Institutional review of patients presenting with suspected appendicitis

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

IMPLICATIONS FOR PRACTICE

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

Cohort study of 1241 patients to identify predictors of negative appendicectomy

BACKGROUND

Acute Appendicitis is the most common surgical presentation within Australia. Despite the increasing use of radiological investigations to aid clinical diagnosis, many appendectomies result in a histologically normal appendix. This study examines the histological negative appendicectomy rate (NAR) in a metropolitan hospital and determine factors associated with a negative appendicectomy (NA).

METHODS

Patients who underwent emergency appendicectomy for suspected acute appendicitis at Logan Hospital, Australia, between February 2016 and March 2019 inclusive were included. Clinicopathologic and imaging variables were analysed for associations with NA.

RESULTS

A total of 1241 patients underwent emergency appendicectomy of which 121 patients (9.8%) had a NA. The NAR for clinical diagnosis alone (no imaging) was 9.9%, 14.5% for ultrasonography alone and computed tomography scan alone was 4.9%. Univariate analysis revealed age <27 years (P < 0.001), absence of hypertension (P = 0.008), symptoms >48 hours (P < 0.001), absence of leucocytosis (P < 0.001), undergoing ultrasonography only (P < 0.001), undergoing computed tomography scan only (P < 0.001), macroscopically normal appendix (P < 0.001) and time to operation >24 hours (P < 0.001) were associated with NA. Multivariate analysis identified symptoms >48 h at presentation (odds ratio (OR) 1.98, 95% confidence interval (CI) 1.20-3.24; P = 0.007), absence of leucocytosis (OR 2.41, 95% CI 1.52-3.81; P < 0.001) and macroscopically normal appendix (OR 5.70, 95% CI 3.49-9.33; P < 0.001) to be associated with a NA.

CONCLUSION

The NAR reported is lowest in an Australian institution. The identified predictors of NA will be useful in identifying patients who would truly benefit from an appendicectomy versus those would have a higher rate of NA who may be suitable to be treated non-operatively to be spared the unnecessary morbidity of surgery.

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

PURPOSE

To identify available clinical prediction rules (CPRs) and investigate their ability to rule out appendicitis in children presenting with abdominal pain at the emergency department, and accordingly select CPRs that could be useful in a future prospective cohort study.

METHODS

A literature search was conducted to identify available CPRs. These were subsequently tested in a historical cohort from a general teaching hospital, comprising all children (< 18 years) that visited the emergency department between 2012 and 2015 with abdominal pain. Data were extracted from the electronic patient files and scores of the identified CPRs were calculated for each patient. The negative likelihood ratios were only calculated for those CPRs that could be calculated for at least 50% of patients.

RESULTS

Twelve CPRs were tested in a cohort of 291 patients, of whom 87 (29.9%) suffered from acute appendicitis. The Ohmann score, Alvarado score, modified Alvarado score, Pediatric Appendicitis score, Low-Risk Appendicitis Rule Refinement, Christian score, and Low Risk Appendicitis Rule had a negative likelihood ratio < 0.1. The Modified Alvarado Scoring System and Lintula score had a negative likelihood ratio > 0.1. Three CPRs were excluded because the score could not be calculated for at least 50% of patients.

CONCLUSION

This study identified seven CPRs that could be used in a prospective cohort study to compare their ability to rule out appendicitis in children and investigate if clinical monitoring and re-evaluation instead of performing additional investigations (i.e., ultrasound) is a safe treatment strategy in case there is low suspicion of appendicitis.

Evaluation of the Potential Association of Platelet Levels, Mean Platelet Volume and Platelet Distribution Width with Acute Appendicitis

BACKGROUND:

The occurrence and early management of acute appendicitis among children are especially important due to the difficult diagnosis and nonspecific symptoms of the disease. Diagnosis of appendicitis in children is very difficult due to similarity of its symptoms to other diseases, and also its self-limiting nature Platelet indexes such as mean platelet volume (MPV) and platelet distribution width (PDW) have been suggested as a biomarker of inflammation.

AIM:

Therefore, we examined the association of MPV and PDW with acute appendicitis in children.

METHODS:

This cross-sectional study was conducted on 464 patients with suspected acute appendicitis under the age of 18 years referred to the specialised hospitals of the ten studied provinces between October 2014 and October 2015. All data obtained regarding patient’s lab tests, i.e. platelet count, MPV and PDW and also radiological studies and surgical reports were gathered in datasheets and analysed to evaluate the potential association of platelet levels, mean platelet volume (MPV) and platelet distribution width (PDW) with acute appendicitis

RESULTS:

Our results showed that the MPV was significantly higher in acute appendicitis in comparison to perforated appendicitis as well as acute gangrenous appendicitis. PDW was significantly higher in acute appendicitis in comparison to perforated appendicitis and acute gangrenous appendicitis. The current project indicated that PDW < 10.05 had a sensitivity of 35% and specificity of 75%, platelet count < 229500 had a sensitivity of 24% and specificity of 75% and MPV < 8.95 had a sensitivity of 70% and specificity of 71%.

