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

Routine Computed Tomography Versus Selective Imaging: An Audit of Negative Appendicectomy Rates in Two Hospitals

Introduction There are a variety of conflicting recommendations in the literature for pre-operative imaging in acute appendicitis. There is debate over what the ideal imaging protocol is to lower the negative appendicectomy rate (NAR) without increasing missed appendicitis. The aim of this study is to compare the audited NAR between two groups with different imaging approaches: (i) mandatory pre-operative computed tomography (CT) imaging and (ii) selective imaging with CT, ultrasound (US), or no imaging prior to appendicectomy. Materials and methods A retrospective chart audit was conducted of 400 patients who underwent an appendicectomy at two hospitals with different approaches to pre-operative imaging (hospital A and hospital B). The primary outcome measure was histologically confirmed appendicitis. It was also documented whether there was radiological (CT or US) evidence of appendicitis.  Results At hospital A, all 200 patients underwent CT imaging prior to appendicectomy. The total histologically confirmed NAR for this group was 9.5% (19/200). At hospital B, 97 (48.5%) patients underwent CT, 41 (25.5%) underwent US, 10 (5%) had both US and CT, and 52 (26%) had no imaging. The total NAR was 11.5% (23/200). Conclusion There was no statistically significant difference (p=0.62) in audited NARs when comparing clinician-guided selective imaging versus routine CT imaging for all patients undergoing appendicectomy.

Non-Operative Management of Appendicitis: Evolution, not Revolution

Background: The medical fascination with the appendix vermiformis dates from the clandestine prosectors of the fifteenth century. The surgical management of appendiceal inflammation dates from 1735, but acceptance that acute appendicitis (AA) should be treated primarily by resection with or without drainage would not follow for 150 years. Recent publication of several randomized clinical trials (RCTs) of non-operative management (NOM) of AA affords the opportunity to review the historical record, describe the evolution of AA management toward NOM, and assess what is in the best interest of the patient. Methods: Review and synthesis of historical and contemporary English, French, German, and Italian literature with expert opinion. Results: Modern understanding of AA dates to the landmark 1886 clinico-pathologic correlative study by Reginald Fitz, which coined the term appendicitis and coincided with recognition by surgeons that AA could be diagnosed pre-operatively and managed surgically, with mortality rates of approximately 10%. Not until 1901 did Albert Ochsner advocate NOM, paradoxically for severe cases unlikely to survive operation. Markedly decreased mortality coincided with the introduction of sulfanilamide in 1935 and penicillin and curare in 1942. The first large series of patients with AA treated primarily with NOM was published in 1956 by Eric Coldrey. Modern management evolved rapidly in the late twentieth century, including effective anti-anaerobic antibiotic agents (1970s), laparoscopic appendectomy (LA; 1980), and pelvis computed tomography with rectal contrast (1998) all representing important contributions. Randomized controlled trials of NOM of AA date to 1995, with one large trial (2015) showing that open appendectomy was not non-inferior to NOM, and another (2020) demonstrating non-inferiority between (mostly) LA and NOM. However, one-year failure rates are high (∼30%) and appear to increase further with longer follow-up. Conclusions: Laparoscopic appendectomy is curative and cost-effective management for AA, with low morbidity. Results of recent RCTs of NOM of AA indicate that LA remains the treatment of choice, particularly if a fecalith is present. However, patient preferences must be taken into account; some may prefer NOM for the 60%-70% chance that surgery may be avoided, which should be considered when providing informed consent. Non-operative management should be undertaken in the outpatient setting if possible. Antibiotic management-whether or not for NOM-should adhere to the principles of stewardship.

Point-of-care ultrasound for the acute abdomen in the primary health care

Point-of-care ultrasound (POCUS) is a focused examination, which is performed and interpreted at the bedside by the treating physician answering a specific clinical question. It is currently utilized as an essential adjunct to physical examination in many medical specialties. Recent advances in technology have made POCUS machines portable, affordable, and could be used with minimal training even by nonradiologists. This review aims to cover the fundamental physics of POCUS and its applications for diagnosing the acute abdomen in the primary health care including the most common causes encountered by family physicians. These are acute appendicitis, acute cholecystitis, renal colic, ectopic pregnancy, acute diverticulitis, bowel obstruction, and abdominal aortic aneurysm. We hope to encourage primary care physicians to incorporate POCUS in their routine clinical practice. We also highlight challenges encountered when using POCUS in the primary health care including limited availability and the need for proper training. Furthermore, we review the POCUS results when performed by primary health-care physicians. Integrating POCUS in primary health care empowers primary health-care physicians to provide high-quality, safe, and cost-effective care to the patients.

