Appendicitis In Adults Research Articles

Predictive model for identification of gangrenous or perforated appendicitis in adults: a multicenter retrospective study

BackgroundGangrene and perforation are severe complications of acute appendicitis, associated with a higher mortality rate compared to uncomplicated appendicitis. Accurate preoperative identification of Gangrenous or perforated appendicitis (GPA) is crucial for timely surgical intervention.MethodsThis retrospective multicenter study includes 796 patients who underwent appendectomy. Univariate and multivariate logistic regression analyses are used to develop a nomogram model for predicting GPA based on laboratory tests and computed tomography (CT) findings. The model is validated using an external dataset.ResultsSeven independent predictors were included in the nomogram: white blood cell count, lymphocyte count, D-dimer, serum glucose, albumin, maximum outer diameter of the appendix, and presence of appendiceal fecalith. The nomogram achieved good discrimination and calibration in both the training and testing sets. In the training set, the AUC was 0.806 (95%CI: 0.763–0.849), and the sensitivity and specificity were 82.1% and 66.9%, respectively. The Hosmer-Lemeshow test showed good calibration (P = 0.7378). In the testing set, the AUC was 0.799 (95%CI: 0.741–0.856), and the sensitivity and specificity were 70.5% and 75.3%, respectively. Decision curve analysis (DCA) confirmed the clinical utility of the nomogram.ConclusionThe laboratory test-CT nomogram model can effectively identify GPA patients, aiding in surgical decision-making and improving patient outcomes.

Efficacy of automated machine learning models and feature engineering for diagnosis of equivocal appendicitis using clinical and computed tomography findings

This study evaluates the diagnostic efficacy of automated machine learning (AutoGluon) with automated feature engineering and selection (autofeat), focusing on clinical manifestations, and a model integrating both clinical manifestations and CT findings in adult patients with ambiguous computed tomography (CT) results for acute appendicitis (AA). This evaluation was compared with conventional single machine learning models such as logistic regression(LR) and established scoring systems such as the Adult Appendicitis Score(AAS) to address the gap in diagnostic approaches for uncertain AA cases. In this retrospective analysis of 303 adult patients with indeterminate CT findings, the cohort was divided into appendicitis (n = 115) and non-appendicitis (n = 188) groups. AutoGluon and autofeat were used for AA prediction. The AutoGluon-clinical model relied solely on clinical data, whereas the AutoGluon-clinical-CT model included both clinical and CT data. The area under the receiver operating characteristic curve (AUROC) and other metrics for the test dataset, namely accuracy, sensitivity, specificity, PPV, NPV, and F1 score, were used to compare AutoGluon models with single machine learning models and the AAS. The single ML models in this study were LR, LASSO regression, ridge regression, support vector machine, decision tree, random forest, and extreme gradient boosting. Feature importance values were extracted using the “feature_importance” attribute from AutoGluon. The AutoGluon-clinical model demonstrated an AUROC of 0.785 (95% CI 0.691–0.890), and the ridge regression model with only clinical data revealed an AUROC of 0.755 (95% CI 0.649–0.861). The AutoGluon-clinical-CT model (AUROC 0.886 with 95% CI 0.820–0.951) performed better than the ridge model using clinical and CT data (AUROC 0.852 with 95% CI 0.774–0.930, p = 0.029). A new feature, exp(-(duration from pain to CT)3 + rebound tenderness), was identified (importance = 0.049, p = 0.001). AutoML (AutoGluon) and autoFE (autofeat) enhanced the diagnosis of uncertain AA cases, particularly when combining CT and clinical findings. This study suggests the potential of integrating AutoML and autoFE in clinical settings to improve diagnostic strategies and patient outcomes and make more efficient use of healthcare resources. Moreover, this research supports further exploration of machine learning in diagnostic processes.

Predictors of appendicectomy one year after antibiotic treatment for acute appendicitis: Insights from a prospective, multicentre, observational study.

