CT Evaluation of Appendicitis and Its Complications: Imaging Techniques and Key Diagnostic Findings

Pediatric appendicitis with appendicolith often presents with prolonged abdominal pain and a high risk of perforation

BACKGROUND

Appendicolith can cause appendiceal obstruction and acute appendicitis. Its high prevalence may be related to the high perforation rate in pediatric appendicitis. This study assessed the characteristics of appendicolith and its clinical significance in pediatric appendicitis.

METHODS

A retrospective study was performed among children and adolescents younger than 17 years who were preoperatively diagnosed with appendicitis in the pediatric emergency department (ED). A total of 269 patients with a mean age of 9.98 ± 3.37 years were enrolled. Clinical features and contrast-enhanced computed tomography findings were analyzed.

RESULTS

Among the 269 patients, 147 (54.6%) had appendicoliths, with a mean maximal diameter of 5.21 ± 2.34 mm. Compared to the no appendicolith group, the appendicolith group demonstrated more prolonged abdominal pain (≥ 48 hours) before the ED visit (23.1% vs. 11.5%; P = 0.013), clinical features of severe appendicitis (presence of fever, vomiting, positive urine ketone, and increased C-reactive protein), and higher rate of perforation (43.5% vs. 9.8%; P < 0.001). Multivariate risk factor analysis for perforated appendicitis in the appendicolith group revealed that maximal diameter of 5 mm or more in the appendicolith (adjusted odds ratio [aOR] 2.919; 95% CI 1.325-6.428, P = 0.008) and proximal collapse adjacent to the appendicolith (aOR 2.943; 95% CI 1.344-6.443, P = 0.007) were significant.

CONCLUSIONS

Pediatric appendicitis with appendicolith often presents with prolonged abdominal pain and severe clinical conditions with a high risk of perforation.

Diagnostic Efficiency of Multidetector Computed Tomography in the Evaluation of Clinically Equivocal Cases of Acute Appendicitis with Surgical Correlation

Acute appendicitis is one of the most frequent causes of lower abdominal pain and requires immediate surgical intervention. The diagnosis often poses a lot of challenge even to experienced surgeon. Those patients with equivocal symptoms may require different imaging modalities like radiography, contrast examination and ultrasound with limited utility. Multidetector computed tomography (MDCT) used in suspected acute appendicitis has, however, resulted in improved diagnostic accuracy and also reduction of negative surgeries. Objective We intend to determine the diagnostic efficiency of MDCT in clinically equivocal cases of acute appendicitis correlating it with surgical/histopathological findings. Materials and methods A group of 116 patients was included in this study. Spiral MDCT was performed in all these cases after administration of oral and intravenous contrast. All these patients underwent surgery and the CT findings were correlated with histopathology. Out of these 116 patients, 60 patients were male and 56 female. The age range was from three to seventy years and mean age was 28+1 years. Results The results proved that MDCT had a sensitivity of 97.5%, specificity of 97.0%, and accuracy of 97.4% for the diagnosis of appendicitis with one false positive and two false negative cases. The study showed 100% accuracy in diagnosing acute appendicitis in children. In 33 patients, an alternate cause was identified with CT. The alternate diagnosis made on CT findings was consistent with the final diagnosis in 27 (81.8%) of 33 patients in whom there was no evidence of acute appendicitis. The clinical diagnosis disagreed with the CT diagnosis in six patients (18.18%). Conclusion Our study verifies that MDCT plays an important role in evaluation and consequent management of equivocal cases of acute appendicitis. MDCT is also able to diagnose appendicitis or detect alternative diagnosis in pediatric population.

Efficacy of Strain Elastography in Diagnosis and Staging of Acute Appendicitis in Pediatric Patients

Background

In the present study, the role and efficiency of strain elastography (SE) were evaluated in diagnosis and staging of acute appendicitis in pediatric patients.

Material/Methods

We enrolled 225 pediatric patients with suspected clinical and laboratory findings of acute appendicitis. Gray-scale sonographic findings were recorded and staging was made by the colorization method of SE imaging. Appendectomy was performed in all patients and the results of the surgical pathology were compared with the imaging findings. The sensitivity, specificity, and accuracy of SE imaging were determined in terms of evaluating the “acute appendicitis”.

Results

Sonographic evaluation revealed acute appendicitis in 100 patients. Regarding the SE analysis, cases with appendicitis were classified into 3 groups as: mild (n=17), moderate (n=39), and severe (n=44). The pathological evaluation revealed 95 different stages of appendicitis and normal appendix in 5 cases: acute focal (n=10), acute suppurative (n=46), phlegmonous (n=27), and perforated (n=12), regarding the results of surgical pathology. Five patients with pathologically proven “normal” appendix were noted as “mild stage appendicitis” based on gray scale and SE analysis. In total, when gray-scale and SE results were compared with pathology results regardless of the stage of appendicitis, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy rates were 96%, 96%, 95%, 96.8%, and 96%, respectively. No statistically significant difference was detected between other groups (P<0.05).

Conclusions

In acute appendicitis, the use of SE imaging as a supportive method for the clinical approach can be useful in diagnosis, and its results are closely correlated with the histopathologic stage of appendix inflammation.

Prospective Observational Study on acute Appendicitis Worldwide (POSAW)

BACKGROUND

Acute appendicitis (AA) is the most common surgical disease, and appendectomy is the treatment of choice in the majority of cases. A correct diagnosis is key for decreasing the negative appendectomy rate. The management can become difficult in case of complicated appendicitis. The aim of this study is to describe the worldwide clinical and diagnostic work-up and management of AA in surgical departments.

METHODS

This prospective multicenter observational study was performed in 116 worldwide surgical departments from 44 countries over a 6-month period (April 1, 2016-September 30, 2016). All consecutive patients admitted to surgical departments with a clinical diagnosis of AA were included in the study.

RESULTS

A total of 4282 patients were enrolled in the POSAW study, 1928 (45%) women and 2354 (55%) men, with a median age of 29 years. Nine hundred and seven (21.2%) patients underwent an abdominal CT scan, 1856 (43.3%) patients an US, and 285 (6.7%) patients both CT scan and US. A total of 4097 (95.7%) patients underwent surgery; 1809 (42.2%) underwent open appendectomy and 2215 (51.7%) had laparoscopic appendectomy. One hundred eighty-five (4.3%) patients were managed conservatively. Major complications occurred in 199 patients (4.6%). The overall mortality rate was 0.28%.

