Diagnosis of Acute Appendicitis During Pregnancy: A Systematic Review

Using MRI appendicitis scale and DWI for the diagnosis of acute appendicitis in pregnant women

OBJECTIVES

To assess the performance of MRI scale for the diagnosis of acute appendicitis in pregnant women and to determine the added diagnostic value of diffusion-weighted imaging (DWI).

METHODS

From January 2018 to December 2020, 80 patients were included. All MRI were performed with a 1.5-Tesla scanner with anterior array body coil. This analysis included (1) T2-weighted imaging (T2WI), (2) fat-saturated T2WI, and (3) DWI. Two radiologists blinded to the diagnosis recorded their assessment of four findings: appendiceal diameter, appendiceal wall thickness, luminal mucus, and periappendiceal inflammation. The MRI scale of acute appendicitis which ranged from 0 to 4 was determined from these factors. An additional one point was added to the MRI appendicitis scale in those patients with evidence of appendiceal restricted diffusion on DWI. The diagnostic values and predictive factors were computed.

RESULTS

Multivariate analysis demonstrated that the calculated MRI appendicitis scale was a significant independent predictor of acute appendicitis with a sensitivity of 96.6%, specificity of 90.2%, and PPV of 84.8%. The odds ratio of appendicitis is increased by 22.3 times for every increase in one point on the MRI appendicitis scale. Therefore, the addition of one point for restricted diffusion in the appendix on DWI imaging can add substantial value, both positive and negative predictive value, towards making an accurate diagnosis of acute appendicitis.

CONCLUSIONS

MRI appendicitis scale is an objective and significant independent predictive factor for acute appendicitis in pregnant women. Incorporation of diffusion weighted imaging to MRI can improve diagnosis of acute appendicitis.

CLINICAL RELEVANCE STATEMENT

MRI appendicitis scale is an objective and significant independent predictor of acute appendicitis in pregnant women. Incorporation of DWI/ADC map to MRI examinations can improve diagnosis of acute appendicitis in pregnant women.

KEY POINTS

• MRI appendicitis scale is an objective and significant independent predictive factor for acute appendicitis in pregnant women. • The odds ratio of appendicitis can be increased by 22.3 times for every increase of one unit in MRI scale. • Incorporation of diffusion-weighted imaging to MRI examinations can add value to the scale (4.2 ± 0.7 vs. 0.7 ± 1.1; p < 0.001) among pregnant women with appendicitis versus pregnant women without appendicitis.

Artificial Intelligence and Acute Appendicitis: A Systematic Review of Diagnostic and Prognostic Models

BACKGROUND

To assess the efficacy of artificial intelligence (AI) models in diagnosing and prognosticating acute appendicitis (AA) in adult patients compared to traditional methods. AA is a common cause of emergency department visits and abdominal surgeries. It is typically diagnosed through clinical assessments, laboratory tests, and imaging studies. However, traditional diagnostic methods can be time-consuming and inaccurate. Machine learning models have shown promise in improving diagnostic accuracy and predicting outcomes.

MAIN BODY

A systematic review following the PRISMA guidelines was conducted, searching PubMed, Embase, Scopus, and Web of Science databases. Studies were evaluated for risk of bias using the Prediction Model Risk of Bias Assessment Tool. Data points extracted included model type, input features, validation strategies, and key performance metrics.

RESULTS

In total, 29 studies were analyzed, out of which 21 focused on diagnosis, seven on prognosis, and one on both. Artificial neural networks (ANNs) were the most commonly employed algorithm for diagnosis. Both ANN and logistic regression were also widely used for categorizing types of AA. ANNs showed high performance in most cases, with accuracy rates often exceeding 80% and AUC values peaking at 0.985. The models also demonstrated promising results in predicting postoperative outcomes such as sepsis risk and ICU admission. Risk of bias was identified in a majority of studies, with selection bias and lack of internal validation being the most common issues.

CONCLUSION

AI algorithms demonstrate significant promise in diagnosing and prognosticating AA, often surpassing traditional methods and clinical scores such as the Alvarado scoring system in terms of speed and accuracy.

A novel Appendicitis TriMOdal prediction Score (ATMOS) for acute appendicitis in pregnancy: a retrospective observational study

