Role of Preoperative Antibiotic Treatment While Awaiting Appendectomy: The PERFECT-Antibiotics Randomized Clinical Trial

Importance

Antibiotics are thought to decelerate inflammation progression and reduce complications in acute uncomplicated appendicitis. The evidence of their effectiveness is insufficient, and treatment practices vary widely.

Objective

To investigate the effect of preoperatively started antibiotic treatment on the rate of appendiceal perforation.

Design, Setting, and Participants

This multicenter, noninferiority, open-label randomized clinical trial was conducted in 2 hospitals in Finland and 1 hospital in Norway between May 18, 2020, and January 22, 2023. Data analysis was performed from March 2023 to March 2024. Eligible patients were adults (aged >18 years) diagnosed with presumed uncomplicated acute appendicitis. Patients with allergies or other contraindications to study antibiotics, previously started antibiotic treatment, pregnancy, a suspicion of perforated appendicitis, or other reasons to perform prompt surgery were excluded. Patients were randomized 1:1 with a web-based service simultaneously as the laparoscopic appendectomy was scheduled.

Interventions

Antibiotic treatment started while waiting for surgery (cefuroxime, 1500 mg, and metronidazole, 500 mg, every 8 hours until the surgery) or waiting without antibiotic treatment. Patients in both groups received a single prophylactic dose of antibiotics in the induction of anesthesia.

Main Outcomes and Measures

The primary outcome was perforated appendicitis diagnosed during surgery. The absolute difference in perforation rates was compared between the groups by an intention-to-treat analysis, and the predefined noninferiority margin was 5 percentage points. Secondary outcomes included surgical site infections within 30 days.

Results

A total of 1797 patients were randomly assigned to either the antibiotic group (n = 901) or no-antibiotic group (n = 896). Median (IQR) patient age was 35 (28-46) years, and 793 patients (45%) were female. After randomization, 23 patients (1.3%) were excluded, leaving 1774 patients for the intention-to-treat analyses. The difference between the appendiceal perforation rates met the noninferiority threshold: 74 of 888 patients in the antibiotic group (8.3%) vs 79 of 886 patients in the no-antibiotic group (8.9%; absolute difference, 0.6 percentage points; 95% CI, -2.0 to 3.2 percentage points; P = .66; risk ratio, 1.07; 95% CI, 0.79 to 1.45). For secondary outcome, the surgical site infection rate was slightly lower in the antibiotic group (14 of 887 [1.6%]) vs the no-antibiotic group (28 of 886 [3.2%]; absolute difference, 1.6 percentage points; 95% CI, 0.2 to 3.0 percentage points; P = .03).

Conclusions and Relevance

In this multicenter noninferiority randomized clinical trial, preoperatively started antibiotic treatment did not decrease the risk of appendiceal perforation when appendectomy was performed within 24 hours in adult patients with presumed uncomplicated acute appendicitis.

Trial Registration

EudraCT Identifier: 2019-002348-26.

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.

A randomized double-blind noninferiority clinical multicenter trial on oral moxifloxacin versus placebo in the outpatient treatment of uncomplicated acute appendicitis: APPAC IV study protocol

BACKGROUND

Antibiotic therapy is currently considered a safe and effective treatment alternative for computed tomography (CT)-confirmed uncomplicated acute appendicitis with recent studies reporting good results on both oral antibiotics only and outpatient management. Furthermore, there are promising pilot results on uncomplicated acute appendicitis management with symptomatic treatment (placebo). This trial aims to assess whether both antibiotics and hospitalization can be safely omitted from the treatment of uncomplicated acute appendicitis.

METHODS

The APPAC IV (APPendicitis Acuta IV) trial is a randomized, double-blind, multicenter noninferiority clinical trial comparing oral moxifloxacin with oral placebo in an outpatient setting with a discharge directly from the emergency room (ER). Adult patients (18-60 years) with CT-confirmed uncomplicated acute appendicitis (absence of appendicolith, abscess, perforation, tumor, appendiceal diameter ⩾15 mm on CT, or body temperature >38 °C) will be enrolled in nine Finnish hospitals. Primary outcome is treatment success at 30 days, that is, the resolution of acute appendicitis resulting in discharge from the hospital without appendectomy during the 30-day follow-up evaluated using a noninferiority design with a noninferiority margin of 6 percentage points. Noninferiority will be evaluated using one-sided 95% confidence interval of proportion difference between groups. Secondary endpoints include postintervention complications, recurrent appendicitis after the 30-day follow-up, duration of hospital stay, admission to hospital and reason for admission, readmissions to emergency department or hospitalization, VAS pain scores, quality of life, sick leave, and treatment costs. The follow-up after discharge from the ER includes a phone call at day 1, and at 3-4 days, 30 days, and 1, 3, 5, 10, and 20 years. Those eligible patients, who decline to undergo randomization, will be invited to participate in a concurrent observational cohort study with follow-up at 30 days, and 1 and 5 years.

DISCUSSION

To our knowledge, APPAC IV trial is the first large randomized, double-blind, noninferiority multicenter clinical trial aiming to compare oral antibiotics and placebo for CT-diagnosed uncomplicated acute appendicitis in an outpatient setting. The study aims to bridge the major knowledge gap on whether antibiotics and hospitalization or both can be omitted in the treatment of uncomplicated acute appendicitis.

TRIAL REGISTRATION

The study protocol has been approved by the Clinical Trials Information System (CTIS) of the European Medicines Agency (EMA), study number: 2023-506213-21-00 and the trial has been registered in ClinicalTrials.gov, NCT06210269.

Antibiotic treatment versus appendicectomy for acute appendicitis in adults: an individual patient data meta-analysis

BACKGROUND

Randomised controlled trials (RCTs) have found antibiotics to be a feasible and safe alternative to appendicectomy in adults with imaging-confirmed acute appendicitis. However, patient inclusion criteria and outcome definitions vary greatly between RCTs. We aimed to compare antibiotics with appendicectomy for the treatment of acute appendicitis using individual patient data and uniform outcome definitions.

METHODS

In this individual patient data meta-analysis, we searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials without language restrictions between database inception and June 6, 2023, for RCTs comparing appendicectomy with antibiotics for the treatment of adults (≥18 years) with imaging-confirmed acute appendicitis. Studies without 1-year follow-up data on complications were excluded, as were patients. Corresponding authors of eligible studies were contacted and invited to share data; individual patient data were merged after validation. One-stage meta-analyses were conducted using a generalised, mixed-effects linear regression model, accounting for clustering of patients within studies. The primary outcome was the complication rate at 1-year follow-up, uniformly harmonised across trials using the Clavien-Dindo classification. Complications were further divided into minor (grade 1-2 or equivalent) and major (grade 3-5 or equivalent) complications. Appendicectomy rate during 1 year was a key secondary outcome but not considered a complication for the antibiotics group. Outcomes were described separately for patients with and without an appendicolith. This study is registered with PROSPERO, CRD42023391676.

FINDINGS

Of 887 potentially relevant articles, eight were eligible for inclusion, of which six RCTs could provide data for 2101 eligible patients (1050 assigned to antibiotics and 1051 assigned to appendicectomy; 830 [39·5%] women and 1271 [60·5%] men). All studies raised some bias concerns due to absence of blinding. One study was judged to have a high risk of bias due to the exclusion of eligible patients after randomisation, but these patients were eligible for inclusion in our meta-analysis. At 1 year, 57 (5·4%) of 1050 patients randomly assigned to antibiotics had a complication compared with 87 (8·3%) of 1051 patients randomly assigned to appendicectomy (odds ratio [OR] 0·49 [95% CI 0·20 to 1·20]; risk difference -4·5 percentage points [95% CI -11·6 to 2·6]). At 1 year, 1025 (97·5%) patients in the appendicectomy group had undergone appendicectomy compared with 356 (33·9%) patients in the antibiotics group. In patients with an appendicolith at pre-interventional imaging, there were more complications at 1 year among patients who received antibiotic treatment than among those who underwent appendicectomy (29 [15·0%] of 193 patients vs 12 [6·3%] of 190 patients; OR 2·82 [95% CI 1·11 to 7·18]; risk difference 13·2 percentage points [95% CI 2·3 to 24·2]). In the antibiotics group, 94 (48·7%) of 193 patients with an appendicolith underwent appendicectomy within 1 year versus 262 (30·6%) of 857 patients without an appendicolith.

INTERPRETATION

This meta-analysis showed that antibiotic treatment in adults with imaging-confirmed acute appendicitis was a safe alternative to surgery and resulted in around two-thirds of patients avoiding appendicectomy during the first year. In patients with an appendicolith, initial antibiotic treatment increased the risk of complications compared with appendicectomy, and around half of these patients assigned to antibiotics underwent step-up appendicectomy within 1 year. These data should be key components in shared decision making.

FUNDING

None.

Diagnostic value of the appendicitis inflammatory response (AIR) score. A systematic review and meta-analysis

BACKGROUND

Clinical scoring algorithms are cost efficient in patients with suspicion of acute appendicitis. This is a systematic review and meta-analysis of the diagnostic properties of the Appendicitis Inflammatory Response (AIR) score compared with the Alvarado score.

METHODS

The PubMed, EMBASE, Web of Science and Google Scholar databases were searched for reports on the diagnostic properties of the AIR score from 2008 to July 18, 2024. A meta-analysis of the receiver operating characteristic (ROC) area and the sensitivity and specificity for all and advanced appendicitis patients was performed. Advanced appendicitis was defined as perforated or gangrenous appendicitis or appendicitis abscess or phlegmon or if described as complicated appendicitis. The risk of bias was estimated via the QUADAS-2 tool. The ROC areas of the AIR score and the Alvarado score were compared.

