Patients With Profuse Hair Shedding May Reveal Anagen Hair Dystrophy: A Diagnostic Clue of Alopecia Areata Incognita

In a study of 1,932 patients with hair loss but no clear signs of classical alopecia areata, researchers discovered that some patients might actually suffer from alopecia areata incognita (AAI), which is often misdiagnosed as telogen effluvium (TE) or androgenetic alopecia (AGA). By using a modified wash test, they identified dystrophic anagen hairs—a sign of AAI—in 13 patients (3.2%) with TE, 54 patients (4.4%) with AGA + TE, but in none with pure AGA. Furthermore, 7 patients with TE and 32 with AGA + TE later developed alopecia areata patches within 6 to 9 weeks, while those with AGA did not. These findings suggest that the presence of dystrophic anagen hairs and subsequent development of alopecia patches in patients initially diagnosed with TE could indicate underlying AAI.