Is there a role for abdominal computed tomographic scans in appendicitis?

Elevated total and direct bilirubin are associated with acute complicated appendicitis: a single-center based study in Saudi Arabia

BACKGROUND

Appendicitis is the most common abdominal surgical emergency and up to our knowledge no previous studies have been conducted in Saudi Arabia particularly at Qassim region and this study aimed to determine a total and direct bilirubin as a predictor of acute complicated appendicitis.

METHODS

Observational retrospective study that included patients admitted under the general surgery department with a diagnosis of acute appendicitis at King Saud Hospital, Unaizah, Saudi Arabia. Data on age, gender, BMI, diabetes mellitus, total and direct bilirubin, AST, ALT, sodium, and WBCs levels were obtained.

RESULT

Among the overall study population of 158 patients, the age median [IQR] was 24.5 [19-31], males were 99 (62.7%), and complicated appendicitis was 33 (20.9%). The multivariable analysis revealed that both elevated total and direct bilirubin are associated with complicated appendicitis (aOR = 3.79, 95% CI: 1.67-8.48, P = 0.001) and (aOR = 4.74, 95% CI: 2.07-10.86, P < 0.001) respectively. A receiver operating characteristic curve showed the best cutoff value of total and direct bilirubin as ≥ 15 µmol/L and ≥ 5 µmol/L respectively, with a sensitivity of 57.6%, and specificity of 73.6% for elevated total bilirubin, and a sensitivity of 54.6%, and specificity of 80% for elevated direct bilirubin.

CONCLUSION

Elevated total and direct bilirubin are associated with acute complicated appendicitis in this setting. However, it should be supportive factor for acute complicated appendicitis and not considered as standalone diagnostic test.

Hospitalization Trends for Acute Appendicitis in Spain, 1998 to 2017

The incidence of acute appendicitis decreased in Western countries from 1930 to at least the early 1990s, when epidemiological data started becoming scarcer. This study aimed to assess the trend in annual hospitalizations for acute appendicitis in all people Spain for a 20-year period between 1998 and 2017. This observational study analyzing direct age-standardized hospital admission rates by gender and age group (0–14 years, 15–34 years, 35–44 years, 45–64 years, and ≥65 years). Joinpoint regression models were fitted to evaluate changes in trends. There were 789,533 emergency hospital admissions for acute appendicitis between 1998 and 2017: 58.9% in boys and men and 41.1% in girls and women. Overall, there was a significant increase in admissions for this cause from 1998 to 2009, with an annual percent change (APC) of 0.6%. Following the peak in 2009, admission rates decreased by around 1.0% annually until 2017. The length of hospital stay gradually decreased from 4.5 days in 1998 to 3.4 days in 2017. The trends in hospital admissions for acute appendicitis in Spain changed over the study period, decreasing from 2009, especially in people younger than 35 years.

[Can Uncomplicated Adult Appendicitis Also Be Treated Conservatively?]

Can Uncomplicated Adult Appendicitis Also Be Treated Conservatively? Abstract. For more than a century, appendectomy has been the first-line treatment for acute appendicitis. Despite modern imaging, it is not an easy disease to diagnose and is one of the most common emergency procedures worldwide. Conservative therapy for uncomplicated adult appendicitis is increasingly becoming the focus of discussion. Due to current data, a recommendation for conservative therapy of uncomplicated adult appendicitis can not be given. For the time being it should be reserved for a selected patient group.

Retrospective cohort study on clinical predictors for acute abnormalities on CT scan in adult patients with abdominal pain

PURPOSE

Identification of clinical predictors of acute and surgical pathologies on abdominal CT in patients with non-traumatic abdominal pain (NTAP).

METHODS

Retrospective chart review cohort study of adults who had abdominal CT scans for investigation of NTAP in the Emergency Department in a tertiary care center in Lebanon. Multivariate analyses were performed to identify predictors of pathologies on CT scan.

RESULTS

This study included 147 patients who had abdominal CT scans for NTAP. Mean age was 39.8 ± 15.1 years and 58.5 % of patients were females. Less than half (44.9 %) had normal scans. Women had significantly higher rates of normal scans compared to males. Right lower quadrant (RLQ) tenderness was associated with significantly higher odds of having acute abnormalities on CT and of having surgical diagnoses, while epigastric tenderness was negatively associated with these two outcomes. Right and left upper quadrants and diffuse abdominal tenderness, and an abnormal neutrophil count were found to be associated with surgical diagnoses on CT.

CONCLUSIONS

Women are less likely to have acute and surgical pathologies on CT ordered for non traumatic abdominal pain. Epigastric tenderness is negatively associated with abnormal and surgical CT results while RLQ tenderness is associated with an abnormal CT that is likely surgical in nature. These findings should help improve diagnostic accuracy of ordering providers and improve resource utilization.

Computed tomography for diagnosis of acute appendicitis in adults

BACKGROUND

Diagnosing acute appendicitis (appendicitis) based on clinical evaluation, blood testing, and urinalysis can be difficult. Therefore, in persons with suspected appendicitis, abdominopelvic computed tomography (CT) is often used as an add-on test following the initial evaluation to reduce remaining diagnostic uncertainty. The aim of using CT is to assist the clinician in discriminating between persons who need surgery with appendicectomy and persons who do not.

OBJECTIVES

Primary objective Our primary objective was to evaluate the accuracy of CT for diagnosing appendicitis in adults with suspected appendicitis. Secondary objectives Our secondary objectives were to compare the accuracy of contrast-enhanced versus non-contrast-enhanced CT, to compare the accuracy of low-dose versus standard-dose CT, and to explore the influence of CT-scanner generation, radiologist experience, degree of clinical suspicion of appendicitis, and aspects of methodological quality on diagnostic accuracy.

SEARCH METHODS

We searched MEDLINE, Embase, and Science Citation Index until 16 June 2017. We also searched references lists. We did not exclude studies on the basis of language or publication status.

SELECTION CRITERIA

We included prospective studies that compared results of CT versus outcomes of a reference standard in adults (> 14 years of age) with suspected appendicitis. We excluded studies recruiting only pregnant women; studies in persons with abdominal pain at any location and with no particular suspicion of appendicitis; studies in which all participants had undergone ultrasonography (US) before CT and the decision to perform CT depended on the US outcome; studies using a case-control design; studies with fewer than 10 participants; and studies that did not report the numbers of true-positives, false-positives, false-negatives, and true-negatives. Two review authors independently screened and selected studies for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently collected the data from each study and evaluated methodological quality according to the Quality Assessment of Studies of Diagnostic Accuracy - Revised (QUADAS-2) tool. We used the bivariate random-effects model to obtain summary estimates of sensitivity and specificity.

MAIN RESULTS

We identified 64 studies including 71 separate study populations with a total of 10,280 participants (4583 with and 5697 without acute appendicitis). Estimates of sensitivity ranged from 0.72 to 1.0 and estimates of specificity ranged from 0.5 to 1.0 across the 71 study populations. Summary sensitivity was 0.95 (95% confidence interval (CI) 0.93 to 0.96), and summary specificity was 0.94 (95% CI 0.92 to 0.95). At the median prevalence of appendicitis (0.43), the probability of having appendicitis following a positive CT result was 0.92 (95% CI 0.90 to 0.94), and the probability of having appendicitis following a negative CT result was 0.04 (95% CI 0.03 to 0.05). In subgroup analyses according to contrast enhancement, summary sensitivity was higher for CT with intravenous contrast (0.96, 95% CI 0.92 to 0.98), CT with rectal contrast (0.97, 95% CI 0.93 to 0.99), and CT with intravenous and oral contrast enhancement (0.96, 95% CI 0.93 to 0.98) than for unenhanced CT (0.91, 95% CI 0.87 to 0.93). Summary sensitivity of CT with oral contrast enhancement (0.89, 95% CI 0.81 to 0.94) and unenhanced CT was similar. Results show practically no differences in summary specificity, which varied from 0.93 (95% CI 0.90 to 0.95) to 0.95 (95% CI 0.90 to 0.98) between subgroups. Summary sensitivity for low-dose CT (0.94, 95% 0.90 to 0.97) was similar to summary sensitivity for standard-dose or unspecified-dose CT (0.95, 95% 0.93 to 0.96); summary specificity did not differ between low-dose and standard-dose or unspecified-dose CT. No studies had high methodological quality as evaluated by the QUADAS-2 tool. Major methodological problems were poor reference standards and partial verification primarily due to inadequate and incomplete follow-up in persons who did not have surgery.

AUTHORS' CONCLUSIONS

The sensitivity and specificity of CT for diagnosing appendicitis in adults are high. Unenhanced standard-dose CT appears to have lower sensitivity than standard-dose CT with intravenous, rectal, or oral and intravenous contrast enhancement. Use of different types of contrast enhancement or no enhancement does not appear to affect specificity. Differences in sensitivity and specificity between low-dose and standard-dose CT appear to be negligible. The results of this review should be interpreted with caution for two reasons. First, these results are based on studies of low methodological quality. Second, the comparisons between types of contrast enhancement and radiation dose may be unreliable because they are based on indirect comparisons that may be confounded by other factors.

A Prospective Study on the Diagnostic Value of Hyperbilirubinemia as a Predictive Factor for Appendicular Perforation in Acute Appendicitis

Background

Appendicitis is one of the most common surgical emergency in general surgical practices. Early and prompt diagnosis is necessary to avoid life-threatening complications associated with it. The diagnosis is mainly clinically aided by imaging techniques. The physiological obstruction of the bile flow associated with appendicular pathology leads to hyperbilirubinemia, which can be used as a predictive factor of appendicular perforation.

Method

This prospective study was conducted in the department of general surgery in Madras Medical College and Rajiv Gandhi Government Hospital, Chennai, from January 2012 to November 2012. A total of 378 patients with the features of acute appendicitis or appendicular perforation admitted in the emergency surgical ward were included.

Results

Out of 378 of the study population, 18% had appendicular perforation and 82% had acute appendicitis. Out of 67 perforations, 60 patients have hyperbilirubinemia (90%) whereas out of 311 patients with appendicitis, only 89 (29%) of them had elevated bilirubin. Hyperbilirubinemia with a cutoff point of 0.9 mg% for appendicitis patients has a sensitivity of 89.6%, specificity of 71.4%, a positive predictive value of 27%, and a negative predictive value of 96.9%. Hyperbilirubinemia with a cutoff point of >1.3 mg% for appendicular perforation has a sensitivity of 80%, specificity of 89%, a positive predictive value of 93%, and a negative predictive value of 96%.

Conclusions

Hyperbilirubinemia with bilirubin levels more than 1.3 mg% are highly predictive of appendicular perforation and, hence, aid in prompt diagnosis. This can be combined with a clinical diagnosis and imaging for an accurate and precise diagnosis.

Trends in diagnostic approaches for pediatric appendicitis: nationwide population-based study

BACKGROUND

To define the benefits of different methods for diagnosis of pediatric appendicitis in Taiwan, a nationwide cohort study was used for analysis.

METHODS

We identified 44,529 patients under 18 years old who had been hospitalized with a diagnosis of acute appendicitis between 2003 and 2012. We analyzed the percentages of cases in which ultrasound (US) and/or computed tomography (CT) were performed and non-perforated and perforated appendicitis were diagnosed for each year. Multivariate logistic regression analyses were performed to evaluate risk factors for perforated appendicitis.

RESULTS

There were more cases of non-perforated appendicitis (N = 32,491) than perforated appendicitis (N = 12,038). The rate of non-perforated cases decreased from 0.068% in 2003 to 0.049% in 2012; perforated cases remained relatively stable at 0.024%~0.023% from 2003 to 2012. The percentage of CT evaluation increased from 3% in 2003 to 20% in 2012; the rates of US or both US and CT evaluations were similar annually. The percentage of neither CT nor US evaluation gradually decreased from 97% in 2003, to 79% in 2012. The odds ratios of a perforated appendix for those patients diagnosed by US, CT, or both US and CT were 1.227 (95% confidence interval (CI) 0.91, 1.65; p = 0.173), 2.744 (95% CI 2.55, 2.95; p < 0.001), and 5.062 (95% CI = 3.14, 8.17; p < 0.001), respectively, compared to patients who did not receive US or CT. The odd ratios of a perforated appendix for those patients 7-12 and ≤6 years old were 1.756 (95% CI 1.67, 1.84; p < 0.001) and 3.094 (95% CI 2.87, 3.34; p < 0.001), respectively, compared to those 13-18 years old.

CONCLUSIONS

Our study demonstrated that using CT scan as a diagnostic tool for acute appendicitis increased annually; most patients especially those ≤6 years old who received CT evaluation had a greater risk of having perforated appendicitis. We recommend a prompt appendectomy in those pediatric patients with typical clinical symptoms and physical findings for non-complicated appendicitis to avoid the risk of appendiceal perforation.

CT differentiation between tubo-ovarian and appendiceal origin of right lower quadrant abscess: CT, clinical, and laboratory correlation

To investigate which clinical, laboratory, and CT findings potentially facilitate the differential diagnosis between tubo-ovarian abscess (TOA) and periappendicular abscess (PAA), we retrospectively reviewed abdominal CT examinations and medical records for all women who presented to our medical center with unilateral right pelvic abscess formation who underwent CT evaluation from 2004-2014. A wide spectrum of clinical data and imaging findings were recorded. CT diagnoses were made in consensus by two experienced body radiologists blinded to the final diagnosis. Findings associated with the infections were compared using the chi-square (χ(2)) or the Fisher exact test. Ninety-one patients were included; 58 with PAA (mean age 46 years) and 33 with TOA (mean age 37 years). Pain on cervical motion (67 %) and vaginal discharge (21 %) were significantly more common in TOA; other clinical signs were similar. The presence of right ovarian vein entering the mass on CT had 100 % specificity and 94 % sensitivity to TOA. Distended right fallopian tube (79 %), mass posterior to mesovarium (76 %), contralateral pelvic fat stranding (55 %), and thickening of sacrouterine ligaments (55 %) were significantly more common in TOA. Positive "arrowhead sign" (91 %), mesenteric lymphadenopathy (85 %), small bowel wall thickening (55 %), fluid in the right paracolic gutter (50 %), and cecal wall thickening (48 %) were significantly more common in PAA;internal gas was revealed only in PAA (33 %). Distinct CT features can increase diagnostic certainty regarding the origin of right lower quadrant abscess in women.

Evaluating the Patient with Right Lower Quadrant Pain

Right lower quadrant pain is one of the most common indications for imaging evaluation of the abdomen in the emergency department setting. This article reviews important imaging findings associated with acute appendicitis as well as major differential considerations including: mesenteric adenitis, Meckel diverticulum, neutropenic colitis, right-sided diverticulitis, epiploic appendagitis, omental infarction, and inflammatory bowel diseaseRight lower quadrant pain is one of the most common indications for imaging evaluation of the abdomen in the emergency department setting. This article reviews important imaging findings associated with acute appendicitis as well as major differential considerations including: mesenteric adenitis, Meckel diverticulum, neutropenic colitis, right-sided diverticulitis, epiploic appendagitis, omental infarction, and inflammatory bowel disease.

Changing roles of computed tomography in diagnosing acute appendicitis in emergency rooms

BACKGROUND

We used the Taiwan National Health Insurance Database for analysis and statistics to investigate the role of computed tomography (CT) in diagnosing acute appendicitis.

MATERIALS AND METHODS

All 10 046 patients with acute appendicitis were selected and categorized into two groups based on those who did and did not receive CT 3 days before acute appendicitis diagnosis: non-CT and CT groups. A noteworthy outcome was the incidence of peritonitis within 90 days after diagnosis of acute appendicitis.

RESULTS

The rate of using CT for patients with acute appendicitis increased considerably from 7.9% to 52.9% from 2000 to 2010. The peritonitis incidence rates were 3.54% and 10.7% in the non-CT and CT groups, respectively. Patients who received CT on the same day exhibited a 3.8-fold higher risk of peritonitis than did those in the non-CT group. Those who underwent CT before diagnosis of acute appendicitis exhibited no significant difference of peritonitis risk when compared with those in the non-CT group. The CT group patients were hospitalized 2.19 days longer than the non-CT group patients. Patients who received CT before and on the same day were hospitalized 1.31 and 2.43 days longer than those who did not undergo CT.

CONCLUSION

Patients who underwent CT exhibited higher risks of peritonitis and longer hospital stays compared with those who did not. Moreover, patients who received CT on the same day of operation exhibited a higher risk of peritonitis than those who underwent CT 1 or 2 days before operation.

The normal appendix on CT: does size matter?

PURPOSE

(1) To evaluate the frequency of visualisation and measurements of the normal appendix. (2) To correlate Body Mass Index (BMI) and gender with visualisation of the normal appendix. (3) To correlate age, gender and body length with appendiceal length.

MATERIALS AND METHODS

A retrospective review of 186 patients undergoing abdominal CT without suspicion of acute appendicitis was done. Frequency of visualisation and measurements (including maximal outer diameter, wall thickness, length, content, location of base and tip) of normal appendices were recorded.

RESULTS

Prevalence of appendectomy was 34.4%. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of visualisation of the normal appendix were 76%, 94%, 96%, 67%, and 82% respectively. The mean maximal diameter of the appendix was 8.19 mm±1.6 (SD) (range, 4.2-12.8 mm). The mean length of the appendix was 81.11 mm±28.44 (SD) (range, 7.2-158.8 mm). The mean wall thickness of the appendix was 2.22 mm±0.56 (SD) (range, 1.15-3.85 mm). The most common location of the appendiceal tip was pelvic in 66% appendices. The most common location of the appendiceal base was inferior, medial, and posterior in 37%. The normal appendix contained high-density material in 2.2%. There was a significant correlation between gender and appendiceal length, with men having longer appendices than women.

CONCLUSION

Most normal appendices are seen at multislice CT using i.v. contrast. The maximal outer diameter of the normal appendix overlaps with values currently used to diagnose appendicitis on CT.

Hyperbilirubinemia is a significant indicator for the severity of acute appendicitis

Purpose

This study aims to reveal more effective clinical or laboratory markers for the diagnosis of acute appendicitis and to score the severity based on a sufficiently large number of patients with acute appendicitis.

Methods

We identified 1,195 patients with acute appendicitis after excluding those with other causes of hyperbilirubinemia among the 1,271 patients that underwent a laparoscopic or an open appendectomy between 2009 and 2010. A retrospective chart review of the medical records, including laboratory and histologic results, was conducted. We then analyzed the data using univariate and multivariate analyses.

Results

Among the 1,195 patients, a laparoscopic appendectomy was performed in 685 cases (57.32%), and an open appendectomy was performed in 510 cases (42.68%). The univariate analysis demonstrated significant differences for white blood cell count (P < 0.0001), segmented neutrophils (P = 0.0035), total bilirubin (P < 0.0001), and systemic inflammatory response syndrome (SIRS) score between groups (P < 0.0001). The multivariate analysis demonstrated that total bilirubin (odds ratio, 1.772; 95% confidence interval, 1.320 to 2.379; P = 0.0001) and SIRS score (odds ratio, 1.583; 95% confidence interval, 1.313 to 1.908; P < 0.0001) have statistically significant diagnostic value for perforated appendicitis.

Conclusion

Hyperbilirubinemia is a statistically significant diagnostic marker for acute appendicitis and the likelihood of perforation.

Alternative diagnoses to suspected appendicitis at CT

PURPOSE

To assess alternative diagnoses in adults undergoing computed tomography (CT) for suspected acute appendicitis in routine clinical practice.

MATERIALS AND METHODS

This retrospective study was HIPAA compliant and institutional review board approved; informed consent was waived. A total of 1571 consecutive adults were referred from emergency department or urgent care settings for evaluation of suspected acute appendicitis at a single academic medical center from January 2006 to December 2009. Diagnoses given by board-certified radiologists at nonfocused abdominopelvic CT and ultimate clinical diagnoses by a combination of clinical, surgical, pathologic, and other radiologic findings were analyzed. Comparisons were made by using the Fisher exact test and Mann-Whitney test, where appropriate, with a two-tailed P value of less than .05 used as the criterion for statistical significance.

RESULTS

A specific diagnosis at CT examination was made in 867 of 1571 (55.2%) patients. Acute appendicitis was favored in 371 of 1571 (23.6%) patients. An alternative diagnosis other than appendicitis was suggested in 496 of 1571 (31.6%) patients. Among patients with an alternative CT diagnosis, 204 of 496 (41.1%) were hospitalized and 109 of 496 (22.0%) underwent surgical or image-guided intervention for diagnoses other than appendicitis, compared with rates of 14.1% and 4.4%, respectively, among patients in whom a specific diagnosis was not made at CT (P < .0001). The most common broad categories of disease included nonappendiceal gastrointestinal conditions (46.0%), gynecologic conditions (21.6%), genitourinary conditions (16.9%), and hepatopancreaticobiliary conditions (7.7%).

CONCLUSION

In adult patients clinically suspected of having acute appendicitis, abdominopelvic CT frequently identifies an alternative cause for symptoms, which often requires hospitalization and surgery for treatment.

Impact of computed tomography of the abdomen on clinical outcomes in patients with acute right lower quadrant pain: a meta-analysis

BACKGROUND

Clinical evaluation alone is still considered adequate by many clinicians who treat patients with appendicitis. The impact of computed tomography (CT) on clinical outcomes remains unclear, and there is no consensus regarding the appropriate use of CT in these patients. We sought to evaluate the impact of abdominal CT on the clinical outcomes of patients presenting with suspected appendicitis.

METHODS

We conducted a systematic review of the literature to identify studies that examined clinical outcomes related to the use of abdominal CT in the diagnosis of acute appendicitis. Inclusion criteria were studies of adult patients with suspected appendicitis that evaluated the impact of abdominal CT on negative appendectomy rates, perforation rates or time to surgery. Two independent investigators reviewed all titles and abstracts and extracted data from 28 full-text articles. Statistical analysis was conducted using Review Manager 5.0.10 software.

