Recently we had a patient admitted for a diagnosis that did not really fit his problem representation. The diagnosis was a convenient one, and easily treated. He initially responded to treatment, and we discharged him. The diagnosis assumption nagged at me, but I did not push forward with a test that my mind wanted. A week later he returned (the dreaded readmission), with the same symptoms. The admitting resident expanded the treatment for the same diagnosis. The next morning on seeing the patient, we were even more uncomfortable than on the first admission. As often happens, this is a story of community-acquired pneumonia (CAP) that was not CAP. We ordered a CT scan that clarified the abnormal X-rays. We reviewed the chest X-rays and CTs with the radiologist. His symptoms never fit CAP. His X-ray could have been CAP. Only the CT scan pointed us in the right direction. I preach expanding the diagnostic evaluation when the problem representation and the illness script do not match. Yet, doing so is often difficult. Our patient’s diagnosis was delayed a week, with continued discomfort for that entire week. So I am challenging myself. I “knew” that we did not have the right diagnosis, but “I did not pull the trigger.” I am not unusual. I suspect we all suffer from this error. The second time I had no hesitation. How do I convince myself to honor my instincts in such patients? I suspect you all have experienced similar situations. This story (and I have withheld some details for patient confidentiality) likely seems rather common to others. I hope to do better the next time. Part of not doing better is refusing to rationalize what happened, but rather learn from the experience. The patient improved dramatically when we treated the right process. Robert Centor is an internal medicine physician who blogs at DB’s Medical Rants. Source