 5 years had an appendectomy during our study period. All patients were admitted via the emergency department and median time from triage to surgical review was 2 h and 38 min, (range: 10 min to 26 h and 10 min). Median time from emergency department review to surgical review, 55 min (range: 5 min to 6 h and 43 min). Median time to operating theatre was 21 h from admission (range: 45 min to 140 h and 30 min). Out of the total patients, 173 (86.1%) underwent laparoscopic approach, 28 (13.9%) had an open approach and 12 (6.9%) of the 173 were converted to open. Acute appendicitis occurred in 166/201 (82.6%). There was no significant association between grade of appendicitis and surgeons' categorical NAR rate (p = 0.07). Imaging was performed in 118/201 (58.7%); abdominal ultrasound (US) in 53 (26.4%), abdominal computed tomography (CT) in 59 (29.2%) and both US and CT in 6 (3%). The best cut-off point was 4 (sensitivity 84.3% and specificity of 65.7%) for AIR score, 9 (sensitivity of 74.7% and specificity of 68.6%) for AAS, and 7 (sensitivity of 77.7% and specificity of 71.4%) for the Alvarado score. Twenty-four (11.9%) were re-admitted, due to pain in 16 (58.3%), collections in 3 (25%), 1 (4.2%) wound abscess, 1 (4.2%) stump appendicitis, 1 (4.2%) small bowel obstruction and 1 (4.2%) fresh rectal bleeding. CT guided drainage was performed in 2 (8.3%). One patient had release of wound collection under general anaesthetic whereas another patient had laparoscopic drain placement. A laparotomy was undertaken in 3 (12.5%) patients with division of adhesions in 1, the appendicular stump removed in 1 and 1 had multiple collections drained.

CONCLUSION

The negative appendectomy and re-admission rates were unacceptably high and need to be reduced. Minimising surgical variance with use of scoring systems and introduction of pathways may be a strategy to reduce NAR. New systems of feedback need to be introduced to improve outcomes.

The usefulness and positive predictive value of ultrasonography and computed tomography in the diagnosis of acute appendicitis in adults: a retrospective study

OBJECTIVE

To analyze the evolution of the use of imaging tests (ultrasonography and computed tomography (CT)) in the diagnosis of acute appendicitis. To determine the positive predictive value of these tests and the percentage of negative and complicated appendectomies.

MATERIAL AND METHODS

This retrospective study compared adults who underwent appendectomy for suspected acute appendicitis at our tertiary hospital during 2015 versus similar patients at our center during 2007.

RESULTS

A total of 278 patients were included. The rate of negative appendectomies descended to 5%. The positive predictive value of ultrasonography increased to 97.4% in 2015, and the positive predictive value of CT and combined CT and ultrasonography was 100%. The rate of complicated appendicitis increased (23% in 2015).

CONCLUSIONS

The use of imaging tests increased, and the rate of "blind" laparotomies decreased. Nevertheless, the rate of complicated appendicitis increased.

Ultrasound and CT in the Diagnosis of Appendicitis: Accuracy With Consideration of Indeterminate Examinations According to STARD Guidelines

