Introduction of appendiceal CT: impact on negative appendectomy and appendiceal perforation rates

Swedish national guidelines for diagnosis and management of acute appendicitis in adults and children

BACKGROUND

Acute appendicitis is one of the most common causes of acute abdominal pain. Differences in the management of this large group of patients has important consequences for the patients and the healthcare system. Controversies regarding the understanding of the natural course of the disease, the utility of new diagnostic methods, and alternative treatments have lead to large variations in practice patterns between centres. These national guidelines present evidence-based recommendations aiming at a uniform, safe and cost-efficient management of this large group of patients.

METHOD

A working group of six experts with broad clinical and research experience was formed. Additional expertise from outside was consulted during the process. A national survey revealed significant variations in the management of patients with suspicion of appendicitis. The evidence provided in published guidelines and reviews were extracted and systematically graded, according to the GRADE methodology. This was supplemented by additional more recent and more directed search of the literature. Patients treated for appendicitis were involved through interviews. The guidelines were reviewed by external experts before the final version was determined.

RESULTS

The guidelines cover an extensive number of issues: pathology, epidemiology, aetiology, natural history, clinical and laboratory diagnosis, diagnostic scoring systems, diagnostic imaging, treatment, nursing care, follow-up, quality registers and quality indicators, among others. Special considerations related to children and pregnant women are covered.

CONCLUSION

These national guidelines present an extensive and thorough review of the current knowledge base related to appendicitis, and provide up-to-date evidence-based recommendations for the management of this large group of patients.

Uncomplicated appendicitis at Herat Regional Hospital: limited resource is not always the end of the world

BACKGROUND

Acute appendicitis is the most common aetiology of acute abdomen in children. Our aim is to describe the accuracy of diagnosis, and complications in a limited resources setting in children between 5 and 14 years old at the only tertiary referral hospital in the West region of Afghanistan.

METHODS

A retrospective study for a period of 1 year (21 March 2015-20 March 2016). Data was collected from patients' files. Data were analysed by epi info 7.

RESULTS

We identified 774 children who had appendectomies at Herat Regional Hospital during the study period with complete records available for analysis. The median age was 11 years [5-14]. The rate of positive appendectomy was 87%. 72% of appendectomies were done within 24 h of the onset of symptoms. Of 675 positive appendectomies, the most common clinical features were migratory abdominal pain (90%), nausea/vomiting (80%), RLQ tenderness (90%), and rebound tenderness (81%). Among the 99 negative appendectomies, the most common signs and symptoms were anorexia 68%, nausea/vomiting 59%, RLQ tenderness 79%, and rebound tenderness 43%. 98% of positive and 71% of negative appendectomies had elevated WBC count. Post appendectomy complications occurred in 9% of our patients mostly commonly intra-abdominal abscesses (5%).

CONCLUSION

Although the diagnosis of acute appendicitis is challenging in children and may involve sophisticated imaging techniques, in many settings these are unavailable. Classical manifestations such as migratory abdominal pain, abdominal tenderness, nausea, and simple lab tests play a crucial role in the diagnosis of acute appendicitis in low resource environments.

Appendiceal neoplasms: Suspected findings and reports of 14 cases

Background

Neoplastic lesions of the vermiform appendix are still considered to be rare, some studies suggest that appendix cancer may be on the rise, with an estimated incidence of 0.08-0.1% of all appendiceal specimens. The lifetime incidence of malignant appendiceal tumors ranges from 0.2 to 0.5%.

Patients and Methods

Our study is applied at the Department of General Surgery at tertiary training and research hospital; 14 patients who had appendectomy or right hemicolectomy between December 2015 and April 2020 were evaluated.

Results

The mean age of the patients was 52.3 ± 15.1 (range, 26-79) years. Gender of the patients were: five (35.7%) men and nine (64.3%) women. The clinical diagnosis was appendicitis without suspected findings in 11 (78.6%), appendicitis with suspected findings (appendiceal mass, etc.) in three (21.4%) of the patients, and there is no patient with asymptomatic or other rare findings. Surgeries applied for the patients were: nine (64.3%) underwent open appendectomy, four (28.6%) underwent laparoscopic appendectomy, and one (7.1%) underwent open right hemicolectomy. Histopathologic results were as follows: five (35.7%) neuroendocrine neoplasm, eight (57.1%), noninvasive mucinous neoplasm, and one (7.1%) adenocarcinoma.

Conclusion

While diagnosis and management of appendiceal pathology, surgeons should be familiar with suspected findings of appendiceal tumors and discuss them with patients to the possibility of histopathologic results.

Routine Computed Tomography Versus Selective Imaging: An Audit of Negative Appendicectomy Rates in Two Hospitals

Introduction There are a variety of conflicting recommendations in the literature for pre-operative imaging in acute appendicitis. There is debate over what the ideal imaging protocol is to lower the negative appendicectomy rate (NAR) without increasing missed appendicitis. The aim of this study is to compare the audited NAR between two groups with different imaging approaches: (i) mandatory pre-operative computed tomography (CT) imaging and (ii) selective imaging with CT, ultrasound (US), or no imaging prior to appendicectomy. Materials and methods A retrospective chart audit was conducted of 400 patients who underwent an appendicectomy at two hospitals with different approaches to pre-operative imaging (hospital A and hospital B). The primary outcome measure was histologically confirmed appendicitis. It was also documented whether there was radiological (CT or US) evidence of appendicitis.  Results At hospital A, all 200 patients underwent CT imaging prior to appendicectomy. The total histologically confirmed NAR for this group was 9.5% (19/200). At hospital B, 97 (48.5%) patients underwent CT, 41 (25.5%) underwent US, 10 (5%) had both US and CT, and 52 (26%) had no imaging. The total NAR was 11.5% (23/200). Conclusion There was no statistically significant difference (p=0.62) in audited NARs when comparing clinician-guided selective imaging versus routine CT imaging for all patients undergoing appendicectomy.

Negative appendectomy rate in patients diagnosed with acute appendicitis

BACKGROUND

Acute appendicitis is the most common cause of acute lower abdominal pain leading patients to the emergency department. This study aims to find the negative appendectomy rate in patients diagnosed with acute appendicitis from 2015 to 2019.

METHODS

This study was a retrospective cohort study in the patients preoperatively diagnosed with acute appendicitis and underwent appendectomy from January 2015 to December 2019. Negative appendectomy is defined as the final pathologic results confirmed normal, congestion or peri-appendicitis.

RESULTS

The study population was 892 patients which was 54.3% female. The five-year negative appendectomy rate was 8.6% (n = 77) and 70% in female (n = 54). The factors associated with increasing the negative appendectomy rate were female (OR 2.23, P = 0.003), age ≤ 40 years old (OR 2.35, P = 0.003), and no history of diarrhea (OR 2.42, P = 0.017). Whereas the factors related to decline in the negative appendectomy rate were white blood cell count (WBC) [Formula: see text] 10,000 (OR 0.39, P = 0.016), neutrophil (N) [Formula: see text] 75% (OR 0.28, P < 0.001), and positive appendicitis from ultrasonography of abdomen (OR 0.04, P < 0.001) or computed tomography of abdomen (OR 0.07, P < 0.001).

CONCLUSION

The negative appendectomy rate was less than 10% in this study. Female, age 40 ≤ years old and history of diarrhea were related to increase in negative appendectomy. The factors that related to decline in negative appendectomy were leukocytosis with cells shift to the left, positive acute appendicitis from abdominal ultrasonography and CT scan. However, to request the further imaging studies to diagnose patients with suspected acute appendicitis depends on the risk and benefit to each patient and the choice of investigation.