CONCLUSIONS

The results of the present study confirm the clinical value of imaging techniques and prognostic scores. Appendectomy remains the most effective treatment of acute appendicitis. Mortality rate is low.

Diagnosis of Acute Appendicitis Using Clinical Alvarado Scoring System and Computed Tomography (CT) Criteria in Patients Attending Gujarat Adani Institute of Medical Science - A Retrospective Study

Background

The aim was to evaluate the clinical Alvarado scoring system and computed tomography (CT) criteria for the diagnosis of acute appendicitis.

Material/Methods

The study was carried out retrospectively in patients who were referred to the Institute between March 2014 and January 2015. One hundred seventeen patients with acute abdominal pain who underwent abdominal CT were enrolled in this retrospective study. Patient demographics, clinical Alvarado scoring, CT images, and pathologic results of the patients were evaluated.

Results

Thirty nine of the 53 patients who were operated on had pathologically proven acute appendicitis. CT criteria of appendiceal diameter, presence of periappendiceal inflammation, fluid, appendicoliths, and white blood cell count (WBC) were significantly correlated with the inflammation of the appendix. The optimal cut-off value of the appendiceal diameter was 6.5 mm. The correlation between appendiceal diameter and WBC was 80% (P=0.01 <0.05). The correlation between appendiceal diameter and Alvarado score was 78.7% (P=0.01 <0.05).

Conclusions

Presence of appendiceal diameter above 6.5 mm on CT, periappendiceal inflammation, fluid, and appendicoliths should prompt the diagnosis of acute appendicitis. Since patients with acute appendicitis may not always show the typical signs and symptoms, CT is a helpful imaging modality for patients with relatively low Alvarado scores and leukocytosis, when physical examination is confusing.

Successful nonoperative management of uncomplicated appendicitis: predictors and outcomes

BACKGROUND

Our objective was to identify predictors of successful nonoperative management (NOM) of uncomplicated appendicitis. We hypothesized that the absence of diabetes, absence of an appendicolith, short duration of symptoms, absence of systemic inflammation, and low modified Alvarado score would predict successful NOM.

METHODS

We performed a retrospective cohort analysis of 81 consecutive patients who underwent NOM of uncomplicated appendicitis. Successful NOM was defined as resolution of appendicitis with antibiotics alone and no recurrent appendicitis within 180 days. Patients with successful NOM (n = 36) were compared with patients who failed NOM (n = 45). Multivariable logistic regression was used to identify predictors of successful NOM, expressed as odds ratios (ORs) with 95% confidence intervals. Model strength was assessed by calculating area under the receiver operating characteristic curve (AUC).

RESULTS

Patient age (35 years), the American Society of Anesthesiologists class (2.0), and Charlson comorbidity index (0.0) were similar between groups. Independent predictors of successful NOM were duration of symptoms prior to admission >25 hours: OR 4.17 (1.42-12.24), maximum temperature within 6 hours of admission <37.3°C: OR 8.07 (1.79-36.38), modified Alvarado score <4: OR 9.06 (1.26-64.93), and appendiceal diameter <13 mm: OR 17.55 (1.30-237.28); model AUC: 0.81 (0.72-0.90).

CONCLUSIONS

Patients with a longer duration of symptoms prior to admission were more likely to have successful NOM. Other independent predictors of successful NOM included lower temperature, lower modified Alvarado score, and smaller appendiceal diameter. These findings provide a framework for clinical decision-making and large-scale derivation and validation of a model to predict successful NOM of uncomplicated appendicitis.

CT guided appendicectomy incision: A prospective case series

OBJECTIVE

Several radiological studies have suggested that the base of the Appendix often does not correspond with Mc Burney's point. The aim of our study is to assess the value of using CT localization of the appendicocaecal junction to guide placement of the appendicectomy incision.

DESIGN & METHOD

32 consecutive patients, booked for open appendicectomy were prospectively included in this study. Coronal and axial CT scans with IV contrast were studied to assess site of the appendicocaecal junction. This information was used to guide placement of the incision.

RESULTS

28 out of 32 patients studied, the appendicocaecal junctions were accurately identified. It was noted that the final incision sites were cephalad to Mc Burney's point in 8, at the point in 3 and caudal in 17. In 1 patient, it was necessary to extend the incision medially by 2cm to retrieve the distal Appendix which had been detached through the site of rupture.

CONCLUSION

Mc Burney's point often does not correspond to the base of the appendix. We propose that using CT imaging to guide the appendicectomy incision is safe, facilitates locating the Appendix at surgery, minimizes incision size and decreases the need to extend it.

Can clinical scoring systems improve the diagnostic accuracy in patients with suspected adult appendicitis and equivocal preoperative computed tomography findings?

Objective

Adult appendicitis (AA) with equivocal computed tomography (CT) findings remains a diagnostic challenge for physicians. Herein we evaluated the diagnostic performance of several clinical scoring systems in adult patients with suspected appendicitis and equivocal CT findings.

Methods

We retrospectively evaluated 189 adult patients with equivocal CT findings. Alvarado, Eskelinen, appendicitis inflammatory response, Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA), and adult appendicitis score (AAS) scores were evaluated, receiver operating characteristic analysis was conducted, and the optimal, low, and high cut-off values were determined for patient classification into three groups: low, intermediate, or high.

Results

In total, 61 patients were included in the appendicitis group and 128 in the non-appendicitis group. There were no significant differences between the area under the curve of the clinical scoring systems in the final diagnosis of AA for equivocal appendicitis on CT (Alvarado, 0.698; Eskelinen, 0.710; appendicitis inflammatory response, 0.668; RIPASA, 0.653; AAS, 0.726). A RIPASA score greater than 7.5 had a high positive predictive value (90.9) and an AAS score less than or equal to 5 had a high negative predictive value (91.7) in the diagnosis of AA.

