Difference of scalp folicullitis and scalp acne?

Same thing.: Scalp folliculitis is an inflammatory disorder of the hair follicles in the scalp, and is also sometimes called "acne necrotica", which is why it is sometimes confused with acne, which does not occur on the scalp (except along the frontal hairline). In other words, the condition often called "scalp acne" is actually folliculitis, or inflammation/infection of hair follicles.