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.

Diagnostic Performance of Surgical Criteria Incorporating MDCT for Suspected Acute Appendicitis

Objective

The objective of this study was to evaluate the effectiveness of a new set of criteria and multidetector computed tomography (MDCT) in determining whether surgical intervention is required in cases of appendicitis, with the aim of reducing unnecessary procedures and postoperative complications.

Methods

The patients were divided into 2 groups: group A, comprising patients who were admitted between 2008 and 2013 and treated based on the new criteria; and group B, comprising patients who were admitted between 2003 and 2007 and treated based on the standard criteria. Positive and negative predictive values were calculated.

Results

Of 1021 patients, 533 (274 males, 259 females) belonged to group A and 488 (263 males, 225 females) to group B. Surgical procedures were performed in 46.0% (245 cases) of patients in group A and 64.3% (314 cases) in group B (P > 0.001). The rate of conservative treatment was significantly higher in group A. The overall rate of catarrhal appendicitis based on histopathologic findings was 6.9% (17 cases) in group A and 15.0% (47 cases) in group B (P > 0.003). The overall rate of surgical complications was significantly higher in group B, being observed in 14.6% (46 cases) in this group, but only 8.2% (20 cases) in group A (P > 0.02). No statistically significant difference was observed in rate of conversion to surgery after conservative therapy or recurrence between the 2 groups.

Conclusion

Our new surgical criteria incorporating MDCT are effective in reducing the incidence of negative appendectomies and surgical complications.

Randomized clinical trial of Appendicitis Inflammatory Response score-based management of patients with suspected appendicitis

BACKGROUND

The role of imaging in the diagnosis of appendicitis is controversial. This prospective interventional study and nested randomized trial analysed the impact of implementing a risk stratification algorithm based on the Appendicitis Inflammatory Response (AIR) score, and compared routine imaging with selective imaging after clinical reassessment.

METHOD

Patients presenting with suspicion of appendicitis between September 2009 and January 2012 from age 10 years were included at 21 emergency surgical centres and from age 5 years at three university paediatric centres. Registration of clinical characteristics, treatments and outcomes started during the baseline period. The AIR score-based algorithm was implemented during the intervention period. Intermediate-risk patients were randomized to routine imaging or selective imaging after clinical reassessment.

RESULTS

The baseline period included 1152 patients, and the intervention period 2639, of whom 1068 intermediate-risk patients were randomized. In low-risk patients, use of the AIR score-based algorithm resulted in less imaging (19·2 versus 34·5 per cent; P < 0·001), fewer admissions (29·5 versus 42·8 per cent; P < 0·001), and fewer negative explorations (1·6 versus 3·2 per cent; P = 0·030) and operations for non-perforated appendicitis (6·8 versus 9·7 per cent; P = 0·034). Intermediate-risk patients randomized to the imaging and observation groups had the same proportion of negative appendicectomies (6·4 versus 6·7 per cent respectively; P = 0·884), number of admissions, number of perforations and length of hospital stay, but routine imaging was associated with an increased proportion of patients treated for appendicitis (53·4 versus 46·3 per cent; P = 0·020).

CONCLUSION

AIR score-based risk classification can safely reduce the use of diagnostic imaging and hospital admissions in patients with suspicion of appendicitis. Registration number: NCT00971438 ( http://www.clinicaltrials.gov).

How to diagnose an acutely inflamed appendix; a systematic review of the latest evidence

Acute appendicitis is the most common condition that presents with an acute abdomen needing emergency surgery. Despite this common presentation, correctly diagnosing appendicitis remains a challenge as clinical signs or positive blood results can be absent in 55% of the patients. The reported proportion of missed diagnoses of appendicitis ranges between 20% and 40%. A delay or mis-diagnosis of appendicitis can result in severe complications such as perforation, abscess formation, sepsis, and intra-abdominal adhesions. Literature has shown that patients who had a negative appendectomy suffer post-op complications and infections secondary to hospital stays; there have even been reported cases of fatality. It is therefore crucial that timely and accurate diagnosis of appendicitis is achieved to avoid complications of both non-operating as well as unnecessary surgical intervention. The aim of this review is to systematically report and analyse the latest evidence on the different approaches used in diagnosing appendicitis. We include discussions of clinical scoring systems, laboratory tests, latest innovative bio-markers and radiological imaging.

