Optimizing Clinical Outcomes of Acute Appendicitis  

Cecilia Munguti, Stanley Mugambi, Abdulkarim Abdallah

1Department of Surgery, Aga Khan University Hospital, Nairobi, Kenya

Correspondence to:  Cecilia Munguti; email: cecmunguti@gmail.com

Received: 17 Aug 2021; Revised: 5 Apr 2022; Accepted: 12 Apr 2022; Available online: 4 May 2022

Abstract

Background: Appendectomy is a common emergency procedure in general surgery. The objective of this study was to identify factors that impact on outcomes following appendectomy for acute appendicitis. Methodology: A chart review of all patients with a diagnosis of acute appendicitis who underwent appendectomy at Aga Khan University Hospital between January 2018 and December 2019 was performed. Results: Most of the patients (male-to-female ratio, 2:1; mean age, 35±15.6 years) presented with acute uncomplicated appendicitis within an average of 2.98 days from symptom onset. The most common clinical sign was right lower quadrant tenderness. Abdominal ultrasound had a low sensitivity (33%), but computed tomography of the abdomen, which is the preferred imaging modality, had a high sensitivity (93%). The overall complication rate was 10.9%, with no statistically significant difference between open and laparoscopic appendectomy in terms of duration of surgery, length of hospital stay, and complication rates. The negative appendectomy rate was 6%. Conclusion: The complication rates of acute appendicitis in this setting are within international rates, but the negative appendectomy rate remains high. A more accurate interpretation of available imaging modalities is needed to improve this rate.

 

Keywords: Acute appendicitis, Appendectomy, Patient outcomes.

 

Ann Afr Surg. 2022; 19(3): 137-143

DOI: http://dx.doi.org/10.4314/aas.v19i3.2

Funding: None

© 2022 Author. This work is licensed under the Creative Commons Attribution 4.0 International License.

Introduction

Acute appendicitis is the most common abdominal surgical emergency worldwide, with a lifetime risk of 7%-19% and a mortality rate of 0.3%-1.7%. The incidence is higher in males than in females, with a peak between ages of 10 and 19 years (1).

The diagnosis of acute appendicitis remains a challenge due to variability in clinical presentation (2). On the one hand, missed or delayed diagnosis of acute appendicitis may lead to poor clinical outcome, and on the other hand, a negative appendectomy has been shown to increase patient morbidity, increase risk for adhesive small bowel obstruction, and increase overall healthcare costs(3). Diagnosis based on clinical presentation alone has pitfalls and has been associated with a negative appendectomy rate of up to 20% (4).

Numerous scoring systems have been formulated to assist clinicians in diagnosing acute appendicitis accurately, albeit with varied sensitivity and specificity, and the Modified Alvarado score is the most commonly used (5, 6). Ultrasound imaging has been proposed as a first-line imaging for patients with a low Alvarado score, but even in such scenarios, ultrasound has been found to be extremely user-dependent and with variably low sensitivity and specificity (7). With the need for more accurate diagnostic modalities, the use of abdominal computed tomography (CT) scan has been investigated, and studies show a reduction in the negative appendectomy rate to 2% (8).

This is a single-center case series description of demographics, clinical presentation, visual grade, surgical approach, and negative appendectomy rate and a comparison of diagnostic data, management, and outcomes, including the negative appendectomy rate in patients presenting with acute appendicitis over a period of 2 years in a teaching and referral hospital.

Methodology

Ethics statement

Ethical approval was obtained from the ethics and research committee of Aga Khan University Hospital.

 

Study population

This study included all patients diagnosed with acute appendicitis on histology and imaging at Aga Khan University Hospital, a single tertiary facility, between January 2018 and December 2019.

 

Data acquisition

A chart review of all patients with a diagnosis of acute appendicitis on histology and imaging was done. Information retrieved included patient age, sex, symptoms and signs, duration of illness, presence of leukocytosis, diagnostic workup, duration to surgery, duration of surgery, surgical approach, and outcomes (length of hospital stay, negative appendectomy rate, and complications).

 

Operational definition and terms

Symptoms were grouped into peritoneal (abdominal pain, localized or migratory), gastrointestinal (anorexia, nausea, and vomiting), and change in bowel habit (diarrhea or constipation).

The disease severity scoring grading for acute appendicitis was used for visual assessment: grade 1, inflamed; grade 2, gangrenous; grade 3, perforated with free localized fluid; grade 4, perforated with a regional abscess; grade 5, perforated with diffuse peritonitis (9).

Radiological descriptive terms used to infer acute appendicitis in this series were dilated, enlarged, or thickened appendix and fat stranding. The CT scan grades based on the radiologist’s description of the images were the following: grade 0, normal appendix; grade 1, early uncomplicated with dilatation or fat-stranding; grade 2, local complication with phlegmon or peri-appendiceal fluid; grade 3, regional complication with peritoneal or pelvic fluid or free peritoneal gas.

Histological grades were translated from the pathologist’s description of the specimen on microscopy: grade 0, normal appendix (no congestion or mucosal inflammation or ulceration); grade 1, early uncomplicated (mucosal or transmural inflammation); grade 2, local complication (partial necrosis, no perforation); grade 3, complicated (perforated and/or gangrenous).

 

Statistical analysis

Descriptive statistics were used to analyze the patients’ characteristics, clinical symptomatology, and diagnostic and management approaches. The sensitivity and specificity of laboratory investigations and imaging modalities were calculated using the histopathology diagnosis of acute appendicitis as the gold standard. Multivariate analysis was used to determine associations between the management modalities and outcomes.

 

Results

Patient characteristics

The records of 180 patients with a diagnosis of acute appendicitis were identified. Of 180 patients, 173 underwent surgery, 4 were managed medically with no surgery for an appendicular phlegmon, and 3 wer