Several scoring systems exist for the management of acute appendicitis (AA) during pregnancy. However, the systems are based on the nonpregnant adult population. The aim of this study was to create a highly accurate scoring system that can be applied to pregnant women and to compare it to the most commonly used scores in general population and pregnant women. The creation and subsequent implementation of a highly accurate score system could shorten the diagnostic period and minimize the use of (ionizing) diagnostic imaging allowing the selection of the best treatment approach in pregnant patients with acute appendicitis. A single-center, retrospective cohort observational study was conducted at the University Hospital Centre Zagreb, Zagreb, Croatia. Data were extracted from medical records of pregnant patients with suspected AA from January 2010 to December 2020. A total of 59 pregnant patients diagnosed with AA during pregnancy were identified, 41 were treated surgically, and 18 had non-surgical management. The main objective of our study was the detection of predictive factors of AA during pregnancy. Anorexia, pain migration to the right lower quadrant, rebound pain, axillary temperature over 37.3 °C, CRP/platelet ratio > 0.0422, neutrophil/lymphocyte ratio > 7.182, and ultrasonic signs of AA were scored. Scoring in Appendicitis TriMOdal Score (ATMOS) consists of positive clinical parameter, each bringing 1 point and other parameters mentioned above that bring 2 points each. The score ranges from 0 to 10. Our model of ATMOS yields a high area under the receiver-operating characteristic curve of 0.963. The positive likelihood ratio is 9.97 (95% CI 2.64-38.00), and the negative likelihood ratio is 0.1 (95% CI 0.03-0.31), meaning that 94% of cases with ATMOS > 4 have AA, while less than 13% with an ATMOS ≤ 4 have the diagnosis of AA. The potential of ATMOS differentiating AA during pregnancy was demonstrated. Future prospective, randomized trials are needed to evaluate its accuracy and whether it should be used instead of Alvarado or Tzanakis scores in clinical decision-making.Trial registration number ClinicalTrials.gov-NCT05202483. Date of registration: January 21, 2022.

The diagnostic accuracy of ultrasound in the diagnosis of acute appendicitis in pregnancy

Objective: Clinically suspected appendicitis is the most common nonobstetric surgical problem encountered in pregnancy. The diagnosis of appendicitis is hampered by equivocal symptoms during pregnancy. Ultrasonography (US) remains, as a rule, the imaging test of choice for the diagnosis of clinically suspected appendicitis during pregnancy and other imaging tools such as computed tomography (CT) or magnetic resonance imaging (MRI) are usually avoided. We evaluated the accuracy of US in the diagnosis of appendicitis during pregnancy.Methods: The clinical and sonographic findings of all pregnant women (n = 90), who underwent appendectomy between January 2005 and December 2017 at our institution, were retrospectively reviewed, analyzed, and compared to the clinical and sonographic findings similarly obtained for a control group of nonpregnant women matched for age and date of surgery (±6 months). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of ultrasonic findings were calculated and compared between groups as well as within the three pregnancy trimesters.Results: The mean age of the patients was 31.3 ± 0.4. Right lower quadrant pain was present in almost all patients (99%). The sole imaging modality used in our study cohort was US. Among nonpregnant controls, CT scan was primarily used on more occasions (53.3%) compared to US (45.6%). Nonpregnant women underwent significantly more laparoscopies compared to pregnant women (83.3 versus 45.6%, p < .001). The rate of negative appendectomy was higher in pregnant women (31.1 versus 10%, p = .002). Among pregnant women operated there was a higher rate of inconclusive or negative imaging (43.3 versus 11.1%, p < .001). The rate of perforated appendix at surgery was similar in both groups (6.7 and 4.4%, respectively, p = .75).Conclusions: Ultrasonography (US) is of mediocre accuracy for the diagnosis of acute appendicitis in pregnant patients beyond the first trimester of pregnancy. Thirty percent of pregnant women with suspected appendicitis are futilely operated. Given the low yield of US, a second-line imaging should be considered in cases of inconclusive US before surgery.

Laparoscopic surgery for non-obstetric acute abdomen in pregnancy: A retrospective case series review

BACKGROUND

Laparoscopic techniques have been used during pregnancy by obstetricians since the 1970's, primarily to diagnose and treat ectopic and heterotopic pregnancies. Pregnancy was considered as an absolute contraindication to laparoscopy by surgeons as recently as 1991, and a few still doubt the safety of minimal access in gravid patients. When an emergent operation is indicated, the surgery should not be withheld on the sole basis of patient's gravid state. On the contrary, the alleviation of maternal disease is thought to take priority because the health of the foetus is dependant on the mother.

MATERIALS AND METHODS

This is a retrospective study of a case series of 18 obstetric patients who presented with non-obstetric causes of acute abdomen requiring surgical intervention. Ultrasonography and magnetic resonance imaging (MRI) along with other laboratory investigations were carried out to reach the diagnosis. Laparoscopic surgery was considered as the modality of treatment. All the patients were given the necessary care post-surgery and were followed up till parturition to look for any complications.

RESULTS

The data were analysed considering the presentation, diagnostic variations and the surgical modifications statistically.

CONCLUSION

The decision of surgery should be prompt and should be weighed against complications of conserving the patient. Due to the diagnostic limitations of ultrasonography, MRI should be coupled to confirm the diagnosis. Laparoscopy offers less analgesic requirements and shorter hospital stay. The operative time is highly subjective to the experience and training of the surgeon and the laparoscopic set-up itself.

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.

Suspicion of appendicitis in pregnant women: emergency evaluation by sonography and low-dose CT with oral contrast

OBJECTIVES

To evaluate non-intravenously enhanced low-dose computed tomography with oral contrast (LDCT) for the assessment of pregnant women with right lower quadrant pain, when magnetic resonance imaging (MRI) is not immediately available.

