Archives of Academic Emergency Medicine. 2020; 8(1): e20 OR I G I N A L RE S E A RC H Accuracy of Alvarado, Eskelinen, Ohmann, RIPASA and Tzanakis Scores in Diagnosis of Acute Appendicitis; a Cross-sectional Study Mustafa Korkut1, Cihan Bedel1∗, Yusuf Karancı1, Ali Avcı2, Murat Duyan1 1. Department of Emergency Medicine, Health Science University Antalya Training and Research Hospital, Antalya, Turkey. 2. Department of Emergency Medicine, Karaman State Hospital, Karaman, Turkey. Received: January 2020; Accepted: February 2020; Published online: 13 March 2020 Abstract: Introduction: Many scoring systems have been developed to assist in diagnosis of acute appendicitis (AA). This study aimed to compare the screening performance characteristics of Alvarado, Eskelinen, Ohmann, Raja Isteri Pengiran Anak Saleha (RIPASA), and Tzanakis scores in predicting the need for appendectomy in AA patients. Methods: Our study prospectively evaluated AA patients that were treated in a tertiary hospital’s emergency de- partment. The obtained data were used to calculate Alvarado, Tzanakis, RIPASA, Eskelinen and Ohmann scores. Patients were categorized into two groups according to their histopathological results: positive (PA) and nega- tive appendectomy (NA). The accuracy of different scoring systems in diagnosing AA was investigated. Results: 74 patients suspected to AA with the mean age of 36.68 ± 11.97 years were studied (56.8% male). The diagno- sis was histopathologically confirmed in 65 cases (87.8%). Median Alvarado, Tzanakis, RIPASA, Eskelinen and Ohmann scores were significantly higher in patients with positive appendectomy. The area under the curve (AUC), sensitivity, and specificity of Tzanakis score in the cut-off value of 8 were 0.965, 84.4%, and 100%, re- spectively. For Ohmann and Alvarado scores, these measures were 0.941; 71.9%, 89.9% and 0.938, 60.9%, 89.9%, respectively. Tzanakis scoring system had the best screening performance in detection of cases with AA. Con- clusion: Tzanakis score is more sensitive and specific than Alvarado, RIPASA, Eskelinen and Ohmann scores in identifying AA patients needing appendectomy. Keywords: Appendicitis; Emergency Medicine; Diagnosis; Sensitivity and Specificity; Alvarado, Eskelinen, Ohmann, Raja Isteri Pengiran Anak Saleha Appendicitis, Tzanakis Cite this article as: Korkut M, Bedel C, KarancıY, AvcıA, Duyan M. Accuracy of Alvarado, Eskelinen, Ohmann, RIPASA and Tzanakis Scores in Diagnosis of Acute Appendicitis; a Cross-sectional Study. Arch Acad Emerg Med. 2020; 8(1): e20. 1. Introduction Acute appendicitis (AA) is the most common reason for surgi- cal intervention among patients admitted to the emergency department (ED) with abdominal pain (1). Approximately one-third of AA cases present with atypical clinical symptoms (2). Perforation and negative appendectomy (NA) rates were as high as 12-21% and 13-36%, respectively, for patients that were diagnosed solely through physical examinations (3, 4). In recent years, many scoring systems have been developed based on anamnesis scores, clinical symptoms and findings, ∗Corresponding Author: Cihan Bedel; Health Science University Antalya Training And Research Hospital, Kazım Karabekir Street postal zip code: 07100, Muratpasa, Antalya, Turkey. Phone: +905075641254, Fax: +902422494487, E- mail: cihanbedel@hotmail.com and inflammatory parameters, to assist in diagnosis of AA (5- 8). The Alvarado score is the first of these systems. It is based on symptoms, and clinical and laboratory results (9). Then Raja Isteri Pengiran Anak Saleha (RIPASA) system was devel- oped for patients in Asia. In recent years Eskelinen, Ohmann and Tzanakis scores, which added radiological methods such