Prime time to resuscitate clinical medicine and kill diagnostic greed?

Modern healthcare faces the challenges of rising costs, increasing expectations of patients and changing disease patterns. Physicians practise medicine in an era of easy availability and access to a plethora of modern and sometimes expensive diagnostic aids. The powerful utility of clinical skills cannot be underestimated nor lost. The physician has a powerful platform to encourage the rational use of tests, prevent wasteful overutilisation and ensure that tests do not cause more harm than benefit in physical, emotional or financial terms. Diagnostic skills should not be substituted by diagnostic greed. It is possible to do more for the patient rather than to the patient.

Is acute appendicitis still misdiagnosed?

Objective

The optimal diagnostics and treatment of acute appendicitis continues to be a challenge. A false positive diagnosis of appendicitis may lead to an unnecessary operation, which has been appropriately termed negative appendectomy. The aim of our study was to identify the effectiveness of preoperative investigations in preventing negative appendectomy.

Methods

A retrospective study was performed on adult patients who underwent operation for suspected acute appendicitis from 2008 to 2013 at Vilnius University Hospital Santariskiu Klinikos. Patients were divided into two groups: group A underwent an operation, where appendix was found to be normal (non-inflamed); group B underwent an appendectomy for inflamed appendix. Groups were compared for preoperative data, investigations, treatment results and pathology findings.

Results

554 patients were included in the study. Preoperative laboratory tests results of hemoglobin, hematocrit concentrations and white blood cell count were significantly higher in group B (p<0.001). Ultrasonography was performed for 78 % of patients in group A and 74 % in group B and did not provide any statistically significant results. Comparing Alvarado score results, there were more patients with Alvarado score less than 7 in group A than in group B. In our large series we could find only four independent risk factors, and they could only account for 24 % of cases.

Conclusions

In summary, acute appendicitis is still often misdiagnosed and the ratio of negative appendectomies remains rather high. Additional investigations such as observation and computed tomography should be used to prevent this.

Acute Appendicitis: The Reliability of Diagnosis by Clinical Assessment Alone

Background and Aims:

This prospective study aimed to review the trustworthiness of the initial clinical assessment in acute appendicitis without employment of imaging modalities, laparoscopy or any other adjunct diagnostic test.

Patients and Methods:

717 patients were operated on for appendicitis by six different surgeons. Initial clinical and laboratory examination were evaluated in relation to the intraoperative and the pathological appreciation of the appendiceal inflammation.

Results:

598 patients were found to have appendicitis, 34 a different condition, 41 had both appendicitis and an additional condition and 44 no pathology. 6% of the laparotomies and 11 % of the appendectomies were unnecessary. The severity of the inflammation correlated significantly with periumbilical pain, pain migrating to right lower quadrant, loss of appetite, fever, rebound tenderness, local rigidity, polymorphonuclear predominance on deferential, polymorhonucleosis and leukocytosis. Leukocytosis was less frequent in aged patients. All the six surgeons were found to be equally reliable, although they all underestimated the setting compared to the pathologists. Patients with a long duration of symptoms had milder forms of inflammation and increased percentage of unanticipated abdominal conditions.

Conclusions:

Appendicitis can be reliably diagnosed clinically without employment of adjunct tests. These can be reserved for equivocal cases.

How to improve the clinical diagnosis of acute appendicitis in resource limited settings

This article is a general review of the diagnostic tools that the clinician can use for the early diagnosis of acute appendicitis with emphasis on the Alvarado Score, and it is aimed principally to the medical practitioners in different parts of the world where the diagnostic facilities and technological resources are limited.

Predicting acute appendicitis? A comparison of the Alvarado score, the Appendicitis Inflammatory Response Score and clinical assessment

BACKGROUND

Patients presenting with suspected appendicitis pose a diagnostic challenge. The appendicitis inflammatory response (AIR) score has outperformed the Alvarado score in two retrospective studies. The aim of this study was to evaluate the AIR Score and compare its performance in predicting risk of appendicitis to both the Alvarado score and the clinical impression of a senior surgeon.

METHODS

All parameters included in the AIR and Alvarado scores as well as the initial clinical impression of a senior surgeon were prospectively recorded on patients referred to the surgical on call team with acute right iliac fossa pain over a 6-month period. Predictions were correlated with the final diagnosis of appendicitis.