Management of acute appendicitis during the COVID-19 pandemic: a retrospective cohort study

BACKGROUND

The Coronavirus Disease 2019 (COVID-19) pandemic profoundly impacted delivery of health care. South Western Sydney Local Health District (SWSLHD) experienced some of the highest cases, admissions and deaths during the Delta and Omicron waves in New South Wales. This study aims to determine the impact of the pandemic on emergency surgery services for adults presenting with acute appendicitis.

METHODS

A retrospective review of patient records was performed of adults presenting with acute appendicitis between 1st March 2021 and 31st March 2022, which was compared to a pre-COVID control period of the same dates in 2019-2020. Patients managed operatively or conservatively were included.

RESULTS

1556 patients were included in the operative arm; 723 and 833 respectively in the study and control groups, which were comparable at baseline. 1.66% were COVID positive. During the pandemic, patients were significantly more likely to be investigated with computered tomography (CT) scan (p ≤ 0.001), present with complicated appendicitis (p = 0.03), and require caecectomy (p = 0.005). They had higher American Society of Anaesthesiology (ASA) scores (p = 0.001) and significantly lower negative appendectomy rates (p = 0.001). Fifty-two patients were included in the conservative arm; 29 and 23 respectively in the pandemic and control groups. Patients were comparable at baseline. There were two COVID positive patients. During the pandemic, there was a significant reduction in complications (p = 0.033), readmissions (0.044) and interval appendicectomy (p = 0.0044).

CONCLUSION

We identified higher rates of complicated appendicitis, caecectomies and greater reliance on CT imaging preoperatively during the pandemic in SWSLHD.

Left-sided appendicitis due to anatomical variation: A case report

Introduction

Left-sided appendicitis is a rare condition, and we report a patient with left abdominal heterotopia of the right colon complicated by acute appendicitis in the left lower quadrant.

Case presentation

A 39-year-old male was admitted to hospital following left lower abdominal pain for 1 day. Imaging examination by abdominal CT showed that the appendix was not clearly seen, and a mass was found in the left lower abdomen. Because the patient's abdominal pain was severe and the current diagnosis was not clear, after soliciting the patient's consent, we performed laparoscopic exploration. This exploration revealed that the cecum and ascending colon were located in the left iliac fossa, the appendix was swollen, the length of the appendix was approximately 6 cm, the diameter of the appendix was approximately 1 cm, and there was pus moss attached to the surface. We performed a laparoscopic appendectomy; the procedure was uneventful and the patient was discharged 3 days after the procedure.

Conclusion

Left-sided appendicitis is a rare condition and is therefore easy to misdiagnose. Wrong diagnosis can lead to serious complications and endanger the patient's life. Therefore, a full combination of laboratory tests and CT scan is required. If still no diagnosis can be made correctly, a laparoscopic exploration needs to be performed in a timely manner. This case teaches us that when we encounter a patient with severe left abdominal pain that cannot be definitely diagnosed, we need to be vigilant and perform timely laparoscopic exploration when necessary.

DIAgnostic iMaging or Observation in early equivocal appeNDicitis (DIAMOND): open-label, randomized clinical trial

BACKGROUND

Mild appendicitis may resolve spontaneously. The use of CT may lead to an overdiagnosis of uncomplicated appendicitis. The aims of this study were to examine whether early imaging results in more patients being diagnosed with acute appendicitis than initial observation, and to study the safety and feasibility of score-based observation compared with imaging in patients with equivocal signs of appendicitis.

METHODS

Patients with suspected appendicitis with symptoms for fewer than 24 h and an Adult Appendicitis Score of 11-15 were eligible for this trial. After exclusions, patients were randomized openly into two equal-sized groups: imaging and observation. Patients in the imaging group had ultrasound imaging followed by CT when necessary, whereas those in the observation group were reassessed after 6-8 h with repeated scoring and managed accordingly. The primary outcome was the number of patients requiring treatment for acute appendicitis within 30 days.

RESULTS

Ninety-three patients were randomized to imaging and 92 to observation; after exclusions, 93 and 88 patients respectively were analysed. In the imaging group, more patients underwent treatment for acute appendicitis than in the observation group: 72 versus 57 per cent (difference 15 (95 per cent c.i. 1 to 29) per cent). This suggests that patients with spontaneously resolving appendicitis were not diagnosed or treated in the observation group. Some 55 per cent of patients in the observation group did not need diagnostic imaging within 30 days after randomization. There was no difference in the number of patients diagnosed with complicated appendicitis (4 versus 2 per cent) or negative appendicectomies (1 versus 1 per cent) in the imaging and observation groups.

CONCLUSION

Score-based observation of patients with early equivocal appendicitis results in fewer patients requiring treatment for appendicitis. Registration number: NCT02742402 (http://www.clinicaltrials.gov).

Diagnosis of acute appendicitis based on clinical scores: is it a myth or reality?

Background and aim of the work In April 2020, the World Society of Emergency Surgery (WSES) published the first update to the Jerusalem Guidelines on the diagnosis and treatment of acute appendicitis. In this review we have reported a summary of the contemporary evidence from the literature that led to the guidelines statements on the diagnostic strategies for appendicitis. Methods A systematic literature search was performed for studies published on the use of the most common clinical scores and imaging for the diagnosis of appendicitis. Results Alvarado, AIR and AAS scores are sufficiently sensitive (up to 99%) to exclude appendicitis, accurately identifying low-risk patients and decreasing the need for imaging and the negative appendectomy rates in such patients. Conversely, for young patients deemed to be at high-risk of appendicitis according to the scores, because of the high prevalence of the disease in this group of patients (~90%), a negative imaging scan cannot rule out appendicitis. The sensitivity and specificity of CT is reported at 0.91-0.94 and 0.90-0.95. The corresponding results for US are 0.78-0.88 and 0.81-0.94, respectively. Conclusions In young patients, a high-probability score for appendicitis may be used to select patients in which imaging is not needed. When the surgeon deems diagnostic imaging is still needed to confirm appendicitis despite the patient has been scored at high-risk, a conditional CT scan strategy is advised, with CT scan performed only after a negative or equivocal ultrasound scan.

Computerized tomography scan in acute appendicitis with eventual negative appendectomy

Background and Aim:

Acute appendicitis (AA) is traditionally considered a clinical diagnosis and negative appendectomy (NA) rates vary across health-care systems. Computed tomography (CT) scans have been shown to aid in the reduction of NA rates. Our study aimed to determine the pre-operative imaging characteristics in patients undergoing appendectomy with eventual normal histology.

Materials and Methods:

An audit of all patients with a discharge diagnosis of AA was conducted from January 2011 to December 2015. Histology reports of all patients who underwent appendectomies were reviewed, and medical records of patients with NA were included in the study. To study the impact of CT scan reporting in NA patients, CT scan images of patients with NA were reviewed retrospectively by two blinded radiologists.

Results:

A total of 2603 patients underwent appendectomy for suspected AA, and NA rate was 3.34% (n=87). The mean age of patients with NA was 30.3 (14.8-69.8) years with no gender difference (51.7% male). Sixty-six (75.9%) patients had laparoscopic appendectomy with 3.5% open conversion rate. CT scans were done in 47 patients. Pre-operative CT scan report was more likely to report dilated appendix (n=26 [55.3%] vs. n=7 [14.9%], P=0.0001). Post-operative blinded radiology review was more like to report other pathology (n=27 [57.4%] vs. n=2 [4.3%], P=0.0001) and normal appendix (n=26 [55.3%] vs. n=5 (10.6%), P=0.0001).

Conclusion:

The NA rate is low. There needs to be standardized reporting for imaging features of prominent/dilated appendix.

