I find this very hard to believe. What I could believe is that the healing process may accentuate the problem temporarily and if you don't fast long enough, you may be left in a partial state of healing, which may appear that you are worse than before.
I've had a rash that was accentuated during fasting, most likely detox, and if I break the fast before the rash is healed, it lingers around for awhile seeming as if I was worse than before.