When the Algorithm Fails and Experience Wins: An Extraordinary Trichoscopic Case

A 72-year-old woman with severe hair loss and a history of weak, brittle hair was initially misdiagnosed with alopecia areata, but trichoscopic examination revealed features more consistent with monilethrix, a congenital hair shaft dystrophy. The diagnosis was challenging due to the atypical spacing of hair shaft constrictions, which were unusually far apart. Treatment with oral minoxidil and minimizing mechanical hair trauma led to improved hair density and length. This case highlights the importance of thorough trichoscopic evaluation in distinguishing between alopecia areata and monilethrix, as their hair shaft constrictions differ in distribution and spacing.