METHODS

One hundred and thirty-eight consecutive pregnant women with acute abdominal pain were admitted in our emergency centre. Thirty-seven (27%) of them, with clinical suspicion of acute appendicitis, underwent abdominal ultrasonography (US). No further examination was recommended when US was positive for appendicitis, negative with low clinical suspicion or showed an alternative diagnosis which explained the clinical presentation. All other patients underwent LDCT (<2.5 mSv). Standard intravenously enhanced CT or MRI was performed when LDCT was indeterminate.

RESULTS

Eight (22%) of 37 US exams were reported normal, 25 (67%) indeterminate, 1 (3%) positive for appendicitis, 3 (8%) positive for an alternative diagnosis. LDCT was obtained in 29 (78%) patients. It was reported positive for appendicitis in 9 (31%), for alternative diagnosis in 2 (7%), normal in 13 (45%) and indeterminate in 5 (17%). Further imaging (standard CT or MRI) showed appendicitis in 2 of these 5 patients, was truly negative in 1, indeterminate in 1 and falsely positive in 1. An appendicitis was confirmed at surgery in 12 (32%) of the 37 patients. The sensitivity and the specificity of the algorithm for appendicitis were 100% (12/12) and 92% (23/25), respectively.

CONCLUSIONS

The proposed algorithm is very sensitive and specific for detection of acute appendicitis in pregnant women; it reduces the need of standard CTs when MRI is not available as second-line imaging.

KEY POINTS

• In pregnant women, US is limited by an important number of indeterminate results • Low-dose CT can be used after an inconclusive US for the diagnosis of appendicitis in pregnant women • An algorithm integrating US and low-dose CT is highly sensitive and specific for appendicitis in pregnant women.

Accuracy of ultrasonography in diagnosing acute appendicitis during pregnancy based on surgical findings

Background: Acute appendicitis is the most common nonobstetric surgical problem in pregnancy. Common signs and symptoms of appendicitis are less reliable during pregnancy due to physiological changes; thus, the role of imaging becomes prominent. Thus, in the present study, we aimed at assessing the accuracy of sonography in diagnosing acute appendicitis during pregnancy. Methods: In this prospective analytic study, among 1000 patients diagnosed and treated as acute appendicitis, clinical and sonographic findings of 58 consecutive pregnant patients, who underwent appendectomy, were recorded and analyzed. All surgically resected samples were evaluated and confirmed through histological evaluation. Sonographic criteria were utilized to judge the results for appendicitis. Diagnostic test performance characteristics (sensitivity, specificity, predictive values, and likelihood ratios) were calculated. Results: The mean age of the patients was 27.1±4.9 years, and the most common clinical symptom was right lower quadrant pain. There was no significant difference in the mean leukocyte count between the appendicitis group and normal appendix group (p=0.768). Left shift was also unrelated with the appendix pathology (p= 0.549). The sensitivity, specificity, predictive values (positive and negative), and likelihood ratios (positive and negative) were 80%, 75%, 91.4%, 52.9%, 3.2, and 0.26, respectively during all trimesters of pregnancy. Conclusion: Ultrasonography is the initially preferred imaging modality in pregnant women suspected of having acute appendicitis with an acceptable sensitivity; however, application of other imaging modalities such as CT scan or MRI is recommended after inconclusive ultrasonography results.

MRI for appendicitis in pregnancy: is seeing believing? clinical outcomes in cases of appendix nonvisualization

PURPOSE

The primary objective of this study was to determine the clinical outcomes in cases of appendix nonvisualization with MRI in pregnant patients with suspected appendicitis and the implications of appendix nonvisualization for excluding appendicitis.

METHODS

Fifty-eight pregnant patients with suspected appendicitis evaluated with MRI at three centers from a single institution were retrospectively reviewed by three radiologists with varying levels of abdominal imaging experience. All scans were performed on a 1.5-Tesla Siemens unit. Cases were evaluated for diagnostic quality, visualization of the appendix, presence of appendicitis, and alternate diagnoses. Clinical outcomes were gathered from the electronic medical record.

RESULTS

Of the 58 patients who underwent MRI for suspected appendicitis, 50 cases were considered adequate diagnostic quality by all three radiologists. The rate of appendix visualization among the three radiologists ranged from 60 to 76% (p = 0.44). The appendix was nonvisualized by at least one of the three radiologists in 25 cases (50%). Of these, none had a final diagnosis of appendicitis including one patient who underwent appendectomy. MRI suggested an alternate diagnosis in 6 (24%) patients with appendix nonvisualization. For the three reviewers, the agreement level on whether or not the appendix was visualized on the MRI had a Light's kappa value of 0.526, indicating a "moderate" level of agreement (p value < 0.01).