OBJECTIVE. The objective of our study was to determine the accuracy of ultrasound (US) and CT in diagnosing appendicitis at our institution while taking into account the number of indeterminate examinations in accordance with the Standards for Reporting Diagnostic Accuracy (STARD) guidelines. MATERIALS AND METHODS. We retrospectively evaluated 790 patients who underwent US, CT, or both for evaluation of suspected appendicitis between May 1, 2013, and April 30, 2015. Patient characteristics and US and CT examination results were recorded. The reference standard was histopathology or 3 months of medical record follow-up if surgery was not performed; 3 × 2 tables were generated, and sensitivity, specificity, overall test yield, and accuracy were calculated according to STARD guidelines. For surgical cases, time to surgery (one-way ANOVA) was compared among patients who underwent US alone, CT alone, or both US and CT. RESULTS. A total of 473 of 562 US examinations had indeterminate findings (overall test yield, 15.8%); sensitivity and specificity in the 89 diagnostic examinations were 98.5% and 54.2%, respectively. Thirteen of 522 CT examinations were indeterminate (overall test yield, 97.5%); sensitivity and specificity in the remaining 509 CT examinations were 98.9% and 97.2%, respectively. Taking indeterminate studies into account, the accuracy was 13.7% for US and 95.6% for CT. The negative appendectomy rates were 17.7% (11/62) for US and 3.3% (9/276) for CT (p = 0.0002). Time to surgery was longer for patients who underwent US and CT (mean ± SD, 17.7 ± 8.9 hours) than US alone (12.9 ± 6.4 hours; p = 0.002) but was not longer for patients who underwent CT alone (16.3 ± 8.4 hours; p = 0.45). CONCLUSION. At our institution, a large proportion of US examinations are indeterminate for appendicitis. CT is the preferred first-line imaging test for evaluating appendicitis in nonobstetric adult patients.

Adherence to the Standards for Reporting of Diagnostic Accuracy (STARD) 2015 Guidelines in Acute Point-of-Care Ultrasound Research

IMPORTANCE

Incomplete reporting of diagnostic accuracy research impairs assessment of risk of bias and limits generalizability. Point-of-care ultrasound has become an important diagnostic tool for acute care physicians, but studies assessing its use are of varying methodological quality.

OBJECTIVE

To assess adherence to the Standards for Reporting of Diagnostic Accuracy (STARD) 2015 guidelines in the literature on acute care point-of-care ultrasound.

EVIDENCE REVIEW

MEDLINE was searched to identify diagnostic accuracy studies assessing point-of-care ultrasound published in critical care, emergency medicine, or anesthesia journals from 2016 to 2019. Studies were evaluated for adherence to the STARD 2015 guidelines, with the following variables analyzed: journal, country, STARD citation, STARD-adopting journal, impact factor, patient population, use of supplemental material, and body region. Data analysis was performed in November 2019.

FINDINGS

Seventy-four studies were included in this systematic review for assessment. Overall adherence to STARD was moderate, with 66% (mean [SD], 19.7 [2.9] of 30 items) of STARD items reported. Items pertaining to imaging specifications, patient population, and readers of the index test were frequently reported (>66% of studies). Items pertaining to blinding of readers to clinical data and to the index or reference standard, analysis of heterogeneity, indeterminate and missing data, and time intervals between index and reference test were either moderately (33%-66%) or infrequently (<33%) reported. Studies in STARD-adopting journals (mean [SD], 20.5 [2.9] items in adopting journals vs 18.6 [2.3] items in nonadopting journals; P = .002) and studies citing STARD (mean [SD], 21.3 [0.9] items in citing studies vs 19.5 [2.9] items in nonciting studies; P = .01) reported more items. Variation by country and journal of publication were identified. No differences in STARD adherence were identified by body region imaged (mean [SD], abdominal, 20.0 [2.5] items; head and neck, 17.8 [1.6] items; musculoskeletal, 19.2 [3.1] items; thoracic, 20.2 [2.8] items; and other or procedural, 19.8 [2.7] items; P = .29), study design (mean [SD], prospective, 19.7 [2.9] items; retrospective, 19.7 [1.8] items; P > .99), patient population (mean [SD], pediatric, 20.0 [3.1] items; adult, 20.2 [2.7] items; mixed, 17.9 [1.9] items; P = .09), use of supplementary materials (mean [SD], yes, 19.2 [3.0] items; no, 19.7 [2.8] items; P = .91), or journal impact factor (mean [SD], higher impact factor, 20.3 [3.1] items; lower impact factor, 19.1 [2.4] items; P = .08).

CONCLUSIONS AND RELEVANCE

Overall, the literature on acute care point-of-care ultrasound showed moderate adherence to the STARD 2015 guidelines, with more complete reporting found in studies citing STARD and those published in STARD-adopting journals. This study has established a current baseline for reporting; however, future studies are required to understand barriers to complete reporting and to develop strategies to mitigate them.

