Imaging of acute right lower quadrant abdominal pain: differential diagnoses beyond appendicitis

Appendiceal atresia causing recurrent right lower quadrant pain without inflammation

An 11-year-old girl presented with recurrent right lower quadrant (RLQ) pain. There was no evidence of inflammation and appendiceal swelling except at the initial onset. The repeated presence of a small amount of ascites at the time of abdominal pain triggered the performance of exploratory laparoscopy. Intraoperative examination revealed a non-inflamed, unswollen appendix with a cord-like atretic segment at the middle part and an appendectomy was performed. At 46 months follow-up, she remained asymptomatic. In patients with recurrent RLQ pain of unknown cause, it is necessary to consider diagnostic laparoscopy while keeping appendiceal atresia in mind as a differential diagnosis.

Incidence of acute diverticulitis compared to appendicitis in emergency wards: a 10-year nationwide register and cohort study from Finland

BACKGROUND

The two most common abdominal infections in emergency departments (ED) are acute appendicitis (AA) and sigmoid diverticulitis (AD). The frequency of ED visits for diverticulitis has increased strongly in many countries during recent decades. The aim of this study was to analyze the nationwide changes in AD rate requiring hospital admission compared to AA during a 10-year study period.

METHODS

Register data of AD and AA in the whole of Finland were obtained between the years 2009 and 2018. Changes in the incidence and surgical treatment of AD in the whole country were compared to those of AA. Patient demographics and treatment of AD were analyzed in greater detail from a smaller cohort (n = 614).

RESULTS

The incidence of AD increased from 262 to 413 cases (58%) per 100,000 inhabitants during 10 years and emergency surgery for AD decreased from 27 to 24 cases per 100,000 (11%). The incidence of AA remained stable and varied from 118 to 124 annual cases per 100,000 inhabitants. In a patient cohort of AD (n = 614), most of the patients (68%) had only one episode of diverticulitis during 10 years; 16% were operated urgently, with a mortality of 8%. Disease-specific mortality increased from 0% to 5.7% along with patient age when comparing the age groups <50 years and > 70 years, respectively.

CONCLUSIONS

Our study indicates that the incidence of acute diverticulitis is still increasing and is now 2-3 times higher than that of appendicitis in emergency departments.

Diagnostic Accuracy of Abdominal Ultrasonography in Pediatric Acute Appendicitis

OBJECTIVE

To evaluate the diagnostic accuracy of ultrasonography in pediatric acute appendicitis.

METHODS

In this cross-sectional study, 230 children aged 5-15 years with the diagnosis of acute appendicitis were studied. This study included the evaluation of demographic indices, ultrasound findings at diagnosis, and then comparing the results with the description of the patient's procedure and the pathology report of these patients. Patients who did not undergo ultrasound before surgery or their ultrasound did not include the evaluation of appendicitis or their pathologic report was not available were excluded.

RESULTS

Overall, we have included a total number of 230 children with clinical diagnosis of acute appendicitis among whom there were 121 (52.6%) girls and 109 (47.4%) boys with mean age of 11.44 ± 2.90 years. Preoperative ultrasound report showed that 51.3% were normal and 48.7% had acute appendicitis. 34.8% had normal appendix and 65.2% had a pathological diagnosis of acute appendicitis. The sensitivity and specificity of ultrasound in these children were 58% and 68%, respectively. Positive and negative predictive values ​​were 77% and 46%, respectively. The area under curve (AUC) was 0.853 (CI 95% 0.788-0.917) indicating a test with moderate accuracy.

CONCLUSION

According to the obtained results, abdominal ultrasonography is of acceptable diagnostic accuracy in pediatric patients with acute appendicitis. The use of auxiliary techniques in ultrasound would increase the sensitivity and specificity in the diagnosis of acute appendicitis in children.

Early ultrasound in acute appendicitis avoids CT in most patients but delays surgery and increases complicated appendicitis if nondiagnostic - A retrospective study

BACKGROUND

We determined whether increasing early imaging (in the emergency department) was associated with earlier surgery and a decrease in complicated appendicitis.

METHODS

Retrospective study; 3013 operations between 12/2006-12/2016.