RESULTS

The negative appendectomy rate was 8.7% when using CT compared with 16.7% when using clinical evaluation alone (p < 0.001). There was also a significantly lower negative appendectomy rate during the CT era compared with the pre-CT era (10.0% v. 21.5%, p < 0.001). Time to surgery was evaluated in 10 of the 28 studies, 5 of which demonstrated a significant increase in the time to surgery with the use of CT. Appendiceal perforation rates were unchanged by the use of CT (23.4% in the CT group v. 16.7% in the clinical evaluation group, p = 0.15). Similarly, the perforation rate during the CT era was not significantly different than that during the pre-CT era (20.0% v. 19.6%, p = 0.74).

CONCLUSION

This meta-analysis supports the hypothesis that the use of preoperative abdominal CT is associated with lower negative appendectomy rates. The use of CT in the absence of an expedited imaging protocol may delay surgery, but this delay is not associated with increased appendiceal perforation rates. Routine CT in all patients presenting with suspected appendicitis could reduce the rate of unnecessary surgery without increasing morbidity.

Clinical policy: Critical issues in the evaluation and management of emergency department patients with suspected appendicitis

This clinical policy from the American College of Emergency Physicians is an update of a 2000 clinical policy on the evaluation and management of patients presenting with nontraumatic acute abdominal pain.1 A writing subcommittee reviewed the literature to derive evidence-based recommendations to help clinicians answer the following critical questions: (1)Can clinical findings be used to guide decision making in the risk stratification of patients with possible appendicitis? (2) In adult patients with suspected acute appendicitis who are undergoing a computed tomography scan, what is the role of contrast? (3) In children with suspected acute appendicitis who undergo diagnostic imaging, what are the roles of computed tomography and ultrasound in diagnosing acute appendicitis?Evidence was graded and recommendations were given based on the strength of the available data in the medical literature.

The Use of a Computed Tomography Scan to Rule Out Appendicitis in Women of Childbearing Age is as Accurate as Clinical Examination: A Prospective Randomized Trial

Diagnosing appendicitis continues to be a difficult task for clinicians. The use of routine CT scan has been advocated to improve the accuracy of diagnosing appendicitis. When compared with the use of clinical examination alone, CT scan was not significantly different with regard to making the diagnosis of appendicitis in women of childbearing age. The use of computed tomography in making the diagnosis of appendicitis has become the current standard of practice in most emergency rooms. In women of childbearing age, with possible appendicitis, we prospectively compared clinical observation alone (OBS) to appendiceal CT scan with clinical observation (CT). Ninety women (OBS: 48, CT: 42) with questionable appendicitis and an Alvarado Score ranging from two to eight were prospectively randomized. A true positive study/exam resulted in a laparotomy that revealed a lesion requiring operation (confirmed by pathology). A true negative exam/study did not require operation. Hospital stay (OBS = 1.9 ± 1.6 vs CT = 1.3 ± 1.4 days) and charges (OBS = $9,459 ± 7,358 vs CT = $9,443 ± 8,773) were similar. The OBS group had an accuracy of 93 per cent, sensitivity of 100 per cent, and a specificity of 87.5 per cent. The CT group had an accuracy of 93 per cent, sensitivity of 89.5 per cent, and specificity of 95.6 per cent. Although this study is too small to statistically establish equivalence, the data suggest that a CT scan reliably identifies women who need an operation for appendicitis and seems to be as good as clinical examination.

CT scan in patients with suspected appendicitis: clinical implications for the acute care surgeon

OBJECTIVE

To determine the influence of computed tomography (CT) scans on diagnosis and management of patients with suspected appendicitis.

METHODS

Retrospective 2-year review of 1,630 patients with suspected appendicitis, categorized into three groups based on the likelihood (Alvarado scores) of having appendicitis. Group 1: low likelihood (Alvarado score < or =4); group 2: intermediate likelihood (Alvarado scores 5-7), and group 3: high likelihood (Alvarado score > or = 8). CT scan utilization, hospital course, and final pathology were retrospectively reviewed.

RESULTS

More patients received a CT scan in 2006 as compared with 2005 (60 vs. 52%; p = 0.001). The overall appendectomy rate was similar between the 2 years (57% in 2005 vs. 57% in 2006; p = 0.995). The overall appendectomy rate in patients with a CT was significantly higher as compared with those without (60 vs. 53%; p = 0.002). The appendectomy rate in patients with Alvarado scores < or =4 and no CT scan was significantly lower than in those with a CT scan (12 vs. 48%; p < 0.0001). The overall negative appendectomy rate in patients with a CT scan was similar to that in those without: 31/546 (6%) vs. 23/383 (6%).

CONCLUSIONS

CT scan utilization increased the appendectomy rate only in patients with a low clinical suspicion for appendicitis. Preoperative CT scans did not decrease the negative appendectomy rate.

Abdominal Computed Tomography in the Evaluation of Acute and Perforated Appendicitis in the Community Setting

Several studies report sensitivity and specificity of abdominal computed tomography scans (CT) for the evaluation of acute appendicitis as high as 98 per cent. Despite increased utilization of CT, the rate of negative appendectomy has remained constant at 10 to 20 per cent. The objective of this study was to assess the effectiveness of CT in the evaluation of acute and perforated appendicitis in an academic community-based setting. A retrospective review of 550 patient charts with International Classification of Diseases-9 (ICD-9) codes for acute and perforated appendicitis from January 2002 to October 2005 was performed. Sensitivity of CT was 87 per cent with a positive predictive value of 92 per cent. Specificity was 42 per cent with a negative predictive value of 29 per cent. Negative appendectomy rates were similar with or without CT (11% vs 13%, respectively). Our data suggests that CT used liberally in everyday practice in a community-based setting to evaluate acute appendicitis may not have as strong of a diagnostic value as those used in protocol-driven research studies. Further prospective studies are needed to formulate criteria to better delineate the role of CT in the evaluation of acute appendicitis.

The use of the clinical scoring system by Alvarado in the decision to perform computed tomography for acute appendicitis in the ED

STUDY OBJECTIVE

Appendicitis is part of the differential of an acute abdomen and can be a difficult diagnosis to make. Strategies to suggest which patients presenting to the emergency department (ED) should undergo computed tomography (CT) scan to confirm appendicitis have not been addressed. We develop guidelines for CT scanning based on Alvarado clinical scores for patients with suspected and confirmed cases of appendicitis.

METHODS

A retrospective review of 150 charts of patients aged 7 and older who presented with abdominal pain to the ED of a 392-bed acute care facility over a 6-month period were evaluated by ED physicians and underwent CT to rule out appendicitis. Patient demographics, presenting signs, and symptoms were documented. Using the scoring system for appendicitis, developed by Alvarado, each chart was retrospectively scored. The Alvarado scores were correlated with positive pathology findings, as well as Alvarado scores with a negative CT scan. Equivocal scores, having neither high sensitivity nor specificity for appendicitis were calculated.

RESULTS

Computed tomography scans with Alvarado scores of 3 or lower were performed in 37% (55/150) of patients to rule out appendicitis. The sensitivity of Alvarado scores 3 or lower for not having appendicitis was 96.2% (53/55), and the specificity 67% (2/3). Patients with Alvarado scores 7 or higher had an incidence of acute appendicitis of 77.7% (28/36). The sensitivity of Alvarado scores 7 or higher for appendicitis was 77% (28/36), and the specificity 100% (8/8). The sensitivity of equivocal Alvarado scores, defined as scores of 4 to 6, for acute appendicitis was 35.6% (21/59), and the specificity 94% (36/38). The sensitivity and specificity of CT scans in patients with equivocal Alvarado scores remained high, at 90.4% and 95%, respectively.