Surgeons are sometimes reluctant to manage uncomplicated appendicitis non-operatively. Reasons cited include the risk of recurrent appendicitis and the risk of missed appendiceal malignancy. The aim of this study was to address these uncertainties and determine the long-term efficacy of antibiotic versus operative management of appendicitis. One-year follow-up of patients enrolled in the multicentre, COVID:HAREM cohort study during March-June 2020 was performed. Initial operative or non-operative management was determined on a case-by-case basis by the responsible surgeon. Outcomes were appendicectomy rate at 1-year, histology of removed appendix and predictors of unsuccessful antibiotic treatment. A total of 625 patients who had non-operative management were included. Emergency appendicectomy had been performed by 1-year in 24% (149/625), with a median time to appendicectomy of 12days [IQR 1-77] from presentation. Thirty-one patients had elective appendicectomy. Normal histology was reported in 6% of emergency procedures and 58% of elective ones. There were 7 malignancies and 3 neuroendocrine tumors identified at histology. All patients with malignant histology had ≥1 risk factors for malignancy at initial presentation. Faecolithiasis (hazard ratios (HR) 2.3, 95% confidence intervals (CI) 1.51-3.49) and a high Adult Appendicitis Score (AAS >16; HR 2.44, 95% CI 1.52-3.92) were independent risk factors for unsuccessful non-operative management. At 1year, 71% of patients managed non-operatively did not undergo an appendicectomy. Recurrence of appendicitis was associated with faecolithiasis and a high AAS. Patients at higher risk for appendiceal malignancy should have targeted follow-up. These factors should be considered when counseling patients on non-operative management.

Nationwide prospective audit for the evaluation of appendicitis risk prediction models in adults: right iliac fossa treatment (RIFT)-Turkey.

Appendicitis is the most prevalent surgical emergency. The negative appendicectomy rate and diagnostic uncertainty are important concerns. This study aimed to assess the effectiveness of current appendicitis risk prediction models in patients with acute right iliac fossa pain. A nationwide prospective observational study was conducted, including all consecutive adult patients who presented with right iliac fossa pain. Diagnostic, clinical and negative appendicectomy rate data were recorded. The Alvarado score, Appendicitis Inflammatory Response (AIR), Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) and Adult Appendicitis Score systems were calculated with collected data to classify patients into risk categories. Diagnostic value and categorization performance were evaluated, with use of risk category-based metrics including 'true positive rate' (percentage of appendicitis patients in the highest risk category), 'failure rate' (percentage of patients with appendicitis in the lowest risk category) and 'categorization resolution' (true positive rate/failure rate). A total of 3358 patients from 84 centres were included. Female patients were less likely to undergo surgery than men (71.5% versus 82.5% respectively; relative risk 0.866, 95% c.i. 0.834 to 0.901, P < 0.001); with a three-fold higher negative appendicectomy rate (11.3% versus 4.1% respectively; relative risk 2.744, 95% c.i. 2.047 to 3.677, P < 0.001). Ultrasonography was utilized in 56.8% and computed tomography in 75.2% of all patients. The Adult Appendicitis Score had the best diagnostic performance for the whole population; however, only RIPASA was significant in men. All scoring systems were successful in females patients, but Adult Appendicitis Score had the highest area under the receiver operating characteristic curve value. The RIPASA and the Adult Appendicitis Score had the best categorization resolution values, complemented by their exceedingly low failure rates in both male and female patients. Alvarado and AIR had extremely high failure rates in men. The negative appendicectomy rate was low overall, but women had an almost three-fold higher negative appendicectomy rate despite lower likelihood to undergo surgery. The overuse of imaging tests, best exemplified by the 75.2% frequency of patients undergoing computed tomography, may lead to increased costs. Risk-scoring systems such as RIPASA and Adult Appendicitis Score appear to be superior to Alvarado and AIR.