Relevance for Patients:

Appendectomy must be avoided in patients with a normal CT scan and when another pathological diagnosis is established. Liberal imaging policy assists to reduce NA rates. Imaging features of prominent or dilated appendix can be subjective and international collaboration is needed to define thresholds for imaging diagnosis of AA.

Reference growth curves for normal appendiceal diameter in childhood

The aim of this study was to investigate the relationship between the appendiceal diameter (AD) and age, sex, height, and body weight in children and to verify how does the normal AD grows in childhood. We evaluated the AD of patients younger than 16 years of age who underwent laparoscopic surgery at our hospital. We statistically examined the relationship between the AD and the age, sex, height, and weight. A final cohort of 188 patients participated in the study. The median AD for the sample population was 5 mm (range, 3.2–8.1). There was no significant difference in the AD between males and females in the multivariate analysis (P = 0.500). There was a positive correlation between the age and the AD (R = 0.396, P < 0.001). The AD had a significant positive correlation with the height and weight (P < 0.001, P < 0.001, respectively). The reference curve with regard to the AD can be useful in clinical situations, although it should be kept in mind that the range of individual differences in AD is large, and the growth degree by age is not uniform during childhood.

Accuracies of Diagnostic Methods for Acute Appendicitis

The objectives were to evaluate the effectiveness of ultrasonography, computed tomography, and physical examination for diagnosing acute appendicitis with analyzing their accuracies and negative appendectomy rates in a clinical rather than research setting. A total of 2763 subjects were enrolled. Sensitivity, specificity, positive predictive value, and negative predictive value and negative appendectomy rate for ultrasonography, computed tomography, and physical examination were calculated. Confirmed positive acute appendicitis was defined based on pathologic findings, and confirmed negative acute appendicitis was defined by pathologic findings as well as on clinical follow-up. Sensitivity, specificity, positive predictive value, and negative predictive value for ultrasonography were 99.1, 91.7, 96.5, and 97.7 per cent, respectively; for computed tomography, 96.4, 95.4, 95.6, and 96.3 per cent, respectively; and for physical examination, 99.0, 76.1, 88.1, and 97.6 per cent, respectively. The negative appendectomy rate was 5.8 per cent (5.2% in the ultrasonography group, 4.3% in the computed tomography group, and 12.2% in the physical examination group). Ultrasonography/computed tomography should be performed routinely for diagnosis of acute appendicitis. However, in view of its advantages, ultrasonography should be performed first. Also, if the result of a physical examination is negative, imaging studies after physical examination can be unnecessary.

Suspected appendicitis pathway continues to lower CT rates in children two years after implementation

BACKGROUND

We implemented a protocol to evaluate pediatric patients with suspected appendicitis using ultrasound as the initial imaging modality. CT utilization rates and diagnostic accuracy were evaluated two years after pathway implementation.

METHODS

This was a retrospective observational study of patients <18 years evaluated for suspected appendicitis. CT rates were compared before and after implementation of the protocol, and monthly CT rates were calculated to assess trends in CT utilization.

RESULTS

CT use decreased significantly following pathway implementation from 94.2% (130/138) to 27.5% (78/284; p < 0.001). Linear regression of monthly CT utilization demonstrated that CT rates continued to trend down two years after pathway implementation. Adherence to the pathway was 89.8% (255/284). Negative appendectomy rate was 2.4% (2/85) in the post-pathway period.

CONCLUSIONS

Adherence to a pathway designed to evaluate pediatric patients with suspected appendicitis using ultrasound as the primary imaging modality has led to a sustained decrease in CT use without compromising diagnostic accuracy.

Focused CT for the evaluation of suspected appendicitis

PURPOSE

To determine the diagnostic accuracy of focused appendiceal CT as a feasible alternative to the standard CT of the abdomen and pelvis (CT-AP) in patients with suspected acute appendicitis.

METHODS

Retrospective review of 200 adults with suspected acute appendicitis between January and October 2016 were included in this study. Each patient underwent CT-AP with oral and intravenous (IV) contrast. A subset of axial images starting at the top of L4 vertebral body to the roof of the acetabula were obtained from each study which served as the focused appendiceal CT. After review of the focused CTs, the non-focused CT-AP scans were reviewed, each patient acting as their own control. Images were assessed for ability to identify the appendix, assess for appendicitis, or identify alternative diagnoses that could account for the presenting symptoms.

RESULTS

Of 200 cases, the appendix was visualized in the focused CT in 191 patients. In nine studies, the appendix was not visualized in focused or standard CT-AP. Using focused CT, 42 cases were positive for acute appendicitis. This result was identical when reviewing standard CT-AP. Alternative diagnoses were present in 38 patients. Using focused CT, 14 of these were not fully covered but the readers were able to make the diagnoses confidently on the focused CTs. Only one patient had acute non-appendiceal pathology mostly outside of the field of view.

CONCLUSIONS

Focused appendiceal CT with IV and oral contrast in the setting of clinically suspected appendicitis is a suitable alternative to conventional CT-AP.

Accuracy and reliability of tablet computer as an imaging console for detection of radiological signs of acute appendicitis using PACS workstation as reference standard

PURPOSE

To ascertain the accuracy and reliability of tablet as an imaging console for detection of radiological signs of acute appendicitis [on focused appendiceal computed tomography (FACT)] using Picture Archiving and Communication System (PACS) workstation as reference standard.

METHODS

From January, 2014 to June, 2015, 225 patients underwent FACT at our institution. These scans were blindly re-interpreted by an independent consultant radiologist, first on PACS workstation and, two weeks later, on tablet. Scans were interpreted for the presence of radiological signs of acute appendicitis. Accuracy of tablet was calculated using PACS as reference standard. Kappa (κ) statistics were calculated as a measure of reliability.

RESULTS

Of 225 patients, 99 had radiological evidence of acute appendicitis on PACS workstation. Tablet was 100% accurate in detecting radiological signs of acute appendicitis. Appendicoliths, free fluid, lymphadenopathy, phlegmon/abscess, and perforation were identified on PACS in 90, 43, 39, 10, and 12 scans, respectively. There was excellent agreement between tablet and PACS for detection of appendicolith (к = 0.924), phlegmon/abscess (к = 0.904), free fluid (к = 0.863), lymphadenopathy (к = 0.879), and perforation (к = 0.904).

CONCLUSIONS

Tablet computer, as an imaging console, was highly reliable and was as accurate as PACS workstation for the radiological diagnosis of acute appendicitis.

Diagnostic Efficiency of Multidetector Computed Tomography in the Evaluation of Clinically Equivocal Cases of Acute Appendicitis with Surgical Correlation

Acute appendicitis is one of the most frequent causes of lower abdominal pain and requires immediate surgical intervention. The diagnosis often poses a lot of challenge even to experienced surgeon. Those patients with equivocal symptoms may require different imaging modalities like radiography, contrast examination and ultrasound with limited utility. Multidetector computed tomography (MDCT) used in suspected acute appendicitis has, however, resulted in improved diagnostic accuracy and also reduction of negative surgeries. Objective We intend to determine the diagnostic efficiency of MDCT in clinically equivocal cases of acute appendicitis correlating it with surgical/histopathological findings. Materials and methods A group of 116 patients was included in this study. Spiral MDCT was performed in all these cases after administration of oral and intravenous contrast. All these patients underwent surgery and the CT findings were correlated with histopathology. Out of these 116 patients, 60 patients were male and 56 female. The age range was from three to seventy years and mean age was 28+1 years. Results The results proved that MDCT had a sensitivity of 97.5%, specificity of 97.0%, and accuracy of 97.4% for the diagnosis of appendicitis with one false positive and two false negative cases. The study showed 100% accuracy in diagnosing acute appendicitis in children. In 33 patients, an alternate cause was identified with CT. The alternate diagnosis made on CT findings was consistent with the final diagnosis in 27 (81.8%) of 33 patients in whom there was no evidence of acute appendicitis. The clinical diagnosis disagreed with the CT diagnosis in six patients (18.18%). Conclusion Our study verifies that MDCT plays an important role in evaluation and consequent management of equivocal cases of acute appendicitis. MDCT is also able to diagnose appendicitis or detect alternative diagnosis in pediatric population.

