Just anecdotally from my IM training here were some common ones, not necessarily in any particular order:
-Infections including sepsis (very general I know) -> Pneumonia, UTI, abscesses, viral syndromes
-SOB
-Chest Pain
-Arrhythmias/palpitations
-COPD
-CHF
-CVA/TIA
-Abd pain/intra-abd pathology -> gastritis, colitis, acute choley, pancreatitis, appendicitis, etc...
-Syncope/fall
-Fracture
-Intractable MSK pain
-Bleeding/anemia
-AMS
-Hyper/Hypoglycemia/Diabetic emergencies
-Overdose
-Failure to thrive/"needs placement"
-Intracranial hemorrhage/headache
-Fever unknown origin
-Cardiac arrest
-DVT/PE
-Acute issues related to malignancy and chemo treatment