RESULTS

A total of 26 reports with a total of 15.699 patients were included. The area under the ROC curve for the AIR score was 0.86 (95% CI 0.83-0.88) for all patients with appendicitis and 0.93 (CI 0.91-0.96) for those with advanced appendicitis, which was greater than the corresponding areas for the Alvarado score (0.79, CI 0.76; 0.81) and 0.88, CI 0.82; 0.95), respectively. At > 4 points, the sensitivity was 0.91 (CI 0.88; 0.94) for all patients with appendicitis and 0.95 (CI 0.94; 0.97) for those with advanced appendicitis. At > 3 points, the sensitivity was 0.95 (0.90; 0.97) for all patients with appendicitis and 0.99 (0.97; 0.99) for those with advanced appendicitis. At > 8 points, the specificity was 0.98 (0.97; 0.99) for all patients with appendicitis and 0.99 (0.97; 0.99) for those with advanced appendicitis. The included studies had a low risk for bias and low heterogeneity.

CONCLUSION

The AIR score has a better diagnostic capacity than the Alvarado score does. The AIR score is a safe and efficient basis for risk-stratified management of patients suspected of having appendicitis.

Acute appendicitis and its treatment: a historical overview

PURPOSE

Acute appendicitis (AA) is the leading cause of acute abdomen worldwide, with an incidence of 90-100 cases per 100,000 individuals annually and a lifetime risk of 7-12%. Despite its prevalence, historical accounts of AA are limited, particularly when compared to conditions like haemorrhoids, likely due to the appendix's internal location. This article traces the historical evolution of AA treatment from ancient times to the present, highlighting key contributions.

METHODS

A review of common research databases and relevant literature on AA was conducted.

RESULTS

Evidence from ancient Egypt suggests early recognition of the appendix, referring to it as the "worm of the bowel." However, detailed anatomical descriptions and treatment approaches for AA did not emerge until the Renaissance, particularly with contributions from Leonardo da Vinci and Berengario da Carpi. The article traces the progression of AA management, including the first autopsies and surgeries, the development of surgical techniques predating anaesthesia and antisepsis, and advancements achieved from the nineteenth to the twenty-first century. The shift from conservative to surgical approaches is discussed, alongside innovations such as laparoscopic appendicectomy, single-incision laparoscopic surgery (SILS), natural orifice transluminal endoscopic surgery (NOTES), and endoscopic retrograde appendicitis therapy (ERAT). The impact of the COVID-19 pandemic on AA treatment, including adaptations in medical practices, is also explored.

CONCLUSIONS

This review highlights the significant historical developments in AA treatment and its pivotal role in advancing abdominal surgery.

The benefits of interval appendectomy and risk factors for nonoperative management failure in the therapeutic strategy for complicated appendicitis

PURPOSE

Emergency surgery (ES) for complicated appendicitis (CA) is associated with high morbidity. Interval appendectomy (IA) decreases this rate; however, nonoperative management (NOM) is not always successful. Some patients require unplanned ES due to NOM failure (IA failure: IA-F). This study aimed to verify the benefits of IA and to evaluate the risk factors for NOM failure.

METHODS

Patients diagnosed with CA who underwent surgery between January 2012 and December 2021 were included in this study. We compared the surgical outcomes of the ES group with those of the IA success (IA-S) and IA-F groups. We also analyzed 14 factors that predicted NOM failure.

RESULTS

Among 302 patients, the rate of severe complications (Clavien-Dindo grade ≥ III) was significantly higher in the ES group (N = 165) than in the IA-S group (N = 102). The rates were equal between the ES (N = 165) and IA-F (N = 35) groups. NOM was successful in 110 patients and failed in 27. Lack of abscesses, comorbidities, high WBC count, and free air were independent risk factors for NOM failure.

CONCLUSIONS

Considering the benefits of IA and the non-inferior surgical outcomes of IA-F compared to ES, IA is a good therapeutic strategy for CA. However, in patients exhibiting four independent risk factors for NOM failure, careful monitoring of unplanned ES is necessary.

Appendicolith classification: physical and chemical properties of appendicoliths in patients with CT diagnosed acute appendicitis - a prospective cohort study

OBJECTIVE

Appendicoliths are associated with a more complicated course of acute appendicitis and failure of non-operative treatment. We aimed to update the appendicolith classification originally described in 1966 and to assess the association of appendicolith characteristics with appendicitis severity.

DESIGN

This prospective predefined MAPPAC-trial (ClinicalTrials.gov NCT03257423) substudy included patients with CT diagnosed appendicitis presenting with an appendicolith. CT visible appendicoliths were harvested at surgery, measured and characterised by morphological examination complemented with micro-CT and micro-X-ray fluorescence spectroscopy. Patients were categorised into two groups: appendicolith appendicitis without other complications and appendicolith appendicitis with complications (appendiceal gangrene, perforation and/or abscess). The association of appendicolith classification and characteristics with appendicitis severity was evaluated.

RESULTS

Of 78 patients with a CT appendicolith, 41 appendicoliths were collected and classified based on the degree of hardness into three classes. The hardest appendicoliths (class 3) were less common (19.5%) presenting with a stone-hard outer layer and concentrically layered inner structure around a core. The layered inner structure was also observed in class 2 appendicoliths, but was absent in soft, class 1 appendicoliths. Appendicolith hardness or measures (maximum length, diameter and weight) were not associated with appendicitis severity. The spatial distribution of the main inorganic elements of calcium and phosphorus varied within most appendicoliths.

CONCLUSION

This updated classification confirms categorisation of CT visible appendicoliths into three classes based on their physical and chemical characteristics. The data on clinical and aetiopathological characteristics of appendicoliths is scarce and using this systematic classification would add to this understanding.

Is non-operative treatment of acute appendicitis possible: A narrative review

Introduction

Acute appendicitis (AA) represents the most frequent surgical emergency. Perforation was long considered the ultimate outcome of AA, prompting appendectomy; which remains the standard treatment. New data have clarified the role of the appendix, justifying conservative treatment. This narrative review aims to summarize the evidence regarding the non-operative treatment (NOT) of AA in adults.

Methods

The literature search was performed via the PubMed Medline database. Our criteria-based selection resulted in a total of 48 articles for review.

Results

Recent trials and meta-analyses have assessed NOT, which support primary antibiotic treatment of uncomplicated AA. Although it has a significant recurrence and failure rate, NOT does not appear to increase the risk of appendicular perforation. Moreover, NOT compared with appendectomy, seems to be associated with less morbidity, lower cost of care and preserved quality of life.

Conclusion

First-line NOT seems to be a reasonable approach for the treatment of uncomplicated CT-confirmed AA. Careful patient screening would definitely enhance the success rate.

Diagnostic accuracy of doctors at the emergency department and radiologists in differentiating between complicated and uncomplicated acute appendicitis

PURPOSE

To determine the accuracy of final judgements of doctors at the emergency department (ED) and radiologists to differentiate between complicated and uncomplicated acute appendicitis, because these have different treatment options.

METHODS

This prospective, multicenter study included adult patients with imaging-confirmed acute appendicitis, operated with intention to appendectomy. Both doctors at ED and radiologists assessed appendicitis severity as a final judgement of "uncomplicated" or "complicated" appendicitis. Doctors at ED integrated clinical, laboratory, and imaging findings. Radiologists relied solely on imaging findings. Outcomes were accuracy of these judgements for diagnosis of complicated appendicitis compared to the reference standard by an adjudication committee.

RESULTS

After imaging, 1070 patients with confirmed acute appendicitis were included. Doctors at ED accurately labelled 656 of 701 (93.6%) patients with true uncomplicated appendicitis as uncomplicated, and 163 of 369 (44.2%) patients with true complicated appendicitis were labelled as complicated. Sensitivity, specificity, and positive and negative predictive values (PPV and NPV) for complicated appendicitis were 44.2%, 93.6%, and 78.4% and 76.1%, respectively. Comparable accuracy was found for the radiologist's assessment in 941 patients, with true positive rates of 92.2% (581 of 630 patients) for uncomplicated appendicitis and 46.6% (145 of 311 patients) for complicated appendicitis.

CONCLUSION

More than half of all patients with true complicated appendicitis is incorrectly classified as uncomplicated appendicitis according to the judgements of doctors at ED, integrating clinical, laboratory, and imaging results, and of radiologists assessing diagnostic imaging. These judgements are thereby not sufficiently reliable in ruling out complicated appendicitis.

Is there a link between appendicitis and the risk of diverticular disease?: a large German cohort study

PURPOSE

Appendicitis, characterized by inflammation of the vermiform appendix, is a common abdominal emergency necessitating appendectomy. Recent evidence suggests a potential link between appendicitis and subsequent diverticular disease, yet population-based studies investigating this association are limited.

METHODS

Utilizing the Disease Analyzer database encompassing data from over 1000 primary care practices in Germany, we conducted a retrospective cohort study. We included 25,379 adults diagnosed with appendicitis and an equal number of matched controls without appendicitis. The incidence of diverticular disease over a 10-year follow-up period was compared between the two cohorts. Cox regression analysis was performed to assess the association between appendicitis and diverticular disease, adjusting for potential confounders.

RESULTS

Our findings revealed a significant association between appendicitis and subsequent diverticular disease (HR: 1.76; 95% CI: 1.57-1.97), with an increased risk observed across all age groups. Notably, this association was stronger in men (HR: 2.00; 95% CI: 1.68-2.37) than in women (HR: 1.58; 95% CI: 1.36-1.84). The cumulative 10-year incidence of diverticular disease was higher in patients with appendicitis (6.5%) compared to those without (3.6%). Additionally, we observed a clear age-dependent increase in the incidence of diverticular disease.

CONCLUSION

This large-scale population-based study provides valuable insights into the interaction between appendicitis and diverticular disease. The study underscores the need for further research elucidating the underlying mechanisms linking appendicitis to diverticular disease. Probiotics emerge as a potential therapeutic avenue warranting exploration in the management of both conditions. These findings have important implications for clinical practice, highlighting the importance of considering appendicitis as a potential risk factor for diverticular disease, particularly in men. Further investigation is warranted to validate these findings and explore potential therapeutic interventions targeting the shared pathophysiological pathways underlying both conditions.

