Untitled Document

Original Article

Bull Emerg Trauma 2014;2(1):15-21.

Accuracy of Surgeon’s Intraoperation Diagnosis of Acute Appendicitis, Compared with the Histopathology Results

Nima Pourhabibi Zarandi1,2, Parisa Javidi Parsijani1, Shahram Bolandparvaz2, Shahram Paydar2*, HamidReza Abbasi2

1 Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
2Trauma Research Center, Shahid Rajaee (Emtiaz) Trauma Hospital, Shiraz University of Medical Sciences, Shiraz, Iran

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Corresponding author: Shahram Paydar
Address: Trauma Research Center, Shahid Rajaee (Emtiaz) Trauma Hospital, Shiraz University of Medical Sciences, Shiraz, Iran. Tel/Fax: +98-711-6254206, e-mail: paydarsh@gmail.com

Received: October 1, 2013
Revised: November 12, 2013
Accepted: December 20, 2013

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Please cite this paper as:
Pourhabibi Zarandi N, Javidi Parsijani P, Bolandparvaz S, Paydar S, Abbasi HR. Accuracy of Surgeon’s  Intraoperation Diagnosis of Acute Appendicitis, Compared with the Histopathology Results. Bull Emerg Trauma. 2014;2(1):15-21.

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Abstract

Objective: To evaluate the accuracy of surgeons’ intraoperative diagnosis in open appendectomy and compare it with the histopathology examination results afterwards.
Methods: This was a cross-sectional retrospective study accomplished in Namazee hospital affiliated with Shiraz University of Medical Sciences, in a one-year period from 2007 to 2008. Medical charts of all the patients who were admitted with impression of acute appendicitis and underwent open appendectomy in our center were included. Demographic information, intraoperative findings as in the operation note based on a method used by our  surgeons, and histopathology examination  of the removed appendix were recorded and reported. Results: A total of 342 patients were studied including 229 (67%) males and 113 (33%) females, with the mean age of 16.02 ± 9.89 (range 3 to 76) years, with a large proportion from 10 to 15 years. Surgeons reported 97.4% of the patients to have acute appendicitis,
29.5%, 10.2% and  5.6% with severe, moderate  and  mild inflammation  respectively, whereas 26.6%  and 9.4% with suppurated  and gangrenous  appendicitis  separately, 14.6% to  have perforated appendicitis and only 1.5%hadperforated appendicitis with peritonitis. However, 79.5% of cases showed appendicitis in the histopathology review. The accuracy of surgeons’ intraoperative diagnosis is 81.6%, 85.2% for men and 72.6% for women.
Conclusion: The method used by our surgeon is not completely indicative in mild to severe inflamed appendix but it is almost always compatible with the pathology results in suppurated, gangrened, and perforated appendix. Therefore surgeons’ gross observation of the  inflamed appendix  may not  always be in  concordance  with the  histopathology examination of the resected appendix.

Keywords: Appendicitis; Surgical findings; Histopathological findings; Intraoperative observations; Negative appendectomy.

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Introduction

Inflammation of  Appendix,  which  is  referred as  acute   Appendicitis, is a common intra-abdominal condition which needs immediate surgical intervention 1-3]. Surgical appendectomy remains the gold standard treatment of acute appendicitis, in spite of advanced modalities nowadays [4,5]. Acute appendicitis  is considered  to have a high  lifetime risk [6], which means about 7% of the individuals undergoing appendectomy during their living, 23.1% and 12% in females and males respectively [5,7]. The excision of appendix not  only decreases the risk of life-threatening complications including perforation  and sepsis, but  also allows for the histopathology examination which is the gold standard for confirmation the diagnosis of acute appendicitis, irrespective of  the  intraoperative  findings  [8-10]. If pathologist sees transmural  inflammation  of the appendix or granulocytes in the mucosa or infiltrated into the epithelium,then it is acute appendicitis [10,11]. However,open appendectomy has the disadvantage of    high    rate    of    negative   appendectomy [6], which is referred to  an appendectomy based on the clinical diagnosis of acute appendicitis but in which the histopathological examination of the appendix is normal [11]. In spite of the increasing role of advanced paramedical modalities such as ultrasonography and computed-tomography (CT scan) in the diagnosis of acute appendicitis, the rate of misdiagnosed cases of appendicitis has not been changed during these years (15.3%), same as the  rate  of perforated  appendix [12-14]. Since there is interobserver variation in   the   assessment   of  appendicitis   among   the surgeons [15], the histopathological examination of the appendectomy specimen is highly recommended [16].
The present study was carried out with the primary goal of assessing the accuracy of the criteria used by surgeons based on their observations in the operation room  (OR) for  describing the  inflamed  appendix and compares them with the histopathological examination afterwards in one of the largest hospital of southern Iran. It also aimed at determining the rate of negative appendectomy in our center.