CONCLUSIONS

In the equivocal clinical presentation of appendicitis as defined by Alvarado scores of 4 to 6, adjunctive CT is recommended to confirm the diagnosis in the ED setting. If clinical presentation suggests acute appendicitis by an Alvarado score of 7 or higher, surgical consultation is recommended. Computed tomography is not indicated in patients with Alvarado scores of 3 or lower to diagnose acute appendicitis.

Disconnect between incidence of nonperforated and perforated appendicitis: implications for pathophysiology and management

OBJECTIVE

Appendicitis has been declining in frequency for several decades. During the past 10 years, its preoperative diagnosis has been made more reliable by improved computed tomography (CT) imaging. Thresholds for surgical exploration have been lowered by the increased availability of laparoscopic exploration. These innovations should influence the number of appendectomies performed in the United States. We analyzed nationwide hospital discharge data to study the secular trends in appendicitis and appendectomy rates.

METHODS

All appendicitis and appendiceal operations reported to the National Hospital Discharge Survey (NHDS) 1970-2004 were classified as perforated, nonperforated, negative, and incidental appendectomies and analyzed over time and by various demographic measures. Secular trends in the population-based incidence rates of nonperforated and perforated appendicitis and negative and incidental appendectomy were examined.

RESULTS

Nonperforated appendicitis rates decreased between 1970 and 1995 but increased thereafter. The 25-year decreasing trend was accounted for almost entirely by a decreasing incidence in the 10-19 year age group. The rise after 1995 occurred in all age groups above 5 years and paralleled increasing rates of CT imaging and laparoscopic surgery on the appendix. Since 1995 the negative appendectomy rate has been falling, especially in women, and incidental appendectomies, frequent in prior decades, have been rarely performed. Despite these large changes, the rate of perforated appendicitis has increased steadily over the same period. Although perforated and nonperforated appendicitis rates were correlated in men, they were not significantly correlated in women nor were there significant negative correlations between perforated and negative appendectomy rates.

CONCLUSION

The 25-year decline in nonperforated appendicitis and the recent increase in appendectomies coincident with more frequent use of CT imaging and laparoscopic appendectomies did not result in expected decreases in perforation rates. Similarly, time series analysis did not find a significant negative relationship between negative appendectomy and perforation rates. This disconnection of trends suggests that perforated and nonperforated appendicitis may have different pathophysiologies and that nonoperative management with antibiotic therapy may be appropriate for some initially nonperforated cases. Further efforts should be directed at identifying preoperative characteristics associated with nonperforating appendicitis that may eventually allow surgeons to defer operation for those cases of nonperforating appendicitis that have a low perforation risk.

Quelle est l’épaisseur de l’appendice normal au scanner multibarrette ?

OBJECTIVE

To determine the wall thickness and external diameter values of the normal appendix on multidetector computed tomography (MDCT). Materials and methods. A senior radiologist with no knowledge of the patient's surgical history prospectively examined the abdominal-pelvic CT scans of 57 consecutive adult patients with no suspicion for appendicitis. Most of the patients (50/57) received an intravenous iodinated contrast material injection, but none had gastrointestinal studies. All slices (1 and 5 mm) and multiplanar reconstructions were analyzed on a treatment console. The external diameter of the appendix, the thickness of the two appendicular walls, and the presence or absence of intraluminal gas were noted.

RESULTS

The appendix was visualized in 82% of the cases (47/57). The mean external diameter was 6.7 mm+/-1.2 (range, 5.0-11.0 mm). The mean thickness of the two walls was 4.8 mm+/-1.0 (range, 2.6-6.4 mm). Intraluminal air was visualized in 87% of cases (41/47).

CONCLUSION

Contrary to external diameter, the normal thickness of the appendix's two walls does not go beyond the threshold of 6 mm and therefore seems to be a reliable measurement for identifying a normal appendix using MDCT.

Routine versus selective abdominal computed tomography scan in the evaluation of right lower quadrant pain: a randomized controlled trial

OBJECTIVES

To determine the role of abdominal computed tomography (CT) imaging in patients with right lower quadrant (RLQ) pain. The authors hypothesized that selective use of abdominal CT would reduce imaging without increasing the rates of negative appendectomy and perforated appendicitis.

METHODS

A prospective randomized clinical trial was conducted in a community teaching emergency department. Adult patients with acute RLQ abdominal pain with suspected acute appendicitis were included. Patients were randomized to mandatory (all patients) or selective (based on clinical evaluation) abdominal CT imaging. The primary outcome was the negative appendectomy rate.

RESULTS

A total of 152 patients were randomized to selective (n = 80) and mandatory (n = 72) intervention groups. The mean (+/-SD) age was 34.1 (+/-3.5) years, and 48% were female. CT imaging was performed in 54 of 80 patients (68%; 95% confidence interval [CI] = 56% to 78%) in the selective group and in 70 of 72 patients (97%; 95% CI = 90% to 100%) in the mandatory group. There was a trend to a decreased rate of negative appendectomy in the mandatory group (1/39 [2.6%]; 95% CI = 0.5% to 13.2%) as compared with the selective group (6/43 [13.9%]; 95% CI = 6.6% to 27.3%), with a difference in prevalence rates of 11.3% (95% CI = -3.5% to 26.3%). There was also a trend to a decreased perforated appendix rate in the mandatory group (4/39 [10.3%]) as compared with the selective group (7/38 [18.4%]), with a difference in prevalence rates of 8.2% (95% CI = -8.0% to 24.4%).

CONCLUSIONS

In this small sample of adult patients with RLQ abdominal pain and suspected acute appendicitis, CT imaging was performed less frequently in the selective group and there was a trend with mandatory CT imaging to reduced rates of negative appendectomy and perforated appendices.

Computed tomography-based clinical diagnostic pathway for acute appendicitis: prospective validation

BACKGROUND

Despite our regular use of CT for suspected appendicitis, a recent study at our institution demonstrated a negative appendectomy (NA) rate similar to our rate 15 years earlier. Based on analysis of this data, a diagnostic pathway was implemented prospectively for adult patients with possible appendicitis.

STUDY DESIGN

Rates of CT, NA, and perforation for nonpregnant patients over 14 years of age undergoing appendectomy between August 2001 and August 2002 (PRE) were compared with prospectively collected pathway data (PATH, August 2004 to August 2005). All PATH patients were evaluated by a surgeon before CT. All females underwent CT. CT was obtained in male patients with low suspicion or pain for longer than 48 hours. After negative CT, patients were discharged from the emergency department or admitted for observation.

RESULTS

There was a substantial decrease in NA rate after implementation of the pathway (4% PATH [8 of 183] versus 16% PRE [31 of 196], p < 0.001), without a change in the rate of perforation (11% PATH [20 of 175] versus 8% PRE [13 of 165], p = 0.28) or frequency of preoperative CT (59% PATH [108 of 183] versus 60% PRE [118 of 196], p = 0.84).

CONCLUSIONS

Frequent appendiceal CT alone does not ensure surgical diagnostic accuracy. CT need not be used in all patients to achieve very low NA rates. An evidence-based diagnostic algorithm incorporating early surgical evaluation, objective criteria for preoperative CT, deterrence of early operation after negative CT, and use of CT to facilitate safe discharge led to substantial improvements in the care of our adult population presenting with possible appendicitis.

US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta-Analysis

PURPOSE

To perform a meta-analysis to evaluate the diagnostic performance of ultrasonography (US) and computed tomography (CT) for the diagnosis of appendicitis in pediatric and adult populations.

