TELOGEN EFFLUVIUM AND
ANAGEN EFFLUVIUM
Telogen effluvium and
anagen effluvium are commonly encountered forms of nonscarring hair loss.
Clinical Findings: Telogen effluvium is a form of nonscarring alopecia that can result in dramatic thinning of the scalp hair but rarely causes total hair loss. It has been found to be induced by a number of stressors that cause the anagen hairs to abruptly turn into telogen hairs. This results in an abnormal number of hairs in the telogen phase and an increase in hair shedding. The hair loss can be profound and disconcerting to the patient. Causes include childbirth, major illness or stress, surgery, and medications. The hair loss is less rapid than in anagen effluvium.
Anagen
effluvium is a specific form of alopecia that is typically induced by
chemotherapeutic agents. Alkylating agents such as busulfan and cisplatin and
the antitumor antibiotics (bleomycin and actinomycin D) are frequently
responsible. Other agents have been implicated, including the antimetabolites,
topoisomerase inhibitors, and vinca alkaloids. The anagen phase hair is
particularly sensitive to these chemotherapy agents, which inhibit
proliferation of rapidly dividing cells. This form of hair loss is easier to
diagnