Risk factors for intra-abdominal abscess post laparoscopic appendicectomy for gangrenous or perforated appendicitis: A retrospective cohort study

Risk factors for developing intra-abdominal abscess following appendicectomy for acute appendicitis: a retrospective cohort study

BACKGROUND

Laparoscopic appendicectomy is commonly performed in Australia for treatment of acute appendicitis. Intra-abdominal abscess (IAA) is a potential complication following appendicectomy for acute appendicitis. Risk factors for developing post-operative IAA remain controversial and poorly defined. Laparoscopic washout may be performed for patients who develop complication(s) including IAA. The aim of this study was to define risk factors for both the development of IAA and identify patients who may require laparoscopic washout following appendicectomy.

METHODS

Data were obtained from 423 patients who underwent laparoscopic appendicectomy over a five-year period (2012-2017). Clinical (fever, haemodynamics, examination findings), biochemical (white cell count, neutrophil count, C-reactive protein, bilirubin, albumin), radiological (CT free fluid), and operative factors (inflammation, suppuration, free-fluid, perforation, histopathology) collected in the pre-, peri-, and post-operative period(s) were analysed.

RESULTS

23 (5.4%) patients developed post-operative IAA. Duration of intravenous antibiotics was significantly longer in patients who developed IAA and in those who required laparoscopic washout (p < 0.0001). C-reactive protein (CRP) on admission (p < 0.05) and appendiceal perforation (p = 0.0005) were significantly higher in patients who either developed IAA or needed laparoscopic washout. No clinical or radiological finding predicted either the development of IAA or need for laparoscopic washout.

CONCLUSION

Elevated CRP on admission may predict the development of post-operative IAA formation or the need for laparoscopic washout post-appendicectomy. Prolonged post-operative antibiotic use appears independent of the development of IAA as well as the need for laparoscopic washout. These data highlight the need for clear guidelines on peri-operative antibiotic use following appendicectomy.

Varying negative appendectomy rates after laparoscopic appendectomy: a systematic review and meta-analysis

PURPOSE

Appendicitis is a common cause of acute abdominal pain, and treatment with laparoscopy has become increasingly common during the past two decades. Guidelines recommend that normal appendices are removed if operated for suspected acute appendicitis. It is unclear how many patients are affected by this recommendation. The aim of this study was to estimate the rate of negative appendectomies in patients undergoing laparoscopic surgery for suspected acute appendicitis.

METHODS

This study was reported following the PRISMA 2020 statement. A systematic search was conducted in PubMed and Embase for retrospective or prospective cohort studies (with n ≥ 100) including patients with suspected acute appendicitis. The primary outcome was the histopathologically confirmed negative appendectomy rate after a laparoscopic approach with a 95% confidence interval (CI). We performed subgroup analyses on geographical region, age, sex, and use of preoperative imaging or scoring systems. The risk of bias was assessed using the Newcastle-Ottawa Scale. Certainty of the evidence was assessed using GRADE.

RESULTS

In total, 74 studies were identified, summing up to 76,688 patients. The negative appendectomy rate varied from 0% to 46% in the included studies (interquartile range 4-20%). The meta-analysis estimated the negative appendectomy rate to be 13% (95% CI 12-14%) with large variations between the individual studies. Sensitivity analyses did not change the estimate. The certainty of evidence by GRADE was moderate due to inconsistency in point estimates.

CONCLUSION

The overall estimated negative appendectomy rate after laparoscopic surgery was 13% with moderate certainty of evidence. The negative appendectomy rate varied greatly between studies.

Are Preoperative CT Findings Useful for Predicting Postoperative Intraabdominal Abscess in the Patients with Acute Appendicitis?

Background and objective: In patients with acute appendicitis (AA), preoperative computed tomography (CT) findings suggesting development of intraabdominal abscess (IAA) had not been widely used. The aim of this study was to investigate the preoperative clinical and radiological factors that predict the development of a postoperative IAA in patients with AA who were treated by laparoscopic appendectomy (LA). Methods: Two hundred and sixteen patients with pathologically proven AA underwent LA between January 2013 and March 2018 in our department. Medical records and preoperative CT images of these 216 patients were retrospectively reviewed and the predictive factors of postoperative IAA were investigated. In addition, patients were divided into complicated appendicitis (CA) and simple appendicitis (SA) and perioperative factors of two groups were compared. Results: One hundred and forty-seven patients were diagnosed with CA, while the other 69 patients were diagnosed with SA. Sixteen patients developed postoperative IAA in the CA group, while no patients in the SA group did. The univariate analysis revealed that time from onset to surgery more than 3 days (p = 0.011), the preoperative CT finding of periappendiceal fluid (p = 0.003), abscess (p < 0.001), and free air (p < 0.001), operation time more than 120 min (p = 0.023) and placement of a drainage tube (p < 0.001) were significantly associated with the development of IAA. Multivariate analysis revealed that the preoperative CT finding of free air was independently associated with the development of IAA (p = 0.007, odds ratio = 5.427, 95% CI: 1.586⁻18.57). Conclusions: IAA developed predominantly in patients with CA. Preoperative CT findings of free air was found to be an independent predictor for the development of IAA. Surgeons should be meticulous in managing the postoperative course of patients with this finding.

Post-appendectomy pelvic abscess with extended-spectrum beta-lactamase producing Escherichia coli: A case report and review of literature

BACKGROUND

Appendicitis, the inflammation of the appendix, is the most common abdominal surgical emergency requiring expedient surgical intervention. Extended-spectrum beta-lactamases (ESBLs) are bacterial enzymes that catalyse the degradation of the beta-lactam ring of penicillins and cephalosporins (but without carbapenemase activity), leading to resistance of these bacteria to beta-lactam antibiotics. Recent increases in incidence of ESBL-producing bacteria have caused alarm worldwide. Proportion estimates of ESBL-Enterobacteriaceae hover around 46% in China, 42% in East Africa, 12% in Germany, and 8% in the United States.

CASE SUMMARY

The impact of ESBL-producing bacteria on appendiceal abscesses and consequent pelvic abscesses are yet to be examined in depth. A literature review using the search words “appendiceal abscesses” and “ESBL Escherichia coli (E. coli)” revealed very few cases involving ESBL E. coli in any capacity in the context of appendiceal abscesses. This report describes the clinical aspects of a patient with appendicitis who developed a postoperative pelvic abscess infected with ESBL-producing E. coli. In this report, we discuss the risk factors for contracting ESBL E. coli infection in appendicitis and post-appendectomy pelvis abscesses. We also discuss our management approach for post-appendectomy ESBL E. coli pelvic abscesses, including drainage, pathogen identification, and pathogen characterisation. When ESBL E. coli is confirmed, carbapenem antibiotics should be promptly administered, as was done efficaciously with this patient. Our report is the first one in a developed country involving ESBL E. coli related surgical complications in association with a routine laparoscopic appendectomy.

CONCLUSION

Our report is the first involving ESBL E. coli and appendiceal abscesses, and that too consequent to laparoscopic appendectomy.