Ruling out Appendicitis in Children: Can We Use Clinical Prediction Rules?

Development and validation of a clinical prediction rule for acute appendicitis in children in primary care

BACKGROUND

Recognising acute appendicitis in children presenting with acute abdominal pain in primary care is challenging. General practitioners (GPs) may benefit from a clinical prediction rule.

OBJECTIVES

To develop and validate a clinical prediction rule for acute appendicitis in children presenting with acute abdominal pain in primary care.

METHODS

In a historical cohort study data was retrieved from GP electronic health records included in the Integrated Primary Care Information database. We assigned children aged 4-18 years presenting with acute abdominal pain (≤ 7 days) to development (2010-2012) and validation (2013-2016) cohorts, using acute appendicitis within six weeks as the outcome. Multiple logistic regression was used to develop a prediction model based on predictors with > 50% data availability derived from existing rules for secondary care. We performed internal and external temporal validation and derived a point score to stratify risk of appendicitis into three groups, i.e. low-risk, medium-risk and high-risk.

RESULTS

The development and validation cohorts included 2,041 and 3,650 children, of whom 95 (4.6%) and 195 (5.3%) had acute appendicitis. The model included male sex, pain duration (<24, 24-48, > 48 h), nausea/vomiting, elevated temperature (≥ 37.3 °C), abnormal bowel sounds, right lower quadrant tenderness, and peritoneal irritation. Internal and temporal validation showed good discrimination (C-statistics: 0.93 and 0.90, respectively) and excellent calibration. In the three groups, the risks of acute appendicitis were 0.5%, 7.5%, and 41%.

CONCLUSION

Combined with further testing in the medium-risk group, the prediction rule could improve clinical decision making and outcomes.

Presentation management and outcome of phlegmonous and inflammed appendicitis in children in Ethiopia: retrospective review

BACKGROUND

Acute appendicitis is the leading cause of emergency pediatric surgical admissions in the world. The diagnosis is may be difficult and is often dependent on clinical parameters. This study was aimed at reviewing the clinical presentations, the management and outcomes in children with inflamed and phlegmonous appendicitis with reference to the operative findings.

METHODS

The records of 211 children 5 to 15 years of age who were operated for acute appendicitis with intra operative findings of inflamed or phlegmonous appendicitis who met inclusion criteria were entered and analyzed using SPSS (IBM) V.26. Descriptive and regression tests were done with p < 0.05 considered statistically significant.

RESULTS

Of 211 children with inflamed and phlegmonous appendicitis, the M: F was 1.48:1 with a median age of 11 years. 58.3% of them presented within 24 h with the commonest symptoms being right lower abdominal pain, anorexia, and vomiting (96.2%,96.2%, 85.3%,) respectively. 96.7% of them had right lower abdominal tenderness. 73% had neutrophils ≥ 75%, and of 171 patients who had abdominal ultrasound scan, 97.7% showed appendiceal diameter ≥ 6 mm. Intraoperatively 56.4% of them were found to have phlegmonous appendicitis. In a retrospective Pediatric Appendiceal Score, only 52.6% of patients fall into the high-risk category, who could be confirmed on preoperative clinical assessment. Postoperatively 90% of them discharged improved with a mean hospital stay of 2.26(SD = 0.9) days. There was no association between the sex of the child and the intraoperative finding of inflamed or phlegmonous appendicitis (p = 0.77).

CONCLUSION

Pediatric appendicitis affects more male children in their second decade of life. Most had phlegmonous appendicitis and presented within 24 h. Duration of illness has little effect on the progress of appendicitis. Surgical management is safe for inflamed and phlegmonous appendicitis with a reasonable hospital stay and a low rate of complications.

Classification systems of acute appendicitis as an indicator for paediatric surgical consultation of children with acute abdominal pain

AIM

This study examined if the classification systems for acute appendicitis could be applied in the emergency department as an indicator for surgical consultation, in order to reduce unnecessary paediatric surgery admission.