Materials and Methods
Study Population
This study was a retrospective cross-sectional one including all patients  with the  first impression  of acute appendicitis admittedin  the ER of surgery in Nemazee hospital, one of the largest teaching hospitals in Iran  and  a tertiary health care center which is affiliated with Shiraz University of Medical Sciences (SUMS), and  underwent  open  appendectomy during  a  one-year  period  from  September  2007 to  September 2008. Patients  whose  medical  files had the required  information  and who underwent emergency open  appendectomy  were included. We excluded the patients who were scheduled for elective appendectomy, patients who underwent laparoscopic appendectomy and those with incomplete profile.

Study Protocol
Medical records of the patients were reviewed and the data was entered to a computer database. Alongside demographic information, our database included the findings reported  by the surgeon in the operation note describing what the surgeon observed. In this center, acute care surgery service is responsible for openappendectomy  operations; uses a classification method depending on the gross vascular appearance, consistency and the diameter of the appendix, and also any puss formation or fibrin deposition. According to this set of criteria, mild inflammation is a condition in which only the vasculature of the appendix become more prominent  than in normal condition, without any change in consistency and the diameter of the organ, and no puss formation or fibrin deposition. However, increase in the size of the
vasculature alongside with  the  hardening  of  the appendix classify as moderate inflammation. As the vessels becoming more prominent  and proliferated, literally the appendix becomes congested, with the change in the diameter and the consistency of the organ, the surgeon defines it as severe inflammation of the appendix. Gangrenous appendix defines itself, and if there is puss or fibrin deposition, the condition is called suppurated appendicitis. When the organ is perforated, it is called perforated appendicitis, though it can either accompanied by peritonitis or not.
We did also include the histopathological examination result of the removed appendix from the pathologists’ reports in our data base. Pathologists’ diagnoses were classified according to their reports as acute appendicitis, normal finding, and other diagnoses.

Statistical Analysis
Then we compared the results in each group, surgeons’   and   pathologists’  diagnoses   together. The Statistical Package for Social Sciences, SPSS for Microsoft Windows, version 19.0 (SPSS Inc., Chicago, IL) was used  for  data analysis. Descriptive results are presented  as mean ± standard for 95% confidence interval (CI) or proportions wherever suitable.

Results
A total of 342 patients met the inclusion criteria. Among them, 67% (n=229)  were males, and  33% (n=113) were females, with the mean age of 16.02 ± 9.89 (ranging from 3 to 76) years. Also, 2.6% (n=9) of all patients were under 5 years, 17% (n=58) were in the group of 5-9 years, 36.3% (n=124) were 16-59 years and 0.6% (n=2) has more than 60 years. The largest group was 10-15 years with 43.6% (n=149)  in which 70.5% (n=105)  and 29.5% (n=44) were male and female respectively. From  the 342  patients who underwent open appendectomy, 97.4% (n=333)  were found to have acute appendicitis in the sight of the surgeon in the OR, and the remaining were diagnosed normal  (3, 0.9%) or other pathologies (6, 1.8%). However, 79.5% (n=272) of cases showed findings in favor of acute appendicitis in their histopathological examination performed   on   the   removed  appendix   after  the surgery, and 20.5% (n=70)  didn’t meet the criteria for pathological confirmation of acute appendicitis. This means that the rate of negative appendectomy

in the present study was 20.5%, 16.2% for males and 29.2% for females. Also, the negative appendectomy rates  were  22.2%, 17.2%, 24.8%, and  16.9%  for patients <5 years, 5-9 years, 10-15 years and 16-59 years respectively, while it was zero for patients older than 60 years, though there were only 2 patients in this group (Table 1).

