Pediatric appendicitis remains a common diagnostic challenge faced in the emergency department. In this review, we provide an update on recent literature regarding the diagnosis of pediatric appendicitis via labs, imaging, and clinical prediction scores, and provide a summary of key pitfalls in diagnosing this condition.

Progress has been made in laboratory evaluation for the diagnosis of pediatric appendicitis with newer markers being under investigation, though standard markers such as white blood cell count and C-reactive protein remain prominent. From an imaging standpoint, there is emphasis on the use of ultrasound as the primary imaging modality, and creating new protocols for magnetic resonance imaging as a secondary imaging method if ultrasound is inconclusive. Clinical prediction scores continue to be a promising diagnostic tool with the literature indicating high specificity but rather low sensitivity. A wide array of diagnostic practices exist creating disparities in care, particularly with imaging.

Pediatric appendicitis is a challenging diagnosis with ongoing research efforts focused on novel laboratory markers that are more sensitive and specific, prioritizing the use of nonionizing radiation imaging modalities, and improving reliability of clinical prediction scoring tools. Reducing disparities in care surrounding pediatric appendicitis should be a focus for future research.

Ultrasonography (USG), which is used as the first step in the diagnosis of acute appendicitis (AA), sometimes cannot visualize the appendix. The aim of this study was to retrospectively analyze the clinical, imaging, and pathology results of these cases and to provide information to clinicians about the next step to be taken.

The study was performed retrospectively between January 1, 2021 and December 31, 2021. Patients with a prediagnosis of AA who underwent USG as the first-line imaging modality and in whom the appendix could not be visualized were included. Imaging, clinical, and pathology results of the patients were analyzed, and the study was completed by comparing patients with and without computed tomography (CT) scans as well as patients with and without AA diagnosis.

The study included 176 patients aged 18-89 years, 63 (35.8%) of whom were male and 113 (64.2%) female. The mean age was 37.5 ± 17.8 years. CT was not performed in 97 patients (55.1%), while it was performed in 79 patients (44.9%). Of the patients, 121 (68.7%) were discharged and 55 (31.2%) were hospitalized. Of the patients who were hospitalized, 36 (20.5%) received medical treatment and 19 (10.7%) received surgical treatment. Fifteen patients (8.5%) were pathologically diagnosed with AA. Two patients (1.1%) who were discharged without CT were subsequently diagnosed with AA. The white blood cell (WBC) count of patients operated on for AA was 13.4 ± 3.9 × 103/mL, while the WBC count of the other patients was 10.3 ± 4.2 × 103/mL (p = 0.009). The proportion of patients with an Alvarado score of ≥ 6 was 80% in patients diagnosed with AA, while this rate was 4.3% in other patients (p < 0.001).

In cases of a nonvisualized appendix on USG, the absence of leukocytosis and an Alvarado score below 6 may suggest a reduced likelihood of AA. Consequently, further investigations, such as CT and magnetic resonance imaging, could be avoided.

Uncertainty is inherent in medical practice. False-negative decisions can delay treatments and result in adverse outcomes in children with acute appendicitis (AA). On the other hand, false-positive surgery decisions lead to unnecessary appendectomies. Impressive technological advancements, such as magnetic resonance imaging and laparoscopy, have reduced but failed to eliminate the occurrence of erroneous decisions. Furthermore, there seems to be a fundamental limit to further reduction, especially in eliminating the rates of negative appendectomy or, oppositely, complicated appendicitis. What does this mean for the pediatric surgeon? Will we ever be able to eliminate our mistakes? This systematic review emphasizes the importance of understanding the potential abilities and limitations of different diagnostic options, as well as the impact of decisions in the face of uncertainty.

Meningitis, appendicitis, and testicular torsion are among the most common conditions resulting in malpractice litigation in Pediatric Emergency Medicine. With meningitis, most litigation claims involved patients <2 years old. Notably, 25% of patients had no fever and many lacked classic signs of meningitis. For appendicitis, nearly 3/4 of litigated cases claimed delayed/missed diagnosis. A non-diagnostic ultrasound (eg, no appendix visualized) has a negative predictive value of only 86%. Finally, testicular torsion carries a 34-42% testicular loss rate and 10% of patients with torsion only present with isolated abdominal pain. Atypical presentations must be considered and clear return precautions are imperative.

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

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

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

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

Point-of-care ultrasound has been shown to have excellent diagnostic accuracy for a variety of gastrointestinal and biliary pathologies. This review explores the evidence and scanning techniques for hypertrophic pyloric stenosis, intussusception, appendicitis, small bowel obstruction, diverticulitis, hernias, pneumoperitoneum, and biliary pathology.

Pediatric surgical care is becoming increasingly regionalized, often resulting in limited access. Interfacility transfers pose a significant financial and emotional burden to when they are potentially avoidable. Of transferred patients, we sought to identify clinical factors associated with avoidable transfers in pediatric patients with suspected appendicitis.

We performed a single-center retrospective study at an academic tertiary referral children's hospital in an urban setting. We included children who underwent interfacility transfer to our center with a transfer diagnosis of appendicitis from July 1, 2021 to June 30, 2023. Encounters were designated as either an appropriate transfer (underwent appendectomy) or an avoidable transfer (did not undergo appendectomy). Encounters treated nonoperatively for complicated appendicitis were excluded. Bivariate analysis was performed using Mann-Whitney test and chi-square tests.