as ultrasound to the scoring systems; clinical and laboratory findings were also followed. These scoring systems aim to re- duce NA and mortality/morbidity rates by preventing com- plications (5-10). Despite being inexpensive, reproducible and easy-to-use with high success rates, these systems still have not become a part of routine practice. This study aimed to compare the screening performance characteristics of Alvarado, Eskeli- nen, Ohmann, RIPASA and Tzanakis scores in predicting the need for appendectomy in AA patients. This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem M. Korkut et al. 2 2. Methods 2.1. Study design and setting In this prospective cross-sectional study, patients who were admitted to the emergency department of a tertiary hospi- tal (Health Science University Antalya Training and Research Hospital, Antalya, Turkey) with abdominal pain suspected to AA between May 2, 2019 and December 1, 2019 were eval- uated. This study was approved by the ethics committee of the hospital (Ethics code: 2019-129). All subjects consented to participate in the study, and the data were recorded by ED physicians. 2.2. Participants All cases with abdominal pain suspected to AA, who were referred to ED during the study period, were included us- ing non-probability sampling method. The exclusion criteria were as follows: (a) being under 18 years of age, (b) elective appendectomy, (c) incarcerated or inguinal hernia, (d) non- operable patients, (e) not accepting hospitalization, and (f ) incomplete data. 2.3. Data gathering The following data were recorded for all subjects: com- plaints at the time of admission, and examination and lab- oratory findings. Significant ultrasonography (US) and ab- dominal computed tomography (CT) scan findings were also recorded. The following US findings indicated acute appen- dicitis: (a) non-compressible, (b) >6 mm outer diameter, (c) appendicolith, (d) target appearance in axial section, and (e) periappendiceal inflammation with fat stranding. The fol- lowing CT findings indicated acute appendicitis: (a) dilated lumen (≥7mm), (b) appendicolith, (c) periappendiceal fluid collection, and (d) inflamed mesoappendix. The obtained data were used to calculate Alvarado, Tzanakis, RIPASA, Es- kelinen and Ohmann scores. All patients underwent appen- dectomy and were categorized into two groups according to histopathologic diagnosis: positive appendectomy (PA) and negative appendectomy (NA). 2.4. Evaluated Scores Alvarado The Alvarado system evaluates 8 parameters, which include symptoms, clinical findings and leukocyte count. The high- est possible score is 10, and appendectomy is recommended for scores >7 (11). Ohmann and Eskelinen The Ohmann score is also composed of 8 parameters (Ten- derness in right lower quadrant, rebound tenderness, pres- ence of urinary system complaint, character of pain, relo- calization of pain to the right lower quadrant, age, leukocyte count, abdominal rigidity), a score ≥12 indicates AA (12). In Figure 1: Area under the curve (AUC) of rapid emergency medicine score (REMS) and rapid acute physiology score (RAPS) in prediction of in-hospital mortality and poor outcome. addition to these parameters, the Eskelinen scoring system also considers the duration of pain and laboratory results. A score >57 indicates AA (13). RIPASA and Tzanakis Tzanakis et al. developed a scoring system consisting of 4 simplified variables and 15 points based on the combina- tion of clinical evaluation, ultrasonography and laboratory parameters. RIPASA is a scoring system developed for the Asian and middle-eastern population with 15 objective pa- rameters obtained during routine history taking, physical ex- amination, and haematological assessment and urinalysis. A RIPASA score >12 and a Tzanakis score >8 indicate AA (8, 14). 