Rash. This sounds like a form of eczema that may result from irritation in the sweat glands, called dyshdrotic eczema. The can become infected with bacteria or fungal infections. Stronger cortisone creams, obtained by prescription, along with appropriate medications for infection will be offered when you see your physician.
Every so often my hands break out in itchy bumps that turn into blisters and leak. What could this be?
Contact or irritant. Both contact allergens and irritants (soap, cleanser etc) can cause this type of skin problem. If you wash your hands too often, you may irritate the skin as well. Try avoiding using scented or antibacterial soap. Apply hand lotion after washing hands. Avoid irritants (wear non-latex gloves when washing). Topical hydrocortisone cream may help. See dermatologist if problem persists.
Contact dermatitis. Could explain the rash in your hands. Most common source are strong kitchen soaps. Use kitchen gloves in the sink. Please contact a dermatologist if avoidance of this soap does not eliminate the rash.