MATERIALS AND METHODS

Medical literature (from 1986 to 2004) was searched for articles on studies that used US, CT, or both as diagnostic tests for appendicitis in children (26 studies, 9356 patients) or adults (31 studies, 4341 patients). Prospective and retrospective studies were included if they separately reported the rate of true-positive, true-negative, false-positive, and false-negative diagnoses of appendicitis from US and CT findings compared with the positive and negative rates of appendicitis at surgery or follow-up. Clinical variables, technical factors, and test performance were extracted. Three readers assessed the quality of studies.

RESULTS

Pooled sensitivity and specificity for diagnosis of appendicitis in children were 88% (95% confidence interval [CI]: 86%, 90%) and 94% (95% CI: 92%, 95%), respectively, for US studies and 94% (95% CI: 92%, 97%) and 95% (95% CI: 94%, 97%), respectively, for CT studies. Pooled sensitivity and specificity for diagnosis in adults were 83% (95% CI: 78%, 87%) and 93% (95% CI: 90%, 96%), respectively, for US studies and 94% (95% CI: 92%, 95%) and 94% (95% CI: 94%, 96%), respectively, for CT studies.

CONCLUSION

From the diagnostic performance perspective, CT had a significantly higher sensitivity than did US in studies of children and adults; from the safety perspective, however, one should consider the radiation associated with CT, especially in children.

Classifying patients suspected of appendicitis with regard to likelihood

BACKGROUND

We sought to develop a clinical predictive model for acute appendicitis and contrast it with current clinical practice.

METHODS

A prospective observational study of patients presenting with signs or symptoms consistent with acute appendicitis. Random-partition modeling was used to develop an appendicitis likelihood model (ALM).

RESULTS

Four hundred thirty-nine patients were enrolled, 101 with appendicitis, and 338 with other diagnoses. The ALM classified patients as "low likelihood" if they had a white blood cell count <9,500 and either no right lower-quadrant tenderness or a neutrophil count <54%. Patients were classified as "high likelihood" if they had a white blood cell count >13,000 with rebound tenderness or both voluntary guarding and neutrophil count >82%. The ALM outperformed actual clinical practice with regard to "missed" appendicitis, negative laparotomies, and total number of imaging studies.

CONCLUSION

The ALM may permit more judicious use of advanced radiographic imaging with lower nontherapeutic laparotomy rates.

Impact of helical computed tomography on the rate of negative appendicitis

OBJECTIVE

To assess the impact of helical computed tomography (HCT) on the rate of negative appendicitis (NA).

METHODS

A before-and-after comparison study comparing data from a prospective consecutive case series to data from a retrospective chart review. The prospective series included all patients presenting to the ED during a 19-month period, during which patients with suspected appendicitis were managed in accordance with a guideline that stipulated HCT in selected cases. The retrospective group included patients taken to the operating room (OR) with a preoperative diagnosis of appendicitis over a 4-year time frame before the use of HCT. The primary outcome variable was the rate of NA.

RESULTS

During the HCT era, 104 of 310 patients, 71 (68%; 95% confidence interval [CI], 59-76) men and 33 (32%; 95% CI, 24-41) women, were taken to the OR with a diagnosis of appendicitis. Fourteen (13.5%; 95% CI, 8-21) were NA. During the pre-HCT period, 445 patients, 280 (62.9%; 95% CI, 58-67) men and 165 (37.1%; 95% CI, 33-42) women were taken to the OR with the preoperative diagnosis of appendicitis, and 66 (14.8%; 95% CI, 12-19) were NA.

CONCLUSION

At the study institution, the selective use of HCT did not result in a significant decline in the rate of NA.

Clinical guidelines, computed tomography scan, and negative appendectomies: a case series

INTRODUCTION

Prior studies suggest that preoperative abdominal computed tomography (CT) scan can contribute to a low negative appendectomy rate. Our study objective was to evaluate cases of negative appendectomies for clinical criteria and CT use.

METHODS

Retrospective 1-year study of all negative appendectomies at a community hospital. Data included clinical evidence for appendicitis as well as CT results if performed.

RESULTS

Of 122 cases reviewed, 8 (6.6%) were negative appendectomies. Six were younger than 20 years. Four had a preoperative CT scan. Overall, 106 (87%) of 122 cases received preoperative CT and had a negative appendectomy rate of 3.8%. Sixteen cases did not have preoperative CT and had a negative appendectomy rate of 25% (odds ratio, 8.5; 95% confidence interval, 1.9-38.5; Fisher exact test P = .01).

CONCLUSION

Patients who had a CT scan for suspected appendicitis had a lower rate of negative appendectomies than those who had no CT. Most of the negative appendectomies occurred in patients younger than 20 years.

Diagnosis of appendicitis with left lower quadrant pain

Abdominal pain is one of the most common chief complaints of patients presenting to the emergency department and, among the diagnoses of abdominal pain, appendicitis is the most common surgical disorder. Traditionally, the diagnosis of appendicitis is based on well-established clinical criteria combined with physician experience. However, appendicitis presenting with rare and misleading left lower quadrant (LLQ) pain may result in an initial false-negative diagnosis by the physician and even result in failure to order the subsidiary examination of computed tomography (CT) or ultrasound, so increasing the risk of perforation/abscess formation and prolonged hospital stay. In this report, we present 2 cases of atypical appendicitis with LLQ pain where the correct diagnosis was not initially considered. One patient had right-sided appendicitis; the inflamed appendix was 12 cm in length and projected into the LLQ. Local peritonitis developed during observation. With the aid of CT, the diagnosis was established in time. The other patient had left-sided appendicitis with situs inversus totalis. Adverse outcomes with appendiceal rupture and abscess formation occurred due to inadvertent physical examinations and inadequate observation. Early clinical suspicion and adequate observation are indicated in patients with uncertain clinical features. However, in patients with unresolved clinical symptoms and/or local peritonitis that develop during observation, imaging studies play a significant role in preoperative diagnosis and determination of proper treatment.

A systematic review of whether oral contrast is necessary for the computed tomography diagnosis of appendicitis in adults

BACKGROUND

There are several methods of contrast administration when performing computed tomography (CT) scanning for suspected appendicitis. In this systematic review we evaluated the diagnostic performance of CT with and without contrast material.

METHODS

Twenty-three reports were identified using a Medline search.

RESULTS

The aggregated diagnostic performance characteristics of all modes of CT scanning were excellent with a range of sensitivity (83--97%), specificity (93--98%), positive predictive value (86--98%), negative predictive value (94--99%), and accuracy (92--97%). The diagnostic performance of CT without oral contrast was similar (sensitivity, 95% vs. 92% [not statistically significant]; negative predictive value, 96% for both protocols) or surprisingly better (specificity, 97% vs. 94%; positive predictive value, 97% vs. 89%; accuracy, 96% vs. 92%; P<.0001) than with oral contrast.

CONCLUSIONS

Noncontrast CT techniques to diagnose appendicitis showed equivalent or better diagnostic performance compared with CT scanning with oral contrast. A prospective comparative trial of CT with and without oral contrast for appendicitis should be performed to assess the adequacy of this modality.

