Ultrasonography in diagnosis of appendicitis and its complications in pediatric patients: a cross-sectional study

Contemporary ultrasound, computed tomography, or magnetic resonance imaging for acute appendicitis diagnosis in children and adolescents: systematic review and meta-analysis

BACKGROUND

Since the last publication of meta-analyses on pediatric acute appendicitis imaging in 2016 and 2018, ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) technology and protocols have improved, and there are new reports on their accuracy.

OBJECTIVE

We determined sensitivity, specificity, and diagnostic odds ratios (DOR) of the US, CT, and MRI for pediatric acute appendicitis, in studies published from 2015 to 2024.

MATERIALS AND METHODS

PubMed, MEDLINE, BVS, OVID, Web of Science, and Trip Database (Jan 2015-May 2024) were searched for studies in patients less than 21 years old with suspected acute appendicitis. Histopathology and clinical follow-up were the reference standard. Those with insufficient data for a 2 × 2 contingency table were excluded. QUADAS-2 directed risk of bias assessment. Data were extracted for meta-analysis.

RESULTS

Our review of 37 articles included 22 conventional US studies (20,897 patients), 4 point-of-care US (POCUS) studies (280), 4 CT studies (1,389), and 13 MRI studies (2,630). Pooled sensitivity, specificity, and DOR were: conventional US: 0.93 (95% CI [0.87, 0.96]), 0.89 (95% CI [0.80, 0.95]), 115.23 (95% CI [-32.88, 263.34]); POCUS: 0.80 (95% CI [0.61, 0.91]), 0.93 (95% CI [0.83, 0.98]), 53.97 (95% CI [-39, 146.94]); CT: 0.96 (95% CI [0.93, 0.97]), 0.98 (95% CI [0.96, 0.98]), 864.43 (95% CI [264.02, 1,464.84]); MRI: 0.96 (95% CI [0.94, 0.97]), 0.98 (95% CI [0.96, 0.99]), 1,030.42 (95% CI [222.05, 1,838.8]). No statistically significant differences were found (P = 0.07). For quantitative synthesis, US and POCUS studies had the highest heterogeneity.

CONCLUSION

All four modalities have high diagnostic accuracy.

REGISTRATION

PROSPERO: CRD42024538086. May 5, 2024. Retrospectively registered. PROSPERO registration name: Ultrasound, computed tomography or magnetic resonance imaging for diagnosing acute appendicitis in children and adolescents.

The utility of sonographic signs to diagnose simple and complicated appendicitis in children

BACKGROUND

Acute appendicitis is classified into simple (SA) and complicated (CA). Ultrasound scans (USS) can be useful in clinically equivocal cases, by visualising primary and secondary signs. This study explores the utility of sonographic signs to diagnose and differentiate appendicitis in children.

METHODS

Single-centre retrospective cohort study over a 2-year period. Consecutive USS for suspected appendicitis were included; sonographic signs were extracted from standardised institutional worksheets. USS results were compared with pre-defined intraoperative criteria for SA and CA, confirmed with histological analysis. Data are reported as median [interquartile range], percentages (number), area under the curve (AUC), conventional diagnostic formulae and adjusted odds ratios following multiple logistic regression (p < 0.05 considered significant).

RESULTS

A total of 934 USS were included, with median age 10.7 [8.0-13.4] years, majority were female (54%). One quarter (n = 226) had SA, 12% (n = 113) had CA, 61% (n = 571) had no appendectomy and 3% (n = 24) had negative appendicectomy. Appendix visualisation rate on USS was 61% (n = 569), with 62% (n = 580) having a conclusive report. Sonographic signs suggesting appendicitis included an appendiceal diameter > 7 mm (AUC 0.92, [95% CI: 0.90-0.94]), an appendicolith (p = 0.003), hyperaemia (p = 0.001), non-compressibility (p = 0.029) and no luminal gas (p = 0.004). Secondary sonographic signs included probe tenderness (p < 0.001) and peri-appendiceal echogenic fat (p < 0.001). Sonographic signs suggesting CA over SA comprised a diameter > 10.1 mm (AUC 0.63, [95% CI: 0.57-0.69]), an appendicolith (p = 0.003) and peri-appendiceal fluid (p = 0.004).

CONCLUSION

Presence of specific sonographic signs can aid diagnosis and differentiation of simple and complicated appendicitis in children.

Pre-Coronavirus Disease 2019 Pediatric Acute Appendicitis: Risk Factors Model and Diagnosis Modality in a Developing Low-Income Country

PURPOSE

Pediatric acute appendicitis has a stable incidence rate in Western countries with an annual change of -0.36%. However, a sharp increase was observed in the Asian region. The Indonesian Health Department reveals appendicitis as the fourth most infectious disease, with more than 64,000 patients annually. Hence, there is an urgent need to identify and evaluate the risk factors and diagnostic modalities for accurate diagnosis and early treatment. This study also clarifies the usage of pediatric appendicitis score (PAS) for children <5 years of age.

METHODS

The current study employed a cross-sectional design with purposive sampling through demographic and PAS questionnaires with ultrasound sonography (USG) results. The analysis was performed using the chi-square and Mann-Whitney tests and logistic regression.

RESULTS

This study included 21 qualified patients with an average age of 6.76±4.679 years, weighing 21.72±10.437 kg, and who had been hospitalized for 4.24±1.513 days in Siloam Teaching Hospital. Compared to the surgical gold standard, PAS and USG have moderate sensitivity and specificity. Bodyweight and stay duration were significant for appendicitis (p<0.05); however, all were confounders in the multivariate regression analysis. Incidentally, a risk prediction model was generated with an area under the curve of 72.73%, sensitivity of 100.0%, specificity of 54.5%, and a cut-off value of 151.

CONCLUSION

PAS outperforms USG in the sensitivity of diagnosing appendicitis, whereas USG outperforms PAS in terms of specificity. This study demonstrates the use of PAS in children under 5 years old. Meanwhile, no risk factors were significant in multivariate pediatric acute appendicitis risk factors.