The Community Acquired N Pneumonia Guidelines

Most community acquired pneumonia, which means that it is pneumonia, not acquired 48 hours after hospitalization or while in a ventilator, is either bacterial or viral. The rule of thumb is that the sicker they are, the more aggressively you're going to treat and evaluate. In pneumonia, less than 10% of blood cultures are positive; even lower in outpatient setting. So for non-severe pneumonia, you don't need to do a lot of treatment,. You need to put them on the right empiric antibiotics and observe the course and see if they respond as you expect them to  and their symptoms improve.