Conclusion

The accuracy of clinical scoring systems in the diagnosis of AA with equivocal CT findings was moderate. Therefore, a high RIPASA score may assist in the diagnosis of AA in patients with equivocal CT findings, and a low AAS score may be used as a criterion for patient discharge. Most patients presented with intermediate scores. The patients with equivocal CT findings may be considered as a third diagnostic category of AA.

Acute Bowel Computed Tomography

Acute abdominal pain is a common presenting complaint in the emergency department. Increasingly, computed tomography is utilized for evaluating these patients. Radiologists are therefore expected to be familiar with the pertinent clinical and radiologic information related to acute bowel pathology. This primer will review the need-to-know and latest updates related to computed tomography evaluation of acute bowel pathology.

Predicting appendiceal tumors among patients with appendicitis

BACKGROUND

As nonoperative management of appendicitis gains popularity, vigilance for appendiceal tumors becomes increasingly important. We hypothesized that, among patients presenting with acute appendicitis, those with advanced age, multiple comorbidities, atypical presentation, and complicated appendicitis would be more likely to have underlying appendiceal tumors.

METHODS

We performed a 4-year retrospective cohort analysis of 677 consecutive adult patients who underwent appendectomy for appendicitis at our tertiary care center. Patients with an appendiceal tumor on their final pathology report were compared to patients with no tumor. Conditions present on admission were used to create a multivariate logistic regression model to predict appendiceal tumor. Risk factors were reported as odds ratio (OR) [95% CI]. Model strength was assessed by area under the receiver operating characteristic curve.

RESULTS

Seventeen patients (2.5%) had an appendiceal tumor. Within this group. 14 underwent immediate appendectomy, two initially had nonoperative management but failed to improve on antibiotics and underwent appendectomy during the initial admission, and one had successful nonoperative management and elective appendectomy 19 days after discharge. Four variables contributed to the multivariate model to predict the presence appendiceal tumor: age ≥ 50 (OR 3.6 [1.1-11.4]), outpatient steroid/immunosuppressant use (OR 12.1 [2.0-72.5]), the absence of migratory right lower quadrant pain (OR 4.7 [1.2-18.1]), and the appearance of a phlegmon on CT scan (OR 7.0 [1.6-30.2]); model area under the receiver operating characteristic curve: 0.860 [0.705-0.969].

CONCLUSION

For patients presenting with acute appendicitis, conditions present on admission may predict underlying appendiceal tumor. Patients with advanced age, multiple comorbidities, atypical presentation, and complicated appendicitis should be considered for appendectomy during the index admission or at earliest convenience if nonoperative management is necessary.

LEVEL OF EVIDENCE

Prognostic study, level III.

Antibiotics vs. Appendectomy for Acute Uncomplicated Appendicitis in Adults: Review of the Evidence and Future Directions

BACKGROUND

Acute appendicitis is the most common abdominal surgical emergency in the United States, with a lifetime risk of 7%-8%. The treatment paradigm for complicated appendicitis has evolved over the past decade, and many cases now are managed by broad-spectrum antibiotics. We determined the role of non-operative and operative management in adult patients with uncomplicated appendicitis.

METHODS

Several meta-analyses have attempted to clarify the debate. Arguably the most influential is the Appendicitis Acuta (APPAC) Trial.

RESULTS

According to the non-inferiority analysis and a pre-specified non-inferiority margin of -24%, the APPAC did not demonstrate non-inferiority of antibiotics vs. appendectomy. Significantly, however, the operations were nearly always open, whereas the majority of appendectomies in the United States are done laparoscopically; and laparoscopic and open appendectomies are not equivalent operations. Treatment with antibiotics is efficacious more than 70% of the time. However, a switch to an antimicrobial-only approach may result in a greater probability of antimicrobial-associated collateral damage, both to the host patient and to antibiotic susceptibility patterns. A surgery-only approach would result in a reduction in antibiotic exposure, a consideration in these days of focus on antimicrobial stewardship.

CONCLUSION

Future studies should focus on isolating the characteristics of appendicitis most susceptible to antibiotics, using laparoscopic operations as controls and identifying long-term side effects such as antibiotic resistance or Clostridium difficile colitis.

Ultrasound, computed tomography or magnetic resonance imaging - which is preferred for acute appendicitis in children? A Meta-analysis

BACKGROUND

There is no established consensus about the relative accuracies of US, CT and MRI in childhood appendicitis.

OBJECTIVE

To compare, through meta-analysis, the accuracies of US, CT and MRI for clinically suspected acute appendicitis in children.

MATERIALS AND METHODS

PubMed, Embase, Web of Science and the Cochrane Library were searched. After study selection, data extraction and quality assessment, the sensitivity, specificity and the area under the curve of summary receiver operating characteristic were calculated and compared.

RESULTS

Twenty-seven articles including 29 studies met the inclusion criteria, including 19 studies (9,170 patients) of US, 6 studies (928 patients) of CT and 4 studies (990 patients) of MRI. The analysis showed that the area under the receiver operator characteristics curve of MRI (0.995) was a little higher than that of US (0.987) and CT (0.982; P > 0.05).

CONCLUSION

US, CT and MRI have high diagnostic accuracies of clinically suspected acute appendicitis in children overall with no significant difference.

Ischemia-modified albumin as a predictor of the severity of acute appendicitis

BACKGROUND

The early prediction of gangrenous/perforated appendicitis is of great importance for the surgical planning, further treatments, and predicting the course of disease. Ischemia-modified albumin (IMA) was previously reported as a biomarker of various ischemia-based diseases. Our aim is to determine the predictive value of serum IMA in the severity of acute appendicitis.

METHODS

Sixty-two patients who underwent urgent appendectomy were included in the study. Plasma level of IMA was measured after diagnosis and before treatment. All patients were classified as noncomplicated (acute) appendicitis and complicated (gangrenous/perforated) appendicitis according to histopathological findings, and comparisons were made between the groups.

RESULTS

The data of 62 patients with a mean age of 30.1 years were statistically evaluated. The pathological diagnoses were acute appendicitis in 33 (53.2%), and gangrenous/perforated appendicitis in 29 (46.8%) patients. There were significant differences in computed tomography (CT) findings (P = .031) and IMA (P = .012) levels between the groups. A strong positive correlation between IMA levels and CT findings was also found (Spearman ρ = +0.688, P = .003).

