Mucocoele of the appendix.

Introduction: Mucocoele of the appendix occurs in 0.2-0.7% of people in the world without any well-defined clinical symptoms. It occurs when there is an accumulation of mucous in the lumen of the appendix. Case Presentation: We present three cases: a 48-year-old male admitted to the emergency room with a one-day history of right iliac fossa pain. Abdominal examination was suggestive of acute appendicitis. The initial abdominal computerised tomography scan was reported as being unremarkable. At surgery, a firm tumour of the appendix was found, and a limited right hemicolectomy was done. Histopathology confirmed a mucocoele of the appendix with borderline mucinous histology.The second case is a 63-year-old man who presented with a one-year history of abdominal distension and weight loss. Previous abdominal ultrasound was suggestive of liver cirrhosis with significant ascitic fluid. Abdominal magnetic resonance imaging found an appendix mucocoele with infiltration of the omentum and scalloping of the liver surface suggestive of pseudomyxoma peritonei. A percutaneous biopsy of the omental mass confirmed metastatic mucinous adenocarcinoma of the appendix.The third case is a 68-year-old man who, during an annual medical check-up, had an incidental finding of a cystic right iliac fossa mass on ultrasound, confirmed on abdominopelvic computerised tomography scan to be an appendix mucocele. He had laparoscopic appendicectomy. The histopathological diagnosis confirmed a mucinous cystadenoma of the appendix. Conclusion: Preoperative diagnosis of appendiceal mucocoele is difficult and commonly discovered intraoperatively. The prognosis is good for the histologically benign type, but it is poor when malignant or peritoneal lesions are present. Funding: None declared.

Assessment of Alvarado criteria, ultrasound, CRP, and their combination in patients with suspected acute appendicitis: a single centre study.

BACKGROUND: Acute appendicitis (AA) is one of the most common reasons for visiting the emergency room. The lack of proper diagnosis and rapid treatment of AA may lead to severe complications such as intestinal perforation and increased mortality. This study aimed to evaluate the diagnostic accuracy of the Alvarado criteria, ultrasound, and CRP criteria in comparison with their combined use in patients with suspected AA who presented to the emergency room. METHODS: In this diagnostic accuracy study, 1411 patients with suspected AA who presented to the emergency department of Firoozabadi Hospital affiliated with Iran University of Medical Sciences and underwent appendectomy from October 2019 to October 2021 were examined. Nine hundred eighty-eight patients were enrolled. All patients were assessed using Alvarado, CRP, and ultrasound. The definitive diagnosis of AA was based on pathological findings and was considered the gold standard. Statistical analyses were performed with STATA VER 11.5. The diagnostic accuracy for each group was compared using the Pearson chi-square test. A value of p < 0.05 was considered statistically significant. RESULTS: The mean age was 29.57 ± 13.66 years. The sensitivity and specificity of Alvarado in the diagnostic accuracy of appendicectomy were 75.2% and 61.3% (CI = 95%), respectively. The sensitivity of ultrasound and CRP for predicting appendicitis was significantly higher than the Alvarado criteria. The diagnostic accuracy for CRP was significantly higher than ultrasound (64.9% vs. 60.7%, P: 0.003). The diagnostic accuracy of the simultaneous use of Alvarado + CRP and CRP + Ultrasound was significantly higher than that of Alvarado + ultrasound. The sensitivity, specificity, and diagnostic accuracy of the simultaneous use of all three criteria together (Alvarado + Ultrasound + CRP) were estimated to be 94.9%, 25.8%, and 81.5% (CI = 95%), respectively, which were significantly higher than the use of other criteria. CONCLUSION: This study showed that the Alvarado criteria had inadequate diagnostic sensitivity and accuracy for diagnosing acute appendicitis. The diagnostic accuracy of acute appendicitis increases to over 90% using the three Alvarado, ultrasound, and CRP criteria at the same time.

