Acute appendicitis still ranks as one of the most common surgical emergency that despite the extraordinary advances in radiographic imaging and laboratory tests, the accurate diagnosis of acute appendicitis still remains a challenging issue. Acute appendicitis is inflammation of the vermiform appendix and is the most common acute surgical emergency in all ages and comprises 10% of surgical cases in the emergency department [1] the pathophysiology of appendicitis may result from obstruction of the appendiceal orifice. This results in inflammation, localized ischemia, perforation and the development of a contained abscess or frank perforation with resultant peritonitis [2], Clinical presentation of acute appendicitis may be typical or atypical. Typical presentation starts with vague peri-umbilical pain for several hours, which later migrates to the Right Iliac Fossa (RIF), associated with lack of appetite, nausea, or vomiting. Atypical histories lack this typical progression and may include pain in the right lower quadrant as an initial symptom [3]. As inflammation progresses, signs of peritoneal inflammation develop. 

Diagnosis

The diagnosis is based on history and physical examination which can be supported by:

• Laboratory Investigation: There is elevated White Blood Cells (WBC) with or without a left shift or bandemia, up to one-third will present with a normal WBC count

• Imaging Studies: Abdominal Ultrasound, computed tomography and magnetic resonance imaging all can be utilized as a diagnostic tools for the diagnosis of appendicitis

• Scoring Systems: A number of scoring systems have been developed to try to identify people who are likely to have appendicitis. These include the following

The Alvarado Score and its Interpretation

In 1986, Alvarado score was introduced by Alfredo Alvarado in 1986. It was meant for diagnosis of pregnant females with acute appendicitis but then it was authorized for the general population as well. It was designed to be simple, inexpensive, noninvasive and easily repeatable. Alvarado constructed a 10-point clinical scoring system for the diagnosis of acute appendicitis as based on symptoms, signs and diagnostic tests in patients presenting with suspected acute appendicitis [4,5] as shown in Figure 1.

Figure 1: The Alvarado Score and its Interpretation (5)

RIPASA Score and its Interpretation

One of clinical diagnostic systems based on scoring of various clinical and laboratory findings of patients that have been developed for diagnosing of acute appendicitis, was the Raja Isteri Pengiran Anak Saleha appendicitis (RIPASA) score, created by Dr. William Chong (cardiovascular and general surgeon) in Brunei, which is a useful rapid diagnostic tool used widely across the world and involves 14 clinical parameters [6,7], as shown in Figure 2.

Figure 2: RIPASA Scoring System and its Interpretation [7]

Patients and Methods

A prospective comparative study that was conducted in the Department of General Surgery at Al-Yarmouk Teaching Hospital/Baghdad during the period of one year from 1st of February 2019 till 1st of February 2020. The study included 200 patients attended the outpatient clinic or the emergency department complaining from lower abdominal and/or right iliac fossa pain suggestive of acute appendicitis. Patients who aged below 5 years, had signs and symptoms of perforated viscous, those with previous history of intra-abdominal surgery, those who presented with right iliac fossa mass and pregnant women all were excluded from the current study.The decision on patient management; by discharge, observation, further diagnostic studies or appendectomy was left to the discretion of the treating surgeon and confirmed by intraoperative assessment and postoperative histopathological result which in turn help us in assessing the accuracy of RIPASA scoring system in comparison to ASS. The individual scores were then compared to the final diagnosis made by the clinician and to the recommendations of each scoring system. The final diagnosis of pathology had been done according to histopathological result postoperatively. Patients who were adjudged not to have appendicitis by the attending clinician were discharged home on analgesics we follow up them by phone calls and instructed to make a contact with us if any worsening or persistence of symptoms. Verbal permission was obtained from each patient prior to collecting data and information were anonymous. Names were removed and replaced by identification codes. All information kept confidential in a password secured laptop and data used exclusively for the research purposes. The data analyzed using Statistical Package for Social Sciences (SPSS) version 25. The data presented as mean, standard deviation and ranges. Categorical data presented by frequencies and percentages. Analysis of Variance (ANOVA) (two tailed) was used to compare the continuous variables accordingly. Chi square test was used to assess the association between provisional diagnosis and certain parameters. A level of p-value less than 0.05 was considered significant.