CONCLUSION

Despite only moderate level of interobserver agreement for appendix visualization, appendix nonvisualization on MRI in pregnant patients with suspected appendicitis confers a significant reduction in the risk of appendicitis compared to all comers as long as the study is adequate diagnostic quality and there are no secondary signs of appendicitis present.

The diagnostic performance of ultrasound for acute appendicitis in pregnant and young nonpregnant women: A case-control study

BACKGROUND

Ultrasonography is frequently used to diagnose acute appendicitis in women of reproductive age, but its diagnostic value in pregnant patients remains unclear. This study sought to compare the diagnostic performance of ultrasound in pregnant and young nonpregnant women with suspected acute appendicitis.

METHODS

The database of a single tertiary medical center was reviewed for all women of reproductive age who underwent appendectomy either during pregnancy (2000-2014) or in the nonpregnant state (2004-2007) following ultrasound evaluation. The performance of ultrasound in terms of predicting the final pathologic diagnosis was compared between the pregnant and non pregnant groups using receiver operating characteristic curve analysis.

RESULTS

Of 586 young women treated for appendicitis during the study periods (92 pregnant, 494 non-pregnant), 200 underwent preoperative ultrasound [67 pregnant, and 133 nonpregnant young women]. The pregnant and nonpregnant groups were comparable in age and presenting symptoms. There was no significant difference in the predictive performance of ultrasound between the two groups (AUC 0.76 and 0.73 respectively, p = 0.78) or within the pregnant group, by trimester [first (n = 23), AUC 0.73; second (n = 32), AUC 0.67; third (n = 12), AUC 0.86; p = 0.4]. Ultrasound had a positive predictive value of 0.94 in the pregnant group and 0.91 in the nonpregnant group; corresponding negative predictive values were 0.40 and 0.43.

CONCLUSIONS

There appears to be no difference in the ability of ultrasound to predict the diagnosis of acute appendicitis between pregnant women and nonpregnant women of reproductive age. Therefore, similar preoperative imaging algorithms may be used in both patient populations.

A Systematic Review and Meta-Analysis of Diagnostic Performance of MRI for Evaluation of Acute Appendicitis

OBJECTIVE

A meta-analysis was performed to determine the accuracy of MRI in the diagnosis of acute appendicitis in the general population and in subsets of pregnant patients and children.

MATERIALS AND METHODS

A systematic search of the PubMed and EMBASE databases for articles published through the end of October 2014 was performed to identify studies that used MRI to evaluate patients suspected of having acute appendicitis. Pooled data for sensitivity, specificity, and positive and negative predictive values were calculated.

RESULTS

A total of 30 studies that comprised 2665 patients were reviewed. The sensitivity and specificity of MRI for the diagnosis of acute appendicitis are 96% (95% CI, 95-97%) and 96% (95% CI, 95-97%), respectively. In a subgroup of studies that focused solely on pregnant patients, the sensitivity and specificity of MRI were 94% (95% CI, 87-98%) and 97% (95% CI, 96-98%), respectively, whereas in studies that focused on children, sensitivity and specificity were found to be 96% (95% CI, 95-97%) and 96% (95% CI, 94-98%), respectively.

CONCLUSION

MRI has a high accuracy for the diagnosis of acute appendicitis, for a wide range of patients, and may be acceptable for use as a first-line diagnostic test.

Lower Abdominal Pain

Although most frequently presenting with lower abdominal pain, appendicitis, colitis, and diverticulitis can cause pain throughout the abdomen and can cause peritoneal and retroperitoneal symptoms. Evaluation and management of lower intestinal disease requires a nuanced approach by the emergency physician, sometimes requiring computed tomography, ultrasonography, MRI, layered imaging, shared decision making, serial examination, and/or close follow-up. Once a presumed or confirmed diagnosis is made, appropriate treatment is initiated, and may include surgery, antibiotics, and/or steroids. Appendicitis patients should be admitted. Diverticulitis and inflammatory bowel disease can frequently be managed on an outpatient basis, but may require admission and surgical consultation.

Acute appendicitis in pregnancy: literature review

INTRODUCTION

suspected appendicitis is the most common indication for surgery in non-obstetric conditions during pregnancy and occurs in about one in 500 to one in 635 pregnancies per year. This occurs more often in the second trimester of pregnancy. Acute appendicitis is the most common general surgical problem encountered during pregnancy.

METHODS

a literature review on research of scientific articles, under the terms "acute appendicitis" and "pregnancy", in PubMed, Lilacs/SciELO, Scopus, Cochrane Library and Uptodate databases.

RESULTS

the clinical manifestations of appendicitis are similar to non-pregnant women, however, without a classic presentation, which often occurs, diagnosis is difficult and must be supported by imaging.

DISCUSSION

clinical diagnosis should be strongly suspected in pregnant women with classic findings such as abdominal pain that migrates to the right lower quadrant. The main purpose of imaging is to reduce delays in surgical intervention due to diagnostic uncertainty. A secondary objective is to reduce, but not eliminate, the negative appendectomy rate. Differential diagnosis of suspected acute appendicitis usually includes pathologies considered in non-pregnant people.

