Any ideas as to what would cause sudden loss of all hair (entire body) in an otherwise healthy 22 yo male?

Alopecia universalis: Is a genetically-predisposed autoimmune disorder in which hair loss is triggered by viral illness, trauma, or ? Stress. Hair re-growth is possible; albeit sporadic & unpredictable. Other autoimmune disorders may exist in the patient or family. Mutations in a gene on the short arm of chr. 8 cause congenital A.U. The national arthritis & musculoskeletal disorders website has more information.