METHODS

The Alvarado Score (ALS) and the Pediatric Appendicitis Score (PAS) were applied. The decisions for hospitalisation and treatment were made independent of the scores.

RESULTS

In total, 307 children with abdominal pain suggestive of acute appendicitis were included. We used a cut-off point of 7 and divided the patients into groups; the group with score ≥ 7 points was considered the positive ALS and/or PAS group, and the group with score < 7 points was the negative ALS and/or PAS group. The same process for cut-values set at 6 points was followed. The joint probabilities for the 7-point-thresholds were: ALS-sensitivity 84%, PAS-sensitivity 85%, ALS-specificity 92%, PAS-specificity 92%, ALS-positive predictive value (PPV) 83%, PAS-PPV 84% and 93% negative predictive value (NPV) for both scores. Considering the 6-point-thresholds, we estimated: 94% sensitivity for both scores, 74% ALS-specificity, 84% PAS-specificity, 66% ALS-PPV, 73% PAS-PPV, 91% ALS-NPV and 97% PAS-NPV.

CONCLUSION

The scoring systems provided acceptable prediction of patients with and without appendicitis. They may be of use in the emergency department, as assistive diagnostic-tools, in order to reduce paediatric surgery consultations, admissions and treatment costs.

Association of Appendicitis Incidence With Warmer Weather Independent of Season

IMPORTANCE

Acute appendicitis is a common cause of abdominal pain and the most common reason for emergency surgery in several countries. Increased cases during summer months have been reported.

OBJECTIVE

To investigate the incidence of acute appendicitis by considering local temperature patterns in geographic regions with different climate over several years.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used insurance claims data from the MarketScan Commercial Claims and Encounters Database and the Medicare Supplemental and Coordination of Benefits Database from January 1, 2001, to December 31, 2017. The cohort included individuals at risk for appendicitis who were enrolled in US insurance plans that contribute data to the MarketScan databases. Cases of appendicitis in the inpatient, outpatient, and emergency department settings were identified using International Classification of Diseases, Ninth Revision, Clinical Modification or International Statistical Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes. Local weather data were obtained for individuals living in a metropolitan statistical area (MSA) from the Integrated Surface Database. Associations were characterized using a fixed-effects generalized linear model based on a negative binomial distribution. The model was adjusted for age, sex, and day of week and included fixed effects for year and MSA. The generalized linear model was fit with a piecewise linear model by searching each 0.56 °C in temperature for change points. To further isolate the role of temperature, observed temperature was replaced with the expected temperature and the deviation of the observed temperature from the expected temperature for a given city on a given day of year. Data were analyzed from October 1, 2021, to July 31, 2022.

MAIN OUTCOMES AND MEASURES

The primary outcome was the daily number of appendicitis cases in a given city stratified by age and sex, with mean temperature in the MSA over the previous 7 days as the independent variable.

RESULTS

A total of 450 723 744 person-years at risk and 689 917 patients with appendicitis (mean [SD] age, 35 [18] years; 347 473 male [50.4%] individuals) were included. Every 5.56 °C increase in temperature was associated with a 1.3% increase in the incidence of appendicitis (incidence rate ratio [IRR], 1.01; 95% CI, 1.01-1.02) when temperatures were 10.56 °C or lower and a 2.9% increase in incidence (IRR, 1.03; 95% CI, 1.03-1.03) for temperatures higher than 10.56 °C. In terms of temperature deviations, a higher-than-expected temperature increase greater than 5.56 °C was associated with a 3.3% (95% CI, 1.0%-5.7%) increase in the incidence of appendicitis compared with days with near-0 deviations.

CONCLUSIONS AND RELEVANCE

Results of this cohort study observed seasonality in the incidence of appendicitis and found an association between increased incidence and warmer weather. These results could help elucidate the mechanism of appendicitis.