Single-center analysis of appendiceal neoplasms

The purpose of the present study was to evaluate the recent trend of diagnosing appendiceal diseases through the analysis of appendectomy materials, stressing the importance of their pathological examination. A clinicopathological assessment of patients undergoing an appendectomy was conducted, based on the pathological examination of resected appendiceal lesions. Using a pathological database of surgical specimens from patients who underwent an appendectomy between March 2002 and September 2014, a retrospective, single-center analysis was performed. Among the 803 patients identified, 752 with appendiceal disease were selected for clinicopathological analysis. The diagnosis was inflammation (i.e. appendicitis) in 97.7% (n=735) and appendiceal neoplasm in 2.3% (n=17) of the patients. The most frequent type of appendiceal neoplasm was an intramucosal neoplasm (23.5%, n=4). In conclusion, the incidence of appendiceal neoplasms has increased in recent years, potentially due to increased and earlier detection by newer imaging modalities.

A prospective non-randomized controlled, multicenter trial comparing Appendectomy and Conservative Treatment for Patients with Uncomplicated Acute Appendicitis (the ACTUAA study)

PURPOSE

Acute appendicitis (AA) is among the most common causes of lower abdominal pain and admissions to the emergency department. Over the past 20 years, there has been a renewed interest in the conservative management of uncomplicated AA, and several studies demonstrated that an antibiotic-first strategy is a viable treatment option for uncomplicated AA. The aim of this prospective non-randomized controlled, multicenter trial is to compare antibiotic therapy and emergency appendectomy as treatment for patients with uncomplicated AA confirmed by US and/or CT or MRI scan.

METHODS

All adult patients in the age range 18 to 65 years with suspected AA, consecutively admitted to the Surgical Department of the 13 participating Italian Hospitals, will be invited to take part in the study. A multicenter prospective collected registry developed by surgeons, radiologists, and pathologists with expertise in the diagnosis and treatment of uncomplicated acute appendicitis represents the best research method to assess the long-term role of antibiotics in the management of the disease. Comparison will be made between surgical and antibiotic-first approaches to uncomplicated AA through the analysis of the primary outcome measure of complication-free treatment success rate based on 1-year follow-up. Quality of life, length of hospital stay, pain evaluation, and time to return to normal activity will be evaluated as secondary outcome measures.

TRIAL REGISTRATION

Clinicaltrials.gov ID: NCT03080103.

The Accuracy of the Computed Tomography Diagnosis of Acute Appendicitis: Does the Experience of the Radiologist Matter?

Background and Aims:

To assess the accuracy of computed tomography in diagnosing acute appendicitis with a special reference to radiologist experience.

Material and Methods:

Data were collected prospectively in our randomized controlled trial comparing surgery and antibiotic treatment for uncomplicated acute appendicitis (APPAC trial, NCT01022567). We evaluated 1065 patients who underwent computed tomography for suspected appendicitis. The on-call radiologist preoperatively analyzed these computed tomography images. In this study, the radiologists were divided into experienced (consultants) and inexperienced (residents) ones, and the comparison of interpretations was made between these two radiologist groups.

Results:

Out of the 1065 patients, 714 had acute appendicitis and 351 had other or no diagnosis on computed tomography. There were 700 true-positive, 327 true-negative, 14 false-positive, and 24 false-negative cases. The sensitivity and the specificity of computed tomography were 96.7% (95% confidence interval, 95.1–97.8) and 95.9% (95% confidence interval, 93.2–97.5), respectively. The rate of false computed tomography diagnosis was 4.2% for experienced consultant radiologists and 2.2% for inexperienced resident radiologists (p = 0.071). Thus, the experience of the radiologist had no effect on the accuracy of computed tomography diagnosis.

Conclusion:

The accuracy of computed tomography in diagnosing acute appendicitis was high. The experience of the radiologist did not improve the diagnostic accuracy. The results emphasize the role of computed tomography as an accurate modality in daily routine diagnostics for acute appendicitis in all clinical emergency settings.

Performance of imaging studies in patients with suspected appendicitis after stratification with adult appendicitis score

Background

Diagnostic scoring is used to stratify patients with suspected appendicitis into three groups: high, intermediate, and low probability of appendicitis. The stratification can be used for selective imaging to avoid the harms of radiation without compromising diagnostic accuracy.

The aim was to study how stratification by Adult Appendicitis Score affects diagnostic performance of imaging studies.

Methods

Analysis of 822 patients who underwent diagnostic imaging for suspected appendicitis was made. Adult Appendicitis Score was used to stratify patients into groups of high, intermediate, and low probability of appendicitis. Diagnostic performance of computed tomography (CT) and ultrasound (US) was compared between these patient groups.

Results

After scoring, pre-test probability of appendicitis ranged from 9-16% in low probability group to 75-79% in high probability group in patients who underwent US or CT. Post-test probability of appendicitis after positive CT was 99, 91, and 75% in high probability, intermediate probability and low probability groups, respectively, p < 0.001. After positive US the respective probabilities were 95, 91 and 42%, p < 0.001.

Conclusion

Diagnostic imaging has limited value in patients with low probability of appendicitis according to Adult Appendicitis Score.

Comparison of US and CT on the effect on negative appendectomy and appendiceal perforation in adolescents and adults: A post-hoc analysis using propensity-score methods

PURPOSE

To retrospectively compare ultrasound (US) and CT as the preoperative first-line imaging modality in terms of negative appendectomy rate (NAR) and appendiceal perforation rate (APR) in adolescents and adults with suspected appendicitis.

METHODS

We included 2,030 patients in 11 sites who underwent appendectomy following US (n = 102) or CT (n = 1,928). Propensity-score (PS) adjusted and matched comparisons were conducted. Matching was performed with 1:1 and 1:3 ratios. Secondary analyses were performed by adding appendiceal perforation to PS model.

RESULTS

The unadjusted NAR difference between the unmatched US and CT groups (8% [8/102] versus 3.8% [73/1,928]) was 4.1 percentage points (95% confidence interval, -1.2, -9.3; p = 0.133). The PS adjusted difference was 4.1 percentage points (-1.8, -10.0; p = 0.169). The differences after 1:1 (9% [8/94] versus 5% [5/94]) and 1:3 (9% [8/94] versus 3.0% [8/271]) matching were 3 (-4, -10, p = 0.39) and 5.6 (-0.4, -11.6, p = 0.069) percentage points, respectively. The unadjusted APR difference between the unmatched US and CT groups (22% [22/102] versus 23.8% [459/1,928]) was -2.2 percentage points (-10.4, -6.0; p = 0.59). The PS-adjusted difference was -5.2 percentage points (-13.3, -2.9; p = 0.21). The differences after 1:1 (19% [18/94] versus 24% [23/94]) and 1:3 (19% [18/94] versus 20.7% [56/271]) matching were -5 (-17, -6, p = 0.38) and -1.5 (-10.8, -7.8, p = 0.75) percentage points, respectively.

CONCLUSIONS

The use of US instead of CT may increase NAR but does not significantly affect APR. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:401-410, 2016.

