Procalcitonin(PCT) Guideline for ED. youtu.be/ZmJg105UiXk&list=PL… This guideline offers procalcitonin (PCT) recommendations for emergency departments to optimize antibiotic use and infection management. For lower respiratory infections, use antibiotics if PCT >0.25 ng/mL. In COPD exacerbations or febrile patients, PCT alone is insufficient. For acute pancreatitis, antibiotics are advised if PCT >1.0 ng/mL. In sepsis diagnosis, combine PCT with SIRS or qSOFA for accuracy. Post-gastrointestinal surgery, PCT may yield false positives but remains reliable after cardiac surgery or burns. For immunocompromised patients (e.g., neutropenia, lupus), PCT has low sensitivity. In bone/joint infections, PCT confirms but doesn’t exclude infections. For dialysis patients, PCT detects bacterial infections but is less effective in excluding peritonitis. In liver cirrhosis, PCT aids in diagnosing bacterial infections and peritonitis. For organ transplant patients, PCT is useful post-solid organ transplant but not post-stem cell transplant. Combining PCT with respiratory virus testing helps differentiate viral from bacterial infections, reducing unnecessary antibiotics. Overall, PCT is valuable but should be used alongside clinical judgment for optimal decision-making.