Focal Atrichia: A Diagnostic Clue in Female Pattern Hair Loss

Focal atrichia, or small areas in the scalp without emerging hairs, is a common finding in female pattern hair loss (FPHL) and can be a helpful diagnostic clue. A study found that focal atrichia was seen in 44% of women with FPHL, particularly in the late onset subtype, compared to only 2% of those with other hair disorders. Biopsy findings of focal atrichia in FPHL showed primarily a more progressive miniaturization process than that of haired areas of the scalp. The study suggests that clinical clues, such as focal atrichia, are important in diagnosing FPHL as histology alone is rarely diagnostic.