Outcomes Following Surgical and Nonsurgical Treatment for Uncomplicated Appendicitis in Older Adults

The optimal treatment of acute uncomplicated appendicitis in older adults with frailty is not defined. To examine outcomes associated with treatment strategies for acute uncomplicated appendicitis in older adults with or without frailty. This retrospective cohort study used National Inpatient Sample data from adults 65 years or older with a diagnosis of uncomplicated appendicitis from January 1, 2016, to December 31, 2018. Data were analyzed from July to November 2023. The National Inpatient Sample database approximates a 20% stratified sample of all inpatient hospital discharges in the US. Study patients were categorized into 3 groups: nonoperative management, immediate operation, and delayed operation. Clinical outcomes, including hospital complications and in-hospital mortality, were assessed among older adults with and without frailty, identified using an adapted claims-based frailty index. A total of 24 320 patients were identified (median [IQR] age, 72 [68-79] years; 50.9% female). Of those, 7290 (30.0%) were categorized as having frailty. Overall, in-hospital mortality was 1.4%, and the incidence of complications was 37.3%. In patients with frailty, multivariable analysis showed both nonoperative management (odds ratio [OR], 2.89; 95% CI, 1.40-5.98; P < .001) and delayed appendectomy (OR, 3.80; 95% CI, 1.72-8.43; P < .001) were associated with increased in-hospital mortality compared with immediate appendectomy. In patients without frailty, immediate appendectomy was associated with increased hospital complications compared with nonoperative management (OR, 0.77; 95% CI, 0.64-0.94; P = .009) and lower hospital complications compared with delayed appendectomy (OR, 2.05; 95% CI, 1.41-3.00; P < .001). In this cohort study of older adults with uncomplicated appendicitis, outcomes differed among management strategies based on frailty status. Routine frailty assessments incorporated in the care of older adult patients may help guide discussions for shared decision-making.

The contemporary management of perforated appendicitis in adults: To operate or wait?

ObjectivesThe optimal management of perforated appendicitis remains controversial. Many studies advocate for antibiotics and an interval appendectomy whereas others suggest that performing an appendectomy at the time of presentation decreases post-operative morbidity. Confounding this argument further are the patients who fail non-operative management and end up requiring surgery during their initial hospitalization. This study aims to determine if early operative intervention should be considered for perforated appendicitis. MethodsThis was a retrospective review of all patients who underwent an appendectomy (both laparoscopic or open) for perforated appendicitis between 2015 and 2020 at our institution. ResultsA total of 271 patients met inclusion criteria for this study. Of this group, 250 patients underwent an immediate appendectomy whereas the remaining 21 patients underwent a trial of non-operative management and eventually required an appendectomy during their initial admission. When comparing the immediate versus delayed operative groups, there were no differences in demographic data including age and gender, and no differences in various imaging findings including AAST Grade IV or V appendicitis. Operatively, patients in the delayed group had a longer operative time (83.1 ± 32.9 vs. 64.1 ± 26.2, p = 0.01), were more likely to require an open operation (23.8 % vs. 2.8 %, p < 0.0001), and were more likely to have a drain placed intra-operatively (42.9 % vs 14.4 %, p = 0.004). While there were no differences in 30-day readmission rates, patients in the delayed group had a significantly longer hospital length of stay than patients in the immediate group (9.4 ± 7.4 vs. 3.1 ± 3.3, p = 0.008). ConclusionsPatients undergoing an immediate appendectomy for perforated appendicitis can discharge from the hospital sooner and demonstrate no increase in post-operative morbidity suggesting that surgeons can initially manage this disease process in an operative fashion.

2024 Clinical Practice Guideline Update by the Infectious Diseases Society of America on Complicated Intra-abdominal Infections: Diagnostic Imaging of Suspected Acute Appendicitis in Adults, Children, and Pregnant People.

