To be honest, I never took a microbiology course in my life - it is all experiential - and I do a bit of research from time to time.

There are some exceedingly slow-growing mycobacteria, but as far as I know, none is a threat to our lungs. (Over 100 types have been isolated, but there is little research on many of them.) There are also some slow-growing nocardia and rhodococcus, but these are mainly threats in immunocompromised people. I'm not sure how long they take to grow.

Like your daughter explained, almost every culture yields surprises. Most are not known to be a problem in humans, and are often omitted in the pathology results we see om My Chart.

What does your doc have to say about the "mystery bug"? Curious (aka nosy" minds would like to know.
Sue