RESULTS

Appendicitis was the final diagnosis in 67 of 182 patients (37 %). The three methods of assessment stratified similar proportions (~40 %) of patients to a low probability of appendicitis (p = 0.233) with a false negative rate of <8 % that did not differ between the AIR score, Alvarado score or clinical assessment. The AIR score assigned a smaller proportion of patients to the high probability zone than the Alvarado score (14 vs. 45 %) but it did so with a substantially higher specificity (97 %) and positive predictive value (88 %) than the Alvarado score (76 and 65 %, respectively).

CONCLUSIONS

The AIR score is accurate at excluding appendicitis in those deemed low risk and more accurate at predicting appendicitis than the Alvarado score in those deemed high risk. Its use as the basis for selective CT imaging in those deemed medium risk should be considered.

Gastrointestinal causes of abdominal pain

Gastrointestinal causes of abdominal pain are numerous. These causes are reviewed in brief here, divided into 2 categories: acute abdominal pain and chronic abdominal pain. They are further subcategorized by location of pain as it pertains to the abdomen.

Risk stratification by the Appendicitis Inflammatory Response score to guide decision-making in patients with suspected appendicitis

BACKGROUND

Current management of suspected appendicitis is hampered by the overadmission of patients with non-specific abdominal pain and a significant negative exploration rate. The potential benefits of risk stratification by the Appendicitis Inflammatory Response (AIR) score to guide clinical decision-making were assessed.

METHODS

During this 50-week prospective observational study at one institution, the AIR score was calculated for all patients admitted with suspected appendicitis. Appendicitis was diagnosed by histological examination, and patients were classified as having non-appendicitis pain if histological findings were negative or surgery was not performed. The diagnostic performance of the AIR score and the potential for risk stratification to reduce admissions, optimize imaging and prevent unnecessary explorations were quantified.

RESULTS

A total of 464 patients were included, of whom 210 (63·3 per cent) with non-appendicitis pain were correctly classified as low risk. However, 13 low-risk patients had appendicitis. Low-risk patients accounted for 48·1 per cent of admissions (223 of 464), 57 per cent of negative explorations (48 of 84) and 50·7 per cent of imaging requests (149 of 294). An AIR score of 5 or more (intermediate and high risk) had high sensitivity for all severities of appendicitis (90 per cent) and also for advanced appendicitis (98 per cent). An AIR score of 9 or more (high risk) was very specific (97 per cent) for appendicitis, and the majority of patients with appendicitis in the high-risk group (21 of 30, 70 per cent) had perforation or gangrene. Ultrasound imaging could not exclude appendicitis in low-risk patients (negative likelihood ratio (LR) 1·0) but could rule-in the diagnosis in intermediate-risk patients (positive LR 10·2). CT could exclude appendicitis in low-risk patients (negative LR 0·0) and rule-in appendicitis in the intermediate group (positive LR 10·9).

CONCLUSION

Risk stratification of patients with suspected appendicitis by the AIR score could guide decision-making to reduce admissions, optimize utility of diagnostic imaging and prevent negative explorations.

Gastrointestinal imaging-practical magnetic resonance imaging approach

Over the past two decades, advances in cross-sectional imaging such as computed tomography and magnetic resonance imaging (MRI) have dramatically changed the concept of gastrointestinal imaging. MR is playing an increasing role in the evaluation of gastrointestinal disorders. MRI combines the advantages of excellent soft-tissue contrast, noninvasiveness, functional information and lack of ionizing radiation. Furthermore, recent developments of MRI have led to improved spatial and temporal resolution as well as decreased motion artifacts. In this article we describe the technical aspects of gastrointestinal MRI and present a practical approach for a well-known spectrum of gastrointestinal disease processes.

