This is characterized by a perception of hair loss that actually results from increased hair breakage often very close to the scalp (6). The patient presents with a single episode of claimed hair loss that may affect either the whole of the scalp or one of more poorly defined areas. When associated with a specific chemical treatment, hair breakage often begins several days after the causative procedure. Traction alopecia or other hair pulling dystrophies should also be excluded.
Investigation: True hair loss from the follicle rarely, if ever, occurs due to cosmetic practices. If present, then associated skin inflammation or scarring would be expected. Close inspection of the scalp may reveal short, broken fibers. Routine light microscopy of the shed fibers normally shows a fracture or trichorrhexis nodosa brush break at the proximal end. The distal end can present either as damaged, or often as a clean scissor cut, particularly when a haircut has preceded a chemical treatment.
