Practical Guidelines for Evaluation of Loose Anagen Hair Syndrome

In a retrospective survey of 374 patients with alopecia, 10% were diagnosed with loose anagen hair syndrome (LAHS), predominantly affecting young girls with a mean age of onset at 2.8 years. The study highlighted that LAHS is a common cause of nonscarring alopecia, characterized by thin, sparse hair, and is often diagnosed using a trichogram, which was effective in 32 of 33 patients. The study recommended performing a hair-pull test before extensive blood testing in young girls with diffusely thin hair to confirm LAHS and potentially avoid unnecessary tests and stress. While LAHS may be associated with genetic syndromes and potentially linked to a K6HF mutation, most cases resolve spontaneously, though minoxidil therapy can be used in severe cases. The guidelines suggest a high suspicion for LAHS in young children with sparse hair and the use of a hair-pull test and trichogram for diagnosis, reserving topical minoxidil for more severe cases.