Acute appendicitis: A block-randomized study on active observation with or without antibiotic treatment

BACKGROUND

Antibiotic treatment of unselected patients with acute appendicitis is safe and effective. However, it is unknown to what extent early provision of antibiotic treatment may represent overtreatment due to spontaneous healing of appendix inflammation. The aim of the present study was to evaluate the role of antibiotic treatment versus active in-hospital observation on spontaneous regression of acute appendicitis.

METHOD

Patients who sought acute medical care at Sahlgrenska University Hospital were block-randomized according to age (18-60 years) and systemic inflammation (C-reactive protein <60 mg/L, white blood cell <13,000/μL), in combination with clinical and abdominal characteristics of acute appendicitis. Study patients received antibiotic treatment and active observation, while control patients were allocated to classic active "wait and see observation" for either disease regression or the need for surgical exploration. According to our standard surgical care, certified surgeons in charge decided whether and when appendectomy was necessary. In total, 1,019 patients were screened for eligibility; 203 patients met inclusion criteria, 126 were accepted to participate, 29 declined, and 48 were missed for inclusion.

RESULTS

The antibiotic group (n = 69) and the control group (n = 57) were comparable at inclusion. Appendectomy at first hospital stay was 28% and 53% for study and control patients (χ2, P < .004). Life table analysis indicated a time-dependent difference in the need for appendectomy during follow-up (P < .03). Antibiotics prevented surgical exploration and appendectomy by 72% to 50% compared to 47% to 37% in the control group across the time course follow-ups between 5 and 1,200 days.

CONCLUSION

Early antibiotic treatment is superior to traditional "wait and see observation" to avoid surgical exploration and appendectomy.

A core outcome set for appendicitis: A consensus approach utilizing modified Delphi methodology

BACKGROUND

Appendicitis is one of the most common pathologies encountered by general and acute care surgeons. The current literature is inconsistent, as it is fraught with outcome heterogeneity, especially in the area of nonoperative management. We sought to develop a core outcome set (COS) for future appendicitis studies to facilitate outcome standardization and future data pooling.

METHODS

A modified Delphi study was conducted after identification of content experts in the field of appendicitis using both the Eastern Association for the Surgery of Trauma (EAST) landmark appendicitis articles and consensus from the EAST ad hoc COS taskforce on appendicitis. The study incorporated three rounds. Round 1 utilized free text outcome suggestions, then in rounds 2 and 3 the suggests were scored using a Likert scale of 1 to 9 with 1 to 3 denoting a less important outcome, 4 to 6 denoting an important but noncritical outcome, and 7 to 9 denoting a critically important outcome. Core outcome status consensus was defined a priori as >70% of scores 7 to 9 and <15% of scores 1 to 3.

RESULTS

Seventeen panelists initially agreed to participate in the study with 16 completing the process (94%). Thirty-two unique potential outcomes were initially suggested in round 1 and 10 (31%) met consensus with one outcome meeting exclusion at the end of round 2. At completion of round 3, a total of 17 (53%) outcomes achieved COS consensus.

CONCLUSION

An international panel of 16 appendicitis experts achieved consensus on 17 core outcomes that should be incorporated into future appendicitis studies as a minimum set of standardized outcomes to help frame future cohort-based studies on appendicitis.

LEVEL OF EVIDENCE

Diagnostic Test or Criteria; Level V.

Role of preoperative in-hospital delay on appendiceal perforation while awaiting appendicectomy (PERFECT): a Nordic, pragmatic, open-label, multicentre, non-inferiority, randomised controlled trial

BACKGROUND

Appendicectomy remains the standard treatment for appendicitis. No international consensus exists on the surgical urgency for acute uncomplicated appendicitis, and recommendations vary from surgery without delay to surgery within 24 h. Longer in-hospital delay has been thought to increase the risk of perforation and further morbidity. Therefore, we aimed to compare the rate of appendiceal perforation in patients undergoing appendicectomy scheduled to two different urgencies (<8 h vs <24 h).

METHODS

In this pragmatic, open-label, multicentre, non-inferiority, parallel, randomised controlled trial in two hospitals in Finland and one in Norway, patients (aged ≥18 years) with presumed uncomplicated acute appendicitis were randomly assigned (1:1) to an appendicectomy scheduled within 8 h or within 24 h to determine whether longer in-hospital delay (time between randomisation and surgical incision) is not inferior to shorter delay. Patients were excluded in cases of pregnancy, suspicion of perforated appendicitis (C-reactive protein level of ≥100 mg/L, fever >38·5°C, signs of complicated appendicitis on imaging studies, or clinical generalised peritonitis), or other reasons requiring prompt surgery. The recruiters were on-duty surgeons who decided to proceed with the appendicectomy. The randomisation sequence was generated using block randomisation with randomly varying block sizes and stratified by hospital districts; neither physicians nor patients were masked to group assignment. The primary outcome was perforated appendicitis diagnosed during surgery analysed in all patients who received an appendicectomy by intention to treat. The absolute difference in rates of perforated appendicitis was compared between the groups. Complications and other safety outcomes were analysed in all patients who received an appendicectomy. A margin of 5 percentage points was used to establish non-inferiority. This trial was registered at ClinicalTrials.gov (NCT04378868) and is closed to accrual.

FINDINGS

Between May 18, 2020, and Dec 31, 2022, 2095 patients were assessed for eligibility, of whom 1822 were randomly assigned to appendicectomy scheduled within 8 h (n=914) or 24 h (n=908). After randomisation, 19 (1%) of 1822 patients were excluded due to protocol violation. 1803 patients were included in the intention-to-treat analyses, 985 (55%) of whom were male and 818 (45%) female. Appendiceal perforation rate was similar between groups (77 [8%] of 907 patients assigned to the <8 h group and 81 [9%] of 896 patients assigned to the <24 h group; absolute risk difference 0·6% [95% CI -2·1 to 3·2], p=0·68; risk ratio 1·065, 95% CI 0·790 to 1·435). No significant difference was found between the complication rates within 30 days (66 [7%] of 907 patients in the <8 h group vs 56 [6%] of 896 patients in the <24 h group; difference -1·0% [-3·3 to 1·3]; p=0·39), and no deaths occurred during this follow-up period.

INTERPRETATION

In patients with presumed uncomplicated acute appendicitis, scheduling appendicectomy within 24 h does not increase the risk of appendiceal perforation compared with scheduling appendicectomy within 8 h. The results can be used to allocate operating room resources, for example postponing night-time appendicectomy to daytime.

FUNDING

The Finnish Medical Foundation, Mary and Georg Ehrnrooth's Foundation, Biomedicum Helsinki Foundation, and the Finnish Government.

Outpatient Non-operative Management of Uncomplicated Acute Appendicitis: A Non-inferiority Study

INTRODUCTION

Non-operative management (NOM) of uncomplicated acute appendicitis is a well-established alternative to upfront surgery. The administration of intravenous broad-spectrum antibiotics is usually performed in hospital, and only one study described outpatient NOM. The aim of this multicentre retrospective non-inferiority study was to evaluate both safety and non-inferiority of outpatient compared to inpatient NOM in uncomplicated acute appendicitis.

METHODS

The study included 668 consecutive patients with uncomplicated acute appendicitis. Patients were treated according to the surgeon's preference: 364 upfront appendectomy, 157 inpatient NOM (inNOM), and 147 outpatient NOM (outNOM). The primary endpoint was the 30-day appendectomy rate, with a non-inferiority limit of 5%. Secondary endpoints were negative appendectomy rate, 30-day unplanned emergency department (ED) visits, and length of stay.

RESULTS

30-day appendectomies were 16 (10.9%) in the outNOM group and 23 (14.6%) in the inNOM group (p = 0.327). OutNOM was non-inferior to inNOM with a risk difference of-3.80% 97.5% CI (- 12.57; 4.97). No difference was found between inNOM and outNOM groups for the number of complicated appendicitis (3 vs. 5) and negative appendectomy (1 vs. 0). Twenty-six (17.7%) outNOM patients required an unplanned ED visit after a median of 1 (1-4) days. In the outNOM group, the mean cumulative in-hospital stay was 0.89 (1.94) days compared with 3.94 (2.17) days in the inNOM group (p < 0.001).

CONCLUSIONS

Outpatient NOM was non-inferior to inpatient NOM with regard to the 30-day appendectomy rate, while a shorter hospital stay was found in the outNOM group. Further, studies are required to confirm these findings.

Spontaneous Resolution of Uncomplicated Appendicitis may Explain Increase in Proportion of Complicated Appendicitis During Covid-19 Pandemic: a Systematic Review and Meta-analysis

BACKGROUND

Reports of an increased proportion of complicated appendicitis during the Covid-19 pandemic suggest a worse outcome due to delay secondary to the restrained access to health care, but may be explained by a concomitant decrease in uncomplicated appendicitis. We analyze the impact of the pandemic on the incidences of complicated and uncomplicated appendicitis.

METHOD

We did a systematic literature search in the PubMed, Embase and Web Of Science databases on December 21, 2022 with the search terms (appendicitis OR appendectomy) AND ("COVID" OR SARS-Cov2 OR "coronavirus"). Studies reporting the number of complicated and uncomplicated appendicitis during identical calendar periods in 2020 and the pre-pandemic year(s) were included. Reports with indications suggesting a change in how the patients were diagnosed and managed between the two periods were excluded. No protocol was prepared in advance. We did random effects meta-analysis of the change in proportion of complicated appendicitis, expressed as the risk ratio (RR), and of the change in number of patients with complicated and uncomplicated appendicitis during the pandemic compared with pre-pandemic periods, expressed as the incidence ratio (IR). We did separate analyses for studies based on single- and multi-center and regional data, age-categories and prehospital delay.