This paper is part of a clinical practice guideline update on the risk assessment, diagnostic imaging, and microbiological evaluation of complicated intra-abdominal infections in adults, children, and pregnant people, developed by the Infectious Diseases Society of America (IDSA). In this paper, the panel provides recommendations for diagnostic imaging of suspected acute appendicitis. The panel's recommendations are based on evidence derived from systematic literature reviews and adhere to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach.

Prediction of the outcome of nonoperative management of uncomplicated acute appendicitis in adults

Prediction of the outcome of nonoperative management of uncomplicated acute appendicitis in adults

Accuracy of Surgeon’s Clinical Acumen in Diagnosing Severity of Appendicitis in Adults

Accuracy of Surgeon’s Clinical Acumen in Diagnosing Severity of Appendicitis in Adults

Incomplete Common Mesentery Revealed by Appendicitis in Adults: A Case Report

Incomplete Common Mesentery Revealed by Appendicitis in Adults: A Case Report

Complicated Appendicitis: An Update on Management: Mini Review

Complicated appendicitis is a complication of acute appendicitis, which is defined as perforation of the appendix, with abscess or mass formation. The management of complicated appendicitis was initially with conservative treatment with intra-venous antibiotics, with percutaneous drainage of abscess reserved for patients with abscess formation. The recent trend has seen a movement towards immediate appendectomy with laparoscopic appendectomy being the preferred surgical option. As there is no definitive consensus on the management of complicated appendicitis, we have conducted this mini review to look at the treatment option for complicated appendicitis in adults and children.

Interhospital variation in the non-operative management of uncomplicated appendicitis in adults

BackgroundRecent randomized trials have suggested non-operative management to be a safe alternative to appendectomy for acute uncomplicated appendicitis. Yet, there remains significant variability in treatment approach. This study sought to characterize center-level variation in non-operative management within a national cohort of adults presenting with appendicitis. MethodsThe 2016–2020 Nationwide Readmissions Database was queried to identify all adult (≥18 years) hospitalizations for acute uncomplicated appendicitis. Hierarchical, mixed-effects models were developed to ascertain factors linked with non-operative management. Bayesian methodology was applied to predict random effects, which were then used to rank centers by increasing hospital-attributed rate of non-operative management. Institutions with high center-specific rates of non-operative management (>90th percentile) were considered low-operating hospitals (LOH). ResultsOf an estimated 447,500 patients, 52,523 (11.7 %) were managed non-operatively. Compared to those undergoing appendectomy, the non-operative cohort was older, more commonly male, and of a higher comorbidity burden. Approximately 30 % in the variability of non-operative management was attributable to hospital effects, with absolute, risk-adjusted rates ranging from 0.5 to 22.5 %. Centers with non-operative management rates ≥90th percentile were considered LOH.Following risk adjustment, among patients undergoing appendectomy, care at LOH was linked with greater odds of postoperative infection, resource utilization, and non-elective readmission. ConclusionsWe identified significant interhospital variation in the utilization of non-operative management for acute uncomplicated appendicitis. Further, we found LOH to be associated with inferior outcomes following surgical management. Future work is needed to assess the care pathways that contribute to increased utilization of non-operative strategies, and disseminate best practices across institutions.

The impact of surgical timing on outcome in acute appendicitis in adults: a retrospective observational population-based cohort study.

