Miscellaneous Disorders

Abstract

The miscellaneous disorders by definition have no central finding but do include many diseases in one category, namely, hair disorders. Thus, trichorrhexis nodosa, trichotillomania, and loose anagen syndrome are in this group. Telogen effluvium, alopecia areata, Netherton syndrome, Menkes kinky hair syndrome, and tinea capitis are all diseases that involve the hair but have relationships with conditions in other sections of this book. These entities could easily have been included here.

Trichorrhexis nodosa, with the keyword “broomsticks,” has nodes in the hair shaft that on microscopy have the appearance of two brooms pushed together. This node breaks easily, leaving one broom intact. In our clinic, this phenomenon occurs frequently in young to middle-aged black women; the nodes generally reside 2–4 cm from the scalp, so that on breakage the hair involved ends up at that length. In white patients, nodes may be situated more distally, where the node undergoes fracture, and the hair has the appearance of a “split end.”