RESULTS

The meta-analysis of 100,059 patients in 63 reports from 25 countries shows an increase in the proportion of complicated appendicitis during the pandemic period (RR 1.39, 95% confidence interval (95% CI 1.25, 1.53). This was mainly explained by a decreased incidence of uncomplicated appendicitis (incidence ratio (IR) 0.66, 95% CI 0.59, 0.73). No increase in complicated appendicitis was seen in multi-center and regional reports combined (IR 0.98, 95% CI 0.90, 1.07).

CONCLUSION

The increased proportion of complicated appendicitis during Covid-19 is explained by a decrease in the incidence of uncomplicated appendicitis, whereas the incidence of complicated appendicitis remained stable. This result is more evident in the multi-center and regional based reports. This suggests an increase in spontaneously resolving appendicitis due to the restrained access to health care. This has important principal implications for the management of patients with suspected appendicitis.

One-year follow-up of conservative management of appendicitis: results from a single centre during extended lockdown in the COVID-19 pandemic

INTRODUCTION

Conservative management with antibiotics was recommended by the UK Surgical Royal Colleges early in the COVID-19 pandemic as the first-line treatment for acute uncomplicated appendicitis.

METHODS

This is a prospective single-centre cohort study of patients aged 16 years or over, diagnosed clinically and confirmed radiologically with acute appendicitis in a secondary care setting who were initially treated conservatively with antibiotics. The primary outcome was the response to conservative management with antibiotics. Secondary outcomes were: antibiotic duration; operative rates; surgical approach (open, laparoscopic or conversion to open); complication rates; COVID-19 positive rate; rates of readmission within 12 months; and length of hospital stay.

RESULTS

A total of 109 patients were included in the study, 67 of whom were male. Median age was 37 (range 17-93) years. A further 28 patients were excluded because of a decision to manage operatively on the index admission or because of other diagnoses. Thirty-three patients (30.3%) had surgery on the index admission after failed conservative management and 15 (13.8%) had surgery on readmission. On histology, 32/48 patients (66.7%) had a diagnosis of complicated appendicitis and 18/48 (37.5%) had a confirmed appendicolith.

CONCLUSIONS

There was a high readmission rate (47/109; 43.1%) for surgery, a radiological drain or conservative management within the first year following initial conservative management. There is a significant risk of recurrence of symptoms, particularly in the presence of an appendicolith. Laparoscopic appendicectomy should be the first-line treatment, with conservative management reserved for patients with acute uncomplicated appendicitis who are COVID-19 positive or have comorbidities.

Probiotics, the Immune Response and Acute Appendicitis: A Review

Acute appendicitis is a common reason for admission to the Emergency Department (ED). It affects almost 70% of people under 30 years of age and 10% over 60 years of age. Its diagnosis includes the combination of clinical signs, laboratory tests and imaging. For years, surgical appendectomy has been the first-line therapy for acute appendicitis, but currently the management has shown some changes, in particular in patients with uncomplicated appendicitis. Recent studies have investigated the use of probiotics as an adjunctive therapy with promising results in conferring health benefits to patients with acute appendicitis. The aim of our review is to summarize the results of clinical studies about probiotics and the immunological response in acute appendicitis, discussing the limitations and future directions of this research.

Association of the Bacteria of the Vermiform Appendix and the Peritoneal Cavity with Complicated Acute Appendicitis in Children

BACKGROUND

Primary infection has been questioned as the pathogenetic cause of acute appendicitis. We attempted to identify the bacteria involved and to investigate if their species, types, or combinations affected the severity of acute appendicitis in children.

METHODS

Samples from both the appendiceal lumen and the peritoneal cavity of 72 children who underwent appendectomy were collected to perform bacterial culture analysis. The outcomes were studied to identify if and how they were associated with the severity of the disease. Regression analysis was performed to identify any risk factors associated with complicated appendicitis.

RESULTS

Escherichia coli, Pseudomonas aeruginosa, and Streptococcus species were the most common pathogens found in the study population. The same microorganisms, either combined or separate, were the most common in the appendiceal lumen and the peritoneal cavity of patients with complicated appendicitis. Gram-negative bacteria and polymicrobial cultures in the peritoneal fluid and in the appendiceal lumen were associated with complicated appendicitis. Polymicrobial cultures in the peritoneal cavity presented a four times higher risk of complicated appendicitis.

CONCLUSIONS

Polymicrobial presentation and Gram-negative bacteria are associated with complicated appendicitis. Antibiotic regimens should target the combinations of the most frequently identified pathogens, speculating the value of early antipseudomonal intervention.

Appendiceal Endometriosis: A Comprehensive Review of the Literature

Objective: the purpose of this review was to evaluate the prevalence of appendiceal endometriosis and the safety of concomitant appendectomy in women with endometriosis or pelvic pain. Materials and Methods: We searched the electronic databases Medline (PubMed), Scopus, Embase, and Web of Science (WOS). The search was not subject to any limitation in terms of time or method. The primary research question was: what is the prevalence of appendiceal endometriosis? The secondary research question was: is it safe to perform appendectomy during surgery for endometriosis? Publications that reported data about appendiceal endometriosis or appendectomy in women with endometriosis were reviewed regarding the inclusion criteria. Results: We found 1418 records. After review and screening, we included 75 studies published between 1975 and 2021. With regard to the first question of the review, we found 65 eligible studies and divided these into the following two categories: (a) endometriosis of the appendix presenting as acute appendicitis, and (b) endometriosis of the appendix as an incidental finding in gynecological surgery. Forty-four case reports described appendiceal endometriosis in women who were admitted for the treatment of pain in the right-sided lower abdomen. Endometriosis of the appendix was observed in 2.67% (range, 0.36-23%) of women who were admitted due to acute appendicitis. In addition, appendiceal endometriosis was an incidental finding during gynecological surgery in 7.23% of cases (range, 1-44.3%). With regard to the second question of the review, which was the safety of appendectomy in women with endometriosis or pelvic pain, we found 11 eligible studies. Reviewed cases had no significant intraoperative or follow-up complications during the 12 weeks. Conclusion: Based on the reviewed studies, coincidental appendectomy appears reasonably safe and was associated with no complications in the cases reviewed for the present report.

Three Centuries of Appendicectomy

BACKGROUND

Save for the contribution of Charles McBurney, who described his eponymous point and the appendicectomy incision, the history of appendicectomy is largely unknown among the medical profession. This review traces the history from the first anatomical depiction of the appendix to the development of open appendicectomy and the recent minimally invasive and non-operative methods.

METHODS

Historical articles, monographs and books containing anatomical descriptions of the vermiform appendix and reports of appendicitis and its surgical treatment were retrieved after searching the PubMed, Google Scholar and Embase databases from their inception to 31 March 2022.

RESULTS

The first inadvertent appendicectomy was performed during an operation for a groin hernia by Cookesley in 1731, and Mestivier was the first to drain a right iliac fossa abscess, due to appendicitis, in 1757. Krönlein performed the first appendicectomy for acute appendicitis in 1884 but his patient died. The first successful appendicectomy for acute appendicitis leading to patient survival was by Morton in 1887. In 1976, Wirschafter and Kaufman performed an inadvertent colonoscopic appendicectomy and, in 1980, Semm carried out the first laparoscopic appendicectomy. The first appendicectomy via a natural orifice (transgastric) appendicectomy was by Rao and Reddy in 2004.

CONCLUSION

This historical review charts the development of surgical knowledge concerning the management of appendicitis, from the first anatomical drawings of the appendix and descriptions of appendicitis to the development of surgical and conservative treatments up to the present day. It also corrects some inaccuracies of attribution in previous historical reviews.

Application of Artificial Neural Network Models to Differentiate Between Complicated and Uncomplicated Acute Appendicitis

Preoperative prediction of complicated appendicitis is challenging, and many clinical tools are developed to predict complicated appendicitis. This study evaluated whether a supervised learning method can recognize complicated appendicitis in emergency department (ED). Consecutive patients with acute appendicitis presenting to the ED were enrolled and included into training and testing datasets at a ratio of 70:30. The multilayer perceptron artificial neural network (ANN) models were trained to perform binary outcome classification between uncomplicated and complicated acute appendicitis. Measures of sensitivity, specificity, positive and negative likelihood ratio (LR + and LR-), and a c statistic of a receiver of operating characteristic curve were used to evaluate an ANN model. The simplest ANN model by Bröker et al. including the C-reactive protein (CRP) and symptom duration as variables achieved a c statistic value of 0.894. The ANN models developed by Avanesov et al. including symptom duration, appendiceal diameter, periappendiceal fluid, extraluminal air, and abscess as variables attained a high diagnostic performance (a c statistic value of 0.949) and good efficiency (sensitivity of 78.6%, specificity of 94.5%, LR + of 14.29, LR- of 0.23 in the testing dataset); and our own model by H.A. Lin et al. including the CRP level, neutrophil-to-lymphocyte ratio, fat-stranding sign, appendicolith, and ascites exhibited high accuracy (c statistic of 0.950) and outstanding efficiency (sensitivity of 85.7%, specificity of 91.7%, LR + of 10.36, LR- of 0.16 in the testing dataset). The ANN models developed by Avanesov et al. and H.A. Lin et al. developed model exhibited a high diagnostic performance.

Non-culture-based studies of the appendiceal microbiota: a systematic review

Aims: To review studies examining the appendiceal microbiota and microbial changes in acute appendicitis. Methods: After a systematic literature search, 11 studies examining the appendiceal microbiota (414 samples) using non-culture-based methods were included. Results: The appendiceal microbiota showed decreased α-diversity compared with fecal microbiota. Inflamed and uninflamed appendices showed differences in β-diversity, and there was an increased abundance of oral-associated bacteria in inflamed versus uninflamed appendices. Conclusion: The appendiceal microbiota exhibits lower α-diversity than the fecal microbiota, with an increased abundance of oral-associated bacteria. Compared with uninflamed appendices, the appendix microbiota in acute appendicitis also showed increased abundance of oral-associated bacteria, but no bacterial profile unique to either complicated or uncomplicated appendicitis was found.

Infection or Inflammation: Are Uncomplicated Acute Appendicitis, Acute Cholecystitis, and Acute Diverticulitis Infectious Diseases?