CONCLUSIONS

The IMA can be considered as a novel and useful marker to distinguish gangrenous/perforated appendicitis from noncomplicated appendicitis. The correlation of IMA with CT findings also enhances the predictive value of IMA.

Contribution of diffusion-weighted MR imaging in follow-up of inflammatory appendiceal mass: Preliminary results and review of the literature

Objective

We aimed to search the contribution of diffusion-weighted imaging (DWI) in follow-up of patients with acute appendicitis associated inflammatory appendiceal mass (IAM). DWI was used as a monitoring imaging method to assess the response of medical treatment.

Materials and methods

19 patients (mean age, 37+–13.1; age range, 19–69; M/F: 10/9), presented with clinical, laboratory and computed tomography (CT) findings suggestive of IAM were enrolled prospectively in this study. CT and DWI images were evaluated by two radiologists in consensus. b values 0, 500 and 1000 s/mm² were used, and DWI images were analysed both qualitatively and quantitatively. Laboratory parameters were C-reactive protein value and white blood cell count. During follow-up changes in the diameter of IMA and laboratory parameters were correlated with ADC values. Conservative treatment with interval appendectomy and a total conservative approach without surgery were the treatment options during follow-up.

Results

We found statistically significant correlation between the ADC values, maximum IAM diameter and laboratory parameters. During follow-up five surgical procedures were performed: one patient underwent surgery for cecal adenocarcinoma and four underwent interval appendectomy. One patient developed acute relapse of IAM at the sixth month of follow-up.

Conclusion

DWI may be used with a significant success for follow-up of patients with IAM. As a monitoring imaging method, DWI may also aid in determining of most appropriate timing for interval appendectomy as well as may help in diagnosing alternative diagnoses (e.g. malignancy and inflammatory bowel disease) that can mimic IAM.

Pre-operative CT predictors associated with 30-day adverse events in patients with appendiceal inflammatory masses who underwent immediate appendectomies

PURPOSE

To retrospectively evaluate pre-operative CT predictors that are associated with 30-day adverse events in patients who underwent immediate appendectomies for appendiceal inflammatory masses.

METHODS

This retrospective study was approved by our institutional review board, and the requirement for informed consent was waived. One hundred forty-four consecutive patients who underwent immediate appendectomies and were diagnosed with appendiceal inflammatory masses by pre-operative CT from January 2005 to December 2013 at a tertiary hospital were included. The main outcome measure was 30-day adverse events. Patient demographics and data for inflammatory markers including leukocyte counts, segmented neutrophils, and C-reactive protein levels were collected by a single radiologist. Pre- and post-operative CT findings were evaluated for features of appendiceal inflammatory masses, associated findings, and post-operative adverse events by two radiologists in a blinded fashion with consensus to assess surgical and pathologic results, post-operative outcomes, and original CT interpretations. Appendiceal inflammatory masses were defined as complicated appendicitis with a phlegmon or an abscess that was identified on pre-operative CT exam. Factors associated with 30-day adverse events were assessed using logistic regression analysis.

RESULTS

A total of 22 (15%) of the 144 patients (mean age [±SD] 44.6 ± 22.0 years, range 3-97 years) experienced 30-day adverse events: ten intra-abdominal abscesses, three wound infections, two cases of peritonitis, two small bowel obstructions, two intra-abdominal abscesses with peritonitis, one intra-abdominal abscess with wound infection, one intra-abdominal abscess with small bowel obstruction, and one case of peritonitis with small bowel obstruction. In univariate analysis, the presence of appendicolith (odds ratio [OR] 2.49, p = 0.048) and high-grade obstruction (OR 3.79; p = 0.01) were associated with adverse events. High-grade obstruction (adjusted OR 3.05; p = 0.04) was the only independent pre-operative predictor associated with 30-day adverse events in patients with appendiceal inflammatory masses.

CONCLUSIONS

High-grade obstruction was an independent pre-operative CT predictor associated with 30-day adverse events in patients who underwent immediate appendectomies for appendiceal inflammatory masses.

Evaluation of Clinical Alvarado Scoring System and CT Criteria in the Diagnosis of Acute Appendicitis

Aim. The aim was to evaluate the clinical Alvarado scoring system and computed tomography (CT) criteria for the diagnosis of acute appendicitis. Material and Methods. 117 patients with acute abdominal pain who underwent abdominal CT were enrolled in this retrospective study. Patient demographics, clinical Alvarado scoring, CT images, and pathologic results of the patients were evaluated. Results. 39 of the 53 patients who were operated on had pathologically proven acute appendicitis. CT criteria of appendiceal diameter, presence of periappendiceal inflammation, fluid, appendicolith, and white blood cell (WBC) count were significantly correlated with the inflammation of the appendix. The best cut-off value for appendiceal diameter was 6.5 mm. The correlation between appendiceal diameter and WBC count was 80% (P = 0.01 < 0.05). The correlation between appendiceal diameter and Alvarado score was 78.7% (P = 0.01 < 0.05). Conclusion. Presence of CT criteria of appendiceal diameter above 6.5 mm, periappendiceal inflammation, fluid, and appendicolith should prompt the diagnosis of acute appendicitis. Since patients with acute appendicitis may not always show the typical signs and symptoms, CT is a helpful imaging modality for patients with relatively low Alvarado score and leukocytosis and when physical examination is confusing.

A 25-year-old male with appendicular agenesis: A case report and literature review

Congenital agenesis or absence of vermiform appendix is extremely rare. This case report entails a 25-year-old male who developed symptoms and signs of acute appendicitis. Despite an extensive surgical exploration, the vermiform appendix could not be found. The postoperative investigation did not reveal any abnormality, and the patient was diagnosed as a case of nonspecific abdominal pain (NSAP) and appendicular agenesis.