A total of 444 patients were included: 71.2% were classified as appropriate transfers and 28.8% as avoidable transfers. Patients with avoidable transfer were younger compared to those in the appropriate transfer cohort (median age 9 y, interquartile range: 7-13 versus 11 y, interquartile range: 8-14; P < 0.001). Avoidable transfers less frequently presented with the typical symptoms of fever, migratory abdominal pain, anorexia, and nausea/emesis (P = 0.005). Avoidable transfers also reported shorter symptom duration (P = 0.040) with lower median white blood cell count (P < 0.001), neutrophil percentage (P < 0.001), and C-reactive protein levels (P < 0.003). Avoidable transfers more frequently underwent repeat imaging upon arrival (42.9% versus 12.7%, P < 0.001).

These findings highlight the importance of clinical history in children with suspected appendicitis. Younger patients without typical symptoms of appendicitis, those with a shorter duration of symptoms, and lower serum inflammatory markers may benefit from close observation without transfer.

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

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

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

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

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

Background: Most studies have demonstrated the high accuracy of ultrasound for the diagnosis of acute appendicitis (AA) in children. However, the lack of visualization of the appendix on ultrasound is usually a challenge. The aim of this study was to identify any factors that might help the physician make the right decision when dealing with a child with suspected appendicitis and an appendix not seen on ultrasound. Patients and Methods: After receiving Institutional Review Board approval, we conducted a prospective study in a pediatric emergency department from January 1, 2022, to December 31, 2022. All children under 14 years of age with suspected AA and an appendix not visualized on ultrasound were included. Results: During the study period, 333 children presented with suspected AA. Of these patients, 106 had an appendix not seen on ultrasound. Our patients' median age was 10 years (interquartile range [IQR], 8-11 years), with 54.7% (n = 58) of children being female. Twenty-five (23.6%) were ultimately diagnosed with AA based on pathologic examination. Multivariable logistic regression analysis revealed that Alvarado score ≥6 and increased peri-appendiceal fat echogenicity were predictive for AA. The combination of these two factors provided a positive predictive value of 100%. A white blood cell (WBC) count ≤10 × 109/L and/or a C-reactive protein (CRP) level ≤6 mg/L makes the diagnosis of appendicitis unlikely. Conclusions: In conclusion, our study demonstrated that an Alvarado score at or above six and increased peri-appendiceal fat echogenicity are independent predictive factors of AA in children with non-visualized appendix on ultrasound. The combination of these two factors would confirm the diagnosis of AA in these patients.

This study aimed to identify the patient characteristics, history factors, physical examination findings, and sonographic findings, which contribute to a higher risk of the appendix not being visualized on ultrasound evaluation (ie, nondiagnostic or equivocal study) in patients being evaluated for appendicitis. Secondarily, this study assessed the utility of an equivocal ultrasound, specifically in the ability to predict the absence of appendicitis.

A retrospective case review was performed, of children (age, 0-18 years) presenting to a pediatric emergency department with clinical suspicion for appendicitis, who underwent sonographic studies during the 12-month study period.

Five hundred forty-three cases were reviewed, of which 75 (14%) were diagnosed with appendicitis. The sensitivity of ultrasound diagnosis of appendicitis was 62.7% and specificity was 79.1%. The appendix was not visualized in 398 (73%) cases. Of the cases where the appendix was not visualized, 370 did not have appendicitis (negative predictive value, 93%). In cases where the appendix was not visualized and the white blood cell count was less than 10,000, the negative predictive value rose to 97%. The patient's age (odds ratio [OR], 1.049), weight (OR, 1.015), presence of appendicolith (OR, 0.426), presence of right lower quadrant fat stranding on sonography (OR, 0.081), and presence of hyperemia on sonography (OR, 0.094) were found to be significant in affecting the visualization of the appendix on ultrasound.

Increasing patient's age and weight leads to increased likelihood that the appendix will not be visualized on ultrasound, whereas the presence of an appendicolith, right lower quadrant fat stranding or hyperemia will increase the likelihood of visualization. The sensitivity and specificity of ultrasound for the diagnosis of appendicitis are moderate but the negative predictive value of an equivocal study is high. Clinicians can use supporting clinical examination and laboratory findings, in conjunction with a nondiagnostic ultrasound evaluation of the appendix to exclude the diagnosis of appendicitis, without the need for further imaging.

Abdominal pain represents 5% to 7% of all emergency department presentations. Many patients require imaging for diagnosis, and choosing the appropriate imaging modality is a crucial decision point. Modern medicine offers a fantastic array of options including abdominal radiograph, computed tomography, MRI, and ultrasonography, but the plethora of alternatives can be paralyzing. This article introduces the commonly available modalities, discusses the advantages and disadvantages, and presents current recommendations for commonly diagnosed conditions.

While many cases of appendicitis are easy to diagnose clinically, a significant number need further workup in the form of imaging. Ultrasound and CT are both used extensively to diagnose or exclude appendicitis, or arrive at an alternate diagnosis. Ultrasound has many advantages but can be a difficult modality to use due to, among other reasons, the anatomical variations in appendicial location. The true retrocolic appendix is particularly difficult to diagnose with ultrasound. This pictorial essay examines the ultrasound features of normal and diseased appendix and proposes a new examining station, the prone view, for visualizing true retrocolic appendicitis.

