Is PIILIF the Precursor to Scarring Alopecias?

PIILIF was identified in the normal-appearing scalp (NAS) zones of all AKN patients.

A single root condition called PIILIF (perifollicular infundibulo-isthmic lymphocytic infiltrates and fibrosis) may be a precursor for acne keloidalis nuchae (AKN) and primary cicatricial alopecias, according to a study in Clinical Cosmetic and Investigational Dermatology. 

PIILIF was identified in the normal-appearing scalp (NAS) zones of all AKN patients. PIILIF could shed light on early AKN and scarring alopecia stages.

“Our findings, along with other studies, suggest that PIILIF potentially links all common scarring alopecias, such as AKN, folliculitis decalvas (FD), lichen planopilaris (LPP), frontal fibrosing alopecia, and central centrifugal cicatricial alopecia,” says study author Dr. Sanusi Umar of the Dr. U Hair and Skin Clinic in Manhattan Beach, Calif. “This highlights their interconnections, offering new insights into their origins and enabling a more holistic diagnostic and therapeutic strategy. Moreover, this might streamline the intricate classification of scarring alopecias by reducing redundancies in closely related conditions. For instance, our research questions the necessity of the entity currently designated LPP-FD phenotype."

The study also found AKN to be more prevalent than previously realized in European-descended White males (10% of patients), often unnoticed or misdiagnosed as nape irritation or dandruff. This finding challenges AKN's perception as solely affecting people with darker skin tones.

Further research is needed to uncover PIILIF's mechanisms, triggers, and role in hair loss, Dr. Umar notes.