A new approach to accurate diagnosis of acute appendicitis

This study aimed (1) to develop a simple scoring system incorporating ultrasound (US) examination and clinical or laboratory predictors for increasing diagnostic accuracy in acute appendicitis (AA), and (2) to evaluate the performance of the scoring system as compared to that of previous models. Fifteen variables including US assessment for patients admitted with suspected AA were considered in multivariate analysis using the finding of AA at operation as the end point (internal study). The new score, together with 11 previous ones, was applied to a prospective independent population of subjects with suspected AA, and the respective performances were compared (external validation study). Among 303 patients (170 males, mean age 28.3 +/- 13.3 years) of the internal study, 161 went on to surgery, and 130 had AA at operation. Four independent correlates of AA were identified and used for the derivation of the following integer-based scoring system: number of points = 6 for US demonstrating AA + 4 for tenderness in the right lower quadrant + 3 for rebound tenderness + 2 for leukocyte count >12,000/microl. In the external study (201 subjects, 105 males, mean age 28.7 +/- 11.9 years, 109 operated, 87 with AA), when the cut-off of >/or = 8 points for AA was used, sensitivity, specificity, accuracy, and area under the curve of the proposed score were 95.4%, 97.4%, 96.5%, and 93%, respectively, exceeding noticeably the previous models. The proposed scoring system introduces a quantitative combination of the clinical evaluation with US imaging and a marker of inflammatory response, which may enhance the diagnostic accuracy for subjects with suspected AA especially in geographical areas where CT scanning is not readily available on a 24-hour basis.

The Status of Appendiceal CT in an Urban Medical Center 5 Years After Its Introduction: Experience with 753 Patients

OBJECTIVE

Appendiceal CT was introduced at our hospital in 1996 and now is used in most patients. The use of appendiceal CT has generated controversy and mixed results in various investigations. Our purpose was to determine the percentage of patients for whom CT was performed, incidence of appendicitis, accuracy of CT, percentage of equivocal interpretations, and negative appendectomy rates for those patients who did and did not undergo CT.

MATERIALS AND METHODS

Patient records from 2001 that included clinical or CT preoperative examination were analyzed, with follow-up through 2003. Patient age and sex, clinical presentation, CT techniques, CT interpretations, operative reports, pathology reports, and patient disposition were determined. Final diagnoses were provided by pathologic criteria, patient follow-up, or patient survey. Statistical analysis included Fisher's exact test and receiver operating characteristic (ROC) curves.

RESULTS

Of 753 patients, 663 (88%) were examined on CT for suspected appendicitis and 90 had an appendectomy without undergoing CT. The incidence of appendicitis in the patients who underwent CT was 39.2%. The sensitivity and specificity of CT were 99% and 95%, respectively; the area under the ROC curve was 0.9896; and the percentage of equivocal CT interpretations was 3.3%. The false-negative appendectomy rates were 3.0% and 5.6% for patients with and without CT, respectively (for all patients, p = 0.326; for female pediatric patients, p = 0.030).

CONCLUSION

Five years ago, the negative appendectomy rate dropped from 20% to 7%, and it is now 3.0%. The incidence of appendicitis in patients who are examined on CT is stable compared with similar cohorts from prior investigations. Patients who do not undergo CT also have a low negative appendectomy rate, but this relatively small group is selected on the basis of a convincing clinical presentation. Female pediatric patients likely would have a lower negative appendectomy rate with greater use of CT.

Intravenous contrast-enhanced computed tomography in the diagnosis of acute appendicitis

This study evaluated the usefulness of routine, nonfocused intravenous contrast-enhanced computed tomography (CT) in diagnosing acute appendicitis. Also evaluated was the diagnostic value of several findings that were clinically associated with acute appendicitis. Although a number of studies have shown various techniques using CT to be accurate in the diagnosis of acute appendicitis, few studies have focused on CT with using only intravenous contrast material. Computed tomography scan criteria for acute appendicitis have been established chiefly on the basis of appendiceal findings. We, on the other hand, have often observed the following associated conditions during appendectomy: ascites, paresis of the intestine, or thickening of adjacent tissues. In this study, we reviewed the intravenous contrast-enhanced CT scans of 78 patients who had been diagnosed as having acute appendicitis and had subsequently undergone surgery. We also compared the CT scans with patients' surgical and histological findings. As a way of evaluating clinical ancillary signs, we identified and analyzed individual CT findings that included abnormal appendix, calcified appendicolith, ascites, dilated intestine, and cecal wall thickening. The sensitivity, specificity, and accuracy of intravenous contrast-enhanced CT in surgical cases were found to be 91.9%, 87.5%, and 91.0%, respectively. Individual findings except for abnormal appendix were not significantly common among patients who had acute appendicitis. However, more positive findings were observed in patients who had appendicitis than in those who had normal appendixes. Intravenous contrast-enhanced CT scan is a useful technique in the diagnosis of acute appendicitis. The plurality of ancillary signs in CT scans also appears to be a helpful indicator in the diagnosis of acute appendicitis.

Are negative appendectomies still acceptable?

BACKGROUND

The goal was to ascertain if there was a significant change in the negative appendectomy (NA) rate in our community hospital with the increased use of computed tomography (CT).

METHODS

This was a retrospective chart review of all appendectomies for acute disease performed at our institution from January 2000 to December 2002. There is no established protocol; therefore, CT scans were performed at the discretion of the involved physicians. The results of the physical exams, CT scans and pathology were recorded.

RESULTS

Three hundred eighty-nine appendectomies were performed for appendicitis. There was a progressive increase in the use of CT: 52% in 2000, 74% in 2001, and 86% in 2002. There was also a decrease in the NA rate over the 3 years: 17% in 2000, 9% in 2001 and 2% in 2002. The perforated appendicitis rate decreased from 25% in 2000 to 9% in 2002.

CONCLUSION

The appropriate utilization of CT scan as an aid in the diagnosis of acute appendicitis should decrease the NA rate to 2%.

Radiological imaging to improve the emergency department diagnosis of acute appendicitis

OBJECTIVES

To determine the institution's current non-therapeutic (negative) appendicectomy rate; the frequency of clinical predictors for appendicitis in patients who underwent appendicectomy; and the utilization and accuracy of ultrasound scans (USS) and computed tomography (CT) in the diagnosis of appendicitis.

METHODS

A retrospective chart review was conducted in an adult, metropolitan teaching hospital. Patients who presented to the ED and underwent an appendicectomy over a 12-month period were analysed. Symptoms and signs predictive of appendicitis, results of USS and CT scans if performed, and histopathology findings were abstracted from patient records.

RESULTS

Two hundred and forty patients had appendicectomies, 147 (61%) were male and the median age was 25 years (range 14-78 years). The negative appendicectomy rate was 14.3% (95% CI 9.1-21.0%) and 18.3% (95% CI 11.0-26.7%) in males and females, respectively. Abdominal pain shifting to the right iliac fossa (RIF), anorexia and RIF rebound tenderness were found more frequently in patients with positive than negative appendicectomies (P < 0.05). USS and CT scans were performed in 68 (28%) and 15 (9.5%) patients, respectively. The likelihood ratio for appendicitis in patients with a normal USS or a normal CT scan was 0.83 (95% CI 0.56-1.24) and 0.08 (95% CI 0.01-0.60), respectively. There were no false positive CT scan results.

CONCLUSION

Computed tomoraphy scanning should play an increasing role in the ED management of suspected appendicitis. Our negative appendicectomy rate could potentially be halved by the introduction of CT scans in the diagnostic work up of these patients.

A prospective randomized study of clinical assessment versus computed tomography for the diagnosis of acute appendicitis

BACKGROUND

The objective of this study was to determine if routine use of computed tomography (CT) for the diagnosis of appendicitis is warranted.

METHODS

During a one-year study period, all patients who presented to the surgical service with possible appendicitis were studied. One hundred eighty-two patients with possible appendicitis were randomized to clinical assessment (CA) alone, or clinical evaluation and abdominal/pelvic CT. A true-positive case resulted in a laparotomy that revealed a lesion requiring operation. A true-negative case did not require operation at one-week follow-up evaluation. Hospital length of stay, hospital charges, perforation rates, and times to operation were recorded.