Oftentimes while pursing the diagnosis of appendicitis, an ultrasound cannot visualize the appendix, and physicians must utilize other resources for evaluation. The primary objective of this study was to determine if there was a lower rate of appendicitis when the appendix was not visualized on ultrasound. Furthermore, we assessed the importance of specific clinical predictors in this population.

We conducted a retrospective chart review of all children who presented to our pediatric emergency department from 2011 to 2013 and had an abdominal ultrasound. We identified total numbers of ultrasounds with a nonvisualized appendix and then assessed follow-up for a randomly selected group of patients. We performed logistic regression to assess the predictive value of different clinical factors.

A total of 3245 ultrasounds were analyzed, and in 54% of these, the appendix was nonvisualized. In total, 28% of the total patients and 11.9% of patients who received a nonvisualized ultrasound had appendicitis (95% confidence interval [CI], 8.3%-16.2%). Among those patients who had follow-up studies performed during the same visit, 21.2% had appendicitis (95% CI, 14.9%-28.8%), and of those discharged without a diagnosis, 1.5% had appendicitis (95% CI, 0.2%-5.4%). Male sex, leukocytosis, and an elevated absolute neutrophil count were each significantly associated with appendicitis after a nonvisualized appendix on ultrasound.

A significant proportion of patients with suspected appendicitis who had an initial nonvisualized appendix on ultrasound were ultimately diagnosed with appendicitis. Clinicians must be vigilant about pursuing a definitive diagnosis if an initial ultrasound is nondiagnostic.

Point-of-care ultrasound has become an essential part of pediatric emergency medicine training and practice. It can have significant clinical benefits, including improving diagnostic accuracy and decreasing length of stay, and does not require radiation exposure for patients. In this review, we summarize the current diagnostic point-of-care ultrasound applications in pediatric emergency medicine, their evidence, and techniques.

The diagnosis of acute appendicitis (AA) remains a clinical one, with selective use of adjunct imaging. Patients with equivocal clinical presentation often undergo a diagnostic laparoscopy. To help reduce negative appendicectomy rates in women, we aimed to develop a simple scoring system based on the Alvarado score (AS) and ultrasound scan (US), as a diagnostic aid for AA in females.

All patients who underwent appendicectomy for AA at The Alfred Hospital Melbourne between 1 July 2012 and 30 June 2017 were included for this case-control study. Logistic regression was used to identify pre-operative parameters predictive of AA. Histopathological identification of AA was interpreted as the gold standard. Statistical analysis was performed using IBM SPSS Statistics V26.

A total of 1194 patients were included, with 26% negative appendicectomy rate in women. Of the 8 parameters in the AS, logistic regression identified migratory pain, leukocytosis and leukocyte left shift as most significant predictors for AA. These three parameters were used in a 3-point test which carried a sensitivity of 92.1% and specificity of 28.7%. In women, a negative or non-diagnostic US improved the negative predictive value of the 3-point test from 57% to 82%.

The 3-point abbreviated AS in combination with US may be clinically useful in women to exclude appendicitis without diagnostic laparoscopy. Further large-scale prospective studies are required to validate the utility across different subgroups.

Background: Given the absence of consolidated and standardized international guidelines for managing pediatric appendicitis and the few strictly data-driven studies in this specific, we investigated the use of machine learning (ML) classifiers for predicting the diagnosis, management and severity of appendicitis in children. Materials and Methods: Predictive models were developed and validated on a dataset acquired from 430 children and adolescents aged 0-18 years, based on a range of information encompassing history, clinical examination, laboratory parameters, and abdominal ultrasonography. Logistic regression, random forests, and gradient boosting machines were used for predicting the three target variables. Results: A random forest classifier achieved areas under the precision-recall curve of 0.94, 0.92, and 0.70, respectively, for the diagnosis, management, and severity of appendicitis. We identified smaller subsets of 6, 17, and 18 predictors for each of targets that sufficed to achieve the same performance as the model based on the full set of 38 variables. We used these findings to develop the user-friendly online Appendicitis Prediction Tool for children with suspected appendicitis. Discussion: This pilot study considered the most extensive set of predictor and target variables to date and is the first to simultaneously predict all three targets in children: diagnosis, management, and severity. Moreover, this study presents the first ML model for appendicitis that was deployed as an open access easy-to-use online tool. Conclusion: ML algorithms help to overcome the diagnostic and management challenges posed by appendicitis in children and pave the way toward a more personalized approach to medical decision-making. Further validation studies are needed to develop a finished clinical decision support system.

Secondary sonographic findings of appendicitis can aid image analysis and support diagnosis with and without visualization of an appendix.

We sought to determine if age affected the test performance of secondary findings for pediatric appendicitis.

We performed a medical record review of emergency department patients younger than 19 years of age who had a sonogram for suspected appendicitis. Our primary patient outcome was appendicitis, as determined by pathology or by image-confirmed perforation/abscess. Our primary analysis was test performance of secondary sonographic findings as recorded by sonographers on the final diagnosis of appendicitis stratified by age (<6 years, 6 to <11 years, 11 to <19 years).

