No pictures please - enough of plain abdominal radiographs
Tops, S.C.M., Meulen, C.G. ter
Locatie(s): Auditorium 1
Categorie(ën): Plenaire sessie; Presentations "Schop de Heilige Huisjes omver!"
Moderator:
Mw. dr. H.A.H. Kaasjager, Arnhem
Panelleden
Mw. dr. P.C. Oldenburg, Amersfoort
Mw. W.E.M. Schouten, Amsterdam
Dr. F.L.J. Visseren, Utrecht
Background: Acute abdominal pain accounts for 5-10% of the visits to the emergency department in the Netherlands. Medical decision making in patients with abdominal pain based on clinical and laboratory evaluation alone can result in unnecessary interventions or delayed treatment. Therefore additional diagnostics in this patient population are often required.[1,2] In the 70’s nearly 43% of all patients with acute abdominal pain had plain abdominal radiography. Now, 40 years later, in 20% of these patients an abdominal X-ray is performed, while over the years more and more accurate diagnostic instruments such as ultrasonography and computed tomography (CT) have become available.[3] Although plain X-ray is relatively cheap, quick available and has low exposure to radiation, the question is whether there is still an indication for this investigation in the evaluation of patients with acute abdominal pain.
Research question: What is the diagnostic accuracy of plain abdominal radiography in patients with acute abdominal pain (compared to ultrasonography and CT)?
Methods: A structured search on PubMed Central database was conducted using the following search terms: ‘Abdominal Pain [Mesh] AND Radiography, Abdominal [Mesh]’ and ‘Abdominal Pain [Mesh] AND Plain abdominal radiography’. Limits were set to English language, full text available and article type (inclusion of randomized controlled trials, (controlled) clinical trials, (systematic) reviews and multicenter studies). Of each relevant publication found, the related citations in PubMed and the reference list of the article were screened for other relevant articles. Also a search on UptoDate was performed on indications often used for plain abdominal radiography. Search terms were ileus, urolithiasis, bowel obstruction, foreign body, constipation and bowel perforation.
Results: The search on PubMed Central database yielded 103 articles of which 5 articles were found relevant: 3 reviews and 1 multicenter study performed in the Netherlands (2 articles referred to this study). Screening of the related citations in PubMed and the reference list of each article resulted in another 11 relevant articles. The search in UptoDate resulted in 5 relevant items.
Abnormal plain radiographs
Plain abdominal radiographs are abnormal in only a minority of cases. Between 10-22% of all patients with acute abdominal pain have abnormal findings on plain X-ray as foreign bodies, signs of obstruction or urinary stones.[4-7] In patients with diffuse, nonspecific abdominal pain or with complaints of nausea and vomiting abdominal X-ray is mostly (98%) normal.[5] When an abnormality is noted on abdominal X-ray in only 1 on 10 patients initial clinical diagnosis is changed. However in the vast majority (78%) these changes are not accurate.[2] Besides, in case of surgical treatment CT is needed in preoperative planning to provide information about size, cause and location of the problem.[2,8] This is another shortcoming of plain abdominal investigation. The only exception is an ingested foreign body: there is no evidence available that CT has a higher sensitivity and specificity than plain abdominal radiography to establish this diagnosis. Though the advantage of CT remains the ability to provide information about the location of the foreign body, which is a prerequisite when surgical treatment is planned.[6,9]
Normal plain radiographs
A normal abdominal X-ray can be misleading in the work-up of acute abdominal pain. Because of its low sensitivity a normal plain abdominal investigation can not rule out diseases.[6,8,10-16] In a study in which all patients with acute abdominal pain whose abdominal X-ray results were normal had follow-up imaging (ultrasonography or CT) 72% of these showed abnormal findings.[13] Beside a better diagnostic accuracy an important advantage of ultrasonography and CT compared to abdominal X-ray lies in the possibility of providing an alternative diagnosis.[6,8,10-16]
More arguments…
In a Dutch prospective multicentre study[2] the added value of different diagnostic modalities was evaluated after clinical and laboratory evaluation. In approximately 1000 patients at the emergency department with abdominal pain more than 2 hours and less than five days duration, no improvement in diagnostic accuracy was seen with plain abdominal radiography compared to clinical assessment alone. CT after negative or inconclusive ultrasonography resulted in the highest overall accuracy. This shows once again that in the diagnostics of patients with acute abdominal pain abdominal X-ray should be replaced by ultrasonography or CT.
Conclusion: There is abundant evidence that in the work-up of patients with acute abdominal pain, plain abdominal radiography is obsolete.