CONCLUSION:

Our study suggested that platelet indexes such as MPV and PDW could significantly correlate with acute appendicitis in pediatric patients. Hence, we believe that both MPV and PDW could use as a simple and low-cost lab test for diagnosing acute appendicitis. Also, this study revealed that the MPV lower than 8.95 could be a novel index for diagnosing acute appendicitis with sensitivity of 70% and specificity of 71%.

Emergency appendicectomy in Australia: findings from a multicentre, prospective study

BACKGROUND

Emergency appendicectomy is the most common emergency surgical procedure performed in Australia. Despite this frequency, there is a relative paucity of contemporary, broad-based, local data that examine how emergency appendicectomies are currently performed and what are the outcomes from these operations.

METHODS

A multicentre, prospective, observational study was performed. Patients were recruited by local investigators for a period of 2 months with 30-day follow-up. Patients were eligible for study inclusion if they underwent an emergency appendicectomy for suspected acute appendicitis. The primary outcome of the study was the negative appendicectomy rate (NAR), with secondary outcomes including 30-day complication rates, method of operation and conversion rates.

RESULTS

A total of 1189 patients were recruited across 27 centres. The NAR across all centres was 19.0%. 98.2% of appendicectomies were performed with a laparoscopic-first approach. The rate of conversion from laparoscopy to open operation was 2.4%. 9.4% of patients were recorded as having one or more of the following complications: readmission (6.6%), surgical site infection (1.9%), intra-abdominal abscess (2.7%) or further intervention (1.5%). Patients who had an open operation had higher rates of readmission and surgical site infection.

CONCLUSION

The NAR found in this study is within the traditional measures of acceptance; however, this rate is high when measured against modern international benchmarks.

WSES Jerusalem guidelines for diagnosis and treatment of acute appendicitis

Acute appendicitis (AA) is among the most common cause of acute abdominal pain. Diagnosis of AA is challenging; a variable combination of clinical signs and symptoms has been used together with laboratory findings in several scoring systems proposed for suggesting the probability of AA and the possible subsequent management pathway. The role of imaging in the diagnosis of AA is still debated, with variable use of US, CT and MRI in different settings worldwide. Up to date, comprehensive clinical guidelines for diagnosis and management of AA have never been issued. In July 2015, during the 3rd World Congress of the WSES, held in Jerusalem (Israel), a panel of experts including an Organizational Committee and Scientific Committee and Scientific Secretariat, participated to a Consensus Conference where eight panelists presented a number of statements developed for each of the eight main questions about diagnosis and management of AA. The statements were then voted, eventually modified and finally approved by the participants to The Consensus Conference and lately by the board of co-authors. The current paper is reporting the definitive Guidelines Statements on each of the following topics: 1) Diagnostic efficiency of clinical scoring systems, 2) Role of Imaging, 3) Non-operative treatment for uncomplicated appendicitis, 4) Timing of appendectomy and in-hospital delay, 5) Surgical treatment 6) Scoring systems for intra-operative grading of appendicitis and their clinical usefulness 7) Non-surgical treatment for complicated appendicitis: abscess or phlegmon 8) Pre-operative and post-operative antibiotics.

Prospective evaluation of the Sunshine Appendicitis Grading System score

BACKGROUND

Although there is a wealth of information predicting risk of post-operative intra-abdominal collection and guiding antibiotic therapy following appendicectomy, confusion remains because of lack of consensus on the clinical severity and definition of 'complicated' appendicitis. This study aimed to develop a standardized intra-operative grading system: Sunshine Appendicitis Grading System (SAGS) for acute appendicitis that correlates independently with the risk of intra-abdominal collections.

METHODS

Two-hundred and forty-six patients undergoing emergency laparoscopy for suspected appendicitis were prospectively scored according to the severity of appendicitis and followed up for complications including intra-abdominal collection. After termination of the study, the SAGS score was repeated by an independent surgeon based on operation notes and intra-operative photography to determine inter-rater agreement. The primary outcome measure was incidence of intra-abdominal collection, secondary outcome measures were all complications and length of stay.

RESULTS

SAGS score demonstrated good inter-rater agreement (kappa K_w 0.869; 95% CI 0.796-0.941; P < 0.001). A risk ratio of 2.594 (95% CI 0.655-4.065; P < 0.001) for intra-abdominal collection was found using SAGS score as a predictor. The discriminative ability of SAGS score was supported by an area under the curve value of 0.850 (95% CI 0.799-0.892; P < 0.001).

CONCLUSIONS

SAGS score can be used to simply and accurately classify the severity of appendicitis and to independently predict the risk of intra-abdominal collection. It can therefore be used to stratify risk, guide antibiotic therapy, follow-up and standardize the definitions of appendicitis severity for future research.