RESULTS

The age and gender distributions were similar in both groups. Accuracy was 90% in the CA group and 92% for CT. Sensitivity was 100% for the CA group and 91% for the CT group. Specificity was 73% for CA and 93% for CT. There were no statistically significant differences in hospital length of stay (CA = 2.4 +/- 3.2 days vs. CT = 2.2 +/- 2.2 days, p = 0.55), hospital charges (CA = 10,728 US dollars +/- 10,608 vs. CT = 10,317 US dollars +/- 7,173, p = 0.73) or perforation rates (CA = 6% vs. CT = 9%, p = 0.4). Time to the operating room was shorter in the CA group, 10.6 +/- 8.4 h vs. CT, 19.0 +/- 19.0 h (p < 0.01).

CONCLUSIONS

Clinical assessment unaided by CT reliably identifies patients who need operation for acute appendicitis, and they undergo surgery sooner. Routine use of abdominal/pelvic CT is not warranted. Further research is needed to identify sub-groups of patients who may benefit from CT. Computed tomography should not be considered the standard of care for the diagnosis of appendicitis.

Late abdominal complaints after appendectomy--readmissions during long-term follow-up

BACKGROUND/AIMS

The postoperative risk of small bowel obstruction is a recognized complication following appendectomy. Few studies have reconsidered the whole extent of abdominal complaints and problems following appendectomy. This study tries to evaluate the long-term outcome describing abdominal complaints requiring readmission following appendectomy.

METHODS

A retrospective study of 3,230 patients undergoing open appendectomy at a single center university hospital in Sweden between 1981 and 1996. Late (>30 days) readmissions were noted and the cause for readmission and need for surgical intervention were analyzed.

RESULTS

Overall, late readmissions occurred in 2.94% during a median follow-up of 10 years after appendectomy. Females predominated among those readmitted, as did patients with complicated appendicitis or a 'normal' appendix. Nonspecific abdominal pain with no sign of small bowel obstruction caused almost half of the readmissions (45%). To a large extent this group consisted of females (76%). Small bowel obstruction was seen in 1.24% and was surgically treated in 0.68% of all appendectomies. Incisional hernias were also seen (0.4% of all appendectomies).

CONCLUSION

The magnitude of readmissions due to abdominal complaints is more pronounced than previously reported with as many patients with signs of small bowel obstruction managed nonoperatively as surgically, and frequent readmissions due to nonspecific abdominal pain.

The most useful findings for diagnosing acute appendicitis on contrast-enhanced helical CT

PURPOSE

To evaluate the most useful findings to look for in diagnosing acute appendicitis on contrast-enhanced helical CT.

MATERIAL AND METHODS

Appendiceal helical CT scans with intravenous contrast administration (abdomen, 7-mm collimation; abdominopelvic junction, 5-mm collimation) of 71 patients with surgically proven acute appendicitis and 167 patients with alternative diagnoses were reviewed retrospectively. Three radiologists analyzed the following parameters: enlarged appendix (>6 mm in diameter), appendiceal wall thickening, appendiceal wall enhancement, no identification of the appendix, appendicolith(s), appendiceal intraluminal air, intramural air, extraluminal air, periappendiceal fat stranding, extraluminal fluid, phlegmon, abscess, lymphadenopathy, segmental terminal ileal wall thickening, focal cecal apical thickening, focal colonic wall thickening, and segmental colonic wall thickening. The features that best distinguished appendicitis from alternative diagnoses were selected with stepwise logistic regression analysis.

RESULTS

Nine CT findings distinguished acute appendicitis from alternative diagnoses (P < 0.05): enlarged appendix (R = 0.739), appendiceal wall thickening (R = 0.525), periappendiceal fat stranding (R = 0.414), appendiceal wall enhancement (R = 0.404), focal cecal apical thickening (R = 0.171), appendicolith(s) (R = 0.157), extraluminal air (R = 0.050), intramural air (R = 0.043), and phlegmon (R = 0.030). Enlarged appendix (sensitivity, 93%; specificity, 92%), appendiceal wall thickening (sensitivity, 66%; specificity, 96%), periappendiceal fat stranding (sensitivity, 87%; specificity, 74%), and appendiceal wall enhancement (sensitivity, 75%; specificity, 85%) showed the statistically most significant association with acute appendicitis.

CONCLUSION

On 5-mm-section contrast-enhanced helical CT examinations, enlarged appendix, appendiceal wall thickening, periappendiceal fat stranding, and appendiceal wall enhancement were the most useful findings for diagnosing acute appendicitis.

Implications of removing a normal appendix

BACKGROUND

The diagnosis of acute appendicitis remains difficult and therefore 15-30% of the removed appendices appear to be normal. The aim of this study was to investigate morbidity, mortality and costs of removing a normal appendix in patients with suspected appendicitis.

PATIENTS AND METHODS

Retrospective study of patients who underwent a negative appendectomy for suspected appendicitis in the period 1991-1999 with a median follow-up of 4.4 years. Patients who underwent an elective appendectomy or appendectomy for other reasons were excluded.

RESULTS

In 285 patients (70% women, 30% men) a normal appendix was removed. In 192 (67%) patients a muscle-splitting incision was performed, in 6 (2%) a median laparotomy, and in 51 (18%) the normal appendix was removed by laparoscopy. In 36 patients (13%) a diagnostic laparoscopy was converted to a muscle-splitting incision. Complications occurred in 16 (6%) patients, in 5 (2%) a re-operation was needed. The mean hospital stay was 4.4 (SE 2.8) days, in case of complications 7.4 (SE 4.2) days. The mean extra hospital costs of a negative appendectomy were EUR 2712.

CONCLUSION

The removal of a normal appendix has considerable complications and costs. In an attempt to prevent these costs, extra diagnostic tools should be considered. Expensive diagnostic tools such as diagnostic laparoscopy should be used selectively in order not to further increase costs.

Appendicitis: selective use of abdominal CT reduces negative appendectomy rate

BACKGROUND

Recent literature supports the use of CT for all patients with right lower quadrant pain to improve diagnostic accuracy and reduce hospital cost. Our current practice at a large teaching hospital is to use CT only for patients whose diagnosis remains in question after a thorough history, physical examination, and focused laboratory assessment. In consideration of a more liberal use of CT for right lower quadrant pain, we reviewed our experience with selective CT and the effect this has had on our practice, paying particular attention to perforation rate and negative appendectomy rate.

MATERIALS AND METHODS

A retrospective chart review was performed for all patients who underwent appendectomy in 1995 and 1998. These two patient populations were evaluated for patient demographics, use of CT scan, perforation rate, and incidence of negative appendectomy.

RESULTS

Three hundred ninety-four patients underwent appendectomy in 1995 versus 372 in 1998. Gender (64% male in 1995 vs. 60% in 1998), age (mean 24.9 vs. 25.5) and perforation rate (31% in 1995 vs. 29% in 1998) did not change. The use of CT increased in 1998 (12% vs. 34%, p < 0.001) and overall nontherapeutic appendectomy decreased (14% vs. 7%, p < 0.005). This decrease was seen in patients who were operated without CT (13% vs. 7%, p < 0.03) and after CT (19% vs. 6%, p < 0.02).

CONCLUSION

Selective use of CT scan in patients presenting with right lower quadrant pain is helpful in reducing the incidence of nontherapeutic appendectomy.