Intravenous and Oral Contrast vs Intravenous Contrast Alone Computed Tomography for the Visualization of Appendix and Diagnosis of Appendicitis in Adult Emergency Department Patients

Purpose

The study sought to compare radiologist's ability to 1) visualize the appendix; 2) diagnose acute appendicitis; and 3) diagnose alternative pathologies responsible for acute abdominal pain among adult patients undergoing computed tomography (CT) scan with 3 different protocols: 1) intravenous (IV) contrast only; 2) IV and oral contrast with 1-hour transit time; and 3) IV and oral contrast with 3-hour transit time.

Methods

We collected data of 225 patients; 75 consecutive patients with a clinical suspicion of appendicitis received oral contrast for 3 hours and IV contrast, 75 received oral contrast for 1 hour and IV contrast, and 75 trauma patients received IV contrast only. Three independent reviewers, blinded to final pathology, retrospectively analysed the cases and documented visualization of the appendix, periappendiceal structures, and their confidence in diagnosing appendicitis. Clinical diagnoses were derived from a combination of clinical, surgical, pathologic, or radiologic follow-up.

Results

Frequency of visualizing the appendix within IV group alone was 87.3%, IV with oral for 1 hour was 94.1%, and IV with oral for 3 hours was 93.8%. Both oral contrast groups had 100% sensitivity and negative predictive value in diagnosis of acute appendicitis. Specificity for the 1- and 3-hour oral contrast groups was 94.1% and 96.1%, respectively and positive predictive value for both groups was 92%.

Conclusions

Our findings suggest that reader confidence in visualizing the appendix improved with addition of oral contrast as compared to IV contrast alone. One- and 3-hour oral regimens have a similar diagnostic performance in diagnosing appendicitis.

Should Oral Contrast Be Omitted in Patients with Suspected Appendicitis?

BACKGROUND

Acute appendicitis is one of the most common surgical emergencies. Our study evaluated patients given the diagnosis of appendicitis and reviewed their workup and clinical outcomes. We specifically focused on the use of oral contrast followed by appendectomy.

METHODS

We retrospectively reviewed all adult patients given an ICD-9 code for appendicitis at Northwestern Memorial Hospital between January 2000 and September 2010. Complication rates, time to the operating room, and length of hospital stay were compared between patients who received a CT scan and those who did not during the hospitalization for appendicitis.

RESULTS

Average time from Emergency Department to the operating room was found to be statistically longer for patients who underwent a CT scan (10 h: 3, 1548) versus those who did not (6 h: 2, 262) (p < 0.0001). There were 19 patients who had the complication of pneumonia and 4 patients who were diagnosed with acute respiratory distress syndrome postoperatively. Patients who underwent a CT scan and received oral contrast had a statistically higher number of both complications (p < 0.0001).

CONCLUSIONS

The use of oral contrast is not necessary for an accurate diagnosis of appendicitis and may be associated with higher complication rates, longer hospital stays, and poor outcomes.

Imaging in acute appendicitis: What, when, and why?

Acute appendicitis (AA) is the commonest cause of pain abdomen requiring surgical intervention. Diagnosis as well as management of acute appendicitis is mired in controversies and contradictions even today. Clinicians often face the dilemma of balancing negative appendectomy rate and perforation rate if the diagnosis is based on clinical scoring alone. Laboratory results are often non-specific. Imaging has an important role not only in diagnosing appendicitis and its complication but also suggesting alternate diagnosis in appropriate cases. However, there is no universally accepted diagnostic imaging algorithm for appendicitis. Imaging of acute appendicitis needs to be streamlined keeping pros and cons of the available investigative modalities. Radiography has practically no role today in the diagnosis and management of acute appendicitis. Ultrasonography (USG) should be the first line imaging modality for all ages, particularly for children and non-obese young adults including women of reproductive age group. If USG findings are unequivocal and correlate with clinical assessment, no further imaging is needed. In case of equivocal USG findings or clinico-radiological dissociation, follow-up/further imaging (computed tomography (CT) scan/magnetic resonance imaging (MRI)) is recommended. In pediatric and pregnant patients with inconclusive initial USG, MRI is the next option. Routine use of CT scan for diagnosis of AA needs to be discouraged. Our proposed version of a practical imaging algorithm, with USG first and always has been incorporated in the article.

Meta-analysis of antibiotics versus appendicectomy for non-perforated acute appendicitis

Background

For more than a century, appendicectomy has been the treatment of choice for appendicitis. Recent trials have challenged this view. This study assessed the benefits and harms of antibiotic therapy compared with appendicectomy in patients with non‐perforated appendicitis.

Methods

A comprehensive search was conducted for randomized trials comparing antibiotic therapy with appendicectomy in patients with non‐perforated appendicitis. Key outcomes were analysed using random‐effects meta‐analysis, and the quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

Results

Five studies including 1116 patients reported major complications in 25 (4·9 per cent) of 510 patients in the antibiotic and 41 (8·4 per cent) of 489 in the appendicectomy group: risk difference −2·6 (95 per cent c.i. –6·3 to 1·1) per cent (low‐quality evidence). Minor complications occurred in 11 (2·2 per cent) of 510 and 61 (12·5 per cent) of 489 patients respectively: risk difference −7·2 (−18·1 to 3·8) per cent (very low‐quality evidence). Of 550 patients in the antibiotic group, 47 underwent appendicectomy within 1 month: pooled estimate 8·2 (95 per cent c.i. 5·2 to 11·8) per cent (high‐quality evidence). Within 1 year, appendicitis recurred in 114 of 510 patients in the antibiotic group: pooled estimate 22·6 (15·6 to 30·4) per cent (high‐quality evidence). For every 100 patients with non‐perforated appendicitis, initial antibiotic therapy compared with prompt appendicectomy may result in 92 fewer patients receiving surgery within the first month, and 23 more experiencing recurrent appendicitis within the first year.

Conclusion

The choice of medical versus surgical management in patients with clearly uncomplicated appendicitis is value‐ and preference‐dependent, suggesting a change in practice towards shared decision‐making is necessary.

Limitations of each evolving

ACR Appropriateness Criteria® Right Lower Quadrant Pain--Suspected Appendicitis

The most common cause of acute right lower quadrant (RLQ) pain requiring surgery is acute appendicitis (AA). This narrative's focus is on imaging procedures in the diagnosis of AA, with consideration of other diseases causing RLQ pain. In general, Computed Tomography (CT) is the most accurate imaging study for evaluating suspected AA and alternative etiologies of RLQ pain. Data favor intravenous contrast use for CT, but the need for enteric contrast when intravenous contrast is used is not strongly favored. Radiation exposure concerns from CT have led to increased investigation in minimizing CT radiation dose while maintaining diagnostic accuracy and in using algorithms with ultrasound as a first imaging examination followed by CT in inconclusive cases. In children, ultrasound is the preferred initial examination, as it is nearly as accurate as CT for the diagnosis of AA in this population and without ionizing radiation exposure. In pregnant women, ultrasound is preferred initially with MRI as a second imaging examination in inconclusive cases, which is the majority.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Trends in the Diagnosis and Management of Pediatric Appendicitis

• On the basis of class B evidence and consensus, acute appendicitis in children can often be diagnosed clinically with only selective use of imaging. (13)(14)(15)(16) • On the basis of class B evidence and consensus, ultrasonography is the test of choice when acute appendicitis is suspected but is unclear based on history, physical examination, and laboratory results. (17)(18)(19) • On the basis of class B evidence and consensus, the use of computed tomography scan should be limited to cases of suspected complex appendicitis with abscess or when there is clinical suspicion for acute appendicitis but ultrasonography results are not helpful. (16) • On the basis of class C evidence and consensus, children with possible appendicitis ideally should be treated in medical centers that have skilled sonographic personnel. (21) • On the basis of class B evidence and consensus, simple appendicitis should be treated by appendectomy during normal operating hours. Preoperative treatment with intravenous antibiotics and fluids during the overnight hours halts disease progression and allows for the safest surgery with the benefit of a full and rested staff. (24)(25)(26) • On the basis of class B evidence and consensus, complex appendicitis with a well-defined abscess can be treated nonoperatively initially, with the option of an interval appendectomy after recovery from the acute infection. (29)(30) (31)(32)(33)

Magnetic resonance imaging of acute appendicitis in pregnancy: a 5-year multiinstitutional study

OBJECTIVE

The purpose of this study was to determine the diagnostic performance of magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis during pregnancy in a multiinstitutional study.