Improvement in the diagnosis of appendicitis

Our attempts to systematically improve accuracy in the evaluation of patients with suspected appendicitis are, in some ways, hindered by the fact that the condition is so frequently straightforward to diagnose. Careful history-taking and physical examination are reliable in most patients. However, establishing the diagnosis with these skills alone remains vulnerable to conditions that masquerade as acute appendicitis. A substantial body of clinical research over the last quarter-century has shown that improved accuracy is possible. Strategies for improvement include the use of diagnostic scoring systems, laboratory makers such as CRP, diagnostic laparoscopy, and advanced imaging modalities such as CT, MRI, and US. How clinicians use these strategies depends on many factors related to practice setting, the population served, and clinical goals. In children, for instance, the desire to limit exposure to ionizing radiation competes with the greater anatomic detail that a CT scan can provide; at the same time, many hospitals that treat children do not have the resources to maintain the sort of full-time, highly sophisticated abdominal US programs that achieve the highest rates of diagnostic accuracy in clinical studies. Trade-offs have to be made, but improvement is possible in almost all groups of patients: the clinical community should no longer settle for a 15% NA rate when 5% is clearly possible without adverse consequences. Many clinicians will be faced with the task of evaluating patients suspected of having acute appendicitis. A deliberate, proactive, and, ideally, benchmarked strategy for improving diagnosis should be the standard to which we hold ourselves and the promise we deliver to our patients.

The role of US examination in the management of acute abdomen

Acute abdomen is a medical emergency, in which there is sudden and severe pain in abdomen of recent onset with accompanying signs and symptoms that focus on an abdominal involvement. It can represent a wide spectrum of conditions, ranging from a benign and self-limiting disease to a surgical emergency. Nevertheless, only one quarter of patients who have previously been classified with an acute abdomen actually receive surgical treatment, so the clinical dilemma is if the patients need surgical treatment or not and, furthermore, in which cases the surgical option needs to be urgently adopted. Due to this reason a thorough and logical approach to the diagnosis of abdominal pain is necessary. Some Authors assert that the location of pain is a useful starting point and will guide a further evaluation. However some causes are more frequent in the paediatric population (like appendicitis or adenomesenteritis) or are strictly related to the gender (i.e. gynaechologic causes). It is also important to consider special populations such as the elderly or oncologic patients, who may present with atypical symptoms of a disease. These considerations also reflect a different diagnostic approach. Today, surely the integrated imaging, and in particular the use of multidetector Computed Tomography (MDCT) has revolutionised the clinical approach to this condition, simplyfing the diagnosis but burdening the radiologists with the problems related to the clinical management. However although CT emerging as a modality of choice for evaluation of the acute abdomen, ultrasonography (US) remains the primary imaging technique in the majority of cases, especially in young and female patients, when the limitation of the radiation exposure should be mandatory, limiting the use of CT in cases of nondiagnostic US and in all cases where there is a discrepancy between the clinical symptoms and negative imaging at US.

Accuracy of 64-row multidetector CT in the diagnosis of surgically treated acute abdomen

OBJECTIVE

To assess the accuracy of 64-row computed tomography (CT) in the differential diagnosis of acute abdomen in the emergency department.

MATERIALS AND METHODS

Prospective analysis of 181 patients with surgically treated acute abdomen.

RESULTS

In 158/181 cases, CT was totally concordant with surgical repertoire. Partial concordance was found in 15 cases. Overall sensitivity was 87.3% when only cases of complete concordance were considered, 95.6% if also partial concordance cases were included.

CONCLUSION

CT showed high reliability in the differential diagnosis of acute abdomen surgically treated, although associated conditions can sometimes be missed.

Alvarado score: a guide to computed tomography utilization in appendicitis

BACKGROUND

Although useful in evaluation of suspected appendicitis, not all patients require computed tomography (CT) evaluation. Clinical stratification of patients who benefit from CT evaluation is essential. We utilize the Alvarado score (AS) to stratify patients with suspected appendicitis into subgroups who benefit from CT evaluation and propose an objective algorithm with AS guiding CT utilization.

METHODS

This study is a retrospective review of medical records of all patients admitted for suspected appendicitis over a 6-month duration. Relevant data were recorded. The AS for each patient was determined retrospectively and correlated with histological and CT findings. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were determined for various ASs and for CT.

RESULTS

Three hundred fifty-eight patients were studied, with 167 males (46.6%) and 191 females (53.4%). Prevalence of appendicitis was 50% (179 patients). Two hundred fourteen patients (59.8%) had CT performed. Surgery was performed for 206 patients (57.5%). Overall negative appendicectomy rate was 13.1%. Patients who underwent CT evaluation had a negative appendicectomy rate of 5.7% compared to 17.9% in those without CT evaluation (P = 0.009). CT scan had a sensitivity and specificity of 92.6% and 96.9%, respectively. An AS greater than 3 had a sensitivity superior to CT (95.5%), while an AS of 9 or greater had a specificity superior to CT (100%).