Randomized control trial comparing an Alvarado Score-based management algorithm and current best practice in the evaluation of suspected appendicitis

BACKGROUND

An objective algorithm for the management of suspected appendicitis guided by the Alvarado Score had previously been proposed. This algorithm was expected to reduce computed tomography (CT) utilization without compromising the negative appendectomy rate. This study attempts to validate the proposed algorithm in a randomized control trial.

METHODS

A randomized control trial comparing the management of suspected acute appendicitis using the proposed algorithm compared to current best practice, with the rate of CT utilization as the primary outcome of interest. Secondary outcomes included the percentage of missed diagnosis, negative appendectomies, length of stay in days, and overall cost of stay in dollars.

RESULTS

One hundred sixty patients were randomized. Characteristics such as age, ethnic group, American Society of Anesthesiologist score, white cell count, and symptom duration were similar between the two groups. The overall CT utilization rate of the intervention arm and the usual care arm were similar (93.7% vs 92.5%, p = 0.999). There were no differences in terms of negative appendectomy rate, length of stay, and cost of stay between the intervention arm as compared to the usual care arm (p = 0.926, p = 0.705, and p = 0.886, respectively). Among patients evaluated with CT, 75% (112 out of 149) revealed diagnoses for the presenting symptoms.

CONCLUSION

The proposed AS-based management algorithm did not reduce the CT utilization rate. Outcomes such as missed diagnoses, negative appendectomy rates, length of stay, and cost of stay were also largely similar. CT utilization was prevalent as 93% of the study cohort was evaluated by CT scan.

TRIAL REGISTRATION

The study has been registered at ClinicalTrials.gov (NCT03324165, Registered October 27 2017).

Factors Influencing the Result of Sonographic Diagnosis of Acute Appendicitis in a Large Hospital in the Netherlands

Objective:

Appendicitis is a common surgical emergency, for which sonography is widely used to assess the presence of absence of appendicitis. The objective of this study was to identify factors associated with the diagnostic accuracy of sonography in patients with a suspected case of acute appendicitis.

Methods:

A retrospective review was conducted in all patients who were assessed for acute appendicitis (with sonography) in two emergency rooms of a large hospital. The sonography result was compared with the pathological report in patients who underwent surgery under suspicion of an acute appendicitis.

Results:

A multivariate analysis revealed that operator (radiologist or resident), time of the sonogram, site (hospital), and body mass index were independent variables significantly influencing the sonographic result. Correctly diagnosing suspected appendicitis with sonography is 2.2 times more likely when performed by a radiologist compared to a resident.

Conclusions:

Sonography is widely used in diagnosing appendicitis in the emergency room. In this study, the probability of sonography being correctly diagnosed decreases during on-call hours or when conducted by a resident in patients with suspected appendicitis. Furthermore, increasing body mass index decreases the probability of a sonogram being correct when conducted by a resident compared to a radiologist.

Appendiceal Crohn's disease: a rare differential of right iliac fossa pain

A 30-year-old man with a history of severe right iliac fossa pain was referred to the surgical emergency unit. His symptoms began 3 days prior as mild, non-specific abdominal pain which progressively localised to the right iliac fossa and worsened in severity. Investigations were suggestive of acute appendicitis, and therefore a laparoscopic appendicectomy was planned. Laparoscopy revealed a thickened, necrotic appendix with a mass at the base of the appendix, in keeping with the appearance of an appendiceal malignancy. Subsequently a right hemicolectomy was performed. Histology revealed active chronic inflammation and granulomas highly suggestive of appendiceal Crohn's disease. Since, the patient has made a good recovery and presently shows no further signs of Crohn's disease. This case is demonstrative of one of many rare findings on histological examination of the appendix. It emphasises the need for a wide differential when investigating right iliac fossa pain.