Introducing the ratio of cross diameters of the appendix for ultrasound diagnosis of acute appendicitis can significantly increase specificity.

PURPOSE: To validate whether the introduction of the ratio of the cross diameters on the transverse section of the appendix (RATIO) ≤ 1.18 is useful for improving the ultrasound diagnosis of acute appendicitis (AA). METHODS: Data from 220 patients with AA and 110 patients with a normal appendix were retrospectively studied. The RATIO ≤ 1.18, maximal outer diameter (MOD) > 6 mm, and a combination of RATIO ≤ 1.18 and MOD > 6 mm were used for predicting AA. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, positive and negative predictive values (PPV and NPV) were calculated. RESULTS: The RATIO ≤ 1.18, MOD > 6 mm, and a combination of RATIO ≤ 1.18 and MOD > 6 mm for predicting AA showed a sensitivity of 90, 100, and 90%; specificity of 79.1, 27.3, and 88.2%; and AUC of 0.845, 0.636, and 0.891, respectively. When comparing the outcomes between MOD > 6 mm and a combination of MOD > 6 mm and RATIO ≤ 1.18, the specificity and PPV increased from 27.3 to 88.2% and 73.3 to 93.8%, respectively (all P < 0.0001). The sensitivity and NPV decreased from 100 to 90% and 100 to 81.5%, respectively (all P < 0.0001). The AUC increased from 0.636 to 0.891 (P < 0.0001). When comparing the AUC of MOD > 6 mm, and a combination of RATIO ≤ 1.18 and MOD > 6 mm for predicting AA with the AUC in a previous study, there were no significant differences between each other (all P > 0.05). CONCLUSION: Introducing the RATIO ≤ 1.18 for the evaluation of AA can improve the diagnostic performance and significantly increase specificity.

Partial visualization of appendix on ultrasound: What does it mean in the child with suspected appendicitis?

BACKGROUND: Visualization of the entire appendix, including the tip, is thought, but has not been demonstrated, to be important for exclusion of appendicitis by ultrasound. OBJECTIVE: To determine if incomplete visualization of the appendix has negative clinical ramifications including missed appendicitis. METHODS: Under IRB approval we retrospectively reviewed right lower quadrant ultrasound reports from January 2017 to December 2020 to identify examinations with impressions of full visualization of the normal appendix, non-visualization of the appendix with and without secondary findings of appendicitis, and partial visualization of the appendix. Electronic health records were reviewed for follow-up imaging within 48 h, and surgery with pathology reports (if available). RESULTS: 12,193 examinations were included. 4171 (34.2 %) had full visualization of a normal appendix, 5369 (44.0 %) had non-visualization with no secondary findings, and 234 (1.9 %) had non-visualization with secondary findings, The frequencies of appendicitis in these three groups were 34 (0.8 %), 283 (5.3 %), and 127 (54.3 %) respectively. The appendix was partially visualized in 338 (2.8 %) patients with secondary findings present in 53 (15.6 %). Partial visualization without secondary findings had a similar frequency (4.9 %, 14/285) of appendicitis to non-visualized appendix without secondary findings (p = 0.797) and a higher frequency than full visualization of a normal appendix (p < 0.0001). Partial visualization with secondary findings had similar rates (54.7 %, 29/53) to non-visualized appendix with secondary findings (p = 0.953). CONCLUSION: Partial visualization of the appendix with ultrasound (with and without secondary findings) is associated with similar frequencies of appendicitis as non-visualization of appendix (with and without secondary findings).

Predictive values of indirect ultrasound signs for low risk of acute appendicitis in paediatric patients without visualisation of the appendix on ultrasound.