The total number of study patients was 200. They were complained from lower abdominal and/or right iliac fossa pain suggestive of acute appendicitis. The distribution of study patients by age and gender is shown in figures and. Study patients’ age was ranging from 8 to 52 years with a mean of 23.2 years and a standard deviation (SD) of ±7.21 years. The highest proportion of study patients was aged <20 (52%). Regarding gender, males was slightly higher than females (58% versus 42%) with a male to female ratio of 1.38:1. In this study, 59% of study patients were complained from pain for less than 48 hrs. Most of study patients had right iliac fossa tenderness (96%); nausea and/or vomiting (93%); and anorexia (90.5%). Table 1 showed the distribution of patients according to their clinical information.

Table 1: Distribution of Study Patients by Clinical Information 

The association between the diagnosis and certain characteristics are shown in Table 2 whereby p- value was statically significant for Anorexia, Rebound tenderness, Leukocytosis, Migratory pain, ROVSING sign and right Iliac Fossa Pain (RIF) (p-value is less than 0.05).

Table 2: Association between Diagnosis and Certain Characteristics 

Most of the patients (172 patients, 86%) underwent appendectomy. the specimens had been send for histopathological diagnosis, where the results were tabulated in Table 3.

Table 3: Histopathological Findings Regarding those who Underwent Appendectomy

Sensitivity (SN), Specificity (SP), Positive Predictive Value (PPV), negative predictive value and accuracy of ALVARADO score are shown in Table 4.

Table 4: Sensitivity (SN), Specificity (SP), Positive Predictive Value (PPV), Negative Predictive value and Accuracy of ALVARADO score

Sensitivity (SN), Specificity (SP), Positive Predictive Value (PPV), negative predictive value and accuracy of RIPASA score are shown in Table 5.

Table 5: Sensitivity (SN), Specificity (SP), Positive Predictive Value (PPV), Negative Predictive Value and Accuracy of RIPASA Score

Comparing both scores in terms of sensitivity, specificity, accuracy, positive predicted value and negative predicted value are shown in Table 6, where RIPASA score was more sensitive than ALVARADO score (94.1% vs. 69.7%) but less specific (62.5% vs. 87.5%) and higher accuracy (86.5% vs. 74%) respectively.

Table 6: Sensitivity, Spceficity. Accuracy, NPV, PPV of RIPASA and ALVARADO Scoring System

Acute appendicitis is one of the most common surgical emergencies, with a lifetime prevalence rate of approximately one in seven. Despite being a common problem, it still a difficult diagnosis to establish, especially among the young, the elderly and females of reproductive age, where a host of other genitourinary and gynecological inflammatory conditions can present with signs and symptoms that are similar to those of acute appendicitis [8]. Alvarado score was selected to aid in the decision making process because of its simple design and application. Also, it has been reported that a scoring system, such as the present one, has the same diagnostic accuracy as computer aided techniques [4]. Other studies found that RIPASA score is a better, easy, safe and non-invasive diagnostic tool for diagnosis of acute appendicitis especially in scenario where most of population is rural where radiological diagnostic tools are not easily available and even in the area of availability, affordability becomes the issue for middle class patient, so significant reduction in health care cost can be done [9]. In the current study, 44.8% of the operated cases were diagnosed as catarrhal appendicitis and 11.6% of them had normal appendix (negative appendectomy). By comparison to other studies, Singh et al. [9], observed that rate of negative appendectomy was higher compared to the current results (16%), another different results observed in Chong et al. [10], as found that rate was 16.3% and was 10.6% in Nanjundaiah et al. [8]. In the current study RIPASA score was 94.1% sensitive, 62.5% specific and 86.5% accurate. PPV was 88.8% and NPV was 76.9%. These results were compared with other studies, as Nanjundaiah et al. [8], which compared sensitivity and specificity between Alvarado scoring system with that of RIPASA score, sensitivity and specificity of RIPASA score were 96.2 and 90.5% respectively, while sensitivity and specificity of Alvarado score were 58.9 and 85.7% respectively. They concluded that RIPASA scoring system is more convenient, accurate and specific scoring system than Alvarado scoring system [8]. Singh et al. study in 2018, they reported that sensitivity of the RIPASA score was 95.89%, specificity 75.92%, PPV 91.50% and NPV 87.23% with diagnostic accuracy of 90.5%. They concluded that by applying RIPASA scoring system, there is reduction of negative appendectomy rate by 3.85% and mean duration of hospital stay [9], this result was in accordance with previous studied on RIPASA score like Chong et al. [10], as reported that sensitivity was 97.5%, specificity of 81.8%, PPV of 86.5%, NPV of 96.4% and a diagnostic accuracy of 91.8%. Another comparable results observed in Butt et al. [11], as noticed that sensitivity of RIPASA score was 96.7%, specificity 93.0%, diagnostic accuracy was 95.1%, PPV was 94.8% and NPV value was 95.54%, concluded that RIPASA was a useful tool to diagnose appendicitis, in equivocal cases of pain.