Accuracy of ultrasound exam performed by emergency medicine versus radiology residents in the diagnosis of acute appendicitis

BACKGROUND

Although the traditional approach to the diagnosis of acute appendicitis (AA) is using clinical methods, experience has shown that strict reliance on clinical data can lead to mismanagement or unnecessary surgery.

OBJECTIVE

The objective of this study was to determine the total agreement of ultrasound (US) results in AA performed by emergency medicine (EM) versus radiology residents in emergency department.

PATIENTS AND METHODS

In this cross-sectional study, 121 patients with AA suspicion underwent an US exam by both trained EM and radiology residents in emergency department. The training course for EM residents consisted of attending an 8-h-workshop and then practicing an US exam on real patients within a 2-month period. The gold standards were either histopathologic or follow-up results. Total agreement of the results in both specialties was compared.

RESULTS

There were 67 men and 54 women, with a mean age of 33.6 ± 16.1 years (18.2-88.7 years). Fifty-four (44.6%) patients underwent surgery with the initial diagnosis of AA and the rest were evaluated by follow-ups. On the basis of our gold standards, the diagnosis was finally confirmed in 46 (38%) cases. There was a high total agreement in AA diagnosis [96% agreement, κ = 0.90; 95% confidence interval (CI) = 0.81-0.99] between the two groups. The specificity and sensitivity of EM and radiology groups were 99% (95% CI = 93-100), 63% (95% CI = 48-77), 97% (95% CI = 91-100), and 72% (95% CI = 57-84), respectively.

CONCLUSION

US has a high diagnostic specificity in patients suspected of having AA and EM residents can perform this modality as accurately as radiologists after training in the emergency setting.

[Rational diagnostics of acute appendicitis]

Acute appendicitis is one of the most common abdominal emergencies. An accurate preoperative diagnosis is still a challenge in many cases. Patient history and clinical examination are the mainstay of diagnostics but other tools are also needed in order to reduce the number of misdiagnoses. Laboratory parameters and radiological imaging procedures are widely used and scoring systems can help in the risk stratification of patients with suspected appendicitis. In the USA most patients undergo preoperative computed tomography (CT) as the first-line examination, which can reduce the number of negative appendectomies to less than 5%; however, this practice results in substantial radiation exposure and is less accepted in Europe due to concerns about radiation-induced cancer in the often younger patients. Ultrasound is a valuable first-line imaging procedure and in experienced hands can achieve very good results. In patients with an equivocal diagnosis inpatient surveillance with close control of clinical and laboratory parameter represents a suitable method to reduce the number of negative explorations without resulting in an increase in the rate of perforation or morbidity.

Diagnostic yield of abdominal ultrasonography for the diagnosis of acute appendicitis: A global and subgroup analysis

INTRODUCTION AND AIMS

Abdominal ultrasonography is very useful for diagnosing acute appendicitis and has 59-96% sensitivity and 83-98% specificity. The aim of the present study was to determine the diagnostic yield of abdominal ultrasound imaging for acute appendicitis and identify the patient subgroups with the best results.

MATERIALS AND METHODS

Patients at a general hospital that underwent appendectomy due to the clinical suspicion of appendicitis, who also had a diagnostic radiologic study, within the time frame of January 2007 to December 2010, were analyzed. Ultrasound studies were considered positive when there were radiologic signs suggestive of acute appendicitis. The sensitivity, specificity, and predictive values of the diagnostic study were determined through the logistic regression method.

RESULTS

A total of 646 patients were operated on due to clinical suspicion of acute appendicitis. A diagnostic abdominal ultrasound study was carried out on 383 (59.3%) of those patients, resulting in 79% sensitivity (74-83, 95% CI), 58% specificity (39-75, 95% CI), 95% positive predictive value (92-97, 95% CI), and 20% negative predictive value (13-30, 95% CI).

CONCLUSIONS

Abdominal ultrasound imaging in patients with a high suspicion of appendicitis had a mediocre diagnostic yield, but better results could be achieved in different specific subgroups.