RESULTS

Early imaging increased from 13.1% to 74.1%, mostly due to increasing use of ultrasound. Negative appendectomies decreased from 10.7% to 5.1% (p < 0.001). Ultrasound was diagnostic in 80.5%. The false positive rate of ultrasound was 4%. Median time to surgery following positive ultrasound was 7.4 h (IQR 5.8-9.4), shorter compared to no early imaging (13.3 h, IQR 7.2-20.0; p < 0.001). However, median time to surgery following inconclusive and negative ultrasound was 11.5 h (IQR 8.7-16.1) and 17.0 h (IQR 10.3-26.7) respectively. The incidence of complicated appendicitis was 40% and 37.7%, higher than 21.5% in patients with positive US (p < 0.001).

CONCLUSIONS

Early imaging resulted in earlier surgery but did not reduce the incidence of complicated appendicitis. Ultrasound averted the need for CT in the majority of patients. When ultrasound was negative or inconclusive, time to surgery was delayed and the rate of complicated appendicitis higher.

Clinical and laboratory findings in the diagnosis of right lower quadrant abdominal pain: outcome analysis of the APPAC trial

BACKGROUND

The current research on acute appendicitis aims to improve the diagnostics and to clarify to whom antibiotic treatment might be the treatment of choice.

METHODS

The present study is a retrospective analysis of a prospectively collected data in our randomized multicenter trial comparing surgery and antibiotic treatment for acute uncomplicated appendicitis (APPAC trial, NCTO1022567). We evaluated 1321 patients with a clinical suspicion of acute appendicitis, who underwent computed tomography (CT). Age, gender, body temperature, pain scores, the duration of symptoms, white blood cell count (WBC) and C-reactive protein (CRP) were recorded on admission.

RESULTS

CT confirmed the diagnosis of acute appendicitis in 73% (n=970) and in 27% (n=351) it revealed no or other diagnosis. Acute appendicitis patients had significantly higher WBC levels than patients without appendicitis (median 12.2 and 10.0, respectively, p<0.0001), whereas CRP levels did not differ between the two groups. Ideal cut-off points were assessed with receiver operating characteristic (ROC) curves, but neither these markers or neither their combination nor any clinical characteristic could accurately differentiate between patients with acute appendicitis and those without. The proportion of patients with normal WBC count and CRP was significantly (p=0.0007) lower in patients with acute appendicitis than in patients without appendicitis.

CONCLUSIONS

Both clinical findings and laboratory tests are unable to reliably distinguish between patients with acute appendicitis and those without. If both WBC count and CRP are normal, acute appendicitis is very unlikely. The current results emphasize the role of CT imaging in patients with suspected acute appendicitis.

Chronic inflammation masquerading as an appendiceal tumour with peritoneal metastasis: the challenge of diagnosis and the lessons learnt

Advanced radiological imaging has largely replaced exploratory operations and has become an essential diagnostic tool clinicians routinely rely on. However, physicians are faced with a lot of radiological findings without histological proof, and assuming a more serious diagnosis may lead to unnecessary investigations and emotional stress for patients. We report an unusual presentation of chronic appendicitis with a synchronous peritoneal nodule on CT in a 76-year-old woman who presented with poor appetite, weight loss and a mass in the right iliac fossa. The coincidental finding of the nodule in addition to the suspicious appearance of the appendix raised concerns for primary appendiceal cancer with peritoneal metastasis. The case illustrates the patient's management and reflects on the learnt lessons with regard to careful use of invasive radiology-guided biopsies and interval imaging, as these could sometimes delay the diagnosis and management of a readily treatable disease.

Diverticulitis of the appendix, a distinctive entity: preoperative diagnosis by computed tomography

Diverticular disease of the appendix is rare and is usually diagnosed during surgery. We report a case of a 50-year-old man who presented to the emergency department with right lower quadrant pain of 1-day duration. A preoperative diagnosis of appendiceal diverticulitis was made by computed tomography of the abdomen. The patient underwent emergency laparoscopic appendectomy, which confirmed the diagnosis.

Omental infarction and its mimics: imaging features of acute abdominal conditions presenting with fat stranding greater than the degree of bowel wall thickening

The segmental omental infarction is a rare self-limited disorder presenting with aspecific clinical symptoms that may mimic several acute abdominal conditions. Therefore, a correct noninvasive diagnosis is important because treatment approaches range from monitoring to surgery. As omental infarction results in an important fat stranding that is much greater than the degree of bowel wall thickening, it suggests a narrower differential diagnosis: appendicitis, diverticulitis, epiploic appendagitis, and mesenteric panniculitis. In this pictorial essay, we point out the importance of imaging in identifying this typical sign allowing alternate diagnoses such as segmental omental infarction that can be conservatively managed.

