From what I have read on the subject, skin problems come from the gut. Obviously you were already having problems with your gut for this yeast skin disease to develop in the first place. The Antibiotics you have taken have killed of what good flora you had left and the yeast is now completely out of control as a result.
candida is now getting into your body causing the severe problems you are getting. The remedy is to heal the gut and reintroduce friendly florer to keep the yeast under control. With improved diet, probiotics and fermented foods it is possible. Not an easy task but it can be done.
Once you have candida under control the rash will eventually
disappear. Some people have used caster oil with great success.
At least this is a possibility. Good Luck with your health.