Diagnostic reliability of pediatric appendicitis score, ultrasound and low-dose computed tomography scan in children with suspected acute appendicitis

Abstract

BackgroundDiagnosis of appendicitis in children is clinically challenging. Computed tomography (CT) is the gold standard for diagnosis; however, radiation exposure early in life is a concern with this technique. Therefore, in this study, we aimed to evaluate the diagnostic reliability of low-dose CT, pediatric appendicitis score (PAS), and abdominal ultrasound (US) in children with acute appendicitis, to reach a safe diagnosis.Patients and methodsThis retrospective study was conducted on 140 children who were admitted with clinically suspected acute appendicitis (45 with positive appendicitis and 95 children with negative appendicitis). Low-dose CT was performed, and PAS was retrospectively calculated for all subjects. US was initially performed for 38 subjects. All results were compared with the final diagnosis reached by an operative, histopathological analysis and follow-up.ResultsLow-dose CT showed a sensitivity, specificity, and accuracy of 97.8%, 100%, and 99.3%, respectively. At a cutoff value ≥5, PAS showed a sensitivity, specificity, and accuracy of 95%, 84%, and 89%, respectively. Abdominal US examination showed sensitivity, specificity, and accuracy of 55.6%, 85%, and 71%, respectively. Implementing Poortman’s model resulted in higher accuracy (92%) of US. There was a significant difference in accuracy between a low-dose CT and PAS on one side and between Poortman’s model and US examination on the other side. A diagnostic scheme was suggested using PAS as the excluding tool (PAS ≤2 send home and ≥7 send directly to operation) followed by US examination and reserving low-dose CT for inconclusive cases. This scheme would eliminate the use of CT for at least 33.7% and in 7 cases who had initial US examination.ConclusionAlthough CT remains the most accurate and less operator-dependent diagnostic tool for pediatric appendicitis, the radiation hazards could however be minimized using PAS as an excluding tool and US as the primary imaging modality followed by low-dose CT for inconclusive cases only.

Laboratory Tests in Addition to the Alvarado Score in the Management of Acute Appendicitis in School-Age Children

“…In a similar type of study has been conducted in Iran, where 67 patients were examined with LRQP and underwent appendectomy, diagnostic accuracy was 72.4% after US examination of abdominal organs with a compression test (Nasiri et al, 2012). Another study using US examination had accuracy of 92%, establishing strict criteria of US (Sayed et al, 2017). However, in the present study found, US examination accuracy was lower: sensitivity 67.7%, with specificity 76.9% and accuracy 71.9%.…”

Diagnostic performance of ultrasound to differentiate perforated from non‐perforated paediatric appendicitis: A narrative review

“…While ultrasound is a safe choice for first-line imaging in cases of suspected appendicitis due to lack of ionising radiation, 19 it is an operator-dependent imaging modality. 13 Variation of operator experience has been identified as a limiting factor of sonographic evaluation of appendicitis, 7,38 and due to its potential to cause variation of diagnostic performance between operators and across centres, it may be one of the reasons for the low sensitivity of ultrasound to differentiate between perforated and non-perforated appendicitis. 39 Two of the retrospective studies assessed inter-observer agreement among the radiologists reviewing the sonographic findings of appendiceal perforation.…”

“…[6][7][8] Perforation is typically defined as a hole in the appendix wall or the presence of an extraluminal appendicolith in the abdominal cavity, 3 and is important to identify because of its association with increased complications and morbidity. 9 Computed tomography (CT) has excellent diagnostic accuracy for identifying acute appendicitis [10][11][12][13] and can differentiate between non-perforated and perforated appendicitis. [14][15][16] However, there are concerns that the ionising radiation exposure of CT increases risk of cancer, 17 especially in children.…”

“…[14][15][16] However, there are concerns that the ionising radiation exposure of CT increases risk of cancer, 17 especially in children. 18 Although ultrasound is more operator dependent, 13 it is still preferred as the first-line imaging modality due to lack of ionising radiation, 19 with CT reserved for secondary imaging when ultrasound findings are equivocal in cases of suspected appendicitis. 13 Most studies have found ultrasound to demonstrate high specificity (91%-100%) and sensitivity (82%-98%) for diagnosing acute appendicitis, [19][20][21][22][23][24][25][26] though non-visualisation of the appendix or borderline findings usually results in an inconclusive ultrasound report.…”

“…18 Although ultrasound is more operator dependent, 13 it is still preferred as the first-line imaging modality due to lack of ionising radiation, 19 with CT reserved for secondary imaging when ultrasound findings are equivocal in cases of suspected appendicitis. 13 Most studies have found ultrasound to demonstrate high specificity (91%-100%) and sensitivity (82%-98%) for diagnosing acute appendicitis, [19][20][21][22][23][24][25][26] though non-visualisation of the appendix or borderline findings usually results in an inconclusive ultrasound report. 27 While there are accepted sonographic criteria for detecting acute appendicitis, 28,29 few recent studies have researched the reliability of ultrasound to differentiate perforated from non-perforated appendicitis.…”