Infiltrates...explain more.../lab interpretation

ok....this past week a pt at work had a cxr...which is nothing uncommon for any of them...some get them yearly for the md progress note/checkup, some get it for a sick call if they have cough/fever/congestion.....you know the drills.....anyhow...a pt who has a dx of chf and copd had IM lasix, wts ordered, and a cxr...thats how our md usually does it. she had no cough, no congestion, no sob, no wheezing, no fever...nothing except swollen feet (chf....go figure right?) ...she sits in her recliner all the time and reads alot w/o putting her feet up. she is also followed by hospice palliative care......and her daughter in law is always coming in and asking the same old ?'s over and over and over and over and over and over .....this drove me absolutely insane for over 3 nights! all of us explained the exact same thing to her. ....still didnt get it. anyhow....the cxr showed the usual.....cardiomegaly, old scarring, and an improved infiltrate....probably from that lasix also.....my ? is this.....does an infilitrate necessarily mean pneumonia? ive seen pts who have chronic ones...it shows up on all their cxr's...the ones who have really bad copd and chf are the ones i have normally seen it in. sometimes the doc doesnt order antibiotics for this stuff if there is no fever or increase in other s/s like congestion or wheezing etc. how do you guys interpret which labs you call the doc? what i normally do is compare result A with the most recent result prior...if it is a significant change ...i call it....otherwise it goes in his box for him to see himself.....plus i see if they have a supporting dx for labs also..that are out of whack...like chronic anemia etc. etc.