Hollow organ abdominal ischemia, part II: clinical features, etiology, imaging findings and management

Acute hollow organ ischemia commonly presents with acute pain prompting radiologic evaluation and almost always requires urgent treatment. Despite different risk factors and anatomic differences, ischemia is commonly due to low flow states but can also be due to arterial and venous occlusion. Radiologic diagnosis is critical as many present with nonspecific symptoms. Contrast-enhanced computed tomography (CT) is the modality of choice. Magnetic resonance imaging (MRI) is preferred in suspected appendicitis in pregnant patients and is superior in biliary necrosis. This article provides a pictorial review of the CT/MRI features of hollow abdominal organ ischemia while highlighting key clinical features, pathogenesis, and management.

Treatment Modalities and Antimicrobial Stewardship Initiatives in the Management of Intra-Abdominal Infections

Antimicrobial stewardship programs (ASPs) focus on improving the utilization of broad spectrum antibiotics to decrease the incidence of multidrug-resistant Gram positive and Gram negative pathogens. Hospital admission for both medical and surgical intra-abdominal infections (IAIs) commonly results in the empiric use of broad spectrum antibiotics such as fluoroquinolones, beta-lactam beta-lactamase inhibitors, and carbapenems that can select for resistant organisms. This review will discuss the management of uncomplicated and complicated IAIs as well as highlight stewardship initiatives focusing on the proper use of broad spectrum antibiotics.

Intra-Appendiceal Air at CT: Is It a Useful or a Confusing Sign for the Diagnosis of Acute Appendicitis?

Objective

To investigate the significance of intra-appendiceal air at CT for the evaluation of appendicitis.

Materials and Methods

We retrospectively analyzed 458 patients (216 men, 242 women; age range, 18-91 years) who underwent CT for suspected appendicitis. Two independent readers reviewed the CT. Prevalence, amount, and appearance of intra-appendiceal air were assessed and compared between the patients with and without appendicitis. Performance of CT diagnosis was evaluated in two reading strategies: once ignoring appendiceal air (strategy 1), and the other time considering presence of appendiceal air as indicative of no appendicitis in otherwise indeterminate cases (strategy 2), using receiver operating characteristic (ROC) analysis.

Results

Of the 458 patients, 102 had confirmed appendicitis. The prevalence of intra-appendiceal air was significantly different between patients with (13.2%) and without (79.8%) appendicitis (p < 0.001). The amount of appendiceal air was significantly lesser in patients having appendicitis as compared with the normal group, for both reader 1 (p = 0.011) and reader 2 (p = 0.002). Stool-like appearance and air-fluid levels were more common in the appendicitis group than in the normal appendix for both readers (p < 0.05). Areas under the ROC curves were not significantly different between strategies 1 and 2 in reader 1 (0.971 vs. 0.985, respectively; p = 0.056), but showed a small difference in reader 2 (0.969 vs. 0.986, respectively; p = 0.042).

Conclusion

Although significant differences were seen in the prevalence, amount, and appearance of intra-appendiceal air between patients with and without appendicitis, it has a limited incremental value for the diagnosis of acute appendicitis.

Initial Performance of Radiologists and Radiology Residents in Interpreting Low-Dose (2-mSv) Appendiceal CT

OBJECTIVE

The objective of our study was to prospectively evaluate the initial diagnostic performance and learning curve of a community of radiologists and residents in interpreting 2-mSv appendiceal CT.

SUBJECTS AND METHODS

We included 46 attending radiologists and 153 radiology residents from 22 hospitals who completed an online training course of 30 2-mSv CT cases. Appendicitis was confirmed in 14 cases. Most of the readers had limited (≤ 10 cases, n = 32) or no (n = 118) prior experience with low-dose appendiceal CT. The order of cases was randomized for each reader. A multireader multicase ROC analysis was performed. Generalized estimating equations were used to model the learning curves in diagnostic performance.

RESULTS

Diagnostic performance gradually improved with years of training. The average AUC was 0.94 (95% CI, 0.90-0.98), 0.92 (0.88-0.96), 0.90 (0.85-0.96), and 0.86 (0.80-0.92) for the attending radiologists, senior residents, 2nd-year residents, and 1st-year residents, respectively. We did not observe any notable intrareader learning curves over the training course of the 30 cases except a decrease in reading time. Diagnostic accuracy and sensitivity were significantly affected by the reader training level and prior overall experience with appendiceal CT but not by the prior specific experience with low-dose appendiceal CT.

CONCLUSION

The learning curve is likely prolonged and forms gradually over years by overall radiology training and clinical experience in general rather than by experience with low-dose appendiceal CT specifically.

Evaluating the Patient with Right Lower Quadrant Pain

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

Predictive Factors to Distinguish Between Patients With Noncomplicated Appendicitis and Those With Complicated Appendicitis

Purpose

Recently, randomized controlled trials have reported that conservative therapy can be a treatment option in patients with noncomplicated appendicitis. However, preoperative diagnosis of noncomplicated appendicitis is difficult. In this study, we determined predictive factors to distinguish patients with noncomplicated appendicitis from those with complicated appendicitis.

Methods

A total of 351 patients who underwent surgical treatment for acute appendicitis from January 2011 to December 2012 were included in this study. We classified patients into noncomplicated or complicated appendicitis groups based on the findings of abdominal computed tomography and pathology. We performed a retrospective analysis to find factors that could be used to discriminate between noncomplicated and complicated appendicitis.

Results

The mean age of the patients in the complicated appendicitis group (54.5 years) was higher than that of the patients in the noncomplicated appendicitis group (40.2 years) (P < 0.001), but the male-to-female ratios were similar. In the univariate analysis, the appendicocecal junction's diameter, appendiceal maximal diameter, appendiceal wall enhancement, periappendiceal fat infiltration, ascites, abscesses, neutrophil proportion, C-reactive protein (CRP), aspartate aminotransferase, and total bilirubin were statistically significant factors. However, in the multivariate analysis, the appendiceal maximal diameter (P = 0.018; odds ratio [OR], 1.129), periappendiceal fat infiltration (P = 0.025; OR, 5.778), ascites (P = 0.038; OR, 2.902), and CRP (P < 0.001; OR, 1.368) were statistically significant.

Conclusion

Several factors can be used to distinguish between noncomplicated and complicated appendicitis. Using these factors, we could more accurately distinguish patients with noncomplicated appendicitis from those with complicated appendicitis.

