Diane, have they tested for mycobacteria? Reason I ask is because that is usually a different sputum test than the regular one. it can take several weeks to get the results back. When I had a mycobacteria my lung function dropped dramatically (from the 70s to the 50s) and I had low grade fevers and night sweats. Maybe they've already done that, but it wouldn't hurt to ask. Thanks for the serum sickness link. I do hope you're able to get better soon! ~Juliet