For years, I'd cultured Pseudomonas and MRSA. I've now had 3 cultures without Pseudomonas and my last culture didn't have MRSA either, but had "rare yeast" too with no other abnormal airway flora. This is the first time I cultured it. My doctor is not concerned at all and is, in fact, extremely excited that I'm 3 cultures PA negative and now am not culturing MRSA either. I've also had a massive upswing in my FEV1. He said culturing yeast is very common, it's usually transient and is probably just growing in there because nothing else is at the moment. He said it may have even hitched a ride on the sputum I coughed up for the sample from my mouth or throat. I know some people have problems with it, but I'm clearly not at all.