Stump appendicitis: surgical background, CT appearance, and imaging mimics

Stump appendicitis, also known as remnant appendicitis, is an uncommon entity with little radiologic literature. It is the result of unintentional incomplete appendectomy with subsequent inflammatory changes in the appendiceal remnant. A retrospective review of the radiology and pathology archives at our institution over an 8-year period yielded six surgically/pathologically confirmed cases. Imaging findings at presentation were evaluated, including appendiceal stump length, appendiceal stump diameter, presence or absence of surrounding stranding in the periappendiceal fat, and presence or absence of complication (perforation or abscess). The CT findings of the six cases had an average surgical specimen appendiceal stump length of 3.5 cm (range 2.0-5 cm) and an average appendiceal diameter of 12.3 mm (range 10-16 mm). All six cases demonstrated the presence of periappendiceal inflammatory fat stranding on the CT scan. Range of imaging presentation is reviewed with pictorial examples as well as examples of potential false-positive cases (mimics) including Crohn's disease, residual surgical drain tract, and epiploic appendagitis. Familiarity with stump appendicitis as well as its imaging mimics may lead to earlier diagnosis and treatment and prevent unnecessary complications.

The accuracy of pre-appendectomy computed tomography with histopathological correlation: a clinical audit, case discussion and evaluation of the literature

The increasing use of computed tomography (CT) in acute appendicitis makes recognising the radiological hallmarks of the condition and its mimics vital. The differential diagnosis includes both appendiceal and nonappendiceal pathologies. The correlation between pre-appendectomy CT and post-appendectomy histopathology was audited retrospectively. Cases of clinico-histopathological discrepancy underwent blind peer-review, and possible improvements were discussed in the context of the medical literature. A grade for discrepancy was given based on the RADPEER scoring system, and interesting or discrepant cases were examined more closely to identify targets for education. Of the 199 procedures, 4 appendectomies were negative (histologically normal), 182 were positive (primary appendicitis) and 13 were incidental (another primary process caused inflammation). The positive predictive value for pre-appendectomy CT was 91.5 %, and the negative appendectomy rate was 2 %. There were many secondary pathologies, including neoplasia, tuberculosis and endometriosis. Although no CT reports missed a diagnosis that should be made “almost all of the time” and in 96 % of cases, the second, blinded radiologist agreed with the initial assessment, in 3 cases, a missed diagnosis altered clinical management; 2 were “understandable” misses but 1 was not. In five cases, a discrepancy was “understandable” but clinically insignificant. Overall, in comparison to the medical literature, the degree of clinico-histopathological correlation was good. Although identifying areas for improvement was challenging, after a pictorial review of four cases and a discussion of the medical literature, we present our audit results and some valuable learning points for use in the CT assessment of suspected acute appendicitis.

BWH emergency radiology-surgical correlation: omental hematoma with active extravasation: a rare diagnosis

We describe the radiological and intraoperative correlation of a large omental hematoma with active intra-abdominal bleeding secondary to omental lacerations in a 75-year-old man following blunt trauma from a motor vehicle accident. The purpose of this article is to emphasize the importance of recognizing omental and mesenteric injuries in trauma patients, as these injuries are rare and can be overlooked on CT.

Acute abdominal pain in childhood and adolescence: assessing the impact of sonography on diagnosis and treatment

PURPOSE

To assess the impact of ultrasonography on defining the diagnostic and therapeutic pathways for pediatric patients admitted to the emergency department for acute abdominal pain.

METHODS

We performed a retrospective study of all patients aged <16 years with acute abdominal pain who underwent ultrasound examination at our Diagnostic Imaging Department from October 2010 to March 2012. We investigated for each patient the pathway following ultrasound examination and definitive diagnosis. The impact of ultrasonography was defined based on the frequency with which the information resulting from this examination confirmed or denied the diagnostic suspicion made by the emergency physician on the basis of clinical and laboratory findings.

RESULTS

In 497/729 patients (69 %), ultrasound examination did not determine variations in the diagnostic and therapeutic pathways, either because it confirmed the outcome of clinical examination and laboratory tests, or because, even addressing in the opposite direction to these, the emergency physician did not consider its result because of being particularly alarmed or sufficiently reassured by clinical examination and laboratory tests. In the remaining 232/729 cases (31 %), ultrasound examination determined an increase or a reduction of the provided care and attention (subsequently proved justified in the vast majority of cases) in spite of what was initially assessed based on clinical examination and laboratory tests.

