Bjornstad Syndrome With Late-Onset Alopecia Mimicking Androgenetic Alopecia: Histopathological and Genetic Findings

This study presents a unique case of Björnstad syndrome (BS) with late-onset alopecia mimicking androgenetic alopecia (AGA) in an 18-year-old female. BS is a rare autosomal recessive disorder characterized by pili torti and congenital sensorineural hearing loss, linked to BCS1L gene mutations. The patient exhibited progressive alopecia and hearing impairment, with genetic testing revealing compound heterozygous pathogenic variants in BCS1L. Histopathological analysis showed unique features like crescent-shaped hair shafts and follicular fibrosis. Treatment with baricitinib and minoxidil improved hair density and reduced hair fracturing, suggesting JAK inhibition may aid in managing BS. This case expands the understanding of BS's clinical and genetic spectrum and highlights the importance of considering BS in differential diagnoses of patterned hair loss in young individuals.