CONCLUSION

the imaging study of choice is ultrasound, MRI may be used when the former is not conclusive and, as a last resort, a CT scan can be performed. The treatment remains appendectomy by laparotomy, since the feasibility of video- assisted surgery in these cases remains controversial.

Abdominal emergencies during pregnancy

Abdominal emergencies during pregnancy (excluding obstetrical emergencies) occur in one out of 500-700 pregnancies and may involve gastrointestinal, gynecologic, urologic, vascular and traumatic etiologies; surgery is necessary in 0.2-2% of cases. Since these emergencies are relatively rare, patients should be referred to specialized centers where surgical, obstetrical and neonatal cares are available, particularly because surgical intervention increases the risk of premature labor. Clinical presentations may be atypical and misleading because of pregnancy-associated anatomical and physiologic alterations, which often result in diagnostic uncertainty and therapeutic delay with increased risks of maternal and infant morbidity. The most common abdominal emergencies are acute appendicitis (best treated by laparoscopic appendectomy), acute calculous cholecystitis (best treated by laparoscopic cholecystectomy from the first trimester through the early part of the third trimester) and intestinal obstruction (where medical treatment is the first-line approach, just as in the non-pregnant patient). Acute pancreatitis is rare, usually resulting from trans-ampullary passage of gallstones; it usually resolves with medical treatment but an elevated risk of recurrent episodes justifies laparoscopic cholecystectomy in the 2nd trimester and endoscopic sphincterotomy in the 3rd trimester. The aim of the present work is to review pregnancy-induced anatomical and physiological modifications, to describe the main abdominal emergencies during pregnancy, their specific features and their diagnostic and therapeutic management.

Diagnostic Imaging of Appendicitis With Supplementation by Transabdominal and Transvaginal Sonography

Acute appendicitis is a condition that can affect any member of the population. Without timely treatment there is a high likelihood of rupture leading to peritonitis, and early diagnosis is imperative to obtaining treatment. Sonography can be used without fear of radiation exposure to the patient and with relatively little discomfort, ideal for pediatric patients. It can also be used with little patient preparation, with the possibility of a more rapid diagnosis than other imaging modalities. For patients presenting with atypical symptoms, sonography may be used to increase diagnostic accuracy, which will lead to a drop in the surgical removal rate of a healthy appendix. When diagnostic criteria are met, sonography results can be correlated with the patient’s blood test and clinical symptoms to make a positive diagnosis. The addition of the transvaginal approach for female patients has further increased the rate of success of diagnosing acute appendicitis, so that appropriate emergent surgery can be done.

Optimizing diagnostic imaging in the emergency department

While emergency diagnostic imaging use has increased significantly, there is a lack of evidence for corresponding improvements in patient outcomes. Optimizing emergency department (ED) diagnostic imaging has the potential to improve the quality, safety, and outcomes of ED patients, but to date, there have not been any coordinated efforts to further our evidence-based knowledge in this area. The objective of this article is to discuss six aspects of diagnostic imaging to provide background information on the underlying framework for the 2015 Academic Emergency Medicine consensus conference, "Diagnostic Imaging in the Emergency Department: A Research Agenda to Optimize Utilization." The consensus conference aims to generate a high priority research agenda for emergency diagnostic imaging that will inform the design of future investigations. The six components herein will serve as the group topics for the conference: 1) patient-centered outcomes research; 2) clinical decision rules; 3) training, education, and competency; 4) knowledge translation and barriers to image optimization; 5) use of administrative data; and 6) comparative effectiveness research: alternatives to traditional CT use.

Single institution and statewide performance of ultrasound in diagnosing appendicitis in pregnancy

OBJECTIVE

Assess the performance of ultrasound (US) in pregnant patients presenting with acute abdominal pain concerning for appendicitis.

METHODS

Descriptive analysis of pregnant patients who underwent an US for acute abdominal pain over a 6-year period using data from a statewide quality improvement collaborative and a single center.

RESULTS

Statewide, 131 pregnant patients underwent an appendectomy and 85% had an US. In our single-center case series, 49 pregnant patients underwent an US for acute abdominal pain and four patients had appendicitis (8%). Of those, three were definitively diagnosed with US. The appendix was visualized by US in five patients (3 appendicitis/2 normal). Mean gestational age was 11 weeks for visualization of the appendix versus 20 weeks for non-visualization (p < 0.001). Concordance between US and pathology was similar statewide and at our institution (43%).

CONCLUSIONS

US appears to play a central role in the evaluation of appendicitis in pregnant women, especially in the first trimester, and often contributes to definitive disposition. US performed less well in excluding appendicitis; however, in certain clinical settings, providers appeared to trust US findings. From these results, we developed a multidisciplinary imaging pathway for pregnant patients who present with acute abdominal pain concerning for appendicitis.

