RIPASA versus Alvarado score in the assessment of acute appendicitis: A prospective study

Abstract

Objective: This study aimed to compare Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) and Alvarado scoring to accurately identify acute appendicitis.

Material and Methods: A cross-sectional prospective study was carried out in the department of surgery. Patients were enrolled and scored using RIPASA and Alvarado scoring systems. Appendectomy was done, and the specimen was sent for histopathology examination, which was used as the gold standard for diagnosis. Among 400 recruits, 11 patients were lost to follow-up, giving us a sample size of 389 patients. The cut-off value for RIPASA and Alvarado scores was 7.5 and 7.0, respectively. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy in diagnosing acute appendicitis of both scores were analyzed using SPSS.

Results: Among 389 patients, 256 (66%) were males, and 277 (71%) were under the age of 40 years. RIPASA was more than 7.5 in 345 cases, while Alvarado was more than 7.0 in 261 patients. RIPASA score had a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 95.8%, 87.9%, 98.9%, and 65.9%, respectively. In contrast, the ALVARADO score was 71.1% sensitive and 75.8% specific. RIPASA had a diagnostic accuracy of 95.12%, while Alvarado was only 71.46% accurate in diagnosing acute appendicitis.

Conclusion: Compared to the Alvarado scoring system, RIPASA is a better tool in terms of accuracy, sensitivity, and specificity for diagnosing acute appendicitis.

Keywords: Appendicitis, diagnostic technique, RIPASA score, Alvarado score, diagnostic accuracy

Introduction

Acute appendicitis is the most common surgical emergency presenting to hospitals, with a lifetime prevalence of roughly 7% (1). In males, the incidence of acute appendicitis is higher compared to women (2). Several acute abdominal pathologies tend to mimic acute appendicitis’ clinical symptomatology. However, appendectomy remains the gold-standard management for acute appendicitis (3). Even though appendicitis is a common problem that hospital patients come in with, diagnosis is still difficult and primarily clinical, with some laboratory findings, such as raised white blood cells (WBC) count, offering some assistance (4).

Grading systems have historically been used to aid physicians in making a more precise diagnosis and preventing unnecessary appendectomies due to the wide variety of reasons for right iliac fossa pain and clinical presentations for appendicitis. In the recent past, imaging modalities such as CT scans have helped with diagnostic challenges (5). In contexts where ordering frequent CT scans would result in extra resources and cost restrictions, clinical scoring criteria are nevertheless regarded as essential diagnostic auxiliary tools (6). The most prominent scoring system in this regard historically has been the Alvarado score, followed by the modified Alvarado score. These scoring systems were developed in the West, but when they were applied to other populations, particularly those in Asia, they did not show the same sensitivity and specificity (7,8). In order to stratify the risk of acute appendicitis among Asians, the Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) score system, developed in Brunei Darussalam in 2008, has proven to be beneficial (9). The parameters that make up the RIPASA grading system sum into a total score of 17.5 (9). This grading system requires just two routine investigations (WBC count and urine R/E) that are easily reported, yielding results that have a high negative predictive value that could reduce hospital costs by preventing negative appendectomy rates (10).

Some centres still utilize the Alvarado score to determine the likelihood of acute appendicitis despite the mounting evidence in favour of RIPASA. Owing to its decreased sensitivity and specificity, there is still a chance of making an inaccurate diagnosis and receiving subpar treatment. Untreated appendicitis can result in worse outcomes such as perforation, peritonitis, or abscess formation (11). Therefore, our study aims to compare the two scoring systems, RIPASA and Alvarado, to accurately identify acute appendicitis in our population.

Material and Methods

A cross-sectional prospective study was carried out at the department of surgery spanning over a time course of one year from January 2022 to December 2022. Approval was obtained from the ethical review board of the institute (Date: 16.12.2021), and informed consent was taken from all the participants. The study included all individuals who were clinically suspected to have acute appendicitis with the aid of an ultrasonography examination. The study eliminated participants who were under the age of 15, pregnant, had an appendicular mass, or had peritonitis-like symptoms. All patients who met the study eligibility requirements underwent RIPASA and Alvarado scoring by the same surgical team. Tables 1 and 2 describe the detailed parameters of the Alvarado and RIPASA grading system. The Alvarado score threshold was set at 7, while the RIPASA score cut-off was set at 7.5, and the scores were deemed positive when they were over 7 and 7.5, respectively. The appendectomies performed on the recruited patients were followed by specimens being sent for histopathology. Upon their discharge, patients were monitored for any postoperative problems and then had a follow-up assessment one week later. After that, histopathology results were recorded to distinguish between positive and negative appendectomies, and the outcomes were then associated with both scores.

