Normal vs Compound Follicles

What is the difference?

Hairs emerge from the scalp through pores or hair follicle openings. Some pores have just one hair, but most normally have two or three hairs emerging through a single hair follicle opening. This is completely normal. 
It’s important to be able to quickly spot when something is not quite right. Most hair loss conditions lead to a reduction in the number of hairs coming out of each pore. Instead of seeing the plentiful bundles of two and three hairs one starts to see pores with either no hairs at all or just a single hair. 
Some scarring alopecias are associated an unusual feature- and that is an increase in the number of hairs coming out of the pores. When six or more hairs come out of a single opening we refer to this as a “compound” follicle. The scarring alopecias which frequently show compound follicles include folliculitis decalvans (tufted folliculitis) and sometimes acne keloidalis. It tends to be the scarring alopecias associated with neutrophils that are associated with formation of compound follicles.

Compound follicles occur because of the destructive enzymes released from the inflammatory process. These enzymes destroy tissue and promote fusion of follicles together. The photos here show compound follicles in folliculitis decalvans and single haired follicles in lichen planopilaris. 

SINGLE HAIRS IN LICHEN PLANOPILARIS

COMPOUND HAIRS IN FOLLICULITIS DECALVANS