Pattern hair loss: Pathogenesis, clinical features, diagnosis, and management

This chapter highlights the pathogenesis, clinical features, and state-of-the-art medical management of male pattern hair loss and female pattern hair loss (FPHL). Androgenetic alopecia (AGA) or pattern hair loss is by far the most common form of alopecia in men and women. The development and occurrence of AGA depends on genetic predisposition and an interaction of endocrine factors. The progression of patterned hair loss is the result of a gradual transformation of pigmented, thick scalp hair into fine colorless, almost invisible vellus-like hair follicles. Hair loss is patterned and nonscarring, with preservation of follicular ostia. Laboratory workup is usually not necessary in men with AGA unless there is concomitant diffuse hair loss. FPHL is a non-scarring alopecia with the preservation of follicular ostia. Scalp prostheses are practical for patients who are not candidates for hair restoration surgery, women with extensive hair loss, and/or patients without satisfying improvement after using medical therapy.