Background: It is recognized increasingly that common surgical infections of the peritoneal cavity may be treated with antibiotic agents alone, or source control surgery with short-course antimicrobial therapy. By extension, testable hypotheses have emerged that such infections may not actually be infectious diseases, but rather represent inflammation that can be treated successfully with neither surgery nor antibiotic agents. The aim of this review is to examine extant data to determine which of uncomplicated acute appendicitis (uAA), uncomplicated acute calculous cholecystitis (uACC), or uncomplicated mild acute diverticulitis (umAD) might be amenable to management using supportive therapy alone, consistent with the principles of antimicrobial stewardship. Methods: Review of pertinent English-language literature and expert opinion. Results: Only two small trials have examined whether uAA can be managed with observation and supportive therapy alone, one of which is underpowered and was stopped prematurely because of challenging patient recruitment. Data are insufficient to determine the safety and efficacy of non-antibiotic therapy of uAA. Uncomplicated acute calculous cholecystitis is not primarily an infectious disease; infection is a secondary phenomenon. Even when bactibilia is present, there is no high-quality evidence to suggest that mild disease should be treated with antibiotic agents. There is evidence to indicate that antibiotic prophylaxis is indicated for urgent/emergency cholecystectomy for uACC, but not in the post-operative period. Uncomplicated mild acute diverticulitis, generally Hinchey 1a or 1b in current nomenclature, does not benefit from antimicrobial agents based on multiple clinical studies. The implication is that umAD is inflammatory and not an infectious disease. Non-antimicrobial management is reasonable. Conclusions: Among the considered disease entities, the evidence is strongest that umAD is not an infectious disease and can be treated without antibiotic agents, intermediate regarding uACC, and lacking for uAA. A plausible hypothesis is that these inflammatory conditions are related to disruption of the normal microbiome, resulting in dysbiosis, which is defined as an imbalance of the natural microflora, especially of the gut, that is believed to contribute to a range of conditions of ill health. As for restorative pre- or probiotic therapy to reconstitute the microbiome, no recommendation can be made in terms of treatment, but it is not recommended for prevention of primary or recurrent disease.

Is it time for global adoption of endoscopic retrograde appendicitis therapy of acute appendicitis?

Acute appendicitis is a common abdominal surgical emergency worldwide. Abraham Groves performed the first documented open appendectomy in 1883. Although appendectomy is still the most effective treatment in cases of acute appendicitis, it causes a range of complications and carries the risk of negative appendectomy. In the awake of covid-19, the latest guidelines recommend antibiotic therapy as an acceptable first line treatment for acute appendicitis. However, patients treated with antibiotics have a recurrence risk of up to 30% at 1 year. Endoscopic retrograde appendicitis therapy (ERAT) has emerged as promising non-invasive treatment modality for acute uncomplicated appendicitis (AUA) which involves cannulation, appedicography, appendiceal stone extraction, appendiceal lumen irrigation, and stent insertion. ERAT aims to relieve the cause of appendicitis (e.g., obstruction or stenosis of the appendiceal lumen) and thus effectively prevent the recurrence of appendicitis. In addition, it can make a definitive diagnosis of acute appendicitis during endoscopic retrograde appendicography. Studies have shown that 93.8 to 95% of AUA patients did not have a recurrence following ERAT. In this study, we aim to summarize the current body of evidence on ERAT to situate it alongside currently established therapies for acute appendicitis, in particular, AUA.

A randomized, controlled multicenter feasibility pilot trial on imaging confirmed uncomplicated acute appendicitis: Appendectomy vs. symptomatic treatment in pediatric patients (the APPSYPP) trial study protocol

INTRODUCTION

Imaging-confirmed uncomplicated acute appendicitis can be effectively and safely treated with antibiotics in most adults and children. Symptomatic treatment may have similar efficacy and safety.

METHODS AND ANALYSIS

The APPSYPP trial is a randomized national multicenter feasibility superiority pilot study comparing appendectomy with symptomatic treatment in children with imaging-confirmed uncomplicated acute appendicitis.

INCLUSION CRITERIA

1) age ≥ 7 and < 16 years, 2) imaging-confirmed uncomplicated acute appendicitis and 3) CRP ≤ 65 mg/l. Patients are randomized to receive emergency laparoscopic appendectomy or symptomatic treatment. To ensure patient safety, symptomatically treated patients are hospitalized for at least 24 h receiving standard practice intravenous fluids and analgesics according to standard clinical practice. Primary outcome is 30-day treatment success defined by the absence of any treatment failure criteria. In appendectomy, treatment failure is defined as normal appendiceal histopathology or any postintervention complication requiring general anesthesia. In symptomatic treatment, treatment failure is defined as 1) inability for hospital discharge without appendectomy within 48 h after randomization with a finding of histopathologically inflamed appendix, 2) appendectomy during the initial hospital stay due to clinical progression of appendicitis with complicated acute appendicitis both histopathologically and surgically, 3) appendectomy with a histopathological finding of acute appendicitis after hospital discharge, or 4) any complication of appendicitis requiring general anesthesia. Detailed predefined secondary outcomes will be analyzed.

ETHICS AND DISSEMINATION

Study was approved by Ethics Committee of Helsinki University Hospital (ID:HUS/1993/2021), conducted in compliance with the declaration of Helsinki with results disseminated in peer-reviewed scientific journals.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT05289713).

STRENGTHS AND LIMITATIONS OF THIS STUDY

Is acute appendicitis complicated or uncomplicated? Approaching the question via computed tomography

Background

The distinction between complicated and uncomplicated appendicitis is very important for the selection of the treatment method.

Purpose

To investigate the sensitivity and specificity of computed tomography (CT) in differentiating between complicated and uncomplicated appendicitis to demonstrate that false negativity in differentiating these cases can be reduced when CT findings are incorporated into the clinical evaluation of patients.

Material and Methods

All patients aged ≥18 years who underwent appendectomy at Malatya Training and Research Hospital in 2020 and 2021 were retrospectively screened. Of them, 283 patients were included in the study who had undergone CT before the operation. Patients with appendicitis were divided into two groups: complicated and uncomplicated, according to the results of their pathology tests. Demographic data, laboratory results, and CT images of the patients were evaluated.

Results

The patients with complicated appendicitis had a significantly higher mean age ( P<0.001). The most common CT findings in patients with complicated appendicitis were moderate or severe peri-appendiceal fat stranding (PFS) and appendix wall enhancement defect (AWD). The findings with the highest sensitivity were PFS (77.9%) and AWD (69.4%). Although abscess, phlegmon, and peri-appendiceal air had the highest specificity (100%), these findings were the ones with the lowest sensitivity. According to the scoring system was developed for the differential diagnosis, CT had a sensitivity of 83.3% and a specificity of 79.2%.

Conclusion

Based on the sensitivity and specificity values measured for CT according to the findings of our study, the scoring system may be useful for the differential diagnosis of complicated appendicitis.

Non-operative management of acute appendicitis in children

Appendicitis is one of the most common surgical emergencies in children and adults. Appendectomy as the standard care has been challenged in the recent years with growing evidence about non-operative treatment as a potential primary treatment in patients presenting with signs and symptoms suggestive of acute appendicitis. This review aims to establish where the recent research stands regarding conservative treatment of acute appendicitis, especially in children. There are several studies that report the potential safety and efficacy of treating acute appendicitis non-operatively. Several studies have challenged the concept of acute appendicitis being a progressive disease that always ends in perforation, rather than a disease that can present as different forms with only a defined number of cases progressing to perforation. The lack of randomized controlled studies is a limitation and well-designed randomized controlled trials are needed to determine the role of non-operative management of acute appendicitis in children.

Comparación de la seguridad y la eficacia del uso de antibióticos frente a la apendicectomía en el tratamiento de la apendicitis no complicada en adultos. Revisión sistemática y metaanálisis

Introducción. La apendicitis aguda es una emergencia quirúrgica frecuente, en la cual el tratamiento de tipo conservador basado en antibióticos se ha identificado como una opción terapéutica que necesita seguir siendo estudiada. El objetivo de este estudio fue determinar las diferencias en seguridad y eficacia del uso de antibióticos en comparación con la apendicectomía en adultos con apendicitis no complicada. Métodos. Revisión sistemática y metaanálisis. Se encontraron 452 estudios; después de una selección, 45 se evaluaron en texto completo y 15 para calidad metodológica; 11 estudios fueron seleccionados y 9 incluidos en el metaanálisis. Resultados. Se contó con 3186 participantes, de los cuales 1512 fueron tratados con terapia antibiótica y 1674 sometidos a apendicectomía. Se identificó estancia hospitalaria más corta en los pacientes sometidos a apendicectomía (SMD: 0,28; IC95%: 0,14 a 0,41). Para los pacientes tratados con terapia antibiótica, se evidenció puntajes de riesgo menores en las escalas de diagnóstico de apendicitis (SMD: -0,13; IC95%: -0,22 a -0,04), menor éxito terapéutico en un 16 % (RR: 0,84; IC95%: 0,77 a 0,92) y reducción del riesgo de complicaciones del 63 % (RR: 0,37; IC95%: 0,25 a 0,53). Se encontró alta heterogeneidad y riesgo de sesgo de publicación. Conclusiones. La terapia antibiótica necesita mayor evidencia para desenlaces como calidad de vida, satisfacción, dolor, o complicaciones específicas, entre otros, que permitan hacer comparaciones más contundentes. Los pacientes que consideren el manejo conservador necesitan ser adecuadamente asesorados y monitorizados para optimizar sus posibilidades de resultados favorables y la oportuna identificación de complicaciones que necesiten de otros abordajes.

Blood culture positivity in patients with acute appendicitis: A propensity score-matched prospective cohort study

BACKGROUND AND OBJECTIVE

The prevalence of bacteremia in acute appendicitis is unknown. We aimed to assess prevalence and predictive factors of bacteremia in adult patients with appendicitis.