The comparison of the effectiveness of tomography and Alvarado scoring system in patients who underwent surgery with the diagnosis of appendicitis

OBJECTIVE

The aim of this study is to compare the effectiveness of computed tomography and Alvarado scoring system in the diagnosis of acute appendicitis in patients who underwent appendectomy with the preliminary diagnosis of acute appendicitis.

MATERIAL AND METHODS

One hundred and one patients who underwent appendectomy with the diagnosis of acute appendicitis between January and December 2011 were included in the study. Alvarado scores were calculated, and abdominal tomography scans were obtained for each patient before surgery. Patients with Alvarado score ≥7 were considered to have appendicitis while patients with a score <7 were considered not to have appendicitis. Patients were classified into two groups based on the presence of appendicitis findings on abdominal tomography. Histopathological examination of the appendices was performed following appendectomy. All patients were classified into groups according to pathology results, Alvarado score and tomography findings. The effectiveness of Alvarado score and tomography were compared using the McNemar test.

RESULTS

Sixty patients (59.4%) were male and 41 (40.6%) were female, with a mean age of 32 years (5-85 years). The rate of negative appendectomy was 3.9%. In 78 patients (77.3%) the Alvarado score was ≥7, while 23 patients (22.7%) had Alvarado scores <7. The presence of appendicitis was determined by histopathology in 22 out of 23 patients whose Alvarado score was <7. Tomography indicated appendicitis in 97 patients (95.9%) whereas four patients (4.1%) exhibited no signs of appendicitis by tomography. However, histopathological evaluation indicated the presence of appendicitis in those four patients as well.

CONCLUSION

The study results imply that tomography is a more effective means of diagnosing acute appendicitis as compared to the Alvarado scoring system.

Comparison of multislice computed tomography and clinical scores for diagnosing acute appendicitis

Objective

To compare Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) and Alvarado scores with multislice computed tomography (MSCT) for diagnosing acute appendicitis (AA).

Methods

This retrospective study included patients with abdominal pain who had undergone MSCT, and whose medical notes included RIPASA and Alvarado score parameters. MSCT was compared with RIPASA and Alvarado scores for diagnosing AA.

Results

Of 297 patients included, sensitivity, specificity and accuracy for diagnosing AA were 95.2%, 73.6% and 87.2% for RIPASA score (cutoff value 7.5) and 63.1%, 80.9% and 69.7% for Alvarado score (cutoff value 7). Sensitivity, specificity and accuracy of MSCT for diagnosing AA were 98.9%, 96.4% and 98.0%, respectively. In terms of accuracy, statistically significant differences were observed between RIPASA and Alvarado scores, and between MSCT and RIPASA scores. The mean RIPASA score was significantly different in the simple AA group (9.7 ± 2.2) compared with other AA groups (10.5 ± 1.7). No statistically significant difference was observed in RIPASA score between nonperforated and perforated AA. MSCT sensitivity, specificity and accuracy for diagnosing simple AA were 94.1%, 96.4% and 95.8%, respectively; for differentiating perforated and nonperforated AA, scores were 90.2%, 95.2% and 94.1%, respectively.

Conclusion

MSCT is the optimum diagnostic tool for AA, followed by RIPASA score and Alvarado score, particularly in diagnosing simple and perforated AA.

Important CT findings for prediction of severe appendicitis: involvement of retroperitoneal space

Background

Determination of the severity of appendicitis and differentiation between complicated and uncomplicated appendicitis are clinically important. Severe appendicitis frequently affects extraperitoneal spaces. We have investigated CT findings of retroperitoneal space (RPS) in patients with appendicitis to create a model for identification of complicated appendicitis.

Method

CT images of 223 patients with pathologically proven appendicitis were reviewed. The total number of the segments in RPS where inflammatory changes were located (RPS count) was obtained as well as appendiceal diameter, appendicolithiasis, WBC count, and CRP level. Data were analyzed to identify factors indicating complicated appendicitis. Univariate analysis was conducted to identify statistically significant variables. A multivariable logistic regression analysis was performed in order to find independent predictors of complicated appendicitis.

Results

Patients with complicated appendicitis were more likely to have higher RPS count (P < 0.001), appendicolithiasis (P = 0.002), higher CRP level (P < 0.001), and greater appendix diameter (P < 0.001) than patients with uncomplicated appendicitis. Statistical analysis showed RPS count was the most helpful predictor of complicated appendicitis.

Conclusion

Radiologists and surgeons should be aware of the importance of CT findings in RPS when treating patients with appendicitis. Complicated appendicitis can be predicted by RPS count, diameter of the appendix, appendicolithiasis, and CRP level.

How to evaluate appendices with borderline diameters on CT: proposal of a quick solution to overcome the limitations of the established CT criteria

RATIONALE AND OBJECTIVES

To propose a useful computed tomography (CT) criterion, the diameter with compression (DWC), especially in appendices with borderline diameters.

MATERIALS AND METHODS

We retrospectively collected 216 patients with visible appendices on CT after clinicopathologic confirmation of appendicitis. Each CT criterion of appendicitis was evaluated by an experienced abdominal radiologist: maximal outer diameter (MOD), DWC, mural thickness and enhancement, periappendiceal infiltration, and appendicolith. DWC is the expected diameter after deduction of the intraluminal compressible contents such as air and feces. All the CT criteria were compared in the appendicitis and nonappendicitis group.

RESULTS

The areas under the receiver operating characteristic curve (AUC) of the MOD and the DWC were 0.967 and 0.973, respectively. The optimal cutoff value was 8.2 mm for the MOD and 6.6 mm for the DWC. Twenty-five of the 80 appendicitis patients (31.2%) and 62 of the 136 nonappendicitis patients (45.6%) had MODs between 5.7 mm and 9.8 mm in the overlap between the two groups. In this overlap, the AUC of the MODs declined sharply to 0.767, whereas the AUC of the DWCs remained 0.923. Use of the criterion of DWC >6.6 mm yielded a sensitivity of 84.0%, a specificity of 88.7%, and an accuracy of 87.4%. There were no other criteria with both sensitivity and specificity >80% in the range of overlap.

