Hair Casts or Pseudonits

The document discussed hair casts, also known as pseudonits, which are tubular accretions that encircle hair shafts and can be mistaken for lice nits. Despite the rising awareness of head lice, there had been no additional reports of hair casts in North American literature since 1961. Hair casts are 2 to 7 mm long, firm, shiny, and white, and they may result from the persistence of the hair's inner root sheath. Misdiagnosis of hair casts as lice can lead to significant psychological or physiological consequences. The document included a case of a 7-year-old girl who was misdiagnosed with nits for five years.