ANAGEN EFFLUVIUM

 

 

 

AE is a result of a disturbance of hair follicle matrix cells. The anagen phase is interrupted and the hair falls out 7–14 days after the initiating event without entering catagen or telogen. Two different types of AE can be distinguished: Dystrophic AE and Immediate anagen release. Dystrophic AE can be caused by chemotherapy, radiation, toxins or alopecia areata. Microscopic investigation of the hair bulbs, obtained from a hair pull test or trichogram, usually shows a tapered tip with the weakened hair shaft broken shortly above the bulb (“dystrophic hair”).

Drugs used in chemotherapy quickly produce severe hair loss and even total baldness. A rapid onset undoubtedly indicates an immediate release from anagen hair. Immediate anagen hair release is characterized by an easy release of anagen hairs after gentle pulling. The anagen hair has a broom-shaped, pigmented bulb. Therapeutic agents that can cause immediate anagen hair shedding include vincristine, vinblastine, methotrexate, doxorubicin, and fluorouracil.

Once the initiating trigger is removed, the hair usually regrows after around 120 days. Cases of incomplete recovery following multiagent chemotherapy have been reported. Patients should be advised about scalp prostheses and other forms of head covering.

Features differentiating between telogen effluvium and anagen effluvium