2.5. Statistical Analysis The data were analysed using SPSS version 18.0. Descriptive statistics for categorical data are expressed as numbers and percentages, while mean ± standard deviation and median (minimum-maximum) were used to express continuous data based on normal distribution. Student’s t-test was used for variables with normal distribution, and Mann-Whitney U- test was used for variables without normal distribution. The screening performance characteristics of the scoring systems were measured. A greater area under the receiver operating characteristic (ROC) curve (AUC) indicates better diagnostic value. p<0.05 was considered statistically significant. 3. Results 3.1. Baseline characteristics of studied cases The study included a total of 74 patients with a preliminary AA diagnosis: 42 males (56.8%) and 32 females (43.2%). Ta- ble 1 shows the baseline characteristics of studied cases. The This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 3 Archives of Academic Emergency Medicine. 2020; 8(1): e20 Table 1: Baseline characteristics of studied patients Variables Values (n=74) Age (year) Median (min-max) 33 (18-63) Mean ± standard deviation 36.68 ± 11.97 Gender(n, %) Male 42 (56.8) Female 32 (43.2) Appendectomy findings for AA Positive 65 (87.8) Negative 9 (12.2) Histopathological findings, n (%) Acute appendicitis 53 (71.6) Perforated appendicitis 7 (9.4) Lymphoid hyperplasia 3 (4.0) Unusual histopathological findings 2 (2.8) Appendix vermiformis 8 (10.8) Others 1 (1.4) Clinical findings, n (%) Sensitivity on lower right quadrant 64 (86.5) Defense-rigidity 49 (66.2) Rebound 44 (59.5) Fever (>37.3◦) 27 (36.5) Nausea-Vomiting 26 (35.1) Laboratory findings WBC count (×103 /mm3 ) 14.12±4.71 Neutrophils (×103 /mm3 ) 11.10±4.57 Lymphocytes (×103 /mm3 ) 1.95±0.82 C-reactive protein (mg/dL) 24 (0-331) Scores, median (min-max) Alvarado 7 (2-10) Ohmann 13 (4-16) RIPASA 10 (4.5-13.5) Tzanakis 13 (3-15) Eskelinen 51.1 (29.8-67.6) AA: acute appendicitis; WBC: white blood cell; RIPASA: Raja Isteri Pengiran Anak Saleha Appendicitis. median age was 33 (range: 18-63) years. The diagnosis was histopathologically confirmed in 65 cases (87.8%). Among these, 7 patients (9.4%) had perforated AA and 3 (4.0%) had lymphoid hyperplasia. 9 (12.2%) patients had negative ap- pendectomy, 1 of these (1.4%) being ovarian cyst rupture. The mean white blood cell (WBC) count was 14.12 ± 4.71 ×103/mm3. The median scores of different systems were as follows: Alvarado score 7 (2-10); Ohmann score 13 (4-16); RI- PASA score 10 (4.5-13.5); Tzanakis score 13 (3-15); Eskelinen score 51.1 (29.8-67.6). 3.2. Comparing the scores Table 2 compares the baseline characteristics as well as scores between cases with negative and positive appendec- tomy. Median age was significantly higher in patients with positive appendectomy (p=0.006). There was no significant difference between patients with positive and negative ap- pendectomy regarding gender (p=0.163). Ultrasonography results were not sufficient for diagnosing AA (p = 0.501); how- ever, computed tomography (CT) scans were able to signifi- cantly determine AA (p <0.001). Median Alvarado, Tzanakis, RIPASA, Eskelinen and Ohmann scores were significantly higher in patients with positive appendectomy. Screening performance characteristics of the studied sys- tems in determining cases with AA are presented in table 3 and figure 1. Tzanakis score was able to determine AA bet- ter than the other scoring systems, followed by Ohmann and Alvarado scores, respectively (based on AUC). AUC, sensitiv- ity, and specificity of Tzanakis score in the