Clinical and histopathological analysis of the patients undergoing appendectomy

Copyright: This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Background: Acute appendicitis is one of the most common surgical emergencies, but the diagnosis is difficult even with the sophisticated diagnostic tools. The aim of this study is to analyze the clinical and histopathological features of acute appendicitis and to see how reliable the clinical scoring system modified Alvarado score in our setup.


INTRODUCTION
Acute appendicitis is one of the most common diseases encountered in emergency.This disease needs emergent surgical intervention. 1The diagnosis is made pre-operatively with certain scoring systems and the decision of emergency appendectomy is taken on the basis of these scores. 2hough the sophisticated investigatory investigations are being evolving, they are not able to confirm the diagnosis all the time.In our setup, due to financial constraint, most of our patients cannot afford expensive investigations so we depend only on the scoring systems.We use modified Alvarado scoring (MAS) system to make the diagnosis of acute appendicitis.The parameters of this scoring system can be remembered with the pneumonic MANTREL (migrating pain, anorexia, nausea or vomiting, tenderness, rebound tenderness, elevated temperature and leucocytosis).The modified Alvarado scoring system has been shown to be easy, simple and cheap diagnostic tool for supporting the diagnosis of acute appendicitis. 3In this study, we wanted to see how reliable was the clinical scoring system i.e.modified Alvarado scoring and also its correlation with the different types of histopathological findings.

MATERIALS AND METHODS
This was a retrospective observational study conducted at KIST Medical College and Teaching Hospital.A capital from the institutional review committee was obtained.The medical records of the patients who underwent appendectomy either by open or laparoscopic method during two years (july1, 2016 to jun30, 2018) were searched.The Patients who had no complete information in the medical records were excluded from the study.118 patients fulfilling the inclusion criteria were included in the study.The clinical characteristics of the patients in terms of modified Alvarado Score were outlined.The modified Alvarado Scoring system included three symptoms (migration of pain to the right iliac fossa, anorexia and nausea or vomiting), three physical signs (tenderness, rebound tenderness and elevation of temperature) and one laboratory finding (leukocytosis).(Table 1) The strength of the parameters were different as shown in Table 1.Final score was obtained after adding all parameters.The diagnosis of acute appendicitis was confirmed by histopathological examination.The different histopathological findings of the appendix were obtained from pathological department.

Statistical analysis
All the observed data of the clinical characteristics of the patients and the histopathological findings of appendix were tabulated in MS-Excel and statistically analyzed using SPSS statistics software, version 21.

RESULTS
In our study of 118 (69 males and 49 females) patients with M:F ratio of 1.41:1, the highest number of patients (66.96%) were observed in the age group of 19 to 40 and the least number of patients (3.39%) were observed in the age group of 61 years and above (table 2, 3).The mean age of patients in our study was 27.46±12.724years (male 26.41±12.651years and female 28.94±12.809years).
We divided the modified Alvarado scores into three categories as unlikely (MAS 1-3), less likely (MAS 4-6) and more likely (MAS 7-9) groups.The modified Alvarado score of <4 was observed in 18 patients, 4-6 in 44 patients, 7-9 in 56 patients (table 4).In our study, 56 patients (clinical positive) were in the more likely appendicitis (MAS 7-9) group, 62 patients (clinical negative) were in less likely or unlikely groups (MAS 6 or less).After histopathological examination, 52 patients (true positive) out of 56 had acute appendicitis and 4 patients (false positive) had noninflammed appendices.Seven patients (true negative) out of 62 had acute appendicitis and 55 patients (false negative) had non-inflamed appendices.(table 5)

DISCUSSION
Acute appendicitis is one of the most common surgical emergencies.The highest incidence is in the age group of 15-24 years. 4There is an approximately 8% estimated life time prevalence of acute appendicitis with peak incidence in the age group 10-30 years. 5In our study, the highest incidence of acute appendicitis was observed in 19-40 years and the lowest incidence in 61 years or above (table 2).In our study of 118 (69 males and 49 females) patients (table 3), male to female ratio was 1.41:1, which was higher in contrast to other studies. 6,7f appendectomy is delayed, there are high chances of complications like appendicular perforation and sepsis with high mortality 8 and in contrast with reduced diagnostic accuracy, rate of negative appendectomy increases which is generally reported to be approximately (20-40%). 9The morbidity and mortality of omitting the surgery for acute appendicitis are sometimes far severe than performing a certain percentage of negative appendicectomy.Our rate of negative appendicectomy was 9.32%, lower than the rate mentioned in the literature. 9This may be due to the involvement of more male patients in our study because diagnosing acute appendicitis in the female patients is more challenging.Females always have more negative appendectomy than males because of gynecological conditions mimicking appendicitis. 6,7,10,11Now sophisticated diagnostic modalities like CT scan, MRI etc. are also available and the diagnostic accuracy can be improved.But most of the people in our region cannot afford these costly modalities.At present, various scoring systems are available to improve diagnostic accuracy.Alvarado and modified Alvarado scores are most popular with reported sensitivity and specificity of both are 53 to 88% and 75 to 80%, respectively. 9,12In our study, the sensitivity of the modified Alvarado scores was 48.60%, specificity 63.64%, positive predictive value 92.86%, and negative predictive value 11.29% with diagnostic accuracyof 47.46%.
Whenever we correlated the MAS with the histopathological examinations of the resected appendiceal specimen (table 4), we found that negative appendectomy rate was the lowest (7.14%) in the more likely group.However, the negative appendectomy rates were more or less similar (11.11% vs 11.36%) among the unlikely and less likely groups respectively.Thus the MAS can be used to diagnose acute appendicitis in the emergency setting.
As shown in the table 5, the intraoperative findings are not seen to be consistent with histopathological findings.Out of 78 cases diagnosed intraoperatively as acute appendicitis, 8 cases showed no appendiceal inflammation.Out of 12 cases of intraoperative gangrenous appendicitis, only 8 cases turned to be so after HPE.Out of 24 appendicular lump cases, 2 appendices were normal in HPE.So we should send all types of appendiceal specimen for histopathological examination to come to the final accurate diagnosis.
There were some limitations in our study.The sample size of this study was small to validate this scoring system and our study was conducted in a single private medical college within a certain period of time Nowadays, other scoring systems are also available.RIPASA being one of such scoring system studied.RIPASA scoring system is shown to be superior to the modified Alvarado scoring in terms of sensitivity, specificity and negative appendectomy rate. 4However another recent study showed no advantages of RIPASA scoring system over the modified Alvarado score when applied to the patients presenting with suspected acute appendicitis. 13In a recently published study 14 , comparison among the seven scoring systems namely the Alvarado score (AS), modified Alvarado score (MAS), Fenyo-Lindberg score (FS), Lintula score (LS), Eskelinen score (ES), Teicher score (TS), and Christian score (CS) was done and concluded that FS, LS, and TS had a lower diagnostic sensitivity in women; and FS, ES, TS, and CS had a low sensitivity in patients with a duration of illness greater than 48 hours.Ohmann and Eskelinen scores were found superior to modified Alvarado score in another study. 15 future, we should involve a large number of patients in a prospective study to compare the diagnostic accuracy of multiple scoring systems in our setup.Multi centric data can be utilized.
Koirala K et al.

Table 1 : Features of Modified Alvarado Score Examination/Test Score Migratory pain from epigastric region to right lower quadrant 1
DOI : 10.3126/jpn.v8i2.20862