Spotlight: baldness and alopecia

The pathophysiology of hair loss (alopecia) may include infectious, nutritional, congenital, autoimmune or environmental causes and can be temporary or long-lasting. Non-scarring alopecia includes androgenic alopecia (common hair loss), telogen effluvium (thinning of the hair), alopecia areata (spot baldness) and scarring alopecia discoid lupus erythematosus (a group of rare disorders that destroy hair follicles) or lichen planus (a type of non-infectious rash) caused by trauma or infections. Other hair follicle disorders include trichotillomania (hair pulling disorder), traction alopecia (gradual hair loss caused by pulling of hair), tinea capitis (fungal infection affecting the scalp) and hair shaft abnormalities. In androgenetic alopecia