Diagnostic Value of Clinical Prediction Scores for Acute Appendicitis in Children Younger than 4 Years

INTRODUCTION

 Acute appendicitis can be difficult to diagnose, especially in children < 4 years old. The aim of the present study was to assess the diagnostic value of Alvarado score (AS), appendicitis inflammatory response (AIR) score, and pediatric appendicitis score (PAS) in children younger than 4 years.

MATERIALS AND METHODS

 All children younger than 4 years who underwent appendicectomy between 2005 and 2019 were included retrospectively. The diagnostic performance of the scores was analyzed using the area under the receiver-operating characteristic (ROC) curve and by calculating the diagnostic performances at optimal criterion value cutoff points.

RESULTS

 In this study, 100 children were included (58 boys and 42 girls) with a median age of 39.5 (12-47) months. Ninety children were diagnosed with pathologically proven acute appendicitis. The area under ROC curve of AS was 0.73, AIR score was 0.79, and PAS was 0.69 (p > 0.05, respectively). In children with low risk of acute appendicitis, negative predictive values were 75.0% for AS, 50.0% for AIR score, and 66.7% for PAS (p < 0.05, respectively). The positive predictive values in children with high risk of acute appendicitis were of 92.7% for AS, 92.6% for AIR score, and 93.6% for PAS (p > 0.05, respectively). AS, AIR score, and PAS plus positive ultrasonography have 0.58, 0.49, and 0.88 area under ROC curve.

CONCLUSION

 The three scores can be of assistance in the suspicion of acute appendicitis. PAS markedly improved combined with positive ultrasonography, but none can be used in setting the diagnosis of acute appendicitis in young children.

Predictive scoring systems to differentiate between simple and complex appendicitis in children (PRE-APP study)

BACKGROUND

Several clinical prediction rules have been developed for preoperative differentiation between simple and complex appendicitis in children, as potential treatment strategies differ. This study aimed to externally validate applicable clinical prediction rules that could be used to differentiate between simple and complex appendicitis in children.

METHODS

Potential clinical prediction rules were identified by a scoping review of the literature. Clinical prediction rules applicable in our daily practice were subsequently externally validated in a multicenter historical cohort consisting of 1 tertiary center and 1 large teaching hospital. All children (<18 years old) with histopathologically confirmed acute appendicitis between 2013 and 2020 were included. Test results of clinical prediction rules were compared to the gold standard of either simple or complex appendicitis consisting of predefined perioperative and histopathological criteria. Areas under the receiver operating characteristic curves were determined for the selected clinical prediction rules. Areas under the receiver operating characteristic curve >0.7 were considered acceptable and potentially useful.

RESULTS

In total, 31 clinical prediction rules were identified, of which 12 could be evaluated in our cohort consisting of 550 children. The main reason to exclude clinical prediction rules was the use of variables that were not routinely measured in our cohort. In our cohort, 208/550 (38%) were diagnosed with complex appendicitis according to the gold standard. Clinical prediction rules with areas under the receiver operating characteristic curve >0.7 were: Gorter (0.81), Bogaard (0.79), Bröker (0.79), Graham (0.77), Hansson (0.76), BADCF (0.76), and Eddama (0.75).

CONCLUSION

In this study, clinical prediction rules consisting of a combination of clinical and objective variables had the highest discriminative ability. External validation showed that 7 clinical prediction rules were potentially useful. Integration of these clinical prediction rules in daily practice is proposed to guide decision making regarding treatment strategies.

A New Score for the Diagnosis of Complicated Appendicitis in Children - Complicated Appendicitis Pediatric Score

Aim

This study aims to construct and validate a new score for diagnosis of complicated appendicitis in children, complicated appendicitis pediatric score (CoAPS), to guide residents' clinical decision-making on choosing the correct patients for immediate surgery, reducing the emergency negative surgeries.