STUDY DESIGN

In this multicenter retrospective study, the cases of pregnant women who underwent MRI evaluation of abdominal or pelvic pain and who had clinical suspicion of acute appendicitis between June 1, 2009, and July 31, 2014, were reviewed. All MRI examinations with positive findings for acute appendicitis were confirmed with surgical pathologic information. Sensitivity, specificity, negative predictive values, and positive predictive values were calculated. Receiver operating characteristic curves were generated, and area under the curve analysis was performed for each participating institution.

RESULTS

Of the cases that were evaluated, 9.3% (66/709) had MRI findings of acute appendicitis. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive values were 96.8%, 99.2%, 99.0%, 92.4%, and 99.7%, respectively. There was no statistically significant difference between centers that were included in the study (pair-wise probability values ranged from 0.12-0.99).

CONCLUSION

MRI is useful and reproducible in the diagnosis of suspected acute appendicitis during pregnancy.

Histopathological correlations of appendectomies: a clinical audit of a single center

BACKGROUND

Acute appendicitis is a common presentation in surgical assessment units and appendectomy accounts for a large number of emergency operations in the UK. Histopathological examination of the appendectomy specimens are routinely carried out. The aim of this study is to correlate the histological findings of appendectomy specimens with the clinical diagnosis of acute appendicitis.

METHODS

This is a retrospective analysis of 238 appendectomies carried out in a single UK center between January and December 2013. The Histopathology reports of appendectomy specimens were retrieved.

RESULTS

A total of 238 appendectomies were performed during the study period. The mean age of the patients was 32 years (range, 7-81 years). Adult patients (>16 years) represented 79.4% of the study population. The female sex accounted for 46.6% of all the patients. Of the 238 resected appendix, 211 (88.7%) had histopathology findings consistent with appendicitis. Approximately 1.7% of the 238 specimens were abnormal pathologies other than inflammation of the appendix. The negative appendectomy (normal appendix on histology) rate was 11.3%. The female sex accounted for 59.1% of the negative appendectomies. Adults (>16 years) represented 77.8% of the negative appendectomies.

CONCLUSIONS

The observed high rates of negative appendectomy in the female sex can be reduced by utilizing combined clinical assessment and diagnostic imaging modalities. The findings of abnormal pathologies on histopathological examination of the appendix which could potentially impact on the management of the patients justify the current practice of routine histopathological examination of resected appendix.

Pediatric appendicitis: pathophysiology and appropriate use of diagnostic imaging

Evaluating children for appendicitis can be extremely difficult, and various strategies have been developed to improve the precision of preoperative diagnosis. Among these, ultrasound and computed tomography (CT) are now widely used but remain controversial. Although CT scanning is superior to ultrasound in terms of diagnostic accuracy for appendicitis, the large dose of ionizing radiation from CT and the risk of subsequent radiation-induced malignancy (RIM) are of particular concern in pediatric patients. This article reviews the literature on the pathophysiology, morbidity and mortality of appendicitis, summarizes the data regarding pediatric imaging in appendicitis, provides a practical approach to imaging for clinicians who evaluate pediatric patients, and makes recommendations for reducing the risk of RIM in pediatric patients.

Protocol for suspected pediatric appendicitis limits computed tomography utilization

BACKGROUND

Despite radiation concerns, computed tomography (CT) remains the favored imaging modality at many children's hospitals for appendicitis. We sought to reduce CT utilization for appendicitis in a children's hospital with an algorithm relying on 24-h ultrasound (US) as the primary imaging study.

MATERIALS AND METHODS

An US-based protocol for suspected appendicitis was adopted at the end of the fiscal year (FY) 2011. Data were collected for 12 mo before and 24 mo after implementation. Imaging test usage and charges were adjusted per annual number of appendectomies. Training of emergency department staff continued over 1 y after protocol implementation.

RESULTS

For FY 2011, 644 abdominal CT and 1088 appendix US were ordered, and 249 laparoscopic appendectomies (LAs) were performed. After protocol implementation, FY 2012: 535 CT, 1285 US, and 265 LA were performed; and FY 2013: 330 CT, 1235 US, and 236 LA were performed. Length of stay decreased from before to after protocol (2.57 ± 0.29 versus 2.15 ± 0.11 d), P < 0.001. CTs per appendectomy decreased 42% from FY 2011 to FY 2013 (2.43 versus 1.40, P < 0.001) and 30% from before to after protocol (2.43 versus 1.70, P < 0.001). A corresponding 27% increase in number of US before to after protocol (4.11 versus 5.20 US/appendectomy, P = 0.004) occurred. CT and US charges decreased $2253 and $6633 per appendectomy for FY 2012 and 2013, respectively.

CONCLUSIONS

Protocol-driven workup with US significantly reduced CT utilization, radiation exposure, and imaging-related charges in children with suspected appendicitis. Ongoing training of emergency department staff is required to ensure protocol compliance.

Use and accuracy of diagnostic imaging in the evaluation of pediatric appendicitis

BACKGROUND

There are safety concerns about the use of radiation-based imaging (computed tomography [CT]) to diagnose appendicitis in children. Factors associated with CT use remain to be determined.

METHODS

For patients ≤18 years old undergoing appendectomy, we evaluated diagnostic imaging performed, patient characteristics, hospital type, and imaging/pathology concordance (2008-2012) using data from Washington State's Surgical Care and Outcomes Assessment Program.

RESULTS

Among 2538 children, 99.7% underwent pre-operative imaging. 52.7% had a CT scan as their first study. After adjustment, age >10 years (OR 2.9 (95% CI 2.2-4.0), Hispanic ethnicity (OR 1.7, 95% CI 1.5-1.9), and being obese (OR 1.7, 95% CI 1.4-2.1) were associated with CT use first. Evaluation at a non-children's hospital was associated with higher odds of CT use (OR 7.9, 95% CI 7.5-8.4). Ultrasound concordance with pathology was higher for males (72.3 vs. 66.4%, p=.03), in perforated appendicitis (75.9 vs. 67.5%, p=.009), and at children's hospitals compared to general adult hospitals (77.3 vs. 62.2%, p<.001). CT use has decreased yearly statewide.

CONCLUSIONS

Over 50% of children with appendicitis had radiation-based imaging. Understanding factors associated with CT use should allow for more specific QI interventions to reduce radiation exposure. Site of care remains a significant factor in radiation exposure for children.

Better visualization of vermiform appendix with tissue harmonic imaging compared to conventional sonography

BACKGROUND

Surgery of appendicitis carries 7-11% negative appendectomy rates. Sonographically visualized normal appendix precludes unnecessary computed tomography (CT) examination and may reduce negative appendectomy rates. Tissue harmonic imaging (THI) has been reported to improve the overall image quality.

OBJECTIVE

We aimed to assess whether THI is more successful than conventional ultrasonography (US) in detecting normal and pathologic appendices.