CONCLUSIONS

In suspected appendicitis, patients who benefit from CT evaluation are those with the AS ranging from 4 to 8. We propose a management algorithm with the AS guiding the necessity for CT evaluation.

ACR Appropriateness Criteria® right lower quadrant pain--suspected appendicitis

The diagnostic imaging of patients presenting with right lower quadrant pain and suspected appendicitis may be organized according to age and gender and to the presence or absence of "classic" signs and symptoms of acute appendicitis. Among adult patients presenting with clinical signs of acute appendicitis, the sensitivity and specificity of CT are greater than those of ultrasound, with improved performance when CT is performed with intravenous contrast. The use of rectal contrast has been associated with decreased time in the emergency department. Computed tomography has also been shown to reduce cost and negative appendectomy rates. Both CT and ultrasound are also effective in the identification of causes of right lower quadrant pain unrelated to appendicitis. Among pediatric patients, the sensitivity and specificity of graded-compression ultrasound can approach those of CT, without the use of ionizing radiation. Performing MRI after inconclusive ultrasound in pregnant patients has been associated with sensitivity and specificity of 80% to 86% and 97% to 99%, respectively. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

The value of hyperbilirubinaemia in the diagnosis of acute appendicitis

INTRODUCTION

No reliably specific marker for acute appendicitis has been identified. Although recent studies have shown hyperbilirubinaemia to be a useful predictor of appendiceal perforation, they did not focus on the value of bilirubin as a marker for acute appendicitis. The aim of this study was to determine the value of hyperbilirubinaemia as a marker for acute appendicitis.

MATERIALS AND METHODS

A retrospective analysis of appendicectomies performed in two hospitals (n=472). Data collected included laboratory and histological results. Patients were grouped according to histology findings and comparisons were made between the groups.

RESULTS

The mean bilirubin levels were higher for patients with simple appendicitis compared to those with a non-inflamed appendix (p<0.001). More patients with simple appendicitis had hyperbilirubinaemia on admission (30% vs 12%) and the odds of these patients having appendicitis were over three times higher (odds ratio: 3.25, p<0.001). Hyperbilirubinaemia had a specificity of 88% and a positive predictive value of 91% for acute appendicitis. Patients with appendicitis who had a perforated or gangrenous appendix had higher mean bilirubin levels (p=0.01) and were more likely to have hyperbilirubinaemia (p<0.001). The specificity of hyperbilirubinaemia for perforation or gangrene was 70%. The specificities of white cell count and C-reactive protein were less than hyperbilirubinaemia for simple appendicitis (60% and 72%) and perforated or gangrenous appendicitis (19% and 36%).

CONCLUSIONS

Hyperbilirubinaemia is a valuable marker for acute appendicitis. Patients with hyperbilirubinaemia are also more likely to have appendiceal perforation or gangrene. Bilirubin should be included in the assessment of patients with suspected appendicitis.

Pediatric appendicitis score: A retrospective analysis

Aims:

Evaluation of the pediatric appendicitis score (PAS), in all patients who had an appendicectomy over a one-year period.

Methods:

Retrospective study of 56 patients aged 4–15 years, who underwent an emergency appendicectomy. PAS was applied and patients were divided according to the PAS protocol into high probability and low probability groups. These results were then correlated with histology.

Results:

The PAS had sensitivity 0.87, specificity 0.59, positive predictive value 0.83, and negative predictive value 0.67. The negative appendicectomy rate would have been reduced to 17%, but five patients with appendicitis would have been denied early surgical treatment and may have been discharged.

Conclusions:

The PAS cannot be recommended as it would lead to an unacceptable risk of wrongly discharging or delaying necessary surgery in 13% of patients with appendicitis.

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.

Analgesia in patients with acute abdominal pain

BACKGROUND

For decades, the indication of analgesia in patients with Acute Abdominal Pain (AAP) has been deferred until the definitive diagnosis has been made, for fear of masking symptoms, generating a change in the physical exploration or obstructing the diagnosis of a disease requiring surgical treatment. This strategy has been questioned by some studies that have shown that the use of analgesia in the initial evaluation of patients with AAP leads to a significant reduction in pain without affecting diagnostic accuracy.

OBJECTIVES

To determine whether the evidence available supports the use of opioid analgesics in the diagnostic process of patients with AAP.

