Suspicion of appendicitis in pregnant women: emergency evaluation by sonography and low-dose CT with oral contrast
To evaluate non-intravenously enhanced low-dose computed tomography with oral contrast (LDCT) for the assessment of pregnant women with right lower quadrant pain, when magnetic resonance imaging (MRI) is not immediately available.
One hundred and thirty-eight consecutive pregnant women with acute abdominal pain were admitted in our emergency centre. Thirty-seven (27%) of them, with clinical suspicion of acute appendicitis, underwent abdominal ultrasonography (US). No further examination was recommended when US was positive for appendicitis, negative with low clinical suspicion or showed an alternative diagnosis which explained the clinical presentation. All other patients underwent LDCT (<2.5 mSv). Standard intravenously enhanced CT or MRI was performed when LDCT was indeterminate.
Eight (22%) of 37 US exams were reported normal, 25 (67%) indeterminate, 1 (3%) positive for appendicitis, 3 (8%) positive for an alternative diagnosis. LDCT was obtained in 29 (78%) patients. It was reported positive for appendicitis in 9 (31%), for alternative diagnosis in 2 (7%), normal in 13 (45%) and indeterminate in 5 (17%). Further imaging (standard CT or MRI) showed appendicitis in 2 of these 5 patients, was truly negative in 1, indeterminate in 1 and falsely positive in 1. An appendicitis was confirmed at surgery in 12 (32%) of the 37 patients. The sensitivity and the specificity of the algorithm for appendicitis were 100% (12/12) and 92% (23/25), respectively.
The proposed algorithm is very sensitive and specific for detection of acute appendicitis in pregnant women; it reduces the need of standard CTs when MRI is not available as second-line imaging.
• In pregnant women, US is limited by an important number of indeterminate results
• Low-dose CT can be used after an inconclusive US for the diagnosis of appendicitis in pregnant women
• An algorithm integrating US and low-dose CT is highly sensitive and specific for appendicitis in pregnant women
KeywordsAppendicitis Pregnant women Tomography, X-ray computed Radiation dosage Emergencies
Authors wish to thank Gabriel Guglielmi M.D., from the Department of Radiology, University Hospital of Geneva, for his contribution to data collection
The authors state that this work has not received any funding.
Compliance with ethical standards
The scientific guarantor of this publication is Prof. Pierre-Alexandre Poletti.
Conflict of interest
The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article.
Statistics and biometry
No complex statistical methods were necessary for this paper.
Written informed consent was waived by the Institutional Review Board, because of the retrospective nature of the study.
Institutional Review Board approval was obtained.
• observational study
• performed at one institution
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