Consider a visit to the podiatrist. Toenails that have changed in texture and have lifted from the underlying nail bed have the potential to be infiltrated by fungus as well as other organisms including bacteria, virus and yeast. Have your toenails examined and culture can be taken to determine if the toenail has an infection. Causes for changes in the toenail stem from trauma to systemic diseases. A proper examination will include clinical assessment of the toenails as well as a thorough questioning of your medical history.