I'm an NP who saw the following patient as an outpatient and referred him to ED for evaluation. The ED MD work-up diverged significantly from what I expected, making me think my pre-test for various problems was out of whack. I'm interested in what your ddx and work-up would be for this case? Appreciate your feedback. A 28 y/o male without significant past medical history was awoken from sleep around 3 a.m. by a left sided chest pain. Pain was continuous, worse with deep breath and with movement. No cough. No SOB at rest. He rides bike as his only means of transportation and found that when he rode later in the day his pain increased and he felt very short of breath. After getting out of bed he noted that he felt lightheaded at times while up and moving around. In the early afternoon he developed a fever to 101 F. I saw him after no improvement at at about 19:30. No hx of similar. No personal or fhx of DVT, PE, PTX, lung disease. No DVT risk factors. No regular meds. Took some type of herbal remedy for fever. PE: T 101, HR 94-97 (he thinks his resting HR usually 60-70), RR 20, BP 96/64 (usually 120s systolic), SPO2 96-97% on room air at rest. NAD. I though maybe his external jugular veins were a bit prominent at 90 degrees. RRR, no murmur. CTAB. His right calf may have been slightly larger than left, but no obvious sign of DVT. In the ED he was still febrile, initial HR 104 bpm, BP 104/64, otherwise comparable vital signs.