Etiology and diagnosis of androgenetic alopecia

Androgenetic alopecia is a common form of hair loss caused by genetic and hormonal factors. It affects both men and women and is characterized by the miniaturization and involution of hair follicles, resulting in thinner and shorter hair. Diagnosis is typically made through clinical examination and scalp biopsy, which can reveal decreased numbers of terminal anagen follicles and increased numbers of telogen follicles. The severity of hair loss can vary from mild to severe and is classified by Hamilton's classification for men and Ludwig's classification for women. Diagnosis involves a medical history and physical examination, including a hair pull or pluck to check for excessive telogen hair fibers. Treatment options include medications such as finasteride and minoxidil, as well as hair transplant surgery.