SEARCH STRATEGY

Trials were identified through searches in Cochrane Controlled Trials Register (CENTRAL) (The Cochrane Library, issue 2, 2009), MEDLINE (1966 to 2009) and EMBASE (1980 to 2009). A randomised controlled trial (RCT) filter for a MEDLINE search was applied (with appropriate modification for an EMBASE search). Trials also were identified through "related articles". The search was not limited by language or publication status.

SELECTION CRITERIA

All published RCTs which included adult patients with AAP, without gender restriction, comparing any opioids analgesia regimen with the non-use of analgesic before any intervention and independent of the results.

DATA COLLECTION AND ANALYSIS

Two independent reviewers assessed the studies identified via the electronic search. Articles that were relevant and pertinent to the aims of the study were selected and their respective full-text versions were collected for subsequent blinded evaluation. The allocation concealment was considered in particular as an option to diminish the biases.The data collected from the studies were reviewed qualitatively and quantitatively using the Cochrane Collaboration statistical software RevMan 5.0. After performing the meta-analysis, the chi-squared test for heterogeneity was applied. In situations of significant clinical heterogeneity, statistical analyses were not applied to the pool of results. In situations of heterogeneity, the random effect model was used to perform the meta-analysis of the results. A sensitivity analysis was also applied based on the evaluation to the methodological quality of the primary studies.

MAIN RESULTS

Eight studies fulfilled the inclusion criteria. Differences with use of opioid analgesia were verified in variables: Change in the intensity of the pain, change in the patients comfort level.

AUTHORS' CONCLUSIONS

The use of opioid analgesics in the therapeutic diagnosis of patients with AAP does not increase the risk of diagnosis error or the risk of error in making decisions regarding treatment.

An evidence-based clinical protocol for diagnosis of acute appendicitis decreased the use of computed tomography in children

PURPOSE

The increased use of computed tomography (CT) to diagnose appendicitis in children has led to a concern for the possibility of increased CT-related cancer morbidity. We designed a clinical protocol for the diagnosis and treatment of appendicitis in children in an attempt to decrease the use of CT scans at our institution.

METHODS

Patients who had surgical consultation for suspected appendicitis were placed on the clinical protocol. Data concerning diagnosis and treatment were collected prospectively. Retrospective data from patients admitted to our institution with acute appendicitis before the clinical protocol were collected as historical controls.

RESULTS

One hundred twelve patients were diagnosed and treated by our protocol between June and November 2009. Of these, 100 patients underwent an appendectomy for acute appendicitis. They were compared with 146 patients from 2007. In-house CT use decreased from 71.2% to 51.7% (P = .01). Preoperative ultrasound use increased from 2.7% to 21% (P < .001). The negative appendectomy rate increased (6.8% vs 11%, P = .25).

CONCLUSIONS

Our findings suggest that the implementation of an evidence-based clinical protocol for the diagnosis and treatment of acute appendicitis in children may safely decrease the use of CT scans and increase the use of ultrasound.

Complicated intra-abdominal infections: a focus on appendicitis and diverticulitis

Severe abdominal pain is a common complaint encountered by primary care and emergency room physicians. Caused by many conditions, including appendicitis and diverticulitis, severe abdominal pain may be a diagnostic challenge. Although different in many ways, appendicitis and diverticulitis are caused by obstruction of a blind pouch that leads to inflammation of the structure and surrounding tissue. Appendicitis and diverticulitis are 2 of the most frequently diagnosed causes of complicated intra-abdominal infections. Combined, appendicitis and diverticulitis comprise > 80% of all community-acquired complicated intra-abdominal infections. These conditions are serious and require prompt diagnosis and treatment. Because complicated intra-abdominal infections are typically polymicrobial, a wide variety of causative pathogens are identified, including Gram-positive and Gram-negative aerobic and anaerobic microorganisms. Treatment for these disorders often requires surgical and medical management. Although surgical intervention can be the definitive treatment for complicated intra-abdominal infections, successful management of appendicitis and diverticulitis will depend on appropriate selection of antimicrobials and optimal duration of therapy to maximize the coverage of potential causative pathogens and to minimize the development of resistance. Guidelines for empiric treatment of complicated intra-abdominal infections recommend broad-spectrum antimicrobials as monotherapy or in combinations, including standard antimicrobial regimens, such as piperacillin/tazobactam, imipenem/cilastatin, and piperacillin-tazobactam/amoxicillin-clavulanate regimens, and fluoroquinolone-based regimens. This review article compares the presentations and treatments of these common complicated intra-abdominal infections.