BACKGROUND AND OBJECTIVES: The ability to rule appendicitis in or out using ultrasound is limited by studies where the appendix is not visualised. We determined whether the absence of indirect ultrasound signs can rule out appendicitis in children undergoing a radiology-performed ultrasound in which the appendix is not visualised METHODS: This was a single-centre retrospective observational study of patients aged 3-13 with a clinical suspicion of acute appendicitis evaluated in a Paediatric Emergency Department in Spain from 1 January 2013 to 31 December 2019. For those patients who had formal ultrasound, direct and indirect findings of ultrasound were abstracted from the ultrasound report. The surgical pathology report was established as the gold standard in patients who underwent an appendectomy. In those who did not, appendicitis was considered not to be present if there was no evidence in their charts that they had undergone an appendectomy or conservative therapy for appendicitis during the episode. The main outcome variable was the diagnosis of acute appendicitis. For patients undergoing ultrasound, the independent association of each indirect ultrasound sign with the diagnosis of appendicitis in patients without a visualised appendix was analysed using logistic regression. RESULTS: We included 1756 encounters from 1609 different episodes. Median age at the first visit of each episode was 10.1 years (IQR, 7.7-11.9) and 921 (57.2%) patients were men. There were 730 (41.6%) encounters with an Alvarado score ≤3, 695 (39.6%) with a score 4-6 and 331 (18.9%) with a score ≥7. Appendicitis was diagnosed in 293 (17.8%) episodes. Ultrasonography was performed in 1115 (61.6%) encounters, with a visualised appendix in 592 (53.1%).The ultrasound findings independently associated with appendicitis in patients without a visualised appendix were the presence of free intra-abdominal fluid in a small quantity (OR:5.0 (95% CI 1.7 to 14.6)) or in an abundant quantity (OR:30.9 (95% CI 3.8 to 252.7)) and inflammation of the peri-appendiceal fat (OR:7.2 (95% CI 1.4 to 38.0)). The absence of free fluid and inflammation of the peri-appendiceal fat ruled out acute appendicitis in patients with an Alvarado score <7 with a sensitivity of 84.6% (95% CI 57.8 to 95.7) and a negative predictive value of 99.4% (95% CI 97.8 to 99.8). CONCLUSIONS: Patients with an Alvarado score <7 and without a visualised appendix on ultrasound but who lack free fluid and inflammation of the peri-appendiceal fat are at very low risk of acute appendicitis.

Predictive factors for recurrent acute appendicitis after conservative treatment.

INTRODUCTION: Conservative treatment of acute appendicitis is gaining popularity, and identifying patients with a higher risk of recurrence is becoming increasingly important. Previous studies have suggested that older age, male sex, diabetes, appendicolith and abscess formation may be contributing factors, however, results from the adult population are inconsistent. AIM: This study aims to identify predictive factors for recurrent appendicitis after conservative treatment. METHODS: This retrospective study included patients with conservatively treated acute appendicitis at Skåne University Hospital, Sweden during 2012-2019. Information on patient demographics at index admission and follow-up data were retrieved from medical charts and radiologic images. Uni -and multivariable logistic regression analysis were performed using Stata Statistical Software. RESULTS: In total, 379 patients with conservatively treated acute appendicitis were identified, of which 78 (20.6%) had recurrence. All patients were followed-up for a minimum of 41 months after the first diagnosis of acute appendicitis unless appendectomy after successful conservative treatment or death occurred during follow-up. The median time to recurrence was 6.5 (1-17.8) months. After multivariable logistic regression analysis, external appendix diameter >10 mm [OR 2.4 (CI 1.37-4.21), p = .002] and intra-abdominal abscess [OR 2.05 (CI 1.18-3.56), p = .011] on computed tomography were significant independent risk factors for recurrent appendicitis. Appendicolith was not associated with an increased risk of recurrence. CONCLUSION: This study suggests abscess formation and appendix distension of >10 mm to be potential risk factors for recurrent acute appendicitis after initial successful conservative treatment.

Reducing Postoperative CT Imaging for Children With Complicated Appendicitis: A Pediatric Surgical Quality Collaborative Quality Improvement Project.