Table 1. Comparison of the surgical findings with histopathology results in different genders and age groups.

 

Histopathology Findings

 

Total

Acute Appendicitis

Normal Findings

Other Pathologies

 

Surgical Findings

Acute Appendicitis (%)

271 (79.2%)

8 (2.3%)

54 (15.8%)

333 (97.4%)

Male (%)

192 (56.1%)

5 (1.5%)

29 (8.5%)

226 (66.1%)

Female (%)

79 (23.1%)

3 (0.9%)

25 (7.3%)

107 (31.3%)

< 5 years (%)

7 (2.1%)

0

2 (0.6%)

9 (2.6%)

5 – 9 years (%)

48 (14%)

1 (0.3%)

9 (2.6%)

58 (17%)

10 – 15 years (%)

111 (32.5%)

3 (0.9%)

29 (8.5%)

143 (41.8%)

16 – 59 years (%)

103 (30.1%)

4 (1.2%)

14 (4.1%)

121 (35.4%)

≥ 60 years (%)

2 (0.6%)

0

0

2 (0.6%)

Normal Findings (%)

0

2 (0.6%)

1 (0.3%)

3 (0.9%)

Male (%)

0

2 (0.6%)

0

2 (0.6%)

Female (%)

0

0

1 (0.3%)

1 (0.3%)

< 5 years (%)

0

0

0

0

5 – 9 years (%)

0

0

0

0

10 – 15 years (%)

0

1 (0.3%)

1 (0.3%)

2 (0.6%)

16 – 59 years (%)

0

1 (0.3%)

0

1 (0.3%)

≥ 60 years (%)

0

0

0

0

Other Pathologies (%)

1 (0.3%)

0

5 (1.5%)

6 (1.8%)

Male (%)

0

0

1 (0.3%)

1 (0.3%)

Female (%)

1 (0.3%)

0

4 (1.2%)

5 (1.5%)

< 5 years (%)

0

0

0

0

5 – 9 years (%)

0

0

0

0

10 – 15 years (%)

1 (0.3%)

0

3 (0.9%)

4 (1.2%)

16 – 59 years (%)

0

0

2 (0.6%)

2 (0.6%)

≥ 60 years (%)

0

0

0

0

           Total (%)

272 (79.5%)

10 (2.9%)

60 (17.5%)

342

 

According to the operation notes, and based on the classification method  used by the surgeons, 29.5% (n=101)  of 342 patients  had  severe inflammation, 26.6% (n=91)  had suppurated  appendicitis, 14.6% (n=50)  were  reported  to  have  locally perforated appendicitis, 10.2% (n=35)  were classified in moderate inflammation, 9.4% (n=32) had gangrenous appendicitis, 5.6% (n=19) were with mild inflammation and 1.5% (n=5) were reported as perforated appendicitis accompanied by peritonitis. Surgeons reported  1.8% (n=6)  of patients to have pathologies other than appendicitis, and only 0.9% (n=3) found to be normal as in their operation note (Figure1).

Fig. 1. Intraoperative findings of acute appendicitis classified by the surgeons.