CONCLUSIONS

The results of our retrospective study demonstrated that ultrasonography was a valuable tool in the management of pediatric patients with acute abdominal pain together with clinical examination and laboratory tests.

Outpatient antibiotic use and the incidence of acute appendicitis in Finland: a nationwide study from 1990-2008

BACKGROUND

The incidence of acute appendicitis (AA) has decreased in Finland. We hypothesized that changing trends in outpatient antibiotic use might explain at least part of this declining incidence of AA.

METHODS

The number of all patients with AA in Finland was extracted from the national data base from 1990 to 2008. For comparison, the incidence of acute diverticulitis of the colon (AD) was also recorded. All outpatient prescriptions of antibiotics belonging to the major groups of these drugs were also recorded. We used unit root and co-integration analyses for statistical analysis of the data in the study.

RESULTS

The incidence of AA in Finland declined from 14.5 to 9.8 per 10,000 inhabitants (32%) and the incidence of AD increased by 47% between 1993 and 2007. The total outpatient use of antibiotics did not increase during this same period, but the use of antibiotics effective widely against colonic pathogens (macrolides, fluoroquinolones, and cephalosporins) increased significantly. No correlation was found between the incidence of AA, that of AD, and the use of different groups of antibiotics.

CONCLUSIONS

Our nationwide registry study indicated that changes in outpatient antibiotic use do not explain the decreasing trend in AA in Finland. Other factors, such as improved diagnosis of AA, may have some role in the decreasing incidence of AA.

Evaluation of the diagnostic accuracy of plasma markers for early diagnosis in patients suspected for acute appendicitis

OBJECTIVES

The main objective of this study was to evaluate the diagnostic accuracy of two novel biomarkers, calprotectin (CP) and serum amyloid A (SAA), along with the more traditional inflammatory markers C-reactive protein (CRP) and white blood cell count (WBC), in patients suspected of having acute appendicitis (AA). The secondary objective was to compare diagnostic accuracy of these biomarkers with a clinical scoring system and radiologic imaging.

METHODS

A total of 233 patients with suspected AA, presenting to the emergency department (ED) between January 2010 and September 2010, and 52 healthy individuals serving as controls, were included in the study. Blood was drawn and CP and SAA-1 concentrations were measured using enzyme-linked immunosorbent assay (ELISA). CRP and WBC concentrations were routinely measured and retrospectively abstracted from the electronic health record, together with physical examination findings and radiologic reports. The Alvarado score was calculated as a clinical scoring system for AA. Final diagnosis of AA was based on histopathologic examination. The Mann-Whitney U-test was used for between-group comparisons. Receiver operating characteristic (ROC) curves were used to measure the diagnostic accuracy for the tests and to determine the best cutoff points.

RESULTS

Seventy-seven of 233 patients (33%) had proven AA. Median plasma levels for CP and SAA-1 were significantly higher in patients with AA than in those with another final diagnosis (CP, 320.9 ng/mL vs. 212.9 ng/mL; SAA-1, 30 mg/mL vs. 0.6 mg/mL; p < 0.001). CRP and WBC were significantly higher in patients with AA as well. The Alvarado score was helpful at the extremes (<3 or >7). Ultrasound (US) had a sensitivity of 84% and a specificity of 94%. Computed tomography (CT) had a sensitivity of 100% and a specificity of 91%. The area under the ROC (95% confidence interval [CI]) was 0.67 (95% CI = 0.60 to 0.74) for CP, 0.76 (95% CI = 0.70 to 0.82) for SAA, 0.71 (95% CI = 0.64 to 0.78) for CRP, and 0.79 (95% CI = 0.73 to 0.85) for WBC. No cutoff points had high enough sensitivity and specificity to accurately diagnose AA. However, a high sensitivity of 97% was shown at 7.5 × 10(9) /L for WBC and 0.375 mg/mL for SAA.

CONCLUSIONS

CP, SAA-1, CRP, and WBC were significantly elevated in patients with AA. None had cutoff points that could accurately discriminate between AA and other pathology in patients with suspected AA. A WBC < 7.5 × 10(9) /L, with a low level of clinical suspicion for AA, can identify a subgroup of patients who may be sent home without further evaluation, but who should have available next-day follow-up.