A simple clinical decision rule to rule out appendicitis in patients with nondiagnostic ultrasound results

OBJECTIVES

The objective was to identify a set of clinical features that can rule out appendicitis in patients with suspected acute appendicitis and nondiagnostic ultrasound (US) results, allowing safe discharge and next-day reevaluation without initial computed tomography (CT) or magnetic resonance imaging (MRI).

METHODS

Data on clinical and US evaluation, including a number of prespecified variables potentially associated with acute appendicitis, were prospectively collected in two diagnostic accuracy studies of imaging. These studies included patients with suspected appendicitis seen in the emergency department (ED). For development and validation of the clinical decision rule (CDR), only patients with inconclusive or negative US results were included. There were 199 (of 422) patients in the development cohorts and 120 (of 211) patients in the validation cohort. Logistic regression analysis was used for data from patients with inconclusive or negative US results, and profiles were created of all possible combinations of predictors retained in the multivariable model. A final diagnosis was assigned by an expert panel based on perioperative data, histopathology, and clinical follow-up of at least 3 months.

RESULTS

The CDR selected patients after negative or inconclusive US for discharge and next-day reevaluation without initial CT or MRI if fewer than two of the following predictors were present: male sex, migration of pain to the right lower quadrant, vomiting, and white blood cell (WBC) count higher than 12.0 × 10(9) /L. Applying the CDR in the development set selected 126 of 199 (63%) patients with negative or inconclusive US results for discharge without further imaging. This rule reduced the probability of appendicitis from 26% (51 of 199) in the total group of patients with negative or inconclusive US results to 12% (15 of 126) in the group that would be discharged based on the rule (p = 0.001). In the validation set (n = 120), the decision rule selected 72 (60%) patients for discharge and next-day reevaluation and reduced the probability of appendicitis from 20% (24 of 120) in the total group to 6% (4 of 72) in the patients selected on the rule (p = 0.001). The negative predictive value of the decision rule in the validation set was 94% (95% confidence interval [CI] = 87% to 98%). In comparison, the negative predictive value of CT in the same group was 99% (95% CI = 93% to 100%, p = 0.14), and that of MRI was 99% (95% CI = 94% to 100%, p = 0.12). Alternative decision rules based on combinations of the present decision rule with C-reactive protein (CRP) results did not improve selection.

CONCLUSIONS

This newly developed CDR significantly reduces the probability of appendicitis in a large subgroup of patients with negative or inconclusive US results. These patients can be safely discharged for outpatient reevaluation without further initial imaging if proper follow-up is available. This could assist in lowering the number of ED imaging investigations in patients with suspected appendicitis.

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.

Cost-effectiveness of preoperative imaging for appendicitis after indeterminate ultrasonography in the second or third trimester of pregnancy

OBJECTIVE

To assess the cost-effectiveness of diagnostic laparoscopy, computed tomography (CT), and magnetic resonance imaging (MRI) after indeterminate ultrasonography in pregnant women with suspected appendicitis.

METHODS

A decision-analytic model was developed to simulate appendicitis during pregnancy taking into consideration the health outcomes for both the pregnant women and developing fetuses. Strategies included diagnostic laparoscopy, CT, and MRI. Outcomes included positive appendectomy, negative appendectomy, maternal perioperative complications, preterm delivery, fetal loss, childhood cancer, lifetime costs, discounted life expectancy, and incremental cost-effectiveness ratios.

RESULTS

Magnetic resonance imaging is the most cost-effective strategy, costing $6,767 per quality-adjusted life-year gained relative to CT, well below the generally accepted $50,000 per quality-adjusted life-year threshold. In a setting where MRI is unavailable, CT is cost-effective even when considering the increased risk of radiation-associated childhood cancer ($560 per quality-adjusted life-year gained relative to diagnostic laparoscopy). Unless the negative appendectomy rate is less than 1%, imaging of any type is more cost-effective than proceeding directly to diagnostic laparoscopy.

CONCLUSIONS

Depending on imaging costs and resource availability, both CT and MRI are potentially cost-effective. The risk of radiation-associated childhood cancer from CT has little effect on population-level outcomes or cost-effectiveness but is a concern for individual patients. For pregnant women with suspected appendicitis, an extremely high level of clinical diagnostic certainty must be reached before proceeding to operation without preoperative imaging.

A case of Hickam's dictum: concurrent appendicitis and ectopic pregnancy

BACKGROUND

Both ectopic pregnancy and appendicitis are surgical emergencies that should be considered in female patients who present with right lower-quadrant pain. Deciding on the appropriate imaging modality in the pregnant patient can be difficult. The challenge of diagnosis is compounded when one considers that both pathologies may be present simultaneously.

OBJECTIVES

We present a case demonstrating co-occurrence of ectopic pregnancy and appendicitis and suggest an algorithm for evaluation and management of cases with this presentation.