METHODS

In this prospective propensity score-matched cohort study, patients were recruited as part of one single-center prospective observational study assessing appendicitis microbiology in concurrence with two randomized controlled trials on non-operative treatment of uncomplicated acute appendicitis. All patients evaluated for enrollment in these three trials between April 2017 and December 2018 with both a confirmed diagnosis of appendicitis and available blood culture on admission were included in this study. Potential predictive factors of bacteremia (age, sex, body mass index (BMI), body temperature, C-reactive protein (CRP), leukocyte count, comorbidities, symptom duration, and appendicitis severity) were assessed. Prevalence of bacteremia was determined by all available blood cultures followed by propensity score matching using sex, age, BMI, CRP, leukocyte count, and body temperature of the patients without available blood culture.

RESULTS

Out of the 815 patients with appendicitis, 271 patients had available blood culture and the prevalence of bacteremia was 12% (n = 33). Based on propensity score estimation, the prevalence of bacteremia in the whole prospective appendicitis cohort was 11.1%. Bacteremia was significantly more frequent in complicated acute appendicitis (15%; 29/189) compared with uncomplicated acute appendicitis (5%; 4/82) (p = 0.015). Male sex (p = 0.024) and higher body temperature (p = 0.0044) were associated with bacteremia.

CONCLUSIONS

Estimated prevalence of bacteremia in patients with acute appendicitis was 11.1%. Complicated appendicitis, male sex, and higher body temperature were associated with bacteremia in acute appendicitis.

The Diagnostic Differentiation Challenge in Acute Appendicitis: How to Distinguish between Uncomplicated and Complicated Appendicitis in Adults

(1) Background: How to best define, diagnose and differentiate uncomplicated from complicated acute appendicitis remains debated. Hence, the aim of this review was to present an overview of the current knowledge and emerging field of acute appendicitis with a focus on the diagnostic differentiation of severity currently subject to ongoing investigations. (2) Methods: We conducted a PubMed search using the MeSH terms “appendicitis AND severity” and “appendicitis AND classification”, with a focus on studies calling appendicitis as ‘uncomplicated’ or ‘complicated’. An emphasis on the last 5 years was stressed, with further studies selected for their contribution to the theme. Further studies were retrieved from identified full-text articles and included per the authors’ discretion. (3) Results: The assumption that appendicitis invariably will proceed to perforation has been outdated. Both uncomplicated and complicated appendicitis exist with likely different pathophysiology. Hence, this makes it important to differentiate disease severity. Clinicians must diagnose appendicitis, but, in the next step, also differentiate between uncomplicated and complicated appendicitis in order to allow for management decisions. Diagnostic accuracy without supportive imaging is around 75–80% and, based on clinical judgement and blood tests alone, the negative appendectomy rate has been described as high as 36%. More research is needed on available biomarkers, and the routine use of imaging still remains debated. Scoring systems have the potential to improve diagnostic accuracy, but no scoring system has yet been validated for differentiating disease severity. Currently, no universally agreed definition exists on what constitutes a complicated appendicitis. (4) Conclusions: Uncomplicated and complicated appendicitis appear to have different pathophysiology and should be treated differently. The differentiation between uncomplicated and complicated appendicitis remains a diagnostic challenge.

Randomized clinical trials comparing antibiotic therapy with appendicectomy for uncomplicated acute appendicitis: meta-analysis

BACKGROUND

This aim of this study was to provide an updated meta-analysis comparing antibiotic therapy with appendicectomy in adults (16 years or older) with uncomplicated acute appendicitis.

METHODS

A search for randomized clinical trials comparing antibiotic therapy with appendicectomy in adults with uncomplicated acute appendicitis from inception to 3 October 2021 in MEDLINE, Embase and CENTRAL with no language constraints was performed. Studies were excluded if they included paediatric participants or those with complicated appendicitis. Data on complications of treatment, treatment efficacy (defined in the antibiotic group as not undergoing appendicectomy within 1 year of enrolment, versus surgery without complications or no negative histology in the appendicectomy group), readmissions, and length of stay (LOS) were presented.

RESULTS

Eight RCTs involving 3203 participants (1613 antibiotics/1590 appendicectomy; 2041 males/1162 females) were included. There was no significant benefit of antibiotic treatment on complication rates (risk ratio (RR) 0.66, 95 per cent c.i. 0.41 to 1.04). Antibiotics had a reduced treatment efficacy compared with appendicectomy (RR 0.75, 95 per cent c.i. 0.63 to 0.89). Antibiotic treatment at 1 year was successful in 1016 of 1613 (62.9 per cent) participants. There was a six-fold increase in hospital readmissions within 1 year of enrolment in participants receiving antibiotic treatment (RR 6.28, 95 per cent c.i. 2.87 to 13.74). There was no difference in index admission LOS (mean difference 0.15 days (95 per cent c.i. -0.05 to 0.35)).

CONCLUSIONS

Earlier optimism regarding the benefits of antibiotic therapy for uncomplicated acute appendicitis does not persist at the same level now that further, large trials have been included. If antibiotic treatment is to be offered routinely as first-line therapy, patients should be counselled appropriately.

Antibiotic treatment for appendicitis in Norway and Sweden: a nationwide survey on treatment practices

Background

Appendicitis is one of the most common causes of acute abdomen. Uncomplicated appendicitis is as an inflamed appendix without perforation, gangrene or abscess formation. Recent trials show that one can safely treat uncomplicated appendicitis with antibiotics, given patient approval and appropriate follow-up. A recent study has also indicated no difference between antibiotic treatment and placebo. Our aim was to investigate if Norwegian and Swedish surgical departments treat uncomplicated appendicitis with antibiotics and to explore their opinions on this treatment practice.

Methods

A questionnaire was distributed to all heads of department in hospitals that treat appendicitis in Norway and Sweden. Answers were collected using a REDCap survey. Answers were compared between centers and nations and the results were presented anonymously.

Results

We sent the questionnaire to 94 eligible recipients and received 61 (65%) answers. In total, 8/61 (13%) departments stated that they have established antibiotic treatment as sole treatment for uncomplicated appendicitis. Almost half of the responders stated that they have used antibiotics sporadically to treat uncomplicated appendicitis. Lack of evidence and guidelines were noted as reasons why antibiotic treatment has not been implemented as sole treatment.

Conclusions

Most Norwegian and Swedish departments have not implemented antibiotic treatment as the sole treatment for uncomplicated appendicitis. Despite several recent large trials on this subject, lack of evidence and guidelines was the most frequently reported reason in our survey.

Optimising the treatment for uncomplicated acute appendicitis (OPTIMA trial): a protocol for a multicentre, randomised, double-blinded placebo-controlled study

INTRODUCTION

Emerging evidence has shown that an antibiotic first strategy is a viable treatment option for uncomplicated acute appendicitis (AA). Although there has recently been an interest and increase in the use of antibiotics as the primary strategy for treating uncomplicated AA, there is no consensus regarding the optimum antibiotic regimen. In particular, the long-term outcomes of different antibiotic regimens, such as the recurrence rate, still lack evidence. Given that the flora of the appendix is mainly anaerobic bacteria, we hypothesised that antianaerobe regimens could decrease the recurrence rate compared with those that did not include antianaerobic antibiotics.

METHODS AND ANALYSIS

The OPTIMA(Optimising the treatment for uncomplicated acute appendicitis) trial is a multicentre, double-blinded placebo-controlled superiority randomised study aimed to evaluate the role of antianaerobic antibiotics in the resolution of uncomplicated AA. Patients (18-65 years) with uncomplicated AA (without gangrenous, perforated appendicitis, appendiceal abscess, or appendiceal fecaliths) are eligible for inclusion. The primary endpoint of this study is the success rate of the treatment, defined as the resolution of AA resulting in discharge from the hospital without surgical intervention and recurrent symptoms within one year. Secondary endpoints include mortality, postintervention complications, recurrent symptoms up to one year after treatment, hospital stay, sick leave, treatment cost, pain symptom scores and quality of life. Data are reported as the number of cases (%), median (range) and relative risk, which will be analysed using the Mann-Whitney U test or χ2 test, as appropriate. P-value<0.05 will be considered significant.

ETHICS AND DISSEMINATION

The protocol has been approved by the Ethics Committee of Jinling Hospital on 13 November 2018 (2018NZKY-027-01). The trial findings will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR1800018896.

Efficacy and Safety of Non-Operative Management of Uncomplicated Acute Appendicitis Compared to Appendectomy: An Umbrella Review of Systematic Reviews and Meta-Analyses

BACKGROUND

Non-operative management (NOM) of uncomplicated acute appendicitis (AA) has been introduced as an alternative to appendectomy. This umbrella review aimed to provide an overview of the efficacy and safety of NOM of uncomplicated AA in the published systematic reviews.

METHODS

This umbrella review has been reported in line with the PRISMA guidelines and umbrella review approach. Systematic reviews with and without meta-analyses on the efficacy of NOM of AA were analyzed. The quality of the reviews was assessed with the AMSTAR 2 tool. The main outcomes measures were the treatment failure and complication rates of NOM and hospital stay as compared to appendectomy.

RESULTS

Eighteen systematic reviews were included to this umbrella review. Eight reviews documented higher odds of failure with NOM, whereas two reviews revealed similar odds of failure. Six reviews reported lower odds of complications with NOM, six reported similar odds, and one reported lower odds of complications with surgery. Eight reviews reported similar hospital stay between NOM and appendectomy, one reported longer stay with NOM and another reported shorter stay with NOM. Pooled analyses showed that NOM was associated with higher treatment failure overall, in children-only, adults only, and RCTs-only meta-analyses. NOM was associated with lower complications overall, yet children-only and RCTs-only analyses revealed similar complications to surgery. NOM was associated with shorter stay in the overall and adult-only analysis, but not in the children-only analysis.

CONCLUSIONS

NOM of AA is associated with higher treatment failure, marginally lower rate of complications and shorter stay than appendectomy.