In   patients   with   severe  inflammation,   78.9% (n=79)   were  confirmed   to   have appendicitis by the  pathologists, same  as 96.7% (n=88)  of  those with   suppurated  appendicitis. All  the   patients with gangrenous appendicitis, locally perforated appendicitis,  and  perforated  appendicitis accompanied by peritonitis also had acute appendicitis in their histopathology reports. However, 34.3% (n=12) and 26.3% (n=5) of the patients with moderate and mild inflammation respectively, found to  have acute appendicitis  in  their  histopathology examination. Only one of patients (16.7%) who were reported as other diagnosis by the surgeon had acute appendicitis in the view of pathologist, while none of those with normal  findings in surgery reported as acute appendicitis after their specimen examined. Distribution through different  genders  and   age groups are shown in table 2 and table 3 respectively (Table 2 and 3).

Table 2. Comparison of the surgeons’ intra-operative findings with the histopathological results in different genders.

 

Histopathological Findings

 

Total

Acute Appendicitis

Normal Findings

Other Pathologies

 

Surgeons’ Classification Method Findings

Severe Inflammation (%)

79 (23.1%)

1 (0.3%)

21 (6.1%)

101 (29.5%)

Male (%)

56 (16.4%)

1 (0.3%)

11 (3.2%)

68 (19.9%)

Female (%)

23 (6.7%)

0

10 (2.9%)

33 (9.6%)

Moderate Inflammation (%)

12 (3.5%)

5 (1.5%)

18 (5.3%)

35 (10.2%)

Male (%)

9 (2.6%)

3 (0.9%)

10 (2.9%)

22 (6.4%)

Female (%)

3 (0.9%)

2 (0.6%)

8 (2.3%)

13 (3.8%)

Mild Inflammation (%)

5 (1.5%)

2 (0.6%)

12 (3.5%)

19 (5.6%)

Male (%)

3 (0.9%)

1 (0.3%)

6 (1.8%)

10 (2.9%)

Female (%)

2 (0.6%)

1 (0.3%)

6 (1.8%)

9 (2.6%)

Suppurated Appendicitis (%)

88 (25.7%)

0

3 (0.9%)

91 (26.6%)

Male (%)

65 (19%)

0

2 (0.6%)

67 (19.6%)

Female (%)

23 (6.7%)

0

1 (0.3%)

24 (7%)

Gangrenous Appendicitis (%)

32 (9.4%)

0

0

32 (9.4%)

Male (%)

21 (6.1%)

0

0

21 (6.1%)

Female (%)

11 (3.2%)

0

0

11 (3.2%)

Perforated Appendicitis (%)

50 (14.6%)

0

0

50 (14.6%)

Male (%)

33 (9.6%)

0

0

33 (9.6%)

Female (%)

17 (5%)

0

0

17 (5%)

Perforated Appendicitis with Peritonitis (%)

5 (1.5%)

0

0

5 (1.5%)

Male (%)

5 (1.5%)

0

0

5 (1.5%)

Female (%)

0

0

0

0

Normal Findings (%)

0

2 (0.6%)

1 (0.3%)

3 (0.9%)

Other Pathologies (%)

1 (0.3%)

0

5 (1.5%)

6 (1.8%)

Total (%)

272 (79.5%)

10 (2.9%)

60 (17.5%)

342

 

Table 3. Comparison of the surgeons’classification method findings with histopathological results in different age groups.

 

Histopathological Findings

 

Total

Acute Appendicitis

Normal Findings

Other Pathologies

 

Surgeons’ Classification Method Findings

Severe Inflammation (%)

79 (23.1%)

1 (0.3%)

21 (6.1%)

101 (29.5%)

< 5 years (%)

1 (0.3%)

0

1 (0.3%)

2 (0.6%)

5 – 9 years (%)

13 (3.8%)

0

2 (0.6%)

15 (4.9%)

10 – 15 years (%)

30 (8.7%)

0

10 (2.9%)

40 (11.7%)

16 – 59 years (%)

35 (10.2%)

1 (0.3%)

8 (2.3%)

44 (12.9%)

≥ 60 years (%)

0

0

0

0

Moderate Inflammation (%)

12 (3.5%)

5 (1.5%)

18 (5.3%)

35 (10.2%)

< 5 years (%)

0

0

1 (0.3%)

1 (0.3%)

5 – 9 years (%)

2 (0.6%)