Acute appendicitis is a global disease with high incidence. The main objective was to assess the association between time from admission to surgery (TAS) and surgery during emergency hours with operative outcome in light of conflicting evidence. This is a retrospective population-wide analysis of hospital billing data (2010-2021) of all adult patient records of surgically treated cases of acute appendicitis in Germany by TAS. The primary outcome was a composite clinical endpoint (CCE; prolonged length of stay, surgical site infection, interventional draining after surgery, revision surgery, ICU admission and/or in-hospital mortality). Cases of complicated appendicitis were identified using diagnosis (ICD-10) and procedural codes (resection beyond appendectomy). 855694 patient records were included, of which 27·6% (236,481) were complicated cases of acute appendicitis. 49·0% (418,821) were females and median age was 37 (interquartile range 22·5-51·5). Age, male sex, and comorbidity were associated with an increased proportion of CCE and in-hospital mortality. TAS was associated with a clinically relevant increase of CCE after 12h in complicated appendicitis [Odd's ratio (OR), 1·19, 95% CI: 1·14-1·21] and after 24h in uncomplicated appendicitis (OR 1·10, 95% CI: 1·02-1·19). Beyond the primary endpoint, the proportion of complicated appendicitis increased after TAS of 72h. Surgery during emergency hours (6 pm-6.59 am) was associated with an increase of CCE and mortality (OR between 1·14 and 1·49). Age, female sex, night-time admission, weekend admission, a known previous surgery, obesity, and therapeutic anticoagulation were associated with delayed performance of surgery. This work found an increase of a CCE after TAS of 12h for complicated appendicitis and an increase of the CCE after TAS of 24h for uncomplicated appendicitis with a stable proportion of complicated appendicitis in these time windows. Both CCE and mortality were increased if appendectomy was performed during emergency hours.

Acute appendicitis in adults: only clinical and laboratory diagnostics, only imaging, or both?

The presented article is devoted to the discussion of the necessity and expediency of using medical visualization diagnostics — radiological imaging — of acute appendicitis as an independent or complex approach in combination with clinical and laboratory data. Until now, the clinical diagnosis of each individual case of acute appendicitis is complicated, and its formulation requires combining clinical, laboratory and imaging data, since it includes a wide range of differential diagnoses depending on age and gender. The literature provides data that the frequency of negative appendectomies based on the results of a clinical examination can be up to 28.2%. Radiological imaging is used as an adjunct to clinical diagnostics using ultrasound examination, computed tomography and magnetic resonance imaging, but the role of the latter is limited by the duration of the study, increased cost, unavailability around the clock, as well as the presence of absolute contraindications. Sonography and computed tomography in diagnostics have a number of advantages and disadvantages, and the question of choosing a specific method still causes scientific controversy. We also provide illustrative clinical examples demonstrating echographic and computed tomographic imaging manifestations of acute appendicitis, as well as discuss visualization signs. For a patient with suspected acute appendicitis, in order to increase the accuracy of diagnosis, reduce complications or the need of undergoing unnecessary diagnostic and therapeutic procedures, a multidisciplinary and multimodal approach is necessary, taking into account age, gender and constitution, however, the question of choosing the optimal method of medical imaging in the diagnosis of acute appendicitis between ultrasound and computed tomography remains debatable.

Impact of COVID-19 on acute appendicitis presentation, management and pathology findings in adult and paediatric populations.

We investigated the impact of the COVID-19 pandemic on trends of presentation, management and pathology findings in patients who underwent an appendicectomy for suspected acute appendicitis. The retrospective study reviewed patients (n = 939 adults and n = 329 children) who had an appendicectomy performed for suspected acute appendicitis and histopathology assessment in the Belfast Health and Social Care Trust, Northern Ireland. Pre-COVID-19 (March 2019 to February 2020) and COVID-19 Year 1 (March 2020 to February 2021) data were compared. Chi-squared tests were applied to compare timeframes. 513 adult appendicectomies were performed in the immediate year pre-COVID-19, compared to 426 in COVID-19 Year 1, representing a 17% reduction. No such reduction was seen within the paediatric population, likely related to a change in regional paediatric referral criteria during the pandemic. When comparing COVID-19 Year 1 with pre-pandemic, fewer patients presented with <24 hours of symptoms (45% v 53%, p = 0.005), and there was greater use of pre-operative computed tomography imaging in adults (63.2% v 48.7%, p<0.001). Fewer adult and paediatric cases of simple acute appendicitis and non-diagnostic specimens, with relative increased proportions of perforated acute appendicitis, were observed in COVID-19 Year 1 compared with pre-pandemic. No absolute increase in perforated acute appendicitis cases was observed in adults. Year 1 of the COVID-19 pandemic was associated with delayed presentation of acute appendicitis in adults and children. In adults, an overall reduction in appendicectomy operations, increased use of pre-operative diagnostic imaging, and fewer specimens showing simple acute appendicitis or non-diagnostic features, collectively support appropriate restriction of surgery for those patients with a more certain acute appendicitis diagnosis.

