Drs Weedon and Strutton note that ''perpetuation of this concept (telogen effluvium) obscures the important role of catagen.'' I find this observation to be a rather curious misreading of my clinically oriented article.1 The concept of catagen is unequivocally useless to the clinician, because there are no detectable signs for this phase of the hair cycle.
By contrast, however, the morphologic recognition of so-called catagen is important for the histologic diagnosis of some alopecias, and I have purposefully combined catagen and telogen in my discussion of the histology of telogen effluvium (catagen-telogen) to specifically indicate a histologic continuum of regressive changes that ends with formation of the club hair. Of these changes, the most important is volumetric reduction of the terminal follicle by the process of apoptosis, a point noted in my discussion of the transverse microscopic anatomy of the human scalp in 19842 as then attributed to Weedon and Strutton's
Headington JT. Telogen Effluvium-Reply. Arch Dermatol. 1994;130(2):254. doi:10.1001/archderm.1994.01690020124023
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