Table 1. Alvarado grading system

Table 2. RIPASA grading system

Statistical Analysis

The data was entered and analysed using Statistical Package for Social Sciences (SPSS) version 23. Frequency and percentages were calculated for age, gender, duration of symptoms, histopathology, RIPASA and the Alvarado scores. The chi-square test was used to compare categorical variables, and the results were tabulated. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of both the scores were calculated. A p-value of 0.05 or lower was deemed significant.

Results

During the course of the study, 400 patients between the ages of 15 and 65 were enrolled in the study out of which 11 were lost to follow-up, leaving 389 patients for final evaluation. Of the recruited population, 71.2% (n= 277) were younger than 40 years, while 28.8% (n= 112) were older than 40 years. Out of 389 patients, 65.8% (n= 256) were males while 34.2% (n= 133) were females. Of patients, 75.8% (n= 295) had a duration of symptoms of less than 48 hours, while 24.2% (n= 94) had symptoms that lasted more than 48 hours. Out of 389 subjects, 345 (88.7%) had RIPASA scores greater than 7.5, while 261 (67.1%) cases had Alvarado scores greater than 7, as shown in Table 3. The participant’s peroperative findings are shown in Figure 1.

Table 3. Characteristics of the study participants

Figure 1. Per-operative findings of appendectomy.

Of the 345 patients with RIPASA >7.5, 341 had appendicitis on the histopathology report and four patients had histopathology reporting negative for appendicitis. A RIPASA score of less than 7.5 was seen in 44 (11.3%) individuals, of whom 15 had positive histopathology results and 29 had negative histopathology reports. Out of 261 patients, 253 cases were histopathology-proven positive with an Alvarado score >7.0, whereas it was less than 7.0 in 128 patients, 103 of whom tested positively and 25 were negative on histopathology results, shown in Tables 4 and 5.

Table 4. Diagnostic value of RIPASA scoring system

Table 5. Diagnostic value of Alvarado scoring system

The RIPASA score was 95.8% sensitive and 87.9% specific in diagnosing acute appendicitis with a positive predictive value (PPV) and a negative predictive value (NPV) of 98.9% and 65.9%, respectively. The sensitivity, specificity, PPV, and NPV of the Alvarado score were 71.1%, 75.8%, 96.9%, and 19.5%, respectively. The diagnostic accuracy of the RIPASA and Alvarado scoring systems was 95.12% and 71.46%, respectively as shown in Tables 4 and 5.

Discussion

Across the world, acute appendicitis is a common condition with which patients present to the hospital, especially individuals under the age of 40 years. Appendectomy is a common procedure carried out in emergency services accounting for approximately 10% of the surgical procedures carried out for abdominal pathology (12-14). The most crucial factor in a surgeon’s clinical evaluation is seen to be the ability to diagnose acute appendicitis. Appendectomy rates of 15-30% come from basing one’s choice to operate only on a clinical approach (15,16). Despite the high levels of sensitivity and specificity that contrast-enhanced computed tomography (CECT) scans may attain, it is not always feasible to expose all individuals who may have acute appendicitis to CECT, especially in underdeveloped nations (17).

In this context, a variety of scoring systems have been created, with RIPASA and Alvarado being the most widely utilized. This study compared the two scoring methods among Asian people to identify a superior score with higher diagnostic accuracy. In our investigation, the RIPASA score sensitivity and specificity were determined to be 95.8% and 87.9%, respectively, whereas the Alvarado score was 71.1% sensitive and 75.8% specific. RIPASA score has a PPV and NPV of 98.88% and 97.67% compared to the Alvarado scores of 96.84% and 21.82%. The RIPASA and Alvarado scores’ diagnostic accuracy was 97.67% and 69.33%, respectively.