BACKGROUND: Despite widespread initiatives to reduce ionizing radiation for appendicitis diagnosis, computed tomography (CT) scanning postoperatively remains common. The Pediatric Surgery Quality Collaborative (PSQC) aimed to identify differences between children's hospitals with high and low postoperative CT usage for complicated appendicitis. METHODS: Using National Surgery Quality Improvement Program Pediatric data from PSQC children's hospitals, we compared postoperative CT imaging for complicated appendicitis (April 2020-March 2021). Key stakeholders from 11 hospitals (5 low CT utilization, 6 high CT utilization) participated in semi-structured interviews regarding postoperative imaging. Qualitative analysis of transcripts was performed deductively and inductively based on the Theoretical Domains Framework (TDF). RESULTS: Five of twelve TDF domains were most prominent in influencing CT use: skills, beliefs about capabilities, intentions/goals, memory and decision processes, and environment. Children's hospitals with lower rates of postoperative CT use tended to: trust and educate the ultrasound technicians; believe US strengths outweigh weaknesses; image no sooner than 7 days postoperatively; have access to sufficient quality improvement resources; maintain trusting relationships between specialties; and prioritize radiation stewardship. CONCLUSION: Hospitals at extremes of postoperative CT use for complicated appendicitis reveal strategies for improvement, which include imaging protocol development and adherence, quality improvement resource availability, interdisciplinary collaboration, and promoting radiation stewardship. LEVEL OF EVIDENCE: Level V.

Diagnosis of Pediatric Appendicovesical Fistula by Contrast-enhanced Ultrasound: A Case Report.

Appendicovesical fistula is a rare complication associated with appendicitis, Crohn's disease, or appendiceal tumors, posing significant diagnostic challenges. We reported a pediatric case of appendicovesical fistula that remained undiagnosed by non-contrast computed tomography, fluoroscopic voiding cystourethrography (VCUG). Although identified during cystoscopy, its connection to the fistula site could not be determined. However, the transvesical contrast-enhanced ultrasound clearly demonstrated the presence of fistula. Subsequently, laparoscopic appendectomy and bladder repair were performed successfully, leading to complete recovery in the patient. To our knowledge, this is the first reported diagnosis of appendicovesical fistula in children using contrast-enhanced ultrasound.

Ultrasound Assessment in Children With Suspected Appendicitis: Time to Revise Diagnostic Criteria: A Prospective Cohort Study.

Background: Although ultrasound is considered the gold standard for the evaluation of children with suspected appendicitis, there is still much debate about the most accurate ultrasound findings. The purpose of this study was to define the best ultrasound signs that could ultimately improve the diagnostic accuracy of ultrasound for diagnosing pediatric acute appendicitis, and to differentiate between simple appendicitis and complicated appendicitis. Patients and Methods: After approval by our Institutional Review Board, a prospective study was carried out from January 1, 2022, to July 31, 2023, in a pediatric emergency department. We included all patients aged under 14 years with suspected appendicitis and ultrasound-visualized appendix. Results: A total of 550 patients presented with suspected appendicitis during the study period. Of these children, 411 had an ultrasound-visualized appendix. Our patients' mean age was 9.4 years. The best positive predictive value of ultrasound was found for appendiceal diameter ≥7.5 mm. The combination of an appendiceal diameter <6 mm and the lack of peri-appendiceal free fluid on ultrasound rules out the diagnosis of appendicitis. The best diagnostic accuracy of ultrasound, which was 92%, was achieved for appendix diameters ≥6.5 mm. The sonographic sign giving the best ultrasound accuracy for diagnosing complicated appendicitis was an appendix diameter ≥9 mm. Conclusions: In conclusion, our present study demonstrated that appendiceal diameter ≥6.5 mm is the gold standard for diagnosing appendicitis in pediatric patients. The combination of an appendiceal diameter <6 mm and the lack of peri-appendiceal free fluid on ultrasound would rule out appendicitis.

