I think if there is a medical issue, it's very clear. My daughter actually suffers with something that has been mentioned, god knows what, since she was 5. Multiple visits to the dentist and doctor to try get to the bottom of it. 6 years later and we still don't have a remedy, so I do feel for people who suffer with something like this.
She has perfectly healthy teeth, great diet, no tonsil stones, doctor claims not to smell anything. The only thing that minimises the smell is copious amounts of water throughout the day and scraping the tongue but I'd love to know what can treat her breath because she is so self conscious of it and doesn't speak due to it.
So if that's how it affects my kid, I can imagine how Del conscious a client is in tho situation; treat it delicately.