Folliculitis is described as the inflammation of the hair follicle. The hair follicle is the region of the skin that grows hair by packing old skin cells together. Folliculitis can literally affect any part of the body. However, it is more commonly seen to occur and lead to itchy bumpy rash on face, underarms, back of the knee, etc. Actually, folliculitis is found to affect the skin which is subjected to shaving, rubbing, and friction with clothes and jewelry.