Tricho-hepato-enteric syndrome: Microscopic analysis of the hair shaft showing breaks located at nodes in the hair (trichorrhexis nodosa) and longitudinal breaks.
Trichorrhexis nodosa is a defect in the hair shaft characterized by thickening or weak points (nodes) that cause the hair to break off easily.[2][3]: 636 This group of conditions contributes to the appearance of hair loss, lack of growth, and damaged-looking hair.
Trichorrhexis may have a genetic basis but appears to be precipitated by environmental factors. Among Caucasians the defect often appears at the ends of the hair shaft with splitting of the ends, thinning and whitish discoloration.
These conditions are directly related to environmental causes such as "perming", blow drying, aggressive hair brushing, and excessive chemical exposure.
Improving environmental factors will reduce damage to the hair. Gentle brushing with a soft brush should replace more aggressive brushing, ratting, or other procedures. Harsh chemicals such as hair straightening compounds and permanents should be avoided. The hair should not be ironed. Excessively harsh shampoo should be avoided. Hair conditioners should be used.[citation needed]
^James, William D.; Elston, Dirk; Treat, James R.; Rosenbach, Misha A.; Neuhaus, Isaac (2020). "33. Diseases of the skin appendages". Andrews' Diseases of the Skin: Clinical Dermatology (13th ed.). Edinburgh: Elsevier. p. 764. ISBN978-0-323-54753-6.
^Freedberg, et al. (2003). Fitzpatrick's Dermatology in General Medicine. (6th ed.). McGraw-Hill. ISBN0-07-138076-0.