Optimising diagnostics to discriminate complicated from uncomplicated appendicitis: a prospective cohort study protocol

INTRODUCTION

Growing evidence is showing that complicated and uncomplicated appendicitis are two different entities that may be treated differently. A correct diagnosis of the type of appendicitis is therefore essential. The Scoring system of Appendicitis Severity (SAS) combines clinical, laboratory and imaging findings. The SAS rules out complicated appendicitis in 95% (negative predictive value, NPV) and detects 95% (sensitivity) of patients with complicated appendicitis in adults suspected of acute appendicitis. However, this scoring system has not yet been validated externally. In this study, we aim to provide a prospective external validation of the SAS in a new cohort of patients with clinical suspicion of appendicitis. We will optimise the score when necessary.

METHODS AND ANALYSIS

The SAS will be validated in 795 consecutive adult patients diagnosed with acute appendicitis confirmed by imaging. Data will be collected prospectively in multiple centres. The predicted diagnosis based on the SAS score will be compared with the combined surgical and histological diagnosis. Diagnostic accuracy for ruling out complicated appendicitis will be calculated. If the SAS does not reach a sensitivity and NPV of 95% in its present form, the score will be optimised. After optimisation, a second external validation will be performed in a new group of 328 patients. Furthermore, the diagnostic accuracy of the clinical perspective of the treating physician for differentiation between uncomplicated and complicated appendicitis and the patient's preferences for different treatment options will be assessed.

ETHICS AND DISSEMINATION

Ethical approval was granted by the Amsterdam UMC Medical Ethics Committee (reference W19_416 # 19.483). Because of the observational nature of this study, the study does not fall under the scope of the Medical Research Involving Human Subjects Act. Results will be presented in peer-reviewed journals. This protocol is submitted for publication before analysis of the results.

Writing Group for the CODA Collaborative, Monsell SE, Voldal EC, Davidson GH, Fischkoff K, Coleman N, Bizzell B, Price T, Narayan M, Siparsky N, Thompson CM, Ayoung-Chee P, Odom SR, Sanchez S, Drake FT, Johnson J, Cuschieri J, Evans HL, Liang MK, McGrane K, Hatch Q, Victory J, Wisler J, Salzberg M, Ferrigno L, Kaji A, DeUgarte DA, Gibbons MM, Alam HB, Scott J, Kao LS, Self WH, Winchell RJ, Villegas CM, Talan DA, Kessler LG, Lavallee DC, Krishnadasan A, Lawrence SO, Comstock B, Fannon E, Flum DR, Heagerty PJ. Patient Factors Associated With Appendectomy Within 30 Days of Initiating Antibiotic Treatment for Appendicitis

IMPORTANCE

Use of antibiotics for the treatment of appendicitis is safe and has been found to be noninferior to appendectomy based on self-reported health status at 30 days. Identifying patient characteristics associated with a greater likelihood of appendectomy within 30 days in those who initiate antibiotics could support more individualized decision-making.

OBJECTIVE

To assess patient factors associated with undergoing appendectomy within 30 days of initiating antibiotics for appendicitis.

DESIGN, SETTING, AND PARTICIPANTS

In this cohort study using data from the Comparison of Outcomes of Antibiotic Drugs and Appendectomy (CODA) randomized clinical trial, characteristics among patients who initiated antibiotics were compared between those who did and did not undergo appendectomy within 30 days. The study was conducted at 25 US medical centers; participants were enrolled between May 3, 2016, and February 5, 2020. A total of 1552 participants with acute appendicitis were randomized to antibiotics (776 participants) or appendectomy (776 participants). Data were analyzed from September 2020 to July 2021.

EXPOSURES

Appendectomy vs antibiotics.

MAIN OUTCOMES AND MEASURES

Conditional logistic regression models were fit to estimate associations between specific patient factors and the odds of undergoing appendectomy within 30 days after initiating antibiotics. A sensitivity analysis was performed excluding participants who underwent appendectomy within 30 days for nonclinical reasons.

RESULTS

Of 776 participants initiating antibiotics (mean [SD] age, 38.3 [13.4] years; 286 [37%] women and 490 [63%] men), 735 participants had 30-day outcomes, including 154 participants (21%) who underwent appendectomy within 30 days. After adjustment for other factors, female sex (odds ratio [OR], 1.53; 95% CI, 1.01-2.31), radiographic finding of wider appendiceal diameter (OR per 1-mm increase, 1.09; 95% CI, 1.00-1.18), and presence of appendicolith (OR, 1.99; 95% CI, 1.28-3.10) were associated with increased odds of undergoing appendectomy within 30 days. Characteristics that are often associated with increased risk of complications (eg, advanced age, comorbid conditions) and those clinicians often use to describe appendicitis severity (eg, fever: OR, 1.28; 95% CI, 0.82-1.98) were not associated with odds of 30-day appendectomy. The sensitivity analysis limited to appendectomies performed for clinical reasons provided similar results regarding appendicolith (adjusted OR, 2.41; 95% CI, 1.49-3.91).

CONCLUSIONS AND RELEVANCE

This cohort study found that presence of an appendicolith was associated with a nearly 2-fold increased risk of undergoing appendectomy within 30 days of initiating antibiotics. Clinical characteristics often used to describe severity of appendicitis were not associated with odds of 30-day appendectomy. This information may help guide more individualized decision-making for people with appendicitis.

The appendix‐mucosal immunity and tolerance in the gut: consequences for the syndromes of appendicitis and its epidemiology

The cause of appendicitis is unknown. A review is presented across diverse sources relating to the biology of the appendix and its perturbations. A mechanistic model of the function of the appendix is presented, and its application to the syndromes and consequences of appendicitis is described.

The association between appendicitis severity and patient age with appendiceal neoplasm histology-a population-based study

PURPOSE

Recent studies have reported alarming appendiceal tumor rates associated with complicated acute appendicitis, especially in patients presenting with a periappendicular abscess. However, the data on histology of appendiceal tumors among acute appendicitis patients is limited, especially in patient cohorts differentiating between uncomplicated and complicated acute appendicitis. We have previously reported the association of increased appendiceal tumor prevalence with complicated acute appendicitis in this population-based study. The objective of this secondary analysis was to evaluate the association of both appendicitis severity and patient age with appendiceal tumor histology.

METHODS

This nationwide population-based registry study (The Finnish Cancer Registry) was conducted from 2007 to 2013. All appendiceal tumors (n = 840) and available medical reports (n = 504) of these patients at eight study hospitals were previously evaluated, identifying altogether 250 patients with both acute appendicitis and appendiceal tumor.

RESULTS

The severity of acute appendicitis was significantly associated with more malignant tumor histology. The risk of adenocarcinoma or pseudomyxoma was significantly higher among patients with periappendicular abscess (OR 15.05, CI 95% 6.98-32.49, p < 0.001) and patients presenting with perforated acute appendicitis (OR 4.09, CI 95% 1.69-9.90, p = 0.0018) compared to patients with uncomplicated acute appendicitis. Similarly, patient age over 40 years was significantly associated with the risk of adenocarcinoma and pseudomyxoma (OR 26.46, Cl 95% 7.95-88.09, p < 0.001). Patient sex was not associated with a more malignant appendiceal tumor histology (p = 0.67).

CONCLUSION

More malignant appendiceal tumor histology of adenocarcinoma or pseudomyxoma was significantly associated with patient age over 40 years and complicated acute appendicitis, especially periappendicular abscess.

Prediction nomogram for evaluating the probability of postoperative fever in children with acute appendicitis

OBJECTIVE

The purpose of this study was to establish a predictive model of postoperative fever in children with acute appendicitis through retrospective analysis, and the prediction ability of the model is demonstrated by model evaluation and external validation.

METHODS

Medical records information on children undergoing surgery for acute appendicitis within 2 years were retrospectively collected, prospective collection was performed for external validation in the next 3 months. The patients were divided into two groups according to whether the postoperative body temperature exceeded 38.5°C. Multivariate logistic regression analysis was used to determine independent risk factors and develop regression equations and nomogram. ROC curve, calibration curve and decision curve were made for model evaluation. Finally, the clinical implication of the prediction model was clarified by associating postoperative fever with prognosis.

RESULTS

High risk factors of postoperative fever included in the prediction model were onset time (X1), preoperative temperature (X2), leukocyte count (X3), C-reactive protein (X4) and operation time (X5). The regression equation is logit (P) = 0.005X1+0.166X2+0.056X3+0.004X4+0.005X5-9.042. ROC curve showed that the area under the curve (AUC) of the training set was 0.660 (0.621, 0.699), and the AUC of the verification set was 0.712 (0.639, 0.784). The calibration curve suggested that the prediction probability was close to the actual probability. Decision curve analysis (DCA) showed that patients could benefit from clinician's judgment. Furthermore, prognostic analysis showed children presenting with postoperative fever had the more duration of postoperative fever, hospitalization stays and cost, except for rehospitalization.

CONCLUSION

All the results revealed that the model had good predictive ability. Pediatricians can calculate the probability of postoperative fever and make timely interventions to reduce pain for children and parents.

It's time to deconstruct treatment-failure: A randomized controlled trial of nonoperative management of uncomplicated pediatric appendicitis with antibiotics alone

BACKGROUND

Published data demonstrate that management of uncomplicated pediatric appendicitis with antibiotics-alone is safe and frequently successful. Randomized controlled trials (RCT) comparing antibiotics-alone to appendectomy are lacking, alongside insight into drivers of failure. We sought to validate the antibiotics-alone approach and identify barriers to success using an RCT design.

METHODS

Patients aged 6-17 years with uncomplicated appendicitis were randomized to appendectomy or intravenous piperacillin/tazobactam for 24-48 h followed by 10 days of oral ciprofloxacin/metronidazole. Enrollment required symptoms <48 h, WBC<18, appendiceal diameter <11 mm, and radiographic absence of perforation. Lack of clinical improvement or persistently elevated WBC resulted in appendectomy. Primary outcomes were 1-year success rate of antibiotics-alone and quality-of-life measures.