Methods

This prospective observational study enrolled two cohorts of patients 5-15 years old. Four hundred and seven consecutive patients were enrolled for the derivation cohort. Demographic data, clinical features, and histopathology data were collected. The outcome measure was the histological diagnosis of gangrenous appendicitis with or without perforation. The score was next validated in a separate cohort of 312 consecutive patients who were classified according to their risk of complicated appendicitis. The diagnostic performance of the score and the potential for the risk stratification to select patients for diagnostic imaging, emergency operative management, and reduce emergency negative operation rates were quantified.

Results

A positive "jumping up" test, vomiting, white blood cell >13.5 × 10^3/ml, lymphocytes <18%, and C-reactive protein >50 mg/dl were independent predictors for complicated appendicitis. The final prediction model exhibited an area under the curve of 0.890 (95% confidence interval: 0.859-0.922). The low-risk group demonstrated high sensitivity (90.4%) for complicated appendicitis, while scores 6 or more were very specific (95%) for the disorder. Describing the potential utility of the score, emergency ultrasound imaging would have been postponed in 14.5% of patients (P = 0.0016), and emergency negative explorations would have been cut by 87%.

Conclusion

The CoAPS score could guide residents in emergency management of children with complicated appendicitis reducing hospitalizations and urgent surgeries.

Re-Assessment in Patients with Suspected Acute Appendicitis

Background: The effect of diagnosing appendicitis at re-assessment on post-operative outcomes is not clear. This study aims to compare patients diagnosed with appendicitis at initial presentation versus patients who were diagnosed at re-assessment. Patients and Methods: Data from the Dutch SNAPSHOT appendicitis collaborative was used. Patients with appendicitis who underwent appendectomy were included. Effects of diagnosis at re-assessment were compared with diagnosis at initial presentation. Primary outcomes were the proportion of patients with complicated appendicitis and the post-operative complication rate. Results: Of 1,832 patients, 245 (13.4%) were diagnosed at re-assessment. Re-assessed patients had a post-operative complication rate comparable to those diagnosed with appendicitis at initial presentation (15.1% vs. 12.7%; p = 0.29) and no substantial difference was found in the proportion of patients with complicated appendicitis (27.9% vs. 33.5%; p = 0.07). For patients with complicated appendicitis, more post-operative complications were seen if diagnosed at re-assessment than if diagnosed initially (38.2% vs. 22.9%; p = 0.006). Conclusions: For patients in whom appendicitis was not diagnosed at first presentation, but at re-assessment, both the proportion of complicated appendicitis and the post-operative complication rate were comparable to those who were diagnosed with appendicitis at initial presentation. However, re-assessed patients with complicated appendicitis encountered more post-operative complications.

RIPASA versus Alvarado score in the assessment of suspected appendicitis in children: a prospective study

Background

Diagnosis of acute appendicitis remains a problem in children with right lower quadrant pain.

Challenging diagnosis and fears of missing an inflamed appendix may lead to a negative appendectomy. Many scoring systems have been developed to reduce ambiguities in the diagnosis of appendicitis. Alvarado is one of the most commonly used scoring methods in pediatric patients. The RIPASA score is considered to be a better diagnostic scoring method in adults compared to Alvarado. The present study aims to compare RIPASA and Alvarado scoring systems in determining the possibility of acute appendicitis in children with right lower quadrant pain.

This study included 179 consecutive pediatric patients who were referred to pediatric surgery with suspicion of acute appendicitis. The cut-off value was >7.5 for the RIPASA score vs. ≥7 for the Alvarado score. The possibility of appendicitis was divided into three groups for the Alvarado score and four groups for the RIPASA score.

Results

In this study, 158 of 179 patients were operated on. In 140 of the operated patients, the diagnosis of appendicitis was confirmed by histopathology. The negative appendectomy rate was 11.4%. Specificity and negative predictive value of RIPASA score were higher than those of Alvarado (p<0.001). No difference was found between the two scores concerning sensitivity, positive predictive value, and the area under the receiver operator characteristics curve (p>0.05).