Chisthi et al. have conducted a study in India which reported RIPASA as 87.78% sensitive, 76.47% specific with a diagnostic accuracy of 85.98% (8). Another study conducted in Saudi Arabia by Maksoud et al. have shown a phenomenal RIPASA sensitivity of 96% which was comparable to our results i.e., 95.8% sensitive (18). Regar et al. have conducted a study in India that revealed results comparable to our study, however, with a significantly low specificity of RIPASA (3). Chavan et al. have compared the two scoring systems i.e., Alvarado versus RIPASA and reported results comparable to our study (19). Noor et al. have conducted a study in Peshawar, Pakistan recruiting 300 participants revealed the RIPASA sensitivity and specificity at 98.5% and 90%, respectively (20). These values are comparable and slightly better from the results reported in our study. A study recently conducted in Karachi has evaluated 384 patients and shown RIPASA score sensitivity, specificity, and diagnostic accuracy of 95.98% (95% CI 93.36-97.59), 91.67% (95% CI 78.17- 97.13) and 95.57% (95% CI 93.03-97.22) (21). RIPASA specificity reported in this study is slightly better but overall results are comparable to our study.

This study was conducted at a single centre, which may limit the generalizability of the findings. It is recommended that future studies with larger sample sizes should be conducted at multiple centres to further investigate this topic. Moreover, the research focused on individuals who underwent an appendectomy procedure. Cases that did not involve surgery were not taken into account during the study, thus restricting the applicability of the findings to only those who received surgical treatment. Consequently, the outcomes cannot be universally applied to all patients who presented with symptoms of pain in the right lower quadrant.

Conclusion

Compared to the Alvarado scoring system, the RIPASA grading system is superior in terms of accuracy, sensitivity, and specificity providing a reliable predictor for the diagnosis of acute appendicitis. Frequent implementation of the RIPASA grading system in our setting will lessen patient morbidity, shorten hospital stays, and lower the burden of healthcare costs. It can also prevent the need for expensive imaging examinations, which is especially advantageous for the public system in a country with a lower-middle income level.

Cite this article as: Din SSU, Baig IU, Hussain MT, Sadiq A, Humayun T, Ahmed U, et al. RIPASA versus Alvarado score in the assessment of acute appendicitis: A prospective study. Turk J Surg 2023; 39 (3): 231-236.

This study was approved by Federal Government Polyclinic Ethics Committee (Decision no: FGPC.1/12/2020, Date: 16.12.2021).

Externally peer-reviewed.

Concept - SSuD; Design - MTH, AS, TH, UA; Supervision - SSuD, IUB, MTH; Fundings - IUB; Materials - SSuD, IUB, MTH; Data Collection and/or Processing - AS, TH, UA, AS; Analysis and/or Interpretation - AS, TH, UA, AS; Literature Search - TH, UA, AS; Writing Manuscript - SSuD, AS, TH, UA, AS; Critical Reviews - SSuD, IUB, MTH, AS, TH, UA, AS.

The authors have no conflicts of interest to declare.

The authors declared that this study has received no financial support.