A total of 1,219 patients with suspected appendicitis were evaluated by ultrasound, and 1,147 patients met the criteria for analysis. Of the 1,147 patients, 431 (37.6%) had a final diagnosis of appendicitis. Across all age groups, echogenic fat was the most accurate secondary finding (92.5% [95% confidence interval (CI): 91.0, 94.0]) and free fluid was the least accurate secondary finding (54.7% [95% CI: 51.8, 57.5]). There was no significant difference in the age-stratified test performance of secondary sonographic findings except that (1) appendicolith was a more accurate predictor in patients <6 years old than in the middle group (P<0.001) or the oldest group (P<0.001), and (2) free fluid was a more accurate predictor in the middle group than in the oldest group (P=0.02).

There are no significant differences in the age-stratified test performance of secondary sonographic findings in the prediction of pediatric appendicitis except that appendicolith is more predictive in younger patients.

Diagnostic criteria for acute appendicitis using graded compression sonography have been well established based on the maximum outer diameter (MOD) of the appendix, with MOD values of <6 mm nearly always indicating normal appendices and MOD values of >8 mm nearly always indicating appendicitis. However, the "borderline-size" appendix, meaning one whose MOD lies between these ranges (ie, an appendix with MOD of 6-8 mm), presents a diagnostic dilemma because appendices in this size range are neither clearly normal nor abnormal when diagnosis is based on the MOD alone; accordingly, such borderline MOD values are diagnostically equivocal, and sonographic diagnosis must rely on sonographic findings other than the MOD. The goal of this review was to examine the additional sonographic findings that can add specificity and help enable an accurate diagnosis to be made in patients with borderline-size appendices.

This retrospective study was aimed to determine the factors suggesting the need for computed tomography (CT) scanning when ultrasound (US) imaging results are negative or non-diagnostic in children suspicious for acute appendicitis in the emergency department.Patients less than 18 years old who underwent abdominal ultrasound and CT to rule out acute appendicitis were enrolled. Patients were classified into 2 groups: the false-negative group, in which patients had negative or non-diagnostic results on the initial US and a final diagnosis of acute appendicitis on the following abdominal CT, and the true-negative group, in which patients had negative or non-diagnostic US results and were negative on abdominal CT. Logistic regression and propensity score matching with the predicting factors were performed.The presence of vomiting (odds ratio (OR), 7.78; 95% confidence interval (CI), 1.92-41.04) and poor oral intake (OR, 4.67; 95% CI, 1.21-21.15) with a high white blood cell (WBC) count (OR 1.26; 95% CI, 1.09-2.37), segmented neutrophil ratio (OR, 1.09; 95% CI, 1.03-1.16), and C-reactive protein (CRP) (OR, 1.49; 95% CI, 1.09-2.37) were suggestive of the false-negative group. The propensity-matched population also showed significant associations with vomiting (OR, 7.86; 95% CI, 1.65-37.40) and poor oral intake (OR, 5.50; 95% CI, 1.28-23.69) with an elevated WBC count (OR, 1.27; 95% CI, 1.08-1.50), segmented neutrophil ratio (OR, 1.09; 95% CI, 1.03-1.16), and CRP (OR, 1.51; 95% CI, 1.03-2.22).A CT scan should be considered in children with suspected acute appendicitis if they have vomiting, high CRP, and high WBC count, despite negative or non-diagnostic US results.

The aim of this study was to explore the combined negative predictive value (NPV) of symptom duration and WBC profile in children with a nondiagnostic ultrasound (US) for appendicitis.

This was a retrospective analysis of children with suspected appendicitis at a single children's hospital from 1/2010 to 3/2018. NPVs based on WBC profile and symptom duration at presentation were calculated individually and combined for children with a nondiagnostic US.

2277 patients were included, of which 1018 (44.7%) had a nondiagnostic US. The NPV of a nondiagnostic US ranged from 83.7% with ≤24 h of symptoms to 94.5% with >72 h of symptoms (p < 0.01). NPV also differed significantly across WBC profiles, ranging from 76.8% when WBC profile was elevated to 97.3% to when WBC profile was normal (p < 0.01). The range of NPVs for a nondiagnostic US was even greater when combining symptom duration and WBC profile, ranging from 73.7% for patients with 24-48 h of symptoms and an elevated WBC profile to 100% for patients with >72 h of symptoms and a normal WBC profile.

Incorporation of symptom duration and WBC profile significantly improves the accuracy and clinical utility of the negative predictive value associated with a nondiagnostic ultrasound.

Study of diagnostic test level II: development of diagnostic criteria in a consecutive series of patients and a universally applied gold standard.

Ultrasound has the first line investigation role in the diagnosis of acute appendicitis in children. The purpose of this study was to perform a quality assessment review on the visualization rate of appendix on ultrasound in children in the community hospital setting.

A retrospective chart review of the abdominal ultrasound findings for the visualization of the appendix was performed on paediatric patients ranging from 5 to 18 years. Data were collected from the two community hospitals of Toronto by using hospital electronic medical record for the ultrasound findings in patients presented with abdominal pain.

Data from two community hospitals indicated visualization rate of the appendix as 11.0% and 23.2% for site 1 and site 2 respectively. In cases where the ultrasound was repeated the visualization rate remains the same. A two-proportion z-test was performed to find whether the visualization of appendix increases the likelihood of diagnosing appendicitis. The results revealed that the visualization of an appendix (P=0.52), significantly improved the diagnosis of appendicitis (z=34, P<0.001).