The current study showed that RIPASA score is more accurate and more sensitive than Alvarado score, in spite of the lower specificity, so that it can be effectively conducted for the better evaluation of acute appendicitis, it is a simple, non-invasive and cost effective way to be used in resource limited conditions.

Recommendations

We recommend to do larger studies with larger sample size and longer duration to confirm the current results and to compare the sensitivity, specificity and accuracy according to certain characteristics as age, gender and duration of pain.

1. Williams, Norman et al. Bailey and Love's Short Practice of Surgery. 27th Edn., CRC Press, 2018, p. 1299.

2. Khan, M.S.C.M. et al. “Risk of appendicitis in patients with incidentally discovered appendicoliths.” Journal of Surgical Research, vol. 221, no. 1, 2018, pp. 84–87.

3. Doherty, G.M. Current Diagnosis and Treatment: Surgery. Lange Medical Books/McGraw-Hill, 2010.

4. Alvarado, A.J. “A practical score for the early diagnosis of acute appendicitis.” American Journal of Emergency Medicine, vol. 15, no. 5, 1986, pp. 557–564.

5. Ohle, R. et al. “The alvarado score for predicting acute appendicitis: A systematic review.” BMC Medicine, vol. 9, 2011, p. 139.

6. Chong, C.F. et al. “Development of the RIPASA score: A new appendicitis scoring system for the diagnosis of acute appendicitis.” Singapore Medical Journal, vol. 51, no. 3, 2010, pp. 220–225.

7. Jain, A. and P. Kothiyal. “A Comparative Study of RIPASA Score and ALVARADO Score in Diagnosis of Acute Appendicitis.” International Journal of Science and Research (IJSR), vol. 7, no. 8, 2018, pp. 1091–1094.

8. Nanjundaiah, N. et al. “A comparative study of RIPASA Score and ALVARADO score in the diagnosis of acute appendicitis.” Journal of Clinical and Diagnostic Research (JCDR), vol. 8, no. 11, Nov. 2014, pp. NC03.

9. Singh, A. et al. “To determine validation of RIPASA score in diagnosis of suspected acute appendicitis and histopathological correlation with applicability to Indian Population: A Single Institute Study.” Indian Journal of Surgery, vol. 80, no. 2, 2018, pp. 113–117.

10. Chong, C. et al. “Development of the RIPASA score: A New appendicitis scoring system for the diagnosis of acute appendicitis.” Singapore Medical Journal, vol. 51, no. 3, 2010, p. 220. 

11. Butt, M.Q. et al. “RIPASA score: A new diagnostic score for diagnosis of acute appendicitis.” Journal of the College of Physicians and Surgeons Pakistan (JCPSP), vol. 24, no. 12, 2014, pp. 894–897.