cut-off value of 8 were 0.965, 84.4%, and 100%, respectively. For Ohmann and Alvarado scores, these measures were 0.941; 71.9%, 89.9% and 0.938, 60.9%, 89.9%, respectively. Tzanakis scoring sys- tem had the best screening performance in detection of cases with AA. 4. Discussion Based on the findings of the present study, Tzanakis score has higher sensitivity and specificity in the diagnosis of AA com- pared to Alvarado, RIPASA, Eskelinen and Ohmann scores. The differential diagnosis of AA only requires simple physi- cal and laboratory analyses; however, it is commonly misdi- agnosed due to atypical findings. Perforation and NA rates are still significantly high. The importance of timely and pre- cise diagnosis has led researchers to develop different scor- ing systems (15). Alvarado is the first and most widely used among them (10). It is simple, easy-to-use and can success- fully predict AA (16). Subraman et al. reported the sensitivity and specificity of Alvarado score to be 68% and 86.96%, re- spectively (17). Whereas, Elhosseiny et al. found these val- ues to be 65.2% and 100%, respectively (18). We have found the sensitivity and specificity of Alvarado scores to be 60.9% and 89.9%, respectively. Khan et al. reported NA and perfo- rated appendectomy rates to be 15.6% and 7.8%, respectively (19). Researchers have been trying to develop better diagnos- tic methods to decrease these numbers. Studies suggest that the RIPASA score is more accurate than the Alvarado score, especially in Eastern societies (18). Frountzas et al. studied 2161 cases of AA and found that while the RIPASA system was more sensitive, it had a lower speci- ficity than the Alvarado system (20). Chong et al. studied the RIPASA scoring system, and found that it had 97.5% sensi- tivity, 81.8% specificity and 91.8% diagnostic accuracy (21). We have found that the AUC for the RIPASA score was slightly lower than the Alvarado score (0.893 vs. 0938). The Ohmann score is a simple test that can help diagnose pa- tients with suspected AA (22). Similarly, the Eskelinen score is considerably successful in ruling out the diagnosis of AA (23). Erdem et al. found that the sensitivity and specificity of the Ohmann and Eskelinen scores 96% and 42%, and 100% and This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem M. Korkut et al. 4 Table 2: Comparing the baseline characteristics as well as acute appendicitis scores between cases with positive and negative appendectomy findings Variables Appendectomy findings P value Negative (n=9) Positive (n=65) Age (years) Median (min-max) 27 (19-46) 36 (18-63) 0.006 Gender, n (%) Male 3 (33.3) 39 (60) 0.163 Female 6 (66.7) 26 (40) Ultrasonography findings, n (%) Negative 5 (55.6) 28 (43.1) 0.501 Positive 4 (44.4) 37 (56.9) Computed tomography scan find- ings, n (%) Negative 5 (71.4) 2 (3.6) <0.001 Positive 2 (28.6) 55 (96.4) Laboratory findings WBC count (×103 /mm3 ) 10.38±3.00 14.64±4.69 0.01 Neutrophils (×103 /mm3 ) 7.10±2.91 11.66±4.51 0.004 Lymphocytes (×103 /mm3 ) 2.60±0.85 1.86±0.78 0.022 C-reactive protein (mg/dL) 9 (0-321) 33 (0-331) <0.001 Clinical findings, n (%) Sensitivity on lower right quadrant 3 (33.3) 61 (93.8) <0.001 Defense guarding 3 (33.3) 46 (70.8) 0.026 Rebound 3 (33.3) 41 (63.1) 0.146 Fever (>37.3◦) 4 (44.4) 23 (35.4) 0.716 Nausea-Vomiting 2 (22.2) 24 (36.9) 0.480 Scores, median (min-max) Alvarado 4 (2-5) 7 (3-10) <0.001 Ohmann 8 (4-13) 13.5 (8-16) <0.001 RIPASA 6 (4.5-8) 10 (4.5-13.5) <0.001 Tzanakis 4 (3-7) 13 (3-15) <0.001 Eskelinen 35.1 (33.8-49.2) 53.9 (29.8-67.6) <0.001 WBC: White blood cell; RIPASA: Raja Isteri Pengiran Anak Saleha Appendicitis; min: minimum; max: maximum. Table 3: Screening performance characteristics of different