Visualization of an appendix on ultrasound increases the likelihood of correctly diagnosing appendicitis. In our study, we found low visualization rate of appendix on ultrasound that could be the result of many factors that contribute towards the low visualization rate of an appendix on ultrasound. Hence, the challenges in identifying appendix should be minimized to improve the visualization and diagnosis of appendicitis on ultrasound.

Ultrasonography (US) is often the first-line imaging study used to evaluate women who present with acute or chronic pelvic pain. Detection of nongynecologic causes of pelvic pain is critical, because delay in diagnosis can cause significant morbidity and mortality. Evaluation of these entities requires a variety of transducers to achieve optimal imaging depth and changes in patient positioning. Specific imaging techniques (such as graded compression) may be required if bowel pathology is suspected. Contrast-enhanced ultrasonography is increasingly used to improve detection of certain entities. The US appearance of common gastrointestinal and urinary tract-related causes of pelvic pain is reviewed.

Non-contrast magnetic resonance imaging (MRI) and ultrasound studies in pediatric patients with suspected appendicitis are often non-diagnostic. The primary objective of this investigation was to determine if combining these non-diagnostic imaging results with white blood cell (WBC) cutoffs improves their negative predictive values (NPVs).

A retrospective chart review was conducted including patients ≤18 years old with suspected appendicitis who had MRI performed with or without a preceding ultrasound study in a pediatric emergency department. Imaging results were sorted into 2 diagnostic and 5 non-diagnostic categories. NPVs were calculated for the non-diagnostic MRI and ultrasound categories with and without combining them with WBC cutoffs of <10.0 and <7.5 × 10⁹/L.

Of the 612 patients with MRI studies included, 402 had ultrasound studies performed. MRI with incomplete visualization of a normal appendix without secondary signs of appendicitis had an NPV of 97.9% that changed to 98.1% and 98.2% when combined with WBC cutoffs of <10.0 and <7.5, respectively. Ultrasound studies with incomplete visualization of a normal appendix without secondary signs had an NPV of 85.3% that improved to 94.8% and 96.5% when combined with WBC cutoffs of <10.0 and <7.5, respectively.

In pediatric patients with suspected appendicitis, MRI studies with incomplete visualization of a normal appendix without secondary signs have a high NPV that does not significantly change with the use of these WBC cutoffs. In contrast, combining WBC cutoffs with ultrasound studies with the same interpretation identifies low-risk groups.

Secondary signs of appendicitis on ultrasound may aid with diagnosis in the setting of a non-visualized appendix (NVA). This role has not been shown in the community hospital setting.

All right lower quadrant ultrasounds performed in children for clinical suspicion of appendicitis over a 5-year period in a single community hospital were evaluated. Secondary signs of inflammation including free fluid, ileus, fat stranding, abscess, and lymphadenopathy were documented. Patients were followed for 1 year for the primary outcome of appendicitis. These data were analyzed to determine the utility of secondary signs in the diagnosis of acute appendicitis when an NVA is reported.

Six hundred and seventeen ultrasounds were reviewed; 470 of these had an NVA. Of NVAs, 47 (10%) of patients were diagnosed with appendicitis. Sensitivity and specificity of having at least one secondary were 38.3% and 80%, respectively. The positive and negative predictive values of having at least one secondary sign were 17.3% and 92%, respectively.

These data suggest that the absence of secondary signs has a strong negative predictive value for appendicitis in the community hospital setting; however, the full utility of secondary signs may be limited in this setting.

The aim of this study was to evaluate the ability of emergency physicians with various levels of point-of-care ultrasound (POCUS) experience to detect appendicitis with POCUS among children visiting a pediatric emergency department (ED).

A prospective cohort study was conducted in an urban, tertiary care pediatric ED. Children aged 2 to 18 years old who presented with acute abdominal pain suggesting appendicitis were included. Patients were excluded if they had a history of appendectomy or hemodynamic instability requiring resuscitation or were transferred with proven diagnosis of appendicitis. Participating physicians had various levels of POCUS experience. Four of the 22 physicians were experienced in bowel sonography while the others had basic experience in abdominal POCUS. All the participating physicians received a 1-hour didactic and practical training session on appendix ultrasound. The treating physician performed POCUS following initial physical examination, before further radiologic evaluation. POCUS examinations were recorded as positive for appendicitis, normal, or inconclusive, with normal or inconclusive studies considered negative. Final outcomes were determined by pathology and/or operative reports for surgical cases and telephone follow-up at 3 weeks for those who did not have surgery. The primary analysis was a simple proportion for sensitivity and specificity for POCUS. Expecting a sensitivity of 80% based on previous studies, we calculated that a sample size of 50 cases would provide a 95% confidence interval (CI) ranging from 66% to 90%.

Of the 140 approached patients, 121 accepted to participate and were recruited. After four patients were excluded for missing POCUS data, 117 patients were included in the primary analysis, of whom 51 (44%) had appendicitis. Twenty-two physicians performed between one and 20 POCUS procedures. The POCUS was positive in 39, negative in nine, and inconclusive in 69 patients. POCUS was interpreted as positive in 27 of 51 appendicitis for a sensitivity of 0.53 (95% CI = 0.40-0.66). A negative or inconclusive POCUS was reported for 54 of 66 patients without appendicitis (specificity = 0.82; 95% CI = 0.71-0.89).

