The research conundrum of 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 (3) Results: The assumption that appendicitis invariably will proceed to perforation has been outdated.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.

Geographic Association Between Incidence of Acute Appendicitis and Socioeconomic Status

Importance

Some studies based on proportions of patients with perforated appendicitis (PA) among all patients with acute appendicitis (AA) have found an association between socioeconomic status (SES) and risk of perforation. A potential limitation is their use of proportions, which assumes that incidence of AA is evenly distributed across populations at risk. This assumption may be invalid, and SES may have a more complex association with both AA and PA.

Objective

To generate population-based incidences of AA and PA and to examine geographic patterns of incidence alongside geographic patterns of SES.

Design, Setting, and Participants

Retrospective study of data from Washington's Comprehensive Hospital Abstract Reporting System and the 2010 US census. Geographic methods were used to identify patterns of age- and sex-standardized incidence in Washington State between 2008 and 2012. The study included all patients discharged with International Classification of Diseases, Ninth Revision codes for AA or PA. Data were analyzed between November 2016 and December 2018.

Exposures

Location of primary residence.

Main Outcomes and Measures

Age- and sex-standardized incidence for AA and PA was generated for each census tract (CT). Global spatial autocorrelation was examined using Moran index (0.0 = completely random incidence; 1.0 = fully dependent on location). Clusters of low-incidence CTs (cold spots) and high-incidence CTs (hot spots) were identified for AA. Census-based SES data were aggregated for hot spots and cold spots and then compared.

Results

Statewide, over the 5-year study period, there were 35 730 patients with AA (including 9780 cases of PA), of whom 16 574 were women (46.4%). Median age of the cohort was 29 years (IQR, 16-48 years). Statewide incidence of AA and PA was 106 and 29 per 100 000 person-years (PY), respectively. Crude incidence was higher within the male population and peaked at age 10 to 19 years. Age- and sex-standardized incidence of AA demonstrated significant positive spatial autocorrelation (Moran index, 0.30; P < .001), but autocorrelation for PA was only half as strong (0.16; P < .001). Median incidence of AA was 118.1 per 100 000 PY among hot spots vs 86.2 per 100 000 PY among cold spots (P < .001). Socioeconomic status was higher in cold spots vs hot spots: mean proportion of college-educated adults was 56% vs 26% (P < .001), and mean per capita income was $44 691 vs $30 027 (P < .001).

Conclusions and Relevance

Age- and sex-standardized incidence of appendicitis is not randomly distributed across geographic subunits, and geographic clustering of AA is twice as strong as PA. Socioeconomic advantages, such as higher income and secondary education, are strongly associated with lower incidence of AA. These findings challenge conventional views that AA occurs randomly and has no predisposing characteristics beyond age/sex. Socioeconomic status, and likely other geographically circumscribed factors, are associated with incidence of AA.

Appendiceal Duplication: A Comprehensive Review of Published Cases and Clinical Recommendations

BACKGROUND

Duplex appendix is very rare (incidence 0.004%) but has clinical relevance given the frequency of appendicectomies performed. Failure to recognise duplication can result in failure of treatment and medico-legal consequences. A review of published cases was undertaken to identify factors that may help in managing this rare condition.

METHODS

All English and non-English publications were identified in PubMed, Embase and Cochrane databases. Patient demographics, intraoperative findings, anatomical details and histopathology were analysed.

RESULTS

A total of 141 cases were identified [male/female ratio 1.4:1, median age 20 years (range foetus to 69 years)]. Duplication of the appendix ranges from branching of the appendix trunk to a fully matured appendix located elsewhere along the colon. Most can be categorised by the Cave-Wallbridge classification. There were 22 Type A, 8 Type B1, 46 Type B2 and 10 Type C cases (Cave-Wallbridge). There were six cases of horseshoe and two cases of triple appendix. Six reports gave anatomical descriptions that could not be classified by Cave-Wallbridge categories and in 11 cases there were no anatomical descriptions.

CONCLUSIONS

An anteriorly placed appendix, away from the convergence of the taenia, or a normal appendix in the presence of convincing clinical or radiological signs of appendicitis should instigate a careful examination of the caecal pole and possible exploration of the retrocaecal space for appendiceal duplication. If the patient had previous surgery for congenital abnormalities, Type B1 or Type C duplication should be considered.

Non-operative management of appendicitis in children

While appendicectomy has been considered the mainstay of treatment for children with acute appendicitis for many decades, there has been a great deal of recent interest in non-operative treatment (NOT) with antibiotics alone. Initial results suggest that many children with appendicitis can indeed be safely treated with NOT and can be spared the surgeon's knife. Many as yet unanswered questions remain, however, before NOT can be considered a realistic and reliable alternative to surgery. This review summaries current knowledge and understanding of the role of NOT in children with appendicitis and outlines and discusses the outstanding knowledge gaps.

A bibliometric analysis of the citation classics of acute appendicitis

INTRODUCTION

Acute appendicitis is one of the most commonly encountered emergency surgical conditions. An understanding of the most highly cited research works in this field is key to good evidence based clinical practice.

AIMS

To perform a bibliometric analysis on the 100 most frequently cited articles in the field of acute appendicitis.

METHODS

The database of the Institute for Scientific Information (ISI) Web of Science Expanded citation index was searched to identify the 100 most frequently cited articles in the field of acute appendicitis. The web of science expanded citation index tracks article citations made since 1946.

RESULTS

The top 100 most frequently cited articles were selected for analysis in this series. The most frequently cited article was cited 649 times and the least cited three article 93 times. The average number of citations per article was 167.74. The top 100 cited articles originated from 17 countries. Over half of the papers originated from the USA. Fifty-one of the papers concentrated on diagnostics of acute appendicitis. Thirty-six papers looked at the treatment of acute appendicitis with 30 of these dealing with the surgical management of the disease. There were 6 studies at level 1a, 20 studies at level 1b and 43,5,17 and 9 studies at levels 2, 3, 4 and 5 respectively.

CONCLUSIONS

Bibliometric analysis of the citation classics in a given field can provide interesting insights into the relationship between the quality of research outputs and clinical practice. The study of acute appendicitis remains an active field of research with a growing body of higher quality evidence underpinning our clinical practice.

WSES Jerusalem guidelines for diagnosis and treatment of acute appendicitis

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