Alopecia areata incognita (AAI) is a subtype of alopecia areata that closely resembles acute telogen effluvium (ATE), making diagnosis challenging.

Trichoscopic findings reveal numerous round or polycyclic yellow dots, regrowing hairs, and pigtail hairs.

Diagnosis is established upon clinical, trichoscopic, and histopathologic findings. A dermoscopy-guided biopsy in an area with multiple yellow dots is highly recommended.

In cases of diffuse hair loss, clinicians should consider AAI as a potential differential diagnosis and perform a dermoscopy-guided biopsy to avoid misclassification as telogen effluvium (TE) or androgenetic alopecia (AGA).