Evaluation of clinical examination and preoperative imaging in patients with right iliac fossa pain and a medium or high risk score for appendicitis (RIFT-2)

Introduction: Clinical risk models can be used to safely stratify UK patients with suspected appendicitis with low scores to ambulatory pathways, preventing admissions and unnecessary surgery. This study aimed to examine the diagnostic pathways in patients with medium or high risk scores.&#x0D; Methods: This prospective cohort study included patients admitted with suspected appendicitis in the UK. Patients aged ≥16 years were included if they had a medium or high risk score for appendicitis (Appendicitis Inflammatory Response score &gt;2 in men, Adult Appendicitis Score &gt;8 in women). The primary outcome measure was the normal appendicectomy rate (NAR). The AIRS and AAS risk prediction models were validated against pre-determined criteria.&#x0D; Results: This UK study included 2,231 women and 1,958 men. Overall, 57.7% of patients underwent surgery. The NAR was 18.4% in women aged 16-45 years, 9.5% in men aged 16-45 years, 4.5% in women aged ≥46 years, and 2.1% in men aged ≥46 years. Risk prediction models did not achieve the pre-determined threshold to be used to identify patients with appendicitis. Ultrasound was the most common imaging modality in women aged 16-45 years, whereas CT was most common in the other subgroups. CT was performed in 12.8% women aged 16-45 years, 21.1% in men aged 16-45 years, 69.3% in women aged ≥46 years, and 74.5% in men aged ≥46 years. The overall NAR in patients who had CT imaging alone (3.6%) was lower than in patients who had no imaging (12.4%) or ultrasound imaging alone (19.0%).&#x0D; Conclusion: Patients with right iliac fossa pain should be risk scored, with low-risk patients triaged to ambulatory management and medium and high-risk patients routinely CT scanned. Normal appendicectomy should become a specific therapeutic option rather than a chance finding.

State of the Art Review: Evidence based management of acute appendicitis

Introduction: Even though acute appendicitis is the world’s most common emergency general surgical operation, it remains under-researcher with wide variations in care. The aim of this review was to present current evidence on the management of acute appendicitis, focusing on risk assessment, diagnostic modalities, treatment strategies, and special considerations for specific patient populations.&#x0D; &#x0D; Methods: The writing group conducted a modified Delphi to prioritise topic areas for inclusion in this review. Consensus was achieved when each topic had &gt;70% for either important or strongly important. Scoping reviews of current and grey literature were conducted to identify relevant evidence, focussing on new publications in the last 5 years (2019-2024).&#x0D; &#x0D; Results: Validated risk scoring systems, such as the Adult Appendicitis Score and the AIRS score, aid in identifying low-risk patients suitable for ambulatory management, while imaging modalities, including CT scans and ultrasound, play a pivotal role in confirming diagnosis and guiding treatment decisions. The review highlights the efficacy of surgical intervention versus antibiotic therapy, emphasising the importance of shared decision-making and individualised treatment plans. Tailored care strategies are needed for elderly patients, pregnant women, and those with appendiceal neoplasms whilst strategies for optimising antibiotic stewardship, minimising negative appendectomy rates, and enhancing postoperative care will provide the best evidence-based care.&#x0D; &#x0D; Discussion: This review provides evidence-based practices can be integrated into routine clinical care and ongoing education for frontline clinicians. The practice recommendations are designed to be evidence based and can be tailored depending on local resources. These should form the basis of future educational packages and surgical training programmes.&#x0D;

