Pediculosis
 June 1980   
in “
 International Journal of Dermatology 
”
 
    alopecia  scalp biopsy  telogen effluvium  telogen hairs  X-ray alopecia  thallium alopecia  matrix collapse  hormonal disturbances  thyroid deficiency  pituitary deficiency  systemic lupus erythematosus  trichotillomania  trichomalacia  catagen induction  carcinomatous alopecia  Jadassohn's nevus sebaceus  organoid nevus  hair shaft deformities  hamartomatous malformation  elastic fiber staining  hair loss  scalp biopsy  hair shedding  hair roots  hair pulling  hair deformities  hair follicle malformation   
    
   TLDR  Scalp biopsies are important for diagnosing hair loss conditions.   
  The document discusses various causes and characteristics of alopecia, emphasizing the importance of scalp biopsies in diagnosing hair loss conditions. Telogen effluvium is characterized by an increased number of falling hairs and can be estimated by counting the number of telogen hairs in a scalp biopsy. X-ray and thallium alopecia result in sudden hair loss within three weeks due to matrix collapse. Hormonal disturbances like thyroid and pituitary deficiencies, as well as systemic lupus erythematosus, can decrease hair growth. Trichotillomania, described as trichomalacia, involves the patient pulling their hair, leading to hair shaft deformities and catagen induction. Carcinomatous alopecia may occur without forming a tumor, due to infiltration from carcinoma. Jadassohn's nevus sebaceus is an organoid nevus with underdeveloped hair roots, which may lead to tumors later in life. The document concludes with a case of a girl with hamartomatous malformation of every hair follicle, highlighting the need for more scalp biopsies and elastic fiber staining in alopecia cases.
    
   
   
   
   
  