Conclusion

The RIPASA scoring system can be used as an alternative to the Alvarado scoring system in the management of patients with right lower quadrant pain in emergency services and pediatric outpatient clinics. With the use of the RIPASA score, more patients with a low likelihood of appendicitis can be detected and further contributed to the reduction of the negative appendectomy rate.

Total Leukocyte Count Depicting the Degree of Inflammation in Acute Appendicitis

Introduction Acute appendicitis (AA) is the most common cause of acute abdomen in young adults. The diagnosis is usually made on various clinical findings. However, a missed case of acute appendicitis is a catastrophe as it later presents with life-threatening complications and results in medicolegal issues. Raised total leukocyte count (TLC) is a frequent finding in patients with acute appendicitis. As a convention, a normal leukocyte count usually rules out the differential diagnosis of acute appendicitis. Recent studies claimed that a substantial proportion of patients with normal TLC also had acute appendicitis and warranted a careful evaluation of such cases before sending them home. However, the reported frequency of acute appendicitis among TLC normal patients varied greatly among studies which necessitated the present study. Aim Our aim was to determine the frequency of acute appendicitis in patients of normal TLC. Materials and methods This descriptive cross-sectional study was conducted at the Department of Surgery, KRL Hospital Islamabad. This study was carried out from 1 July 2019 to 31 December 2019. This study involved 238 patients of both genders aged between 12 and 70 years suspected of acute appendicitis on physical and ultrasound findings but with a normal TLC (4,500-11,000 WBCs/µL). The outcome variable was the frequency of acute appendicitis among such patients which was diagnosed upon surgery (inflamed appendix with free fluid) and histopathology of excised tissue (mucosal inflammation, neutrophil infiltrates, wall necrosis). Frequency of acute appendicitis was compared across various age and gender groups. Written informed consent was obtained from every patient. Results The mean age of the patients was 27.4±15.5 years. Majority (n = 167, 70.2%) of the patients were aged ≤25 years, followed by 40 (16.8%) patients aged ≥46 years and 31 (13.0%) patients aged between 26 and 45 years. There were 135 (56.7%) male and 103 (43.3%) female patients with a male to female ratio of 1.3:1. All of the patients (100.0%) had pain in the right iliac fossa (RIF) while rebound tenderness, anorexia, nausea/vomiting, fever and dysuria were noted in 83.6%, 79.0%, 73.9%, 63.9% and 15.1% patients, respectively. The diagnosis of acute appendicitis was made in 198 (83.2%) patients with normal TLC and suspicion of acute appendicitis on physical findings and ultrasound. When stratified, there was no statistically significant difference in the frequency of acute appendicitis across various age (p-value = 0.988) and gender (p-value = 0.913) groups. Conclusion In the present study, contrary to the routine impression that normal TLC rules out the differential diagnosis of acute appendicitis, a substantial proportion of patients with clinical and ultrasound suspicion of acute appendicitis but normal TLC had acute appendicitis which is worrisome as a missed case may later present with complications. The present study thus warrants cautious evaluation of clinically suspected cases with normal TLC count to avoid a missed appendicitis and improve the outcome in future surgical practice.

Clinical Prediction Scores for Pediatric Appendicitis

INTRODUCTION

 The rate of misdiagnosis of appendicitis in children is a challenge and clinical prediction scores could be part of the solution. However, the pediatric appendicitis score (PAS) and the Alvarado score have shown disappointing diagnostic accuracy in pediatric validation studies, while the appendicitis inflammatory response (AIR) score and the novel pediatric appendicitis risk calculator (pARC) have not yet been validated thoroughly. Therefore, the aim of the present study was to evaluate these four prediction scores prospectively in children with suspected appendicitis.

MATERIALS AND METHODS

 A prospective study was conducted over a 2-year period. All patients <15 years with suspected appendicitis were eligible for inclusion. The four prediction scores were compared regarding predictive values, receiver operating characteristics (ROC) curves, decision curve analysis, and clinical outcome.