CONCLUSIONS

The proposed CT criterion of the DWC is not affected by normal distension or periappendiceal inflammation but only by true appendicitis. Therefore, DWC can improve the diagnostic performance of appendicitis regardless of the MOD.

Xanthogranulomatous appendicitis causing an endometrial abscess: radiological findings

Xanthogranulomatous inflammation (XGI) is a rare chronic inflammatory condition most commonly involving the kidneys and gallbladder. The condition is histopathologically characterized by the presence of foamy histiocytes, lymphocytes, and plasma cells. A few reports describing appendicitis caused by XGI have appeared in the English-language literature. However, no study has yet focused on the imaging features of xanthogranulomatous appendicitis (XGA). We present a pathologically confirmed case of XGA with an endometrial abscess; the patient underwent ultrasonography, computed tomography, and magnetic resonance imaging. To the best of our knowledge, this is the first case of XGA with uterine and right adnexal involvement presenting as a complicated pelvic abscess on radiological imaging.

Acute appendicitis in children: ultrasound and CT findings in negative appendectomy cases

BACKGROUND

To decrease the negative appendectomy rate in children, knowledge of the misleading imaging findings on US and CT in negative appendicitis cases is important.

OBJECTIVE

To evaluate the negative appendectomy rate and describe the imaging findings of US and CT that lead radiologists to misdiagnose acute appendicitis in children.

MATERIALS AND METHODS

From 2007 to 2013, 374 children operated for suspected appendicitis were proved to either have acute appendicitis (n = 348) or to be negative for appendicitis (n = 26) on pathological reports. Negative appendectomy rates were compared among imaging modalities, age groups and genders. We retrospectively reviewed US and CT findings from negative appendectomy cases.

RESULTS

The overall negative appendectomy rate was 7.0% (26/374). There were no statistically significant differences among the subgroups. The most common misleading presentations on US were sonographic tenderness (9/16, 56%) and non-compressibility (9/16, 56%). The most common misleading finding on CT were the presence of an appendicolith or hyperdense feces (5/12, 42%). Periappendiceal fat inflammation was observed in only one case of negative appendicitis on US and on CT.

CONCLUSION

Radiologists can misdiagnose children with equivocal diameters of appendices as having acute appendicitis when sonographic tenderness or non-compressibility is present on US and when an appendicolith or hyperdense feces is noted on CT. The possibility of negative appendicitis should be borne in mind when periappendiceal fat inflammation is absent or minimal in indeterminate cases.

Inflammatory appendix mass in patients with acute appendicitis: CT diagnosis and clinical relevance

The purpose of our study was to analyze the clinical relevance of computerized tomography (CT) in providing the diagnosis of inflammatory appendix mass (IAM) in patients with acute appendicitis. The CT images of 134 patients were reviewed. Two groups of patients were made according to the presence (group 1; n = 21) or the absence (group 2; n = 113) of IAM. Clinical signs of patients, CT features, complications at surgery, and histological examinations were noted. Inter-observer agreement was assessed by using kappa statistics. Twenty-one patients presenting with CT features of IAM were diagnosed. An excellent inter-observer agreement (κ = 0.94) was assessed for the diagnosis of IAM. No significant statistical difference in the age distribution was observed between patients with IAM (mean age 55) and patients without (mean age 45) (p = 0.2232). No clinical sign showed a statistically significant association with the presence of IAM (p = 0.707) or with complication encountered at surgery (p = 0.180). Delay to CT examination was 5.4 days in patients presenting with CT features of IAM and of 1.7 days for patients presenting without (p = 0.0001). Conversely to acute appendicitis complicated by simple perforation (p = 0.153) or peri-appendicular abscess (p = 0.501), acute appendicitis presenting with IAM showed a statistically significant association with complications encountered at surgery (p = 0.0003) and the need for conversion to open surgery (p = 0.001). Performing CT in complicated acute appendicitis provides the diagnosis of IAM. Distinction of IAM appeared to be of clinical relevance, since immediate surgery in IAM was statistically associated with surgical complications and conversion to open surgery in our study.

Intraluminal appendiceal fluid is a predictive factor for recurrent appendicitis after initial successful non-operative management of uncomplicated appendicitis in pediatric patients

BACKGROUND

The risk factors for recurrent appendicitis in pediatric patients are unclear. This study aimed to identify the predictive factors for recurrent appendicitis in pediatric patients who initially underwent successful non-operative management of uncomplicated appendicitis.

METHODS

Potential predictive factors for recurrent appendicitis in terms of clinical characteristics, laboratory data, and abdominal ultrasonography and computed tomography findings, were evaluated.

RESULTS

This study included 125 patients who underwent initial successful non-operative management of appendicitis. The rate of recurrent appendicitis was 19.2%, and the mean time to recurrence was 12.6 months. Univariate analyses found that rebound tenderness, muscle guarding, appendicoliths, appendiceal diameter >9 mm, and intraluminal appendiceal fluid were associated with recurrent appendicitis. Multivariate analysis identified only intraluminal appendiceal fluid as an independent predictor of recurrent appendicitis.

CONCLUSIONS

Intraluminal appendiceal fluid is a predictive factor for recurrent appendicitis after initial non-operative management. The results of this study provide valuable information that may help to determine the appropriate management during the first episode of appendicitis.

The normal appendix on CT: does size matter?

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Computed tomography with intravenous contrast alone: the role of intra-abdominal fat on the ability to visualize the normal appendix in children

BACKGROUND

Computed tomography (CT) with enteric contrast is frequently used to evaluate children with suspected appendicitis. The use of CT with intravenous (IV) contrast alone (CT IV) may be sufficient, however, particularly in patients with adequate intra-abdominal fat (IAF).

OBJECTIVES

The authors aimed 1) to determine the ability of radiologists to visualize the normal (nondiseased) appendix with CT IV in children and to assess whether IAF adequacy affects this ability and 2) to assess the association between IAF adequacy and patient characteristics.

METHODS

This was a retrospective 16-center study using a preexisting database of abdominal CT scans. Children 3 to 18 years who had CT IV scan and measured weights and for whom appendectomy history was known from medical record review were included. The sample was chosen based on age to yield a sample with and without adequate IAF. Radiologists at each center reread their site's CT IV scans to assess appendix visualization and IAF adequacy. IAF was categorized as "adequate" if there was any amount of fat completely surrounding the cecum and "inadequate" if otherwise.