Diagnostic performance of emergency physician-performed point-of-care ultrasonography for acute appendicitis: A meta-analysis

OBJECTIVE

To assess the sensitivity and specificity of emergency physician-performed point-of-care ultrasonography (EP-POCUS) for diagnosing acute appendicitis (AA).

MATERIAL AND METHODS

The PubMed and EMBASE databases were searched, and the diagnostic performance of EP-POCUS was evaluated using bivariate modeling and hierarchical summary receiver operating characteristic curves. Subgroup analysis was performed for pediatric patients to compare EP-POCUS and radiologist-performed ultrasonography (RADUS). Meta-regression analyses were performed according to patient and study characteristics.

RESULTS

In 17 studies (2385 patients), EP-POCUS for diagnosing AA exhibited a pooled sensitivity of 84% (95% confidence interval [CI]: 72%-92%) and a pooled specificity of 91% (95% CI: 85%-95%), with even better diagnostic performance for pediatric AA (sensitivity: 95%, 95% CI: 75%-99%; specificity: 95%, 95% CI: 85%-98%). A direct comparison revealed no significant differences (p = 0.18-0.85) between the diagnostic performances of EP-POCUS (sensitivity: 81%, 95% CI: 61%-90%; specificity: 89%, 95% CI: 77%-95%) and RADUS (sensitivity: 74%, 95% CI: 65%-81%; specificity: 97%, 95% CI: 93%-98%). The meta-regression analyses revealed that study location, AA proportion, and mean age were sources of heterogeneity. Higher sensitivity and specificity tended to be associated with an appendix diameter cut-off value of 7 mm and the EP as the initial operator.

CONCLUSION

The diagnostic performances of EP-POCUS and RADUS were excellent for AA, with EP-POCUS having even better performance for pediatric AA. Accurate diagnoses may be achieved when the attending EP is the initial POCUS operator and uses a 7-mm cut-off value.

Accuracy of Point-of-care Ultrasonography for Diagnosing Acute Appendicitis: A Systematic Review and Meta-analysis

BACKGROUND

The use of ultrasonography (US) to diagnose appendicitis is well established. More recently, point-of-care ultrasonography (POCUS) has also been studied for the diagnosis of appendicitis, which may also prove a valuable diagnostic tool. The purpose of this study was through systematic review and meta-analysis to identify the test characteristics of POCUS, specifically US performed by a nonradiologist physician, in accurately diagnosing acute appendicitis in patients of any age.

METHODS

We conducted a thorough and systematic literature search of English language articles published on point-of-care, physician-performed transabdominal US used for the diagnosis of acute appendicitis from 1980 to May, 2015 using OVID MEDLINE In-Process & Other Non-indexed Citations and Scopus. Studies were selected and subsequently independently abstracted by two trained reviewers. A random-effects pooled analysis was used to construct a hierarchical summary receiver operator characteristic curve, and a meta-regression was performed. Quality of studies was assessed using the QUADAS-2 tool.

RESULTS

Our search yielded 5,792 unique studies and we included 21 of these in our final review. Prevalence of disease in this study was 29.8%, (range = 6.4%-75.4%). The sensitivity and specificity for POCUS in diagnosing appendicitis were 91% (95% confidence interval [CI] = 83%-96%) and 97% (95% CI = 91%-99%), respectively. The positive and negative predictive values were 91 and 94%, respectively. Studies performed by emergency physicians had slightly lower test characteristics (sensitivity = 80%, specificity = 92%). There was significant heterogeneity between studies (I² = 99%, 95% CI = 99%-100%) and the quality of the reported studies was moderate, mostly due to unclear reporting of blinding of physicians and timing of scanning and patient enrollment. Several of the studies were performed by a single operator, and the education and training of the operators were variably reported.

CONCLUSION

Point-of-care US has relatively high sensitivity and specificity for diagnosing acute appendicitis, although the data presented are limited by the quality of the original studies and large CIs. In the hands of an experienced operator, POCUS is an appropriate initial imaging modality for diagnosing appendicitis. Based on our results, it is premature to utilize POCUS as a stand-alone test or to rule out appendicitis.