Primary Omental Torsion in Children in the Laparoscopy Era: What Have we Learned so far?

BACKGROUND/AIM: Primary omental torsion is uncommon, mimicking appendicitis and other acute abdominal pathologies. It often escapes diagnosis on imaging investigation or conventional open laparotomy. This study aimed to evaluate the effect of laparoscopy on the various parameters of this entity, including incidence, diagnosis, and treatment. MATERIALS AND METHODS: A systematic review was performed, including PubMed and Scopus databases, without a time limit, following the PRISMA principles. A total of 16 articles from January 2000 to December 2023, corresponding to 56 children with primary omental torsion, complied with the research criteria. RESULTS: Primary omental torsion was associated with obesity. Symptoms were right abdomen oriented, often compared to those of acute appendicitis. Preoperative ultrasound displayed low diagnostic accuracy, whereas computerized tomography diagnosed only two thirds of cases. In all patients, the vermiform appendix was normal. CONCLUSION: Laparoscopy affected both diagnosis and treatment of primary omental torsion in children. Easy peritoneal cavity access rendered possible the diagnosis of cases previously discharged as abdominal pain of unknown etiology. Combined with the increased pediatric obesity, it also affected primary omental torsion incidence. The recent pathogenetic theories may be better supported today, as laparoscopy provides a detailed view in situ, and facilitates harvesting of fat tissue from the omentum for molecular investigation. The diagnostic efficiency of laparoscopy is superior to ultrasonography and computerized tomography. Finally, the removal of the ischemic omentum is technically easier compared to the open laparotomy alternative with all the technical difficulties of traction of a vulnerable hemorrhagic tissue through a small incision.

Acute diverticulitis of the appendix.

Acute diverticulitis of the appendix (ADA), though uncommon, often presents similarly to acute appendicitis but carries a higher risk of complications such as perforation and malignancy. We report the case of a male patient in his 50s with acute right iliac fossa abdominal pain, diagnosed via CT scan with ADA. Urgent laparoscopic appendicectomy was performed, and the patient was discharged without further issues. This case highlights the importance of promptly identifying and managing such conditions to minimise complications and improve outcomes. Despite the overlap in symptoms between appendiceal diverticulitis and acute appendicitis, accurate diagnosis is crucial for appropriate treatment. Healthcare providers should maintain a high index of suspicion, particularly in older patients presenting with an acute appendicitis, like clinical picture to ensure timely intervention and optimal patient care.

Diagnostic pathways in acute appendicitis: Clinical score plus ultrasound outperform CT scan or upfront surgery, especially in doubtful cases.

BACKGROUND: Controversies remain on the diagnostic strategy in suspected AA, considering the different settings worldwide. MATERIAL AND METHODS: A prospective observational international multicentric study including patients operated for suspected AA with a definitive histopathological analysis was conducted. Three groups were analyzed: (1) No radiology; (2) Ultrasound, and (3) Computed tomography. The aim was to analyze the performance of three diagnostic schemes. RESULTS: Three thousand and one hundred twenty three patients were enrolled; 899 in the no radiology group, 1490 in the US group, and 734 in the CT group. The sex ratio was in favor of males (p < 0.001). The mean age was lower in the no radiology group (24 years) compared to 28 and 38 years in US and CT-scan groups, respectively (p < 0.001). Overall, the negative appendectomy rate 3.8%: no radiology group (5.1%) versus US (2.9%) and CT-scan (4.1%) (p < 0.001). The sensitivity and specificity analysis showed the best balance in clinical evaluation + score + US. These data reach the best results in those patients with an equivocal Alvarado score (4-6). Inverse probability weighting (IPW), showed as the use of ultrasound, is significantly associated with an increased probability of formulating the correct diagnosis (p 0.004). In the case of a CT scan, this association appears weaker (p 0.08). CONCLUSION: The association of clinical scores and ultrasound seems the best strategy to reach a correct preoperative diagnosis in patients with clinical suspicion of AA, even in those population subgroups where the clinical score may have an equivocal result. This strategy can be especially useful in low-resource settings worldwide. CT-scan association may improve the detection of patients who may potentially be submitted to conservative treatment.

