Friction can also contribute to the formation of folliculitis. Dr. Penzi adds that the most common cause is bacteria, but other common culprits include yeast and fungus (known as pityrosporum ...

The problem can also be caused by Malassezia, a yeast that often causes dandruff, seborrheic dermatitis, and folliculitis (inflamed follicles). Yeast naturally live on your skin without causing ...