CASE REPORT

A 25-year-old woman presented to the Emergency Department complaining of 3 days of abdominal pain and a positive urine pregnancy test. After consultation with Obstetrics/Gynecology (OB/GYN) and General Surgery, a nondiagnostic pelvic ultrasound (US), and a magnetic resonance imaging (MRI) study consistent with appendiceal inflammation, the patient was taken to the operating room for a laparoscopic appendectomy. While removing the inflamed appendix, the general surgeon noted the right fallopian tube was enlarged, suggestive of an ectopic pregnancy. OB/GYN was consulted again intraoperatively and noted a right ectopic pregnancy. The surgical intervention was completed with a right salpingectomy.

CONCLUSION

In a pregnant patient with right lower-quadrant pain, the differential diagnosis includes ectopic pregnancy, acute appendicitis, or in rare cases, both.

The vermiform appendix: a review

New research on the vermiform appendix has shed light on its function. In further understanding the function of the appendix, this information should not negatively impact the clinical judgment in the event of appendicitis. Although the appendix and its pathology have been noted for centuries, it still presents a challenge in the operating room. The most common emergency surgical procedure performed is an appendectomy. Its highly variable position within the abdomen can cause confusion for clinicians. However, improved imaging modalities have heightened the physician's ability to diagnose disease of this organ. This article reviews germane literature regarding the human vermiform appendix.

Appendicitis: changing perspectives

Neoplasms are an uncommon finding after appendectomy, with malignant tumors occurring in less than 1% of the surgical specimens, and carcinoid being the most frequent malignancy. A negative or inconclusive ultrasound is not adequate to rule out appendicitis and should be followed by CT scan. For pregnant patients, MRI is a reasonable alternative to CT scan. Nonoperative treatment with antibiotics is safe as an initial treatment of uncomplicated appendicitis, with a significant decrease in complications but a high failure rate. Open and laparoscopic appendectomies for appendicitis provide similar results overall, although the laparoscopic technique may be advantageous for obese and elderly patients but may be associated with a higher incidence of intraabdominal abscess. Preoperative diagnostic accuracy is of utmost importance during pregnancy because a negative appendectomy is associated with a significant incidence of fetal loss. The increased morbidity associated with appendectomy delay suggests that prompt surgical intervention remains the safest approach. Routine incidental appendectomy should not be performed except in selected cases. Interval appendectomy is not indicated because of considerable risks of complications and lack of any clinical benefit. Patients older than 40 years with an appendiceal mass or abscess treated nonoperatively should routinely have a colonoscopy as part of their follow-up to rule out cancer or alternative diagnosis.

APPENDICITIS IN PREGNANCY

Acute appendicitis is the most common non-obstetric indication for surgical intervention in pregnancy, complicating 1/500 to 1/2000 deliveries. Due to the anatomical and physiological changes associated with pregnancy, appendicitis may present a diagnostic dilemma, leading to management delays and thus increasing the risk of appendiceal perforation. Many of the common presenting symptoms of appendicitis are common features of normal pregnancy including lower abdominal pain, nausea, vomiting and leukocytosis. Furthermore, the enlarging gravid uterus may displace the appendix to varying degrees thus altering the classic symptom pattern of appendicitis. The often nonspecific presentation in pregnancy may necessitate the utilization of diagnostic imaging to aid in accurate diagnosis. However, the perforated appendix is the most common surgical cause of fetal loss and the time required for any diagnostic aid must be weighed against the increasing risk of perforation caused by delay in surgical intervention.

Severe sepsis and septic shock in pregnancy

Pregnancies complicated by severe sepsis and septic shock are associated with increased rates of preterm labor, fetal infection, and preterm delivery. Sepsis onset in pregnancy can be insidious, and patients may appear deceptively well before rapidly deteriorating with the development of septic shock, multiple organ dysfunction syndrome, or death. The outcome and survivability in severe sepsis and septic shock in pregnancy are improved with early detection, prompt recognition of the source of infection, and targeted therapy. This improvement can be achieved by formulating a stepwise approach that consists of early provision of time-sensitive interventions such as: aggressive hydration (20 mL/kg of normal saline over the first hour), initiation of appropriate empiric intravenous antibiotics (gentamicin, clindamycin, and penicillin) within 1 hour of diagnosis, central hemodynamic monitoring, and the involvement of infectious disease specialists and critical care specialists familiar with the physiologic changes in pregnancy. Thorough physical examination and imaging techniques or empiric exploratory laparotomy are suggested to identify the septic source. Even with appropriate antibiotic therapy, patients may continue to deteriorate unless septic foci (ie, abscess, necrotic tissue) are surgically excised. The decision for delivery in the setting of antepartum severe sepsis or septic shock can be challenging but must be based on gestational age, maternal status, and fetal status. The natural inclination is to proceed with emergent delivery for a concerning fetal status, but it is imperative to stabilize the mother first, because in doing so the fetal status will likewise improve. Aggressive [corrected] treatment of sepsis can be expected to reduce the progression to severe sepsis and septic shock and prevention strategies can include preoperative skin preparations and prophylactic antibiotic therapy as well as appropriate immunizations.

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.