PATIENTS AND METHODS

The study was performed on 185 patients who applied for routine US examinations in whom clinical findings of appendicitis were detected in 25. We searched for the appendix; applying both THI and conventional US to each patient, one before and the other after the routine US examinations. Patients were divided into two groups; one was evaluated first with conventional US and the other first with THI. When the appendix was found, localization, diameter and time spent for visualization were recorded. Twelve patients were operated; all of whom had appendicitis pathologically. Two methods were compared for: 1. Success rates in all patients; female, male and child groups separately; 2. Visualization of pathologic and normal appendices; 3. Time for visualization of appendix; 4. Comparison of success rates in the adult and child population. The relationship between the rate of visualization and body mass index was evaluated.

RESULTS

The appendix was visualized better by THI in all patients, and in the female and male groups (P < 0.001). In children, both methods were more successful compared to adults (P < 0.001, compared to male group, P < 0.001, compared to female group), with no difference between the methods (P = 0.22). When only the normal appendices were concerned, there was significant difference between both methods (P < 0.000). Both methods detected pathologic appendices better than normal ones, with a higher ratio for THI (P = 0.022 for the THI group, and χ(2) = 7.22, P = 0.07 for the conventional US group). THI visualized the appendix faster. Both methods were more successful in lean patients (P = 0.004 for THI, P = 0.001 for conventional US imaging).

CONCLUSIONS

THI visualizes appendix better than conventional US. It is a simple and time saving method that may eliminate further diagnostic imaging, and it may decrease negative appendectomy rates and related complications.

Efficacy of preoperative computed tomography imaging to reduce negative appendectomies in patients undergoing surgery for left lower quadrant abdominal pain

BACKGROUND

Clinical assessment of acute appendicitis can be challenging due to atypical presentation. Computed-tomography can reduce negative appendectomies but not without adverse effects. We report our experience with preoperative CT-scan in patients with suspected acute appendicitis.

PATIENTS AND METHODS

During 3-years, 257 adult patients underwent appendectomy. We retrospectively reviewed clinical information, CT-scans, histological data. Patients were divided in four groups: Group I: low clinical probability without CT-scan; Group II: low clinical probability with CT-scan; Group III: high clinical probability without CT-scan; Group IV: high clinical probability with CT-scan. Negative appendectomies were determined from histological examination. Negative appendectomy rate was compared between groups of the same clinical probability differing on whether a pre-operative CT scan was performed or not (Group I vs II, Group III vs IV).

RESULTS

Groups I,II,III,IV included 12.4%, 18.2%, 54.5% and 14.8% of patients, respectively. The corresponding negative appendectomy rates were 18.7%, 4.3%, 4.2% and 2.6%. Odds ratio of negative appendectomy for patients without CT-scan was 5.2 (95% CI: 1.2-27.7) when there was low clinical probability and 1.6 (95% CI: 0.2-14.2) for high clinical probability.

CONCLUSION

Patients with low clinical probability of acute appendicitis benefit the most from preoperative CT while this does not apply to patients with high clinical probability.

Diagnostic imaging utilization in cases of acute appendicitis: multi-center experience

The purpose of this cross-sectional study was to measure imaging utilization rates and the negative appendectomy rate (NAR) in metropolitan Seoul, Korea. The study included 2321 adolescents and adults (≥ 15 yr; median [interquartile range] age, 37 [27-50] yr; 46.7% female) undergoing appendectomy in 2011 at eight tertiary and three secondary hospitals. Imaging utilization rate was 99.7% (95% confidence interval, 99.4%-99.9%). CT and ultrasonography utilization rates as an initial imaging modality were 93.1% (92.0%-94.1%), and 6.5% (5.6%-7.6%), respectively. The NAR in patients undergoing CT only, complementary ultrasonography following CT, ultrasonography only, and complementary CT following ultrasonography were 3.3% (2.6%-4.1%), 27% (14%-44%), 9% (4%-16%), and 8% (2%-20%), respectively. The use of ultrasonography instead of CT as the initial imaging modality was significantly associated with higher NAR (adjusted odds ratio [AOR], 2.28 [1.22-4.27]; risk difference, 4.4 [0-8.8] percentage points), however, the population attributable risk was 0.3 [0-0.6] percentage points. We observed a very high CT utilization rate and a low NAR in metropolitan Seoul. Although the use of CT was significantly associated with the lower NAR, CT utilization rate already has reached the level that increase in CT utilization from the status quo would hardly decrease the NAR further.

Histopathological findings in appendectomy specimens: a study of 24,697 cases

PURPOSE

Appendicitis is by far the commonest major emergency general surgical operation. Histopathological examination of the appendix is routinely performed.

METHODS

This study is a retrospective analysis of 24,697 appendectomies performed from January 2003 to December 2011. Pathological reports were analyzed for the following parameters: age, gender, and pathological diagnosis.

RESULTS

Appendectomy specimens represent 17 % of all pathological reports. Acute appendicitis was present in 19,637 (79.5 %) patients. The perforation rate was 6.3 % and was significantly higher in adult patients. The negative appendectomy rate was 15 % and was significantly higher in female and adult patients. The incidence of negative appendectomies had clearly decreased over the 9-year period distribution. Incidental unexpected pathological diagnoses were noted in 226 (0.9 %) appendectomy specimens. Neoplastic lesions were present in 171 cases (0.7 %); they include carcinoid, adenocarcinoma, and mucinous neoplasms.

CONCLUSIONS

Routine pathological examination of appendectomy specimens is expensive. With advances in technology and imaging modalities, the diagnosis of acute appendicitis has improved, with a subsequent significant reduction in negative appendectomy. There are still a number of unusual diagnoses found in appendicectomy specimens supporting the continued use of routine histology.

Quantitative measurement of elasticity of the appendix using shear wave elastography in patients with suspected acute appendicitis

INTRODUCTION

Shear wave elastography (SWE) has not been studied for diagnosing appendicitis. We postulated that an inflamed appendix would become stiffer than a normal appendix. We evaluated the elastic modulus values (EMV) by SWE in healthy volunteers, patients without appendicitis, and patients with appendicitis. We also evaluated diagnostic ability of SWE for differentiating an inflamed from a normal appendix in patients with suspected appendicitis.

MATERIALS AND METHODS

Forty-one patients with clinically suspected acute appendicitis and 11 healthy volunteers were prospectively enrolled. Gray-scale ultrasonography (US), SWE and multi-slice computed tomography (CT) were performed. The EMV was measured in the anterior, medial, and posterior appendiceal wall using SWE, and the highest value (kPa) was recorded.

RESULTS

Patients were classified into appendicitis (n = 30) and no appendicitis groups (n = 11). One case of a negative appendectomy was detected. The median EMV was significantly higher in the appendicitis group (25.0 kPa) compared to that in the no appendicitis group (10.4 kPa) or in the healthy controls (8.3 kPa) (p<0.001). Among SWE and other US and CT features, CT was superior to any conventional gray-scale US feature or SWE. Either the CT diameter criterion or combined three CT features predicted true positive in 30 and true negative in 11 cases and yielded 100% sensitivity and 100% specificity. An EMV of 12.5 kPa for the stiffest region of the appendix predicted true positive in 28, true negative in 11, and false negative in two cases. The EMV (≥12.5 kPa) yielded 93% sensitivity and 100% specificity.

CONCLUSION

Our results suggest that EMV by SWE helps distinguish an inflamed from a normal appendix. Given that SWE has high specificity, quantitative measurement of the elasticity of the appendix may provide complementary information, in addition to morphologic features on gray-scale US, in the diagnosis of appendicitis.

