I am very prone to infection, rashes and skin allergies. What can be the cause. My WBC count is 6500.

Can you explain? What kinds of infections, Champ? If you're getting rashes, you need to get the cause diagnosed. Everybody gets minor infections fairly often. Signs of immunodeficiency would be a few episodes of pneumonia, meningitis or vicious soft tissue infection landing you in the hospital. If you're getting skin allergy / contact dermatitis, a cause needs to be identified. Dermatology consult is in order.