Imaging patients with acute abdominal pain

Acute abdominal pain may be caused by a myriad of diagnoses, including acute appendicitis, diverticulitis, and cholecystitis. Imaging plays an important role in the treatment management of patients because clinical evaluation results can be inaccurate. Performing computed tomography (CT) is most important because it facilitates an accurate and reproducible diagnosis in urgent conditions. Also, CT findings have been demonstrated to have a marked effect on the management of acute abdominal pain. The cost-effectiveness of CT in the setting of acute appendicitis was studied, and CT proved to be cost-effective. CT can therefore be considered the primary technique for the diagnosis of acute abdominal pain, except in patients clinically suspected of having acute cholecystitis. In these patients, ultrasonography (US) is the primary imaging technique of choice. When costs and ionizing radiation exposure are primary concerns, a possible strategy is to perform US as the initial technique in all patients with acute abdominal pain, with CT performed in all cases of nondiagnostic US. The use of conventional radiography has been surpassed; this examination has only a possible role in the setting of bowel obstruction. However, CT is more accurate and more informative in this setting as well. In cases of bowel perforation, CT is the most sensitive technique for depicting free intraperitoneal air and is valuable for determining the cause of the perforation. Imaging is less useful in cases of bowel ischemia, although some CT signs are highly specific. Magnetic resonance (MR) imaging is a promising alternative to CT in the evaluation of acute abdominal pain and does not involve the use of ionizing radiation exposure. However, data on the use of MR imaging for this indication are still sparse.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/content/253/1/31/suppl/DC1.

Acute appendicitis: is removal of a normal appendix still existing and can we reduce its rate?

BACKGROUND/AIM

To determine the incidence of negative appendectomies and to identify factors that may reduce the risk of having the normal appendices removed surgically.

DESIGN

Cross-sectional study.

SETTING

College of Medicine and King Khalid University Hospital, Riyadh, Saudi Arabia.

MATERIALS AND METHODS

The surgical and histological data of 852 patients who underwent appendicectomy were reviewed. All incidental or interval appendicectomies were excluded. Only patients who were admitted and whose appendices were removed and subjected to histology were included (585 patients). The data on patients who had a normal appendix on histology further analyzed to include demographics, specific investigations, operative findings of the appendix and additional operative findings that need other surgical procedures.

RESULTS

A normal appendix was removed in 54 (9.2%) of the patients. Only 5.5% of those patients had a computed tomography (CT) scan preoperatively and 3.7% had diagnostic laparoscopy. In 21 patients, additional operative and histological findings were obtained that might have caused the right lower abdominal pain.

CONCLUSION

In spite of the advances in the diagnostic and imaging techniques, the rates of negative findings on appendicectomy have not decreased much. Clinical judgment is still the most important factor in the management of patients with suspected acute appendicitis. The routine use of CT scan or diagnostic laparoscopy for all patients who are suspected to have appendicitis is neither cost-effective nor safe.

CT scans and acute appendicitis: a five-year analysis from a rural teaching hospital

INTRODUCTION

Studies examining the relationship between computed tomography (CT) scans and appendiceal perforation have largely been conducted in urban centers. The present study sought to evaluate this relationship in a rural hospital.

METHODS AND PROCEDURES

This is a retrospective analysis of 445 patients who underwent appendectomies from January 2000 to June 2005 at a rural teaching hospital.

RESULTS

Four hundred forty-five patients were analyzed in two groups; those who underwent CT scans (N = 245) and those who did not (N = 200). Patients undergoing CT scans were significantly older (median age 38 vs. 22 years, P < 0.0001), were more likely to have perforated appendicitis (P 0.001), were less likely to undergo a negative appendectomy (P = 0.003), and had a significantly longer length of stay than those who did not (P 0.009). Analysis by gender showed that perforation rates continued to be significantly higher in males undergoing CT scans (P 0.004). To examine the possibility that sicker patients were more likely to receive CT scans and also be found to have perforated appendicitis, a sensitivity analysis was performed. Patients showing perforated appendicitis on initial CT scans were excluded and the analysis was repeated. The difference in perforation rates continued to remain significant (P 0.037).

CONCLUSION

Males undergoing CT scans are significantly more likely to have perforated appendicitis. A protocol-driven rational approach to CT evaluation of suspected appendicitis may lower perforation rates, especially in males.