Comparison of appendicectomy outcomes: acute surgical versus traditional pathway

INTRODUCTION

The acute surgical unit (ASU) is an evolving novel concept introduced to address the challenge of maintaining key performance indicators (KPIs) in the face of an increasing acute workload.

METHODS

The aim of this retrospective study was to compare the performance of the ASU (from June 2008 to December 2010) at Auckland City Hospital with the traditional model (from January 2006 to May 2008) and benchmark the results against other similar published studies. The analysis was on the basis of KPIs for 1857 appendicectomies, which form a large volume of acute surgical presentations.

RESULTS

Our results show significant improvement in length of stay (2.8 days, 2.6 days, P = 0.0001) and proportion of daytime operations (59.4%, 65.8%, P = 0.004), in keeping with other studies on benchmarking.

CONCLUSION

The introduction of ASU has led to significant improvements in some KPIs for appendicectomy outcomes in the face of an increasing workload.

Long-term outcomes of patients with nonsurgically managed uncomplicated appendicitis

BACKGROUND

Emerging literature has supported the safety of nonoperative management of uncomplicated appendicitis.

STUDY DESIGN

Patients with emergent, uncomplicated appendicitis were identified by appropriate ICD-9 diagnosis codes in the California Office of Statewide Health Planning and Development database from 1997 to 2008. Rates of treatment failure, recurrence, and perforation after nonsurgical management were calculated. Factors associated with treatment failure, recurrence, and perforation were identified using multivariable logistic regression. Mortality, length of stay, and total charges were compared between treatment cohorts using matched propensity score analysis.

RESULTS

Of 231,678 patients with uncomplicated appendicitis, the majority (98.5%) were managed operatively. Of the 3,236 nonsurgically managed patients who survived to discharge without an interval appendectomy, 5.9% and 4.4% experienced treatment failure or recurrence, respectively, during a median follow-up of more than 7 years. There were no mortalities associated with treatment failure or recurrence. The risk of perforation after discharge was approximately 3%. Using multivariable analysis, race and age were significantly associated with the odds of treatment failure. Sex, age, and hospital teaching status were significantly associated with the odds of recurrence. Age and hospital teaching status were significantly associated with the odds of perforation. Matched propensity score analysis indicated that after risk adjustment, mortality rates (0.1% vs 0.3%; p = 0.65) and total charges ($23,243 vs $24,793; p = 0.70) were not statistically different between operative and nonoperative patients; however, length of stay was significantly longer in the nonoperative treatment group (2.1 days vs 3.2 days; p < 0.001).

CONCLUSIONS

This study suggests that nonoperative management of uncomplicated appendicitis can be safe and prompts additional investigations. Comparative effectiveness research using prospective randomized studies can be particularly useful.

Ultrasonography/MRI versus CT for diagnosing appendicitis

BACKGROUND

Cross-sectional imaging increases accuracy in diagnosing appendicitis. We hypothesized that a radiation-free imaging pathway of ultrasonography selectively followed by MRI would not change clinical end points compared with computed tomography (CT) for diagnosis of acute appendicitis in children.

METHODS

We retrospectively reviewed children (<18 years old) who had diagnostic imaging for suspected acute appendicitis between November 2008 and October 2012. Before November 2010 CT was used as the primary imaging modality (group A); subsequently, ultrasonography was the primary imaging modality followed by MRI for equivocal findings (group B). Data collected included time from triage to imaging and treatment and results of imaging and pathology.

RESULTS

Six hundred sixty-two patients had imaging for suspected appendicitis (group A = 265; group B = 397, of which 136 [51%] and 161 [41%], respectively, had positive imaging for appendicitis). Negative appendectomy rate was 2.5% for group A and 1.4% for group B. Perforation rate was similar for both groups. Time from triage to antibiotic administration and operation did not differ between groups A and B. There was higher proportion of positive imaging and appendectomies in group A and thus more negative imaging tests in group B (ultrasonography and MRI), but diagnostic accuracy of the 2 imaging pathways was similar.

CONCLUSIONS

In children with suspected acute appendicitis, a radiation-free diagnostic imaging of ultrasonography selectively followed by MRI is feasible and comparable to CT, with no difference in time to antibiotic administration, time to appendectomy, negative appendectomy rate, perforation rate, or length of stay.

Do clinical outcomes suffer during transition to an ultrasound-first paradigm for the evaluation of acute appendicitis in children?

OBJECTIVE

The objective of our study was to examine whether the rate of complicated appendicitis and the hospital length of stay (LOS) increased during the transition to an ultrasound-first paradigm for the imaging evaluation of acute appendicitis.

MATERIALS AND METHODS

All pediatric patients with surgically proven appendicitis from 2005 to 2011 were identified by searching the hospital billing database for the discharge diagnosis codes for simple appendicitis (ICD-9 [International Classification of Diseases, 9th revision] code 540.9) and complicated appendicitis (ICD-9 codes 540.0 and 540.1). Annual trends of the proportions of these patients who underwent ultrasound and CT were determined and plotted for the study period. Correlation of complicated appendicitis and median hospital LOS with calendar year was assessed using the Spearman (ρ) rank correlation test. RESULTS. Eight hundred four patients met the inclusion criteria. The percentage of patients who underwent CT only showed a moderate downward association with year (ρ = -0.32, p < 0.01), and the percentage of patients who underwent ultrasound first showed a moderate upward trend (ρ = 0.44, p < 0.01). The percentage of patients with ultrasound as the only study performed before appendectomy increased moderately over the 7-year study period (ρ = 0.33, p < 0.01). The percentage of patients with complicated appendicitis and the median hospital LOS did not increase significantly over the study duration (ρ = -0.01, p = 0.74 and ρ = -0.04, p = 0.25, respectively).

CONCLUSION

The transition to an ultrasound-first pathway for the imaging workup of acute appendicitis in children occurred without evidence of a corresponding increase in the proportion of patients with complicated appendicitis or in the median hospital LOS.

LOCAT (low-dose computed tomography for appendicitis trial) comparing clinical outcomes following low- vs standard-dose computed tomography as the first-line imaging test in adolescents and young adults with suspected acute appendicitis: study protocol for a randomized controlled trial

BACKGROUND

Computed tomography is widely used to diagnose acute appendicitis. Many adolescents and young adults are exposed to the associated radiation. A recent single-institution trial has reported promising results for low-dose computed tomography; however, this technique has not yet been widely adopted. LOCAT (low-dose computed tomography for appendicitis trial), a multi-institution randomized controlled non-inferiority trial, aims to compare low-dose computed tomography and standard-dose computed tomography as the first-line imaging tests for adolescents and young adults, and therefore to test the generalizability of the previous single-institution trial results.

METHODS/DESIGN

Participants with suspected appendicitis are randomly assigned to either the low-dose group (with a typical effective dose of 2 mSv) or the standard-dose group (as used in normal practice at each participating site, typically 8 mSv). The primary end point is the negative appendectomy rate (the percentage of the number of uninflamed appendices that were removed among all non-incidental appendectomies), which is a consequence of false-positive diagnoses, with a non-inferiority margin of 4.5 percentage points. The key secondary end point is the appendiceal perforation rate, which is a consequence of delayed (or false-negative) diagnoses. Participant recruitment will be continued until the number of non-incidental appendectomies for each group exceeds 444. The total number of expected participants approximates 3,000, including those not undergoing appendectomy.

DISCUSSION

In addition to the study protocol, we elaborate on several challenging or potentially debatable components of the study design, including the broad eligibility criteria, choice of the primary end point, potential effect of using advanced imaging techniques on study results, determining and adjusting the radiation doses, ambiguities in reference standards, rationale for the non-inferiority margin, use of the intention-to-treat approach and difficulties in defining adverse events.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01925014.