RESULTS

 Of the 318 patients included, 151 (47 %) patients had appendicitis. The AIR score and the pARC had substantially higher specificity and positive predictive value, and lower rate of false positives (7% and 2%), than the PAS and Alvarado score (36 and 28%, p < 0.001). Across the different gender and age groups, the AIR score and the pARC generally had fewer false positives than the PAS and Alvarado score. There were no significant differences in sensitivity, negative predictive values, rates of missed appendicitis, or ROC curve analysis. In decision curve analysis, the AIR score and the pARC outperformed the PAS and Alvarado score at most threshold probabilities.

CONCLUSION

 The AIR score and the pARC are superior to the PAS and Alvarado score in diagnosing children with suspected appendicitis.

The Use of Machine Learning Approaches for the Diagnosis of Acute Appendicitis

Acute appendicitis is one of the most common emergency diseases in general surgery clinics. It is more common, especially between the ages of 10 and 30 years. Additionally, approximately 7% of the entire population is diagnosed with acute appendicitis at some time in their lives and requires surgery. The study aims to develop an easy, fast, and accurate estimation method for early acute appendicitis diagnosis using machine learning algorithms. Retrospective clinical records were analyzed with predictive data mining models. The predictive success of the models obtained by various machine learning algorithms was compared. A total of 595 clinical records were used in the study, including 348 males (58.49%) and 247 females (41.51%). It was found that the gradient boosted trees algorithm achieves the best success with an accurate prediction success of 95.31%. In this study, an estimation method based on machine learning was developed to identify individuals with acute appendicitis. It is thought that this method will benefit patients with signs of appendicitis, especially in emergency departments in hospitals.

Appendicitis risk prediction models in children presenting with right iliac fossa pain (RIFT study): a prospective, multicentre validation study

BACKGROUND

Acute appendicitis is the most common surgical emergency in children. Differentiation of acute appendicitis from conditions that do not require operative management can be challenging in children. This study aimed to identify the optimum risk prediction model to stratify acute appendicitis risk in children.

METHODS

We did a rapid review to identify acute appendicitis risk prediction models. A prospective, multicentre cohort study was then done to evaluate performance of these models. Children (aged 5-15 years) presenting with acute right iliac fossa pain in the UK and Ireland were included. For each model, score cutoff thresholds were systematically varied to identify the best achievable specificity while maintaining a failure rate (ie, proportion of patients identified as low risk who had acute appendicitis) less than 5%. The normal appendicectomy rate was the proportion of resected appendixes found to be normal on histopathological examination.

FINDINGS

15 risk prediction models were identified that could be assessed. The cohort study enrolled 1827 children from 139 centres, of whom 630 (34·5%) underwent appendicectomy. The normal appendicectomy rate was 15·9% (100 of 630 patients). The Shera score was the best performing model, with an area under the curve of 0·84 (95% CI 0·82-0·86). Applying score cutoffs of 3 points or lower for children aged 5-10 years and girls aged 11-15 years, and 2 points or lower for boys aged 11-15 years, the failure rate was 3·3% (95% CI 2·0-5·2; 18 of 539 patients), specificity was 44·3% (95% CI 41·4-47·2; 521 of 1176), and positive predictive value was 41·4% (38·5-44·4; 463 of 1118). Positive predictive value for the Shera score with a cutoff of 6 points or lower (72·6%, 67·4-77·4) was similar to that of ultrasound scan (75·0%, 65·3-83·1).

INTERPRETATION

The Shera score has the potential to identify a large group of children at low risk of acute appendicitis who could be considered for early discharge. Risk scoring does not identify children who should proceed directly to surgery. Medium-risk and high-risk children should undergo routine preoperative ultrasound imaging by operators trained to assess for acute appendicitis, and MRI or low-dose CT if uncertainty remains.

FUNDING

None.