This study shows limited sensitivity and specificity of POCUS for appendicitis in children, with a high proportion of inconclusive examinations, when performed by emergency physicians with various level of experience in POCUS.

Diagnosing pediatric appendicitis is difficult because clinical findings are nonspecific. Improved accuracy can be obtained with ultrasound (US), CT, or MRI, despite considerable variation in their use at different institutions. This article reviews the evidence for best practices in imaging pediatric appendicitis.

When each modality is optimally used, a stepwise imaging approach that begins with graded compression US and proceeds to CT or MRI in select cases is currently best practice.

Ultrasound (US) and laboratory testing are initial diagnostic tests for acute appendicitis. A diagnostic dilemma develops when the appendix is not visualized on US. Objective: To determine if specific US findings and/or laboratory results predict acute appendicitis when the appendix is not visualized. Methods: A prospective study was conducted on children (birth-18 yrs) presenting to the pediatric emergency department with suspected acute appendicitis who underwent right lower quadrant US. Children with previous appendectomy, US at another facility, or eloped were excluded. US findings analyzed: inflammatory changes, right lower quadrant and lower abdominal fluid, tenderness during US exam and lymph nodes. Diagnoses were confirmed via surgical pathology. Results 1252 subjects were enrolled, 60.8% (762) had appendix visualized and 39.1% (490) did not. In children where the appendix was not seen, 6.7% [33] were diagnosed with appendicitis. Among patients with a non-visualized appendix, the likelihood of appendicitis was significantly greater if: inflammatory changes in the RLQ (OR 18.0, 95% CI 4.5-72.1), CRP >0.5 mg/dL (OR 2.64, 95% CI 1.0-6.8), or WBC > 10 (OR 4.36, 95% CI 1.66-11.58). Duration of abdominal pain >3 days was significantly less likely associated with appendicitis in this model (OR 0.34, 95% CI 0.003-0.395). Combined, the absence inflammatory changes, CRP < 0.5 mg/dL, WBC < 10, and pain, ≤3 days had a NPV of 94.0%. Conclusion When the appendix is not visualized on US, predictors for appendicitis include the presence of inflammatory changes in the RLQ, an elevated WBC/CRP and abdominal pain <3 days.

Appendicitis is a common surgical condition that frequently requires diagnostic imaging. Abdominal computed tomography (CT) is the gold standard for diagnosing appendicitis. Ultrasound offers a radiation-free modality; however, its availability outside business hours is limited in many emergency departments (EDs). The purpose of this study is to evaluate the test characteristics of emergency physician-performed point-of-care ultrasound (POCUS) to diagnose appendicitis in a Canadian ED.

A health records review was performed on all ED patients who underwent POCUS to diagnose appendicitis from December 1, 2010 to December 4, 2015. The sensitivity, specificity, and likelihood ratios were calculated. The gold standard used for diagnosis was pathology, laparoscopy, CT scans, and a radiologist-performed ultrasound.

Ninety patients were included in the study, and 24 were diagnosed with appendicitis on POCUS. Ultimately, 18 were confirmed to have appendicitis through radiologist-performed imaging, laparoscopy, and pathology. The sensitivity and specificity of POCUS to diagnose appendicitis were 69.2% (95% CI, 48.1%-84.9%) and 90.6% (95% CI, 80.0%-96.1%), respectively.

POCUS has a high specificity for diagnosing acute appendicitis and has very similar characteristics to those of a radiologist-performed ultrasound. These findings are consistent with the current literature and have the potential to decrease patient morbidity, diagnostic delays, ED length of stay, and need for additional imaging.

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

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

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

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

Our objective was to increase ultrasound reliability for diagnosing appendicitis in an academic children's hospital emergency department (ED) through a multidisciplinary quality improvement initiative.

A retrospective review of ultrasound use in patients diagnosed with appendicitis in our ED from 1/1/2011 to 6/30/2014 established a baseline cohort. From 8/1/2014 to 7/31/2015 a diagnostic algorithm that prioritized ultrasound over CT was used in our ED, and a standardized template was implemented for the reporting of appendicitis-related ultrasound findings by our radiologists.

Of 627 patients diagnosed with appendicitis in the ED during the retrospective review, 46.1% (n=289) had an ultrasound. After implementation of the diagnostic algorithm and standardized ultrasound report, 88.4% (n=236) of 267 patients diagnosed with appendicitis had an ultrasound (p<0.01). The frequency of indeterminate results decreased from 44.3% to 13.1%, and positive results increased from 46.4% to 66.1% in patients with appendicitis (p<0.01). The sensitivity of ultrasound (indeterminate counted as negative) increased from 50.6% to 69.2% (p<0.01).

Ultrasound reliability for the diagnosis of appendicitis in children can be improved through standardized results reporting. However, these changes should be made as part of a multidisciplinary quality improvement initiative to account for the initial learning curve necessary to increase experience.

Level II, Study of Diagnostic Test.

The ability of ultrasound to identify specific features relevant to nonoperative management of pediatric appendicitis, such as the presence of complicated appendicitis (CA) or an appendicolith, is unknown. Our objective was to determine the reliability of ultrasound in identifying these features.

