First-line test for assessment of intussuseption

Intussusception is the main cause of intestinal obstruction in children aged between 3 months and 3 years (1). The clinical and instrumental diagnostic flow-chart for the children presenting with symptoms and sings favoring the possible diagnosis of intestinal intussusceptions is still matter of clinical investigation and debate. It is quite uniformly documented the high sensitivity and specificity of abdominal ultrasound (US) for detecting intussusceptions. Thus it is considered an ideal first-line diagnostic test directed to children possibly suffering of this condition (2). A recent investigation conducted by Weihmiller and co-workers on this matter and recently published in your journal terminated with the conclusions that the abdominal X-Ray (other than the abdominal US) is the instrumental investigation governing the entire subsequent diagnostic work -up of all children with possible intussusception and therefore that it should be obtained in every child suffering of this possible condition.(3) They support this statement highlighting the fact that abdominal X-Ray, despite having low sensitivity and specificity (77 % and 78% respectively), if included in a diagnostic flow-chart which consider also patient's age, bilious emesis, diarrhea, is essential to identify low risk cases of intussusception. Many reasons bring us to suggest to temper this recommendation. As the Authors openly declare, the abdominal X-Ray has a low specificity and sensibility, In fact, only slightly more than one third of the 90 patients with a positive abdominal X-Ray, ultimately turned out to have an intestinal intussusceptions. Furthermore, the overall implications of subsequent diagnostic work-up through which the remaining false positive cases underwent (for example the human and financial resources devoted to rule out the diagnosis; the human costs the patients and their families they had to pay for all this) are neither considered nor discussed in the paper. Finally, also the clinical relevance of the 8 false negative reports (8 out of 38 cases of intussusception) are not discussed. In face of all this also the data they presented confirmed the high sensitivity and specificity of abdominal US in this clinical setting. In fact, out of the 38 children who had an intestinal intussusceptions, 36 had a positive abdominal US. Furthermore, following the diagnostic flow- chart the Authors adopted, it emerged that actually the vast majority of the children who had an abdominal X-Ray ultimately ended up having also an abdominal US (211 of 299). In order to firmly affirm the importance of obtaining an abdominal X- Ray in every child presenting with a clinical picture suggestive of intussusceptions, it would be important to know the time interval which elapsed between the data of appearing of the first symptoms and the one of obtaining the X-Ray. In fact, in case of intussusceptions it has been well documented that the appearance of X-Ray sings of intussusceptions is a late event (1). This information is not provided in the paper. Another consideration that seems to suggest to temper the statement we are discussing is actually made by the Authors themselves. It regards the importance of the level of expertise of the child radiologist who interpreters the films. This means that the conclusion they reach can be applied only for those pediatric institutions which may benefit of a dedicated and expert pediatric radiologist. Finally, the most relevance concern regarding the Authors' recommendation is related to the fact that it brings a lot of children to be unnecessarily exposed to radiations, which, for an abdominal examination, are ten time more the dose a child has to tolerate for having a chest X-Ray. Only 38 of the 310 children (12%) who had an abdominal X- Ray ultimately turned out to be suffering of an intussusceptions. For all these reasons we believe the issue of which instrumental investigation should determine the diagnostic work-up of all children in whom an intestinal intussusceptions is suspected, remains matter of debate, thus all this allows us to confirm the policy adopted in our institution of always prioritizing the abdominal US for these children. The suggestions instead of starting the diagnostic work-up with on abdominal X-Ray could be limited to those institutions in which the abdominal US is not readily available. 1.Waseem M, Rosenberg HK. Intussusception. Pediatr Emerg Care. 2008 Nov;24(11):793-800. Review 2.Hryhorczuk AL, Strouse PJ.Validation of US as a first-line diagnostic test for assessment of pediatric ileocolic intussusceptions. Pediatr Radiol. 2009 Oct;39(10):1075-9. 3.Sarah N. Weihmiller, Carlo Buonomo and Richard Bachur. Risk Stratification of Children Being Evaluated for Intussusception.Pediatrics 2011;127