RESULTS

A total of 280 patients were included, with mean age of 10.6 years (range = 3.1 to 17.9 years). All 280 had no history of prior appendectomy; therefore, each patient had a presumed normal appendix. A total of 102 patients (36.4%) had adequate IAF. The proportion of normal appendices visualized with CT IV was 72.9% (95% confidence interval [CI] = 67.2% to 78.0%); the proportions were 89% (95% CI = 81.5% to 94.5%) and 63% (95% CI = 56.0% to 70.6%) in those with and without adequate IAF (95% CI for difference of proportions = 16% to 36%). Greater weight and older age were strongly associated with IAF adequacy (p < 0.001), with weight appearing to be a stronger predictor, particularly in females. Although statistically associated, there was noted overlap in the weights and ages of those with and without adequate IAF.

CONCLUSIONS

Protocols using CT with IV contrast alone to visualize the appendix can reasonably include weight, age, or both as considerations for determining when this approach is appropriate. However, although IAF will more frequently be adequate in older, heavier patients, highly accurate prediction of IAF adequacy appears challenging solely based on age and weight.

Pitfalls and mimickers at 64-section helical CT that cause negative appendectomy: an analysis from 1057 appendectomies

PURPOSE

To determine the rate of negative appendectomy and clarify the causes of negative appendectomy in patients with clinically suspected acute appendicitis who had surgery after 64-section helical computed tomography (CT).

MATERIAL AND METHODS

A retrospective analysis of 1057 patients who had appendectomy after 64-section helical CT was performed to determine the rate of negative appendectomy. The 64-section helical CT examinations obtained with submillimeter and isotropic voxels in the patients with negative appendectomy were analyzed by two readers and compared to clinical, operative and histopathological reports, discharge summaries and original radiology reports.

RESULTS

The negative appendectomy rate was 1.7% (18/1057). Appendix enlargement (>6 mm) and fat stranding were present in 17 (17/18; 94%) and 6 patients (6/18; 33%), respectively. In 13 patients (13/18; 72%) 64-section helical CT findings were consistent with acute appendicitis. Interpretive errors in original imaging reports were identified in five patients (5/18; 28%).

CONCLUSION

The preoperative use of 64-section helical CT results in a very low rate of negative appendectomy. Patients with negative appendectomy have 64-section helical CT findings consistent with a diagnosis of acute appendicitis in the majority of cases. Interpretive errors are less frequent.

Computed tomography mimics of acute appendicitis: predictors of appendiceal disease confirmed at pathology

Purpose:

Imaging and pathology findings are used to analyze the capability of computed tomography (CT) to distinguish between acute appendicitis and radiological mimickers.

Materials and Methods:

A retrospective review of 5861 patients undergoing abdominopelvic CT from 2000 to 2008 for suspicion of acute appendicitis was performed. Appendix diameter, surrounding inflammation, appendicolith, and location were assessed. Only those cases were included where patients underwent surgery for acute appendicitis on CT findings. Pathology specimens were examined and those indicative of acute appendicitis were identified. Statistical analysis was performed to correlate pathology and CT signs.

Results:

A total of 969 of the 5681 patients were included in the study. Acute appendicitis was verified in 870/969 (89%) cases, while 99/969 (11%) demonstrated either chronic findings (i.e., fibrosis [32%], granulomatous disease [16%], lymphoid hyperplasia [11%]) or no abnormality. In regression models, appendiceal diameter >7 mm (odds ratio [OR] = 3.98, P < 0.0001) and mesenteric fat stranding (OR = 6.04, P < 0.0001) were associated with acute appendicitis. Nearly 87% (754/870) of acute appendicitis cases showed both signs on CT, compared with 53% (52/99) of those with other pathologic finding (P < 0.0001). In cases with non-appendicitis findings, 39% (39/99) had only one of these signs compared with 13% (112/870) of those with acute appendicitis (P < 0.0001).

Conclusion:

Diseases of the appendix other than acute appendicitis may manifest with isolated radiological findings and should be considered as part of the differential diagnosis in cases of borderline acute appendicitis.

[Intrathoracic acute appendicitis. A case report]

Intrathoracic appendicitis is an uncommon diagnosis. We report the case of a 6-year-old boy with elevated CRP and no fever, who complained of nonspecific abdominal pain. A diaphragmatic hernia was suspected on a chest X-ray and confirmed by an ultrasound examination. A multidetector CT scan revealed intrathoracic acute appendicitis associated with a right posterolateral Bochdalek hernia. Abdominal diseases associated with late-presenting congenital diaphragmatic hernia are often manifested by an atypical clinical presentation, which can be a source of delay or error in diagnosis. We recommend radiological exploration in the case of diaphragmatic hernia, even with subtle clinical findings in the search of associated gastrointestinal complications.

Epiploic appendagitis in a 27-year-old man

BACKGROUND

Epiploic appendagitis is an ischemic infarction of an epiploic appendage caused by torsion or spontaneous thrombosis of the central draining vein. Epiploic appendagitis is self-limited without surgery, and it is imperative for clinicians to be familiar with this entity.

CASE REPORT

A healthy 27-year-old man was admitted due to acute right lower quadrant abdominal pain. Physical examination showed focal abdominal tenderness with slight rebound tenderness. Laboratory tests showed leukocytosis and an increased serum C-reactive protein level. Computed tomography (CT) showed a fatty ovoid pericolonic mass measuring 12 mm in diameter, with a circumferential hyperdense ring that abutted on the ascending colon and was surrounded by ill-defined fat stranding with a hyperdense ring. These findings were diagnostic of primary epiploic appendagitis. The patient was given high-dose antibiotics due to the secondary inflammation involving the parietal peritoneum.

CONCLUSIONS

Epiploic appendagitis presents with an abrupt onset of focal abdominal pain and tenderness without significant guarding or rigidity; it is an uncommon and difficult diagnosis. With awareness of this condition, however, evaluation by CT can provide an accurate diagnosis of epiploic appendagitis, distinguishing it from conditions with clinically overlapping manifestations.