Is Pro-Calsitonin a Good Diagnostic Test for Pneumonia?

In general practice, often it's about 80% of the time we don't know what causes pneumonia. Sending a million diagnostic tests are often going to be negative. Sputum cultures and pro-calsitonin should only be sent if someone is severely ill or has a risk of antibiotic resistance. urinary strep and legionella antigen tests can also be helpful in some cases.