1 (0.3%)

4 (1.2%)

7 (2%)

10 – 15 years (%)

6 (1.8%)

3 (0.9%)

11 (3.2%)

20 (5.9%)

16 – 59 years (%)

4 (1.2%)

1 (0.3%)

2 (0.6%)

7 (2%)

≥ 60 years (%)

0

0

0

0

Mild Inflammation (%)

5 (1.5%)

2 (0.6%)

12 (3.5%)

19 (5.6%)

< 5 years (%)

0

0

0

0

5 – 9 years (%)

1 (0.3%)

0

3 (0.9%)

4 91.2%)

10 – 15 years (%)

1 (0.3%)

0

7 (2%)

8 (2.3%)

16 – 59 years (%)

3 (0.9%)

2 (0.6%)

2 (0.6%)

7 (2%)

≥ 60 years (%)

0

0

0

0

Suppurated Appendicitis (%)

88 (25.7%)

0

3 (0.9%)

91 (26.6%)

< 5 years (%)

2 (0.6%)

0

0

2 (0.6%)

5 – 9 years (%)

11 (3.2%)

0

0

11 (3.2%)

10 – 15 years (%)

41 (11.9%)

0

1 (0.3%)

42 (12.3%)

16 – 59 years (%)

33 (9.7%)

0

2 (0.6%)

35 (10.2%)

≥ 60 years (%)

1 (0.3%)

0

0

1 (0.3%)

Gangrenous Appendicitis (%)

32 (9.4%)

0

0

32 (9.4%)

< 5 years (%)

2 (0.6%)

0

0

2 (0.6%)

5 – 9 years (%)

3 (0.9%)

0

0

3 (0.9%)

10 – 15 years (%)

13 (3.8%)

0

0

13 (3.8%)

16 – 59 years (%)

14 (4.1%)

0

0

14 (4.1%)

≥ 60 years (%)

0

0

0

0

Perforated Appendicitis (%)

50 (14.6%)

0

0

50 (14.6%)

< 5 years (%)

1 (0.3%)

0

0

1 (0.3%)

5 – 9 years (%)

17 (4.9%)

0

0

17 (4.9%)

10 – 15 years (%)

18 (5.3%)

0

0

18 (5.3%)

16 – 59 years (%)

13 (3.8%)

0

0

13 (3.8%)

≥ 60 years (%)

1 (0.3%)

0

0

1 (0.3%)

Perforated Appendicitis  with
Peritonitis (%)

5 (1.5%)

0

0

5 (1.5%)

< 5 years (%)

1 (0.3%)

0

0

1 (0.3%)

5 – 9 years (%)

1 (0.3%)

0

0

1 (0.3%)

10 – 15 years (%)

2 (0.6%)

0

0

2 (0.6%)

16 – 59 years (%)

1 (0.3%)

0

0

1 (0.3%)

≥ 60 years (%)

0

0

0

0

Normal Findings (%)

0

2 (0.6%)

1 (0.3%)

3 (0.9%)

Other Pathologies (%)

1 (0.3%)

0

5 (1.5%)

6 (1.8%)

              Total (%)

272 (79.5%)

10 (2.9%)

60 (17.5%)

342

 