RESULTS

Among 39 children enrolled over 31 months, 20 were randomized to antibiotics-alone and 19 to surgery. At 1 year, 6 nonoperative patients underwent appendectomy (70% success). Four cases were not true antibiotic failures but instead reflected "pragmatic" challenges to executing nonoperative algorithms. Only 2 cases represented recurrent/refractory appendicitis, suggesting a 90% adjusted 1-year success rate. Parental PedsQL™ scores were similar between treatment cohorts (91.3 vs 90.2, P = 0.32). Children treated with antibiotics-alone had faster return to activity (2.0 vs 12 days, P = 0.001) and fewer parental missed work days (0.0 vs 2.5, P = 0.03).

CONCLUSIONS

These data corroborate findings from non-randomized studies suggesting 70-90% of uncomplicated pediatric appendicitis can be treated with antibiotics-alone, with fewer disability days. Failures appear multifactorial, often reflecting practical hurdles and not antibiotic limitations. As surgeons consider nonoperative protocols for uncomplicated appendicitis, these data further inform the variability of treatment success.

LEVEL OF EVIDENCE

1; randomized controlled trial.

OUP accepted manuscript

BACKGROUND

Non-operative management of uncomplicated acute appendicitis is an option, but omission of antibiotics from the regimen has not been tested.

METHODS

A double-blind, placebo-controlled, superiority RCT in adults with CT-confirmed uncomplicated acute appendicitis was designed to compare placebo with antibiotics (intravenous ertapenem followed by oral levofloxacin and metronidazole). The primary endpoint was treatment success (resolution resulting in discharge without appendicectomy within 10 days); secondary outcomes included pain scores, complications, hospital stay, and return to work.

RESULTS

From May 2017 to September 2020, 72 patients with a mean(s.d.) age of 37.5 (11.1) years were recruited at five hospitals. Six were excluded after randomization (5 early consent withdrawals, 1 randomization protocol violation), 35 were assigned to receive antibiotics, and 31 to receive placebo. Enrolment challenges (including hospital pharmacy resources in an acute-care surgery setting) meant that only the lowest sample size of three predefined scenarios was achieved. The 10-day treatment success rate was 87 (95 per cent c.i. 75 to 99) per cent for placebo and 97 (92 to 100) per cent for antibiotics. This clinical difference of 10 (90 per cent c.i. -0.9 to 21) per cent was not statistically different for the primary outcome (1-sided P = 0.142), and secondary outcomes were similar.

CONCLUSION

The lack of antibiotic superiority statistically suggests that a non-inferiority trial against placebo is warranted in adults with CT-confirmed mild appendicitis. Registration number: EudraCT 2015-003634-26 (https://eudract.ema.europa.eu/eudract-web/index.faces), NCT03234296 (http://www.clinicaltrials.gov).

Magnetic resonance imaging (MRI) for diagnosis of acute appendicitis

BACKGROUND

Appendicitis remains a difficult disease to diagnose, and imaging adjuncts are commonly employed. Magnetic resonance imaging (MRI) is an imaging test that can be used to diagnose appendicitis. It is not commonly regarded as a first-line imaging test for appendicitis, but the reported diagnostic accuracy in some studies is equivalent to computed tomography (CT) scans. As it does not expose patients to radiation, it is an attractive imaging modality, particularly in women and children.

OBJECTIVES

The primary objective was to determine the diagnostic accuracy of MRI for detecting appendicitis in all patients. Secondary objectives: To investigate the accuracy of MRI in subgroups of pregnant women, children, and adults. To investigate the potential influence of MRI scanning variables such as sequences, slice thickness, or field of view.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase until February 2021. We searched the references of included studies and other systematic reviews to identify further studies. We did not exclude studies that were unpublished, published in another language, or retrospective.

SELECTION CRITERIA

We included studies that compared the outcome of an MRI scan for suspected appendicitis with a reference standard of histology, intraoperative findings, or clinical follow-up. Three study team members independently filtered search results for eligible studies.

DATA COLLECTION AND ANALYSIS

We independently extracted study data and assessed study quality using the Quality Assessment of Studies of Diagnostic Accuracy - Revised (QUADAS-2) tool. We used the bivariate model to calculate pooled estimates of sensitivity and specificity.

MAIN RESULTS

We identified 58 studies with sufficient data for meta-analysis including a total of 7462 participants (1980 with and 5482 without acute appendicitis). Estimates of sensitivity ranged from 0.18 to 1.0; estimates of specificity ranged from 0.4 to 1.0. Summary sensitivity was 0.95 (95% confidence interval (CI) 0.94 to 0.97); summary specificity was 0.96 (95% CI 0.95 to 0.97). Sensitivity and specificity remained high on subgroup analysis for pregnant women (sensitivity 0.96 (95% CI 0.88 to 0.99); specificity 0.97 (95% CI 0.95 to 0.98); 21 studies, 2282 women); children (sensitivity 0.96 (95% CI 0.95 to 0.97); specificity 0.96 (95% CI 0.92 to 0.98); 17 studies, 2794 children); and adults (sensitivity 0.96 (95% CI 0.93 to 0.97); specificity 0.93 (95% CI 0.80 to 0.98); 9 studies, 1088 participants), as well as different scanning techniques. In a hypothetical cohort of 1000 patients, there would be 12 false-positive results and 30 false-negative results. Methodological quality of the included studies was poor, and the risk of bias was high or unclear in 53% to 83% of the QUADAS-2 domains.

AUTHORS' CONCLUSIONS

MRI appears to be highly accurate in confirming and excluding acute appendicitis in adults, children, and pregnant women regardless of protocol. The methodological quality of the included studies was generally low due to incomplete and low standards of follow-up, so summary estimates of sensitivity and specificity may be biased. We could not assess the impact and direction of potential bias given the very low number of high-quality studies. Studies comparing MRI protocols were few, and although we found no influence of MRI protocol variables on the summary estimates of accuracy, our results do not rule out that some MRI protocols are more accurate than others.

Antipseudomonal Versus Narrow-Spectrum Agents for the Treatment of Community-Onset Intra-abdominal Infections

Background

Antipseudomonal antibiotics are often used to treat community-acquired intra-abdominal infections (CA-IAIs) despite common causative pathogens being susceptible to more narrow-spectrum agents. The purpose of this study was to compare treatment-associated complications in adult patients treated for CA-IAI with antipseudomonal versus narrow-spectrum regimens.

Methods

This retrospective cohort study included patients >18 years admitted for CA-IAI treated with antibiotics. The primary objective of this study was to compare 90-day treatment-associated complications between patients treated empirically with antipseudomonal versus narrow-spectrum regimens. Secondary objectives were to compare infection and treatment characteristics along with patient outcomes. Subgroup analyses were planned to compare outcomes of patients with low-risk and high-risk CA-IAIs and patients requiring surgical intervention versus medically managed.

Results

A total of 350 patients were included: antipseudomonal, n=204; narrow spectrum, n=146. There were no differences in 90-day treatment-associated complications between groups (antipseudomonal 15.1% vs narrow spectrum 11.3%, P=.296). In addition, no differences were observed in hospital length of stay, 90-day readmission, Clostridiodes difficile, or mortality. In multivariate logistic regression, treatment with a narrow-spectrum regimen (odds ratio [OR], 0.75; 95% confidence interval, 0.39–1.45) was not independently associated with the primary outcome. No differences were observed in 90-day treatment-associated complications for (1) patients with low-risk (antipseudomonal 15% vs narrow spectrum 9.6%, P=.154) or high-risk CA-IAI (antipseudomonal 15.8% vs narrow spectrum 22.2%, P=.588) or (2) those who were surgically (antipseudomonal 8.5% vs narrow spectrum 9.2%, P=.877) or medically managed (antipseudomonal 23.1 vs narrow spectrum 14.5, P=.178).

Conclusions

Treatment-associated complications were similar among patients treated with antipseudomonal and narrow-spectrum antibiotics. Antipseudomonal therapy is likely unnecessary for most patients with CA-IAI.

Immunohistochemical Inflammation in Histologically Normal Appendices in Patients with Right Iliac Fossa Pain

BACKGROUND

Histologically normal appendices resected for right iliac fossa pain in children demonstrate immunohistochemical markers of inflammation. We aimed to establish if subclinical inflammation was present in histologically normal appendices resected from adults with right iliac fossa pain.

METHODS

Immunohistochemistry was performed on formalin-fixed paraffin-embedded appendices for tumour necrosis factor (TNF)-α, interleukin (IL)-6, IL-2R and serotonin in four groups: Group I (n = 120): uncomplicated appendicitis, Group II (n = 118): complicated appendicitis (perforation or gangrene), Group III (n = 104): histologically normal appendices resected for right iliac fossa pain and Group IV (n = 106) appendices resected at elective colectomy. Expression was quantified using the H-scoring system.

RESULTS

Median, interquartile range expression of TNF-α was increased in Groups I (5.9, 3.1-9.8), II (6.8, 3.6-12.1) and III (9.8, 6.2-15.2) when compared with Group IV (3.0, 1.4-4.7, p < 0.01). Epithelial expression of IL-6 in Groups II (44.0, 8.0-97.0) and III (71.0, 18.5-130.0) was increased when compared with Group IV (9.5, 1.0-60.2, p < 0.01). Expression of mucosal IL-2R in Groups I (47.4, 34.8-69.0), II (37.8, 25.4-60.4) and III (18.4, 10.1-34.7) was increased when compared with Group IV (2.8, 1.2-5.7, p < 0.01). Serotonin content in Groups I (3.0, 0-30.0) and II (0, 0-8.5) was decreased when compared with Groups III (49.7, 16.7-107.5) and IV (43.5, 9.5-115.8, p < 0.01).

CONCLUSION

Histologically normal appendices resected from symptomatic patients exhibited increased proinflammatory cytokine expression on immunohistochemistry suggesting the presence of an inflammatory process not detected on conventional microscopy.