hair pluck test

Indications: - distinguishing anagen effluvium from telogen effluvium Procedure: - hairs are obtained by grasping about 50 with a rubber-tipped forceps, rotating one turn & pulling upwards, plucking the hairs - the hair is cut about 1 cm from the root, placed on a wet-mount microscope slide & viewed at 10X - DACA (4-dimethylaminocinnamaldehye) reacts with an internal root sheath amino acid allowing differentiation of anagen from telogen hairs - telogen hairs have small avoid bulbs that do not stain with DACA because they lack a sheath, whereas anagen hairs have larger bulbs surrounded by a brightly red-stained sheath Interpretation: - normally only 10-15% of hairs are telogen hairs - in telogen effluvium, 30-60% of hairs of telogen hairs - in anagen effluvium, 100% are telogen hairs

References

Saunders Manual of Medical Practice, Rakel (ed), WB Saunders, Philadelphia, 1996, pg 918