ABSTRACT
During an emergency medicine call, you are asked to evaluate a patient brought to the emergency department for abdominal pain of unknown origin. On admission, the patient is nauseous. She has already vomited once before arriving at the hospital. You notice, on palpation, a tenderness in the right lower abdominal quadrant and a right-sided palpation pain during a rectal examination. The hematology laboratory draws your attention to mild leucocytosis. You establish a ‘working diagnosis’ of appendicitis. Because the patient is an otherwise healthy nulliparous woman of childbearing age, you will also consider a differential diagnosis because you do not want to miss an ectopic pregnancy, endometriosis or other problem associated with abdominal pain as an index manifestation on admission. You now find yourself in the middle of medicine’s logical discourse:
Clinical practiceLogical discourseEvidence You have just recorded history and
To solve this clinical problem, you need well-formulated arguments and a string of best possible evidences on which your postulates and conclusion (decisions and clinical orders) are based. The best possible evidence from a good clinimetric evaluation of abdominal and rectal pain and the information from the patient’s history are necessary for Postulate A. Your pattern recognition of the patient’s manifestations will probably be the fastest available evidence for your working diagnosis (Postulate B). Your knowledge of inclusion and exclusion criteria for competing diagnoses as well as that of overlapping and additional manifestations of competing diseases will help you order further tests to exclude competing diagnoses in such a differential diagnostic process or will help you follow the patient and perform surgery in case your working diagnosis is confirmed (Conclusion C).