Discussion
The aim of present study was to evaluate the accuracy of intraoperation  diagnosis made by surgeons according to the method they used in the OR to classify the appendicitis based on their gross observation in Namazee hospital, southern  Iran. In our study, males were almost as twice as females (67% vs. 33%), with the male to female incidence ratio of 2:1, in contrast with some studies [7,17,18] although it is variably reported in different studies, with a peak in patients aged between 10 to 16, in concordance with Memon et al. and Limpawattanisiri et al., [9,19] The rate of negative appendectomy in our study was 20.5%, which was higher among women than men (29.2% vs. 16.2%), whereas Flum et al. reported lower negative appendectomy rates, 15.3% overall, 22.2% in females and 9.3% in males. Also patients aged 10-15 years have the higher rate of negative appendectomy (24.8%) in compare with others, while the rate was zero in patients older than 60 years, in contrast with other studies [12,13], however, we had only two patients older than 60 years, hence we cannot rely on this one completely. The higher rate of negative appendectomy in our center in compare with other studies may be due to lack of diagnostic modalities such as CT scanners, which are not routinely used for diagnosing acute appendicitis in our center, surgeons’ skill, and  high amount  of work in the emergency department of Nemazee hospital.
According to the Table 1, the accuracy of surgeons’ intraoperative  diagnosis  whether it  was an  acute appendicitis or  not  is 81.6%, 85.2% in males and 72.6% in females, telling us the method used by our surgeons is more efficient in men than women. On the other hand, the accuracy in different age groups was 77.8%, 82.8%, 77.9% and  85.5% for patients under 5 years, 5-9 years, 10-15 years and 16-59 years respectively. Since we had  only  2  cases above 60 years, the 100% accuracy rate may not be thoroughly reliable.
According to the Table 2, in patients with severe inflammation in their operation notes, about 20% of them had pathologies other than acute appendicitis. This rate increases in moderate  inflammation  and mild  inflammation  too,  with  approximately  50% and 63% respectively. When we looked back in the patients’ medical files and their pathology reports, we found that follicular hyperplasia of mesenteric lymph nodes was diagnosed for almost all of them, all of those with severe inflammation, 83% of those with moderate inflammation and 92% of patients with mild inflammation. This meanswhile surgeons classified the appendix as an inflamed organ, histopathology examination revealed other   disease,  mesenteric   lymphadenopathy, in
14.1% of the cases. Mesentric lymphadenopathy is one of the important differential diagnoses of  acute appendicitis in  children, and  alongside with acute pelvic inflammatory disease, twisted ovarian cyst or ruptured  graafian follicle, and acute gastroenteritis contribute  more  than  75% of  the  cases with  the mesenteric lymphadenopathy  at the  top. [5,20-22] This condition was seen slightly more in men than women in our study, (27 vs. 26 patients) with peak in patients 10-15 years (29 cases).
All the patients whom surgeons observed gangrenous appendicitis, perforated appendicitis, and perforated appendicitis with peritonitis during their operation, and 96.7% of those with suppurated appendicitis, were confirmed to have acute     appendicitis by pathologists, which  tells us  that  the  method  our surgeons used was more  effective in these specific conditions. Nevertheless, the classification of severe, moderate    and mild inflammation by surgeons has lower efficiency, as the positive predictive value rates were 78.2%,   34.3%   and    26.3%   respectively.  This is  especially true  in  patients  10  to  15  years. In Monajemzadeh  et al. study, the  rate  of confirmed appendicitis by pathologic examination among those who had inflammation in their surgical finding was higher, approximately 100% although they studied children under 15 years [16]. Although in their study, 25.5% of appendices which seemed grossly normal during the operation, found  to  be  abnormal  in pathologic  examination [16], in our study, only 3cases (0.9%) were reported normal in their operation notes, while none of them had histopathological evidence of appendicitis. And finally, from those who seemed to have pathologies other than appendicitis (1.8%), only one patient had acute appendicitis according to the pathology report. We conclude that  although  surgeons’ observation during  the operation  may  be  close to  what  the pathologists see during histopathological examination of the specimens, it may also be very different in some cases. Hence,  routine  histopathology  examination remains the gold standard method for confirming the primary diagnosis of acute appendicitis. Secondly, we came to conclusion that the negative appendectomy rate is considerably affected by age and gender, and despite the advancements in medical diagnosis, it still plays a significant role in the outcome of the patients undergoing open appendectomy.

Conflicts of Interest: None declared.

