I would try switching detergents just to be sure. Maybe she doesn't react to the detergent alone, but maybe it's something in her urine that's reacting with the detergent and irritating her?

Also have her checked for bacterial infections like impetigo or yeast. Impetigo especially usually leaves blisters like that...

Karen.

Remember also that you still might be able to use the Charlie's on regular clothing, even hers. Clothing and diapers are different in many ways so what affects her genital area skin when used on a diaper may not affect the rest of her body when used on regular clothing.

Or maybe try rinsing the heck out of the diapers when you use the Charlie's. Not necessarily a good long-term solution (waste of water and energy) but it might help during the healing period and might also help confirm or elliminate the Charlie's as the source of the problem. Is there a particular reason you're using borax? I know you mentioned that you had that tested as well but unless you have a real 'need' for it, you could try elliminating it to see if it helps. Same for the vinegar if you can. The simpler the better kwim? Too many ingredients makes it hard to nail down the exact issue.

From what I know of impetigo it can indeed be quite contagious but I would definetly not dismiss it just because it hasn't spread. From what I've read, the liquid inside the blister would be thick and honey-like and then it would form yellow crusts when it bursts.

In the same kind of quest for simplicity and determining the problem, maybe switch to all disposables for a little while if you can afford it (or maybe only at night if you suspect the nighttime diapers are the culprit). You mentioned that it always seem to help so maybe stick with it for a while, give her skin a chance to totally heal. Then if the rash continues you'll know for sure it's not the cloth diapers or your detergent. If the rash disappears, give the skin a good chance to heal completly (so you can elliminate the possibility that it was something as simple as a particularly nasty poop that irritated some still broken skin kwim?). Then try the cloth again and see how it goes. If the rash returns then you'll know it's something to do with the diapers themselves and can investigate that further.

Oh, and you mentioned that yeast treatments hadn't helped. Did you keep using the same cloth diapers while you administered the treatment? Because if so the yeast could theoretically be in the diapers and reinfecting her everytime. It's not always necessary (I successfully treated yeast on my first dd without having to treat the diapers too) but since you're having ongoing problems it might be worth thinking about. To treat diapers you need either an anti-fungal agent (tea tree oil, bleach, perhaps vinegar although it's not necessarily always 100% effective) or high heat. High heat is tricky with fitted diapers because of the elastic and snaps but involves either boiling or ironing. I might reserve bleaching or the high heat as last-ditch efforts if you're ready to chuck the diapers cause nothing else is working (all three could potentially cause harm to the diapers).

One last piece of advice, it might be time to take a really systematic approach to this. Start with a certain base (in how you wash the diapers, the foods you give her etc etc) and then change one thing at time to see what happens. Keep track of the changes you've made (write them down if you have to) and see what happens. By changing or adding just one thing at a time you can really pinpoint what helps and what makes things worse.

Karen.