References

1. Stephens PL, Mazzucco JJ. Comparison of ultrasound and the Alvarado score for the diagnosis of acute appendicitis. Conn Med 1999; 63(3): 137-40.
2. Cuschieri A. The small intestine and vermiform appendix. In: Cuschieri A, Giles GR, Moossa AR, eds. Essential surgical practice. 3rd ed. London: Butterworth Heinemann; 1995. p. 1325-8.
3. Regar MK, Choudhary GS, Nogia C, Pipal DK, Agrawal A, Srivastava H. Comparison of Alvarado and RIPASA scoring systems in diagnosis of acute appendicitis and correlation with intraoperative and histopathological findings. Int Surg J 2017; 4(5): 1755-61. https://doi. org/10.18203/2349-2902.isj20171634
4. Alvarado A. A practical score for the early diagnosis of acute appendicitis. Ann Emerg Med 1986; 15(5): 557-64. https://doi.org/10.1016/ S0196-0644(86)80993-3
5. Chan J, Fan KS, Mak TLA, Loh SY, Ng SWY, Adapala R. Preoperative imaging can reduce negative appendectomy rate in acute appendicitis. Ulster Med J 2020; 89(1): 25-8.
6. Shaligram A, Pallati P, Simorov A, Meyer A, Oleynikov D. Do you need a computed tomographic scan to evaluate suspected appendicitis in young men: An administrative database review. Am J Surg 2012; 204(6): 1025-30. https://doi.org/10.1016/j.amjsurg.2012.05.024
7. Dezfuli SAT, Yazdani R, Khorasani M, Hosseinikhah SA. Comparison between the specificity and sensitivity of the RIPASA and Alvarado scoring systems in the diagnosis of acute appendicitis among patients with complaints of right iliac fossa. AIMS Public Health 2020; 7(1): 1-9. https://doi.org/10.3934/publichealth.2020001
8. Chisthi M, Surendran A, Narayanan J. RIPASA and air scoring systems are superior to Alvarado scoring in acute appendicitis: Diagnostic accuracy study. Ann Med Surg (Lond) 2020; 59: 138-42. https://doi. org/10.1016/j.amsu.2020.09.029
9. Chong CF, Adi MI, Thien A, Suyoi A, Mackie AJ, Tin AS, et al. Development of the RIPASA score: A new appendicitis scoring system for the diagnosis of acute appendicitis. Singapore Med J 2010; 51(3): 220- 5.
10. Shuaib A, Shuaib A, Fakhra Z, Marafi B, Alsharaf K, Behbehani A. Evaluation of modified Alvarado scoring system and RIPASA scoring system as diagnostic tools of acute appendicitis. World J Emerg Med 2017; 8(4): 276-80. https://doi.org/10.5847/ wjem.j.1920-8642.2017.04.005
11. Abu Foul S, Egozi E, Assalia A, Kluger Y, Mahajna A. Is early appendectomy in adults diagnosed with acute appendicitis mandatory? A prospective study. World J Emerg Surg 2019; 14(1): 44. https://doi. org/10.1186/s13017-018-0221-2
12. Williams GR. Presidential address: A history of appendicitis. With anecdotes illustrating its importance. Ann Surg 1983; 197(5): 495-506. https://doi.org/10.1097/00000658-198305000-00001
13. Kumar V, Cotran RS, Robbins SL. Appendix. In: Robbin’s Basic Pathology. 5th ed. London: WB Saunders; 199.
14. Pal KM, Khan A. Appendicitis, a continuing challenge. J Pak Med Assoc 1998; 48(7): 189-92.
15. Chan I, Bicknell SG, Graham M. Utility and diagnostic accuracy of sonography in detecting appendicitis in a community hospital. AJR Am J Roentgenol 2005; 184(6): 1809-12. https://doi.org/10.2214/ ajr.184.6.01841809
16. Flum DR, McClure TD, Morris A, Koepsell T. Misdiagnosis of appendicitis and the use of diagnostic imaging. J Am Coll Surg 2005; 201(6): 933-9. https://doi.org/10.1016/j.jamcollsurg.2005.04.039
17. Ozao-Choy J, Kim U, Vieux U, Menes TS. Incidental findings on computed tomography scans for acute appendicitis: Prevalence, costs and outcome. Am Surg 2011; 77(11): 1502-9. https://doi. org/10.1177/000313481107701141
18. Abd El Maksoud W, Bawahab M, Al Shehri D, Mostafa O, Ali H, Alwail A, et al. Comparison between the validity of the ‘Modified Alvarado’ and ‘Raja Isteri Pengiran Anak Saleha’ scores for the diagnosis of acute appendicitis. Egypt J Surg 2017; 36(1): 52. https://doi.org/10.4103/1110- 1121.199891
19. Chavan S, Bhatnagar S, Bendre M, Sinha N. Comparative study of alvarado score and Raja Isteri Pengiran Anak Saleha appendicitis (RIPASA) score in the diagnosis of acute appendicitis. Int Surg J 2018; 5(4): 1330-4. https://doi.org/10.18203/2349-2902.isj20180001
20. Noor S, Wahab A, Afridi G, Kaleemullah. Comparing RIPASA score and Alvarado score in an accurate diagnosis of acute appendicitis. J Ayub Med Coll Abbottabad 2020; 32(1): 38-41.
21. Salahuddin F, Qureshi A. Diagnostic utility of RIPASA and modified Alvarado scoring system in acute appendicitis in Karachi, Pakistan. Pak J Surg 2022; 38(3): 126-30.