Standardized Hair Collections

Identifying AGA and TE

Telogen effluvium (TE) and androgenetic alopecia (AGA) are common, especially among women. There are many ways to differentiate a shedding disorder (TE) from AGA - and some women have both. 

A clinical examination of the scalp, a biopsy and a so called "hair collection" are three methods to evaluate a patient's diagnosis. Exactly which one I use depends on the specific clinical situation. Certainly not everyone with hair loss needs a biopsy and not everyone needs to perform a hair collection.

There are many different ways to perform a hair collection. Rebora studied the use of the 5 day hair collection, where shampooed hairs are trapped on a gauze 5 days after shampooing. The collected hairs are divided into three groups: telogen vellus hairs (less than 3 cm), intermediate hairs (3-5 cm) and long hairs (more than 5 cm). The presence of more than 10 % non broken hairs 3 cm or less is suggestive of the diagnosis of androgenetic alopecia (AGA).

Reference

Distinguishing androgenetic alopecia from chronic telogen effluvium when associated in the same patient: a simple noninvasive method.
Rebora A, et al. Arch Dermatol. 2005.