The risks of failed nonoperative management of appendicitis in older adults

BackgroundThe consequences of failed nonoperative management of appendicitis in older patients have not been described. MethodsWe used the 2004–2017 National Inpatient Sample to identify acute appendicitis patients managed nonoperatively (<65 years old: 32,469; ≥65 years old: 11,265). Outcomes included morbidity, length of stay (LOS), inpatient costs, and discharge to skilled facilities. Differences were estimated using propensity scores. ResultsFor patients <65, nonoperative failure was associated with increased morbidity (7 ​% [95 ​% CI 6.9 ​%–8.1 ​%]), LOS (3 day [95 ​% CI 3–4]), costs ($9015 [95 ​% CI $8216- $9446]), and discharges to skilled facilities (1 ​% [95 ​% CI 0.9 ​%–1.6 ​%]) compared to successful nonoperative treatment. Patients ≥65 had differences in morbidity (14 ​% [95 ​% CI 13.6 ​%–16.2 ​%]), LOS (6 days [95 ​% CI 5–6]), costs ($15,964 [95 ​% CI $15,181- $17,708]), and discharges to skilled facilities (12 ​% [95 ​% CI: 10.0 ​%-13.3]) compared to nonoperative success. ConclusionsNonoperative management of appendicitis should be approached cautiously for older adults.

Retraction: Cecal Lipoma: A Rare Etiology of Acute Appendicitis in Adults.

[This retracts the article DOI: 10.7759/cureus.19423.].

Validation of scoring systems for the prediction of complicated appendicitis in adults using clinical and computed tomographic findings

ObjectivesThe study aimed to evaluate scoring systems for predicting complicated appendicitis in adults diagnosed with acute appendicitis on computed tomography.MethodsThree hundred twenty-five consecutive adult patients (mean age 51.9 ± 19.6 years, 212 women) diagnosed with acute appendicitis on computed tomography were retrospectively included. Clinical and imaging findings were compared between patients with and without complicated appendicitis, and independent associations were identified. As C-reactive protein was not available for most patients, 5 out of 8 scoring systems were modified. They, and a newly proposed system, were compared via area under the receiver operating characteristics (ROC) curve (AUC), Additionally, the latter was internally validated. Pairwise comparison was performed, and diagnostic performance of these scoring systems was obtained.ResultsOne hundred twenty-seven patients (36.8%) had complicated appendicitis. Significant independent associations were found between complicated appendicitis and duration of symptoms > 12 h, appendicolith, periappendiceal fat stranding, periappendiceal fluid, and extraluminal air (p values < 0.001 to 0.037; AUCs of 0.824–0.829). AUCs of 9 scoring systems ranged from 0.692 to 0.831. Of these, modified Atema, Kim HY, and proposed scores had similarly high and non-significantly different AUCs (0.793–0.831) on pairwise comparison. Their sensitivities, specificities, and accuracies were 73.0–90.6%, 48.5–70.6%, and 64.3–72.3%, respectively. Internal validity test demonstrated high AUCs (0.826–0.844) with one of the proposed scores using odds ratio having 100% sensitivity and 100% negative predictive value.ConclusionsFew scoring systems, including proposed ones, had high AUCs, sensitivity, and reasonable specificities, which could potentially aid in safely selecting adult patients with acute appendicitis for nonoperative management.Critical relevance statementThe study suggests few scoring systems for predicting complicated appendicitis with high AUCs and reasonable sensitivities, potentially aiding in selecting patients for nonoperative management.Key points• The study evaluated existing and proposed new scoring systems to predict complicated appendicitis in adults with acute appendicitis on computed tomography.• Several factors were found to be significantly associated with complicated appendicitis, including duration of symptoms, appendicolith, periappendiceal fat stranding, periappendiceal fluid, and extraluminal air.• The modified Atema, Kim HY, and newly proposed scoring systems performed well, potentially aiding in nonoperative management selection.Graphical