Pediatric emergency medicine trisk 1592 1592

urgent radiologic workup. For example, abdominal pain and bilious vomiting in
an infant requires supine and upright plain films, as well as a limited upper GI
series for evaluation of congenital obstructive anomalies such as malrotation. A
child with paroxysms of colicky abdominal pain and grossly bloody stools
requires immediate ultrasound for rapid diagnosis of intussusception, or in clearcut cases should proceed directly to an air-contrast enema for both diagnosis and
reduction of the intussusception. Other situations require no imaging studies (e.g.,
a typical case of viral gastroenteritis). In many cases, cultures or serum chemical
analyses are essential for making a diagnosis (e.g., meningitis, aspirin toxicity,
urinary tract infection [UTI], pregnancy) or for guiding management (e.g., degree
of metabolic derangement in severe dehydration, pyloric stenosis, diabetic
ketoacidosis). For most straightforward, common illnesses (e.g., gastroenteritis,
respiratory infections with posttussive emesis), laboratory investigation is
unwarranted.