scoring systems in prediction of acute appendicitis in emergency department Alvarado Ohmann RIPASA Tzanakis Eskelinen TP 40 47 55 56 42 TN 8 8 8 8 7 FP 1 1 1 1 2 FN 25 18 10 9 23 Sensitivity 60.9 (48.64-73.35) 71.9 (59.81-82.69) 75 (64.81-86.47) 84.4 (75.34-93.47) 64.1 (51.77-76.08) Specificity 89.9 (51.75-99.72) 89.9 (51.75-99.72) 99.72 (51.75-100) 99.88 (51.75-99.72) 78 (39.99-99.19) PPV 97.56 (86.19-99.61) 97.92 (88.04-99.67) 98.04 (88.69-99.69) 98.25 (89.80-99.72) 95.45 (85.93-98.63) NPV 24.24 (17.89-31.98) 30.77 (21.98-41.21) 34.78 (24.44-46.80) 47.06 (31.72-62.97) 23.33 (15.86-32.96) PLR 5.54 (0.86-35.56) 6.51 (1.02-41.55) 6.92 (1.09-44.15) 7.75 (1.22-49.24) 2.91 (0.85-10.00) NLR 0.43 (0.29-0.64) 0.21 (0.20-0.49) 0.26 (0.16-0.43) 0.16 (0.08-0.30) 0.45 (0.28-0.73) AUC 0.93 (0.87-0.99) 0.94 (0.88-1.00) 0.89 (0.81-0.97) 0.96 (0.90-1.00) 0.86 (0.77-0.97) Data are presented with 95% confidence interval (CI). Measures are calculated in cut-offs: ≥8 for Alvarado score; ≥12 for Ohmann score; ≥12 for RIPASA score; ≥8 for Tzanakis score; ≥57 for Eskelinen score. 44%, respectively (24). We found that Ohmann and Eskelinen scores failed to diagnose AA, but they were sufficiently spe- cific. The Eskelinen score is at a disadvantage due to its dec- imal calculations that make it less practical. It also may re- quire additional diagnostic methods, such as laboratory test- ing or ultrasonography, for differential diagnosis. The Tzanakis score was suggested as a combined clinical evaluation of US results and inflammatory markers, the high- est possible score is 15, and ≥8 indicates AA. The sensitiv- ity and specificity were 95.4% and 97.4%, respectively (25). This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 5 Archives of Academic Emergency Medicine. 2020; 8(1): e20 Sigdel et al. reported that the Tzanakis score was as effec- tive as the Alvarado score, with a lower false-negative rate (26). Studies show sensitivity levels to be between 85-96%, but Sigdel et al. attribute these low rates to differences in the experience levels of radiologists that perform US (26, 27). 5. Limitation The limitations of our study are as follows: (a) the relatively small sample size despite the prospective nature of the study, and (b) different physicians deciding for appendectomy for different cases. Further prospective studies with larger sam- ple sizes are required to support our findings. 6. Conclusion Tzanakis score has higher sensitivity and specificity in diag- nosis of AA compared to Alvarado, RIPASA, Eskelinen and Ohmann scores. 7. Declarations 7.1. Acknowledgements The author would like to thank MD. Aysegul Korkut for help- ing in preparation of this paper. 7.2. Author contribution All the authors made a substantial contribution in study design, data interpretation and writing and reviewing the manuscript. Authors ORCIDs Mustafa Korkut: 0000-0003-1665-1601 Cihan Bedel: 0000-0002-3823-2929 Yusuf Karancı: 0000-0003-0230-2187 Ali Avcı: 0000-0002-7019-1012 Murat Duyan: 0000-0002-6420-3259 7.3. Ethical approval Ethics committee approval was received for this study. 7.4. Funding/Support No funding and support was received for this study. 7.5. Conflict of interest The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. References 1. Karaman K, Ercan M, Demir H, Yalkın O, Uzunoglu Y, GUndogdu K, et al. The Karaman score: A new diagnos- tic score for acute appendicitis. Ulus Travma Acil Cerrahi Derg. 2018;24(6):545-51. 2. Dal F, Cicek Y, Pekmezci S, Kocazeybek B, Tokman HB, Konukoglu D, et al. 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Downloaded from: http://journals.sbmu.ac.ir/aaem Introduction Methods Results Discussion Limitation Conclusion Appendix References