Accuracy of point-of-care ultrasound in the diagnosis of acute appendicitis in a pediatric emergency department.

PURPOSE: To investigate the accuracy of point-of-care ultrasound (PoCUS) in diagnosing acute appendicitis in children; to evaluate the concordance between PoCUS performed by a pediatric emergency physician (PedEm) and ultrasonography (US) performed by a radiologist; to draw a "learning curve." METHODS: We prospectively enrolled children aged 0-14 years old led to the Emergency Department of Regina Margherita Children's Hospital, from January 2021 to June 2021, with suspected acute appendicitis. PoCUS was performed by a single trained PedEm, blindly to the radiologist's scan. A "self-assessment score" and the "time of duration of PoCUS" were recorded for each patient. Final diagnosis of appendicitis was made by a pediatric surgeon. RESULTS: We enrolled 62 children (2-14 years). Overall sensitivity of PoCUS was 88%, specificity 90%; PPV 90.6%, and NPV 86.6%. Global concordance between the PedEm and the radiologist was good/excellent (k 0.74). The mean duration of PoCUS significantly decreased during the study period, while the self-assessment score increased. CONCLUSION: This is a preliminary study that shows the effectiveness of PoCUS in diagnosing acute appendicitis; furthermore, it shows how the PedEm's performance may improve over time. The learning curve showed how the experience of the PedEm affects the accuracy of PoCUS.

A CT-based radiomics nomogram involving the cystic fluid area for differentiating appendiceal mucinous neoplasms from appendicitis with intraluminal fluid.

OBJECTIVE: To develop and validate a radiomics nomogram based on computed tomography (CT) to distinguish appendiceal mucinous neoplasms (AMNs) from appendicitis with intraluminal fluid (AWIF). METHOD: A total of 211 patients from two medical institutions were retrospectively analysed, of which 109 were pathologically confirmed as having appendicitis with concomitant CT signs of intraluminal fluid and 102 as having AMN. All patients were randomly assigned to a training (147 patients) or validation cohort (64 patients) at a 7:3 ratio. Radiomics features of the cystic fluid area of the appendiceal lesions were extracted from nonenhanced CT images using 3D Slicer software. Minimum redundancy maximum relevance and least absolute shrinkage and selection operator regression methods were employed to screen the radiomics features and develop a radiomics model. Combined radiomics nomogram and clinical-CT models were further developed based on the corresponding features selected after multivariate analysis. Lastly, receiver operating characteristic curves, and decision curve analysis (DCA) were used to assess the models' performances in the training and validation cohorts. RESULTS: A total of 851 radiomics features were acquired from the nonenhanced CT images. Subsequently, a radiomics model consisting of eight selected features was developed. The combined radiomics nomogram model comprised rad-score, age, and mural calcification, while the clinical-CT model contained age and mural calcification. The combined model achieved area under the curves (AUCs) of 0.945 (95% confidence interval [CI]: 0.895, 0.976) and 0.933 (95% CI: 0.841, 0.980) in the training and validation cohorts, respectively, which were larger than those obtained by the radiomics (training cohort: AUC, 0.915 [95% CI: 0.865, 0.964]; validation cohort: AUC, 0.912 [95% CI: 0.843, 0.981]) and clinical-CT models (training cohort: AUC, 0.884 [95% CI: 0.820, 0.931]; validation cohort: AUC, 0.767 [95% CI: 0.644, 0.863]). Finally, DCA showed that the clinical utility of the combined model was superior to that of the clinical CT and radiomics models. CONCLUSION: Our combined radiomics nomogram model constituting radiomics, clinical, and CT features exhibited good performance for differentiating AMN from AWIF, indicating its potential application in clinical decision-making.