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References

1. Samelson SL, Reyes HM. Management of perforated appendicitis in children--revisited. Arch Surg 1987;122(6):691-6.
2.   Paydar S,  Shokrollahi S,  Jahanabadi S, Ghaffarpasand F, Malekmohammadi Z, Akbarzadeh A, et al. Emergency Operating Room Workload Pattern: A Single Center Experience from Southern Iran. Bull Emerg Trauma 2013;1(1):38-42.
3. A sound approach to the diagnosis of acute appendicitis. Lancet 1987;1(8526):198-200.
4. Malik AA, Bari SU. Conservative management of acute appendicitis. J Gastrointest Surg 2009;13(5):966-70.
5. Schwartz SI, Brunicardi FC. Schwartz's principles of surgery. 9th ed. New York: McGraw- Hill, Medical Pub, Division, 2010; p.1075.
6. Paydar S, Akbarzadeh A, Manafi AR, Ghaffarpasand F. Short-term outcome of open appendectomy in southern Iran: a single center experience. Bull Emerg Trauma 2013;1(3):123-6.
7. Addiss DG, Shaffer N, Fowler BS, Tauxe RV. The epidemiology of appendicitis and appendectomy in the United States. Am J Epidemiol 1990;132(5):910-25.
8. Yilmaz M, Akbulut S, Kutluturk K, Sahin N, Arabaci E, Ara C, et al. Unusual histopathological findings in appendectomyspecimens from patients with suspected acute appendicitis. World J Gastroenterol 2013;19(25):4015-22.
9.  Memon ZA, Irfan S, Fatima K, Iqbal MS, Sami W. Acute appendicitis: diagnostic accuracy of Alvarado scoring system. Asian J Surg 2013;36(4):144-9.
10. Riber C, Tønnesen H, Aru A, Bjerregaard B. Observer variation in the assessment of the histopathologicdiagnosis of acute appendicitis. Scand J Gastroenterol 1999;34(1):46-9.
11. Marudanayagam R, Williams GT, Rees BI. Review of the pathological results of 2660 appendicectomy specimens. J Gastroenterol 2006;41(8):745-9.
12. Flum DR, Koepsell T. The clinical and economic correlates of misdiagnosed appendicitis: nationwide analysis. Arch Surg 2002;137(7):799-804; discussion 804.
13.  Flum DR, Morris A, Koepsell T, Dellinger EP.  Has misdiagnosis of appendicitis decreased over time? A population-based analysis. JAMA 2001;286(14):1748-53.
14. Colson M, Skinner KA, Dunnington G. High negative appendectomy rates are no longer acceptable. Am J Surg 1997;174(6):723-6; discussion 726-7.
15.  Ponsky TA, Hafi M, Heiss K, Dinsmore J, Newman KD, Gilbert J. Interobserver variation in the assessment of appendiceal perforation. J Laparoendosc Adv Surg Tech A 2009;19 Suppl 1:S15-8.
16. Monajemzadeh M, Hagghi-Ashtiani MT, Montaser-Kouhsari L, Ahmadi H, Zargoosh H, Kalantari M. Pathologic evaluation of appendectomy specimens in children: is routine histopatholgic examination indicated? Iran J Pediatr 2011;21(4):485-90.
17. Khan I, ur Rehman A. Application of Alvarado scoring system indiagnosis of acute appendicitis. J Ayub Med Coll Abbottabad 2005;17(3):41-4.
18. Chan MYP, Tan C, Chiu MT, Ng YY. Alvarado score: an admission criterion in patients with right iliac fossa pain. The Surgeon 2003;1(1):39-41.
19. Limpawattanasiri C. Alvarado score for the acute appendicitisin a provincial hospital. J Med Assoc Thai 2011;94(4):441-9.
20. Bongard F, Landers DV, Lewis F.  Differential diagnosis of appendicitis and pelvic inflammatory disease. A prospective analysis. Am J Surg 1985;150(1):90-6.
21. Knight PJ, Vassy LE.  Specific diseases mimicking appendicitis in childhood. Arch Surg 1981;116(6):744-6.
22. McDonald JC. Nonspecific mesenteric lymphadenitis. Surg Gynecol Obstet 1963;116:409.

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Journal compilation © 2014 Trauma Research Center, Shiraz University of Medical Sciences