Last Update: 1/30/18 If you or someone you know has yellowed, thickened, cracked and/or swollen and inflamed toenails… it is caused from a fungus called onychomycosis [which literally means fungal infection of the nail]. Typically this disease is caused by a fungal tinea species and can also be caused by a candida yeast fungal species.  It is also possible to spread these tiny microorganisms to friends and family when good hygiene is not the standard. (more…)