Imaging and Laboratory Testing in Acute Abdominal Pain

As noted by almost every author in this issue, the diagnosis of emergency abdominal conditions involves the integration of information from the history, physical examination, laboratory testing, and imaging studies. Only rarely does the history or physical examination provide information that is conclusive or unequivocal, so that in most cases the clinician must resort to laboratory testing or imaging studies, which may themselves be equivocal or inaccurate. To prioritize and weight the information obtained from testing, it is important for the clinician to know the accuracy of the test being used. When discussing which laboratory tests or imaging to order in the setting of acute abdominal pain, it is convenient to organize information by disease process (eg, acute appendicitis, cholecystitis). Because studies on the accuracy of diagnostic tests are of necessity related to the presence or absence of specific diagnoses, and because clinicians frequently look to tests to help them rule in or rule out specific conditions, this article is organized by region of pain and common abdominal diagnoses. It focuses on the contributions that laboratory testing and imaging make in the emergency management of abdominal complaints as well as potential blind-spots and pitfalls that can arise if the tests are misapplied or misinterpreted.