Utility of ultrasound for evaluating the appendix during the second and third trimester of pregnancy

This study aims to retrospectively evaluate the right lower quadrant ultrasounds in women presenting during the second or third trimester of pregnancy for the frequency of appendix visualization and accuracy in diagnosing appendicitis. Institutional Review Board approval was obtained for this Health Insurance Portability and Accountability Act-compliant study. We reviewed imaging records from 99 consecutive pregnant women from 2001 to 2011 who presented during the second (≥14 weeks gestation) or third trimester for right lower quadrant ultrasound to evaluate the appendix. Visualization of the appendix as well as the size and compressibility, if identified, were recorded. The medical records and labs related to the initial patient presentation, subsequent management, and follow-up were reviewed for surgical and clinical outcomes. Pathology records were reviewed to determine if appendicitis was present when appendectomy was performed. Patients who underwent appendectomy were considered to have appendicitis based on pathology results, and patients managed non-operatively with symptom improvement and those with a normal appendix at pathology were considered to not have appendicitis. During the study period, 99 women meeting inclusion criteria presented to our institution for right lower quadrant ultrasound to evaluate the appendix during the second or third trimester of pregnancy. The mean gestational age at presentation was 23 weeks (±7 weeks). The mean maternal age was 28 years (±6.6 years). The appendix was not visualized in 97% (96/99) of right lower quadrant ultrasound examinations. Of the three studies in which the appendix was visualized, two were considered positive for appendicitis and one was considered negative. Eight patients in this group ultimately underwent appendectomy, including the two patients with positive right lower quadrant ultrasounds, and appendicitis confirmed at pathology in seven of these cases (87.5%). Right lower quadrant ultrasound successfully demonstrated an abnormal appendix in 28.7% (two of seven) of surgically confirmed cases; however, this technique did not detect appendicitis in 71% (five of seven) of patients with surgically proven disease due to nonvisualization of the appendix. Retrospective review of right lower quadrant ultrasounds performed during the second and third trimester of pregnancy suggests that this modality has limited utility for diagnosing appendicitis due to infrequent visualization of the appendix.

Imaging acute appendicitis: state of the art

The goal of this review is to present the state of the art in imaging tests for the diagnosis of acute appendicitis. Relevant publications regarding performance and advantages/disadvantages of imaging modalities for the diagnosis of appendicitis in different clinical situations were reviewed. Articles were extracted from a computerized database (MEDLINE) with the following activated limits: Humans, English, core clinical journals, and published in the last five years. Reference lists of relevant studies were checked manually to identify additional, related articles. Ultrasound (US) examination should be the first imaging test performed, particularly among the pediatric and young adult populations, who represent the main targets for appendicitis, as well as in pregnant patients. A positive US examination for appendicitis or an alternative diagnosis of possible gastrointestinal or urological origin, or a negative US, either showing a normal appendix or presenting low clinical suspicion of appendicitis, should lead to a final diagnosis. A negative or indeterminate examination with a strong clinical suspicion of appendicitis should be followed by a computed tomography (CT) scan or alternatively, a magnetic resonanace imaging (MRI) scan in a pregnant patient. A second US examination in a patient with persistent symptoms, especially if the first one was performed by a less experienced imaging professional, is a valid alternative to a CT.

Gastrointestinal Conditions during Pregnancy

Pregnancy causes anatomic and physiologic changes in the gastrointestinal tract. Pregnant women with intestinal disease such as Crohn disease or ulcerative colitis pose a management challenge in clinical diagnosis, radiologic evaluation, and treatment secondary to potential risk to the fetus. Heightened physician awareness on possible etiologies such as appendicitis, diverticulitis, and rarely colorectal cancer is required for rapid diagnosis and treatment to improve maternal/fetal outcome. A multidisciplinary approach to evaluation is a necessity because radiologic procedures and treatment medications commonly used in nonpregnant patients may have a potential harmful effect on the fetus. The authors review several gastrointestinal conditions encountered during pregnancy and address presentation, diagnosis, and treatment of each condition.

Accuracy of sonography in diagnosis of acute appendicitis running

This study was conducted to assess the efficacy of ultrasound in the diagnosis of acute appendicitis in clinically suspected cases of acute appendicitis. A total of 110 patients clinically suspected to have acute appendicitis admitted to the surgery departments of Golestan and Imam Khomeini hospitals, from March 2006 to 2007. Abdomino-pelvic ultrasonography with focus on RLQ ultrasonographying the graded compression technique was done. Positive ultrasonography was defined as at least one of the criteria of puylaert. The sonographic data were prospectively correlated with clinical, operative and pathological findings. Graded compression ultrasonography results were analyzed and remarked 92.7% sensitivity, 94.5% specificity, 93% accuracy, 94.4% positive predictive value and 92.5% negative predictive value. Ultrasonography is an accurate, safe and reliable method in the diagnosis of suspected cases of acute appendicitis that can help to minimize negative appendectomies and perforation rates.