Recalcitrant Female Pattern Hair Loss Like Alopecia Unveils Unexpected Rare Entity

Marie-Unna hereditary hypotrichosis (MUHH) is an autosomal dominant disorder characterized by a specific pattern of hair loss. Initially described in 1925 by Marie-Unna in a German family spanning over seven generations, MUHH represents a previously unidentified form of congenital hypotrichosis. It typically presents as sparse hair at birth with a coarse texture, followed by regrowth during childhood then, finally, gradual hair loss at puberty, resembling pattern of androgenetic alopecia.

The study describes two cases from different unrelated families presenting with recalcitrant alopecia resembling female pattern hair loss, with dermoscopic findings consistent with pili torti and yellow dots. Genetic testing confirmed a heterozygous pathogenic variant in the HRURF gene, associated with autosomal dominant Marie Unna Hereditary Hypotrichosis. Up to our knowledge it is first case series reported from Egypt.

While recent literature on MUHH has primarily focused on identifying genetic abnormalities, there are other important questions that warrant consideration. These include histopathological studies, dermoscopic descriptions, and correlating types of genetic mutations with clinical presentations. These data might offer a deeper understanding of MUHH pathophysiology ending in efficacious treatment options.