We performed a retrospective study of children who underwent appendectomy after an ultrasound at four children's hospitals. Imaging, operative, and pathology reports were reviewed. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ultrasound for identifying CA based on pathology and intraoperative findings and an appendicolith based on pathology were calculated. CA was defined as a perforation of the appendix. Equivocal ultrasounds were considered as not indicating CA.

Of 1027 patients, 77.5% had simple appendicitis, 16.2% had CA, 5.4% had no evidence of appendicitis, and 15.6% had an appendicolith. Sensitivity and specificity of ultrasound for detecting CA based on pathology were 42.2% and 90.4%; the PPV and NPV were 45.8% and 89.0%, respectively. Sensitivity and specificity of ultrasound for detecting CA based on intraoperative findings were 37.3% and 92.7%; the PPV and NPV were 63.4% and 81.4%, respectively. Sensitivity and specificity of ultrasound for detecting an appendicolith based on pathology were 58.1% and 78.3%; the PPV and NPV were 33.1% and 91.0%, respectively. Results were similar when equivocal ultrasound and negative appendectomies were excluded.

The high specificity and NPV suggest that ultrasound is a reliable test to exclude CA and an appendicolith in patients being considered for nonoperative management of simple appendicitis.

Computed tomography (CT) scanning reduces the negative appendectomy rate however it exposes the patient to ionizing radiation. Ultrasound (US) does not carry this risk but may be nondiagnostic. We hypothesized that a clinical-US scoring system would improve diagnostic accuracy.

We conducted a retrospective review of all patients (age, >15 years) who presented through the emergency department with suspected appendicitis and underwent initial US. A US score was developed using odds ratios for appendicitis given appendiceal diameter, compressibility, hyperemia, free fluid, and focal or diffuse tenderness. The US score was then combined with the Alvarado score. Final diagnosis of appendicitis was assigned by pathology reports.

Three hundred patients who underwent US as initial imaging were identified. Thirty-two patients with evident nonappendiceal pathology on US were excluded. In 114 (38%), the appendix was not visualized and partially visualized in 36 (12%). Fifty-seven (21.3%) had an appendectomy with 1 (1.7%) negative. Six nonvisualized appendicies underwent appendectomy, with no negative cases. Sensitivity and specificity for the sonographic score were 86% and 90%, respectively, at a score of 1.5. The combined score demonstrated 98% sensitivity and 82% specificity at 6.5, and 95% sensitivity, and 87% specificity at a score of 7.5. Sensitivity and specificity were confirmed by bootstrap resampling for validation. Area under receiver operating characteristic (ROC) curves for our new US score were similar to the ROC curve for the Alvarado score (91.9 and 91.1, p = 0.8). The combined US and Alvarado score yielded an area under the ROC curve of 97.1, significantly better than either score alone (p = 0.017 and p < 0.001, respectively).

Our scoring system based entirely on US findings was highly sensitive and specific for appendicitis, and it significantly improved when combined with the Alvarado score. After prospective evaluation, the combined US-Alvarado score might replace the need for computed tomography imaging in a majority of patients.

Diagnostic Test, Level III.

Our aim was to implement a standardized US report that included secondary signs of appendicitis (SS) to facilitate accurate diagnosis of appendicitis and decrease the use of computed tomography (CT) and admissions for observation.

A multidisciplinary team implemented a quality improvement (QI) intervention in the form of a standardized US report and provided stakeholders with monthly feedback. Outcomes including report compliance, CT use, and observation admissions were compared pretemplate and posttemplate.

We identified 387 patients in the pretemplate period and 483 patients in the posttemplate period. In the posttemplate period, the reporting of SS increased from 5.4% to 79.5% (p<0.001). Despite lower rates of appendix visualization (43.9% to 32.7%, p<0.001) with US, overall CT use (8.5% vs 7.0%, p=0.41) and the negative appendectomy rate remained stable (1.0% vs 1.0%, p=1.0). CT utilization for patients with an equivocal ultrasound and SS present decreased (36.4% vs 8.9%, p=0.002) and admissions for observations decreased (21.5% vs 15.3%, p=0.02). Test characteristics of RLQ US for appendicitis also improved in the posttemplate period.

A focused QI initiative led to high compliance rates of utilizing the standardized US report and resulted in lower CT use and fewer admissions for observation. Study of a Diagnostic Test Level of Evidence: 1.

An accurate diagnosis of acute appendicitis is important to avoid severe outcome or unnecessary surgery but management is controversial. The aim of study was to evaluate, in younger and older children, the efficacy of conservative management for uncomplicated appendicitis and the outcome of complicated forms underwent early surgery.

Children with acute appendicitis were investigated by clinical, laboratory variables and abdominal ultrasound and divided in two groups: complicated and uncomplicated. Complicated appendicitis underwent early surgery; uncomplicated appendicitis started conservative treatment with antibiotic. If in the next 24-48h it was worsening, the conservative approach failed and patients underwent late surgery.

A total of 362 pediatric patients were included. One hundred sixty-five underwent early appendectomy; 197 patients were at first treated conservatively: of these, 82 were operated within 24-48h for failure. The total percentage of operated patients was 68.2%. An elevated association was found between surgery and ultrasound.

Conservative treatment for uncomplicated appendicitis had high percentage of success (58%). Complications in operated patients were infrequent. Our protocol was effective in order to decide which patients treat early surgically and which conservatively; specific red flags (age and onset) can identified patients at most risk of complications or conservative failure.

treatment study.

II.

To evaluate the clinical relevance of the nonvisualized appendix on ultrasound imaging in children with right lower quadrant pain.

We reviewed 1359 children admitted for abdominal pain between January and December 2013 who had abdominal ultrasound imaging for right lower quadrant pain. Patients who had scans for genitourinary symptoms or intussusception were excluded from the study. When the appendix was not visualized, secondary signs indicating right lower quadrant inflammatory pathology were noted.

Of all admissions for abdominal pain, 810 had ultrasound scans. Thirty-eight did not evaluate the appendix and 131 were excluded for suspected intussusception, leaving 641 reports for children with a median age of 10.8 years (range, 1.3-21.3); 297 were boys (46.3%). There were 17 of 160 patients with a nonvisualized appendix (10.6%) who underwent appendectomy. Of these, 14 had secondary signs on ultrasound imaging and 3 (1.9%) had normal ultrasound reports. The 3 patients with normal ultrasound imaging had computed tomography imaging confirming appendicitis. There were 51 patients with a partially visualized appendix. The segment of appendix that could be seen was normal in 34 patients, none of whom had appendectomy. The remaining 17 had appendectomy, in whom the appendix seemed to be inflamed in 13 and equivocal in 4, all with histologically confirmed appendicitis. Overall, 232 children underwent appendectomy; 58 had no ultrasound imaging done, and 5 had a histologically normal appendix (overall negative appendectomy rate, 2.2%). Only 35 of 1359 patients (0.03%) had computed tomography scans.

In patients with a nonvisualized appendix on ultrasound imaging and no evidence of secondary inflammatory changes, the likelihood of appendicitis is less than 2%. Generous use of ultrasonography as an adjunct to clinical examination can achieve low negative appendectomy rates without underdiagnosis of acute appendicitis.

Concerns about radiation exposure have led to a decrease in the use of computed tomography in suspected appendicitis, with increased reliance on ultrasound. Children with suspected appendicitis should be risk stratified using a combination of clinical signs and symptoms, white blood cell count, and ultrasound in order to guide further evaluation and management. Magnetic resonance imaging is a promising imaging modality but remains costly. Ongoing research is evaluating the role of nonoperative management in children with confirmed appendicitis.

Ultrasound (US) is often the imaging modality of choice in women with acute right iliac fossa (RIF) pain, identifying the appendix in up to 99% of patients. The literature, however, lacks clear guidelines on how ultrasonography should be performed to maximise sensitivity and specificity in such patients. Many centres perform untargeted abdomino-pelvic scans, including organs such as the liver and spleen, which unlikely contribute to the presenting complaint.

We aimed to evaluate the clinical utility of unfocussed abdominal and pelvic US in women of reproductive age with acute RIF pain.

This multicentre study describes 501 women between the ages of 12 and 50, over a 3-year period from three institutions, presenting acutely with RIF pain and investigated with US abdomen and pelvis.

5.9% of cases confirmed appendicitis sonographically. A normal appendix was visualised in 0.2%. Over 10% identified gynaecological pathology, 41% relating to the right ovary. 10.4% incidental extra-pelvic findings were unrelated to the acute clinical presentation. 0.8% of patients had extra-pelvic findings meriting further clinical assessment.

The results herein reflect findings from high volume emergency surgical departments, demonstrating that unfocussed abdominal and pelvic ultrasounds are not an appropriate use of resources in reproductive women with RIF pain. Clinically relevant extra-pelvic US findings account for less than 1%, rarely contributing to the acute presentation. The appendix was only visualised in 6% of patients, suggesting that a focussed appendiceal and pelvic US would better assist diagnosis with a higher yield and increased sensitivity and specificity.

Ultrasound (US) is the preferred imaging modality for evaluating appendicitis. Our purpose was to determine if including secondary signs (SS) improve diagnostic accuracy in equivocal US studies.

Retrospective review identified 825 children presenting with concern for appendicitis and with a right lower quadrant (RLQ) US. Regression models identified which SS were associated with appendicitis. Test characteristics were demonstrated.

530 patients (64%) had equivocal US reports. Of 114 (22%) patients with equivocal US undergoing CT, those with SS were more likely to have appendicitis (48.6% vs 14.6%, p<0.001). Of 172 (32%) patients with equivocal US admitted for observation, those with SS were more likely to have appendicitis (61.0% vs 33.6%, p<0.001). SS associated with appendicitis included fluid collection (adjusted odds ratio (OR) 13.3, 95% confidence interval (CI) 2.1-82.8), hyperemia (OR=2.0, 95%CI 1.5-95.5), free fluid (OR=9.8, 95%CI 3.8-25.4), and appendicolith (OR=7.9, 95%CI 1.7-37.2). Wall thickness, bowel peristalsis, and echogenic fat were not associated with appendicitis. Equivocal US that included hyperemia, a fluid collection, or an appendicolith had 96% specificity and 88% accuracy.

Use of SS in RLQ US assists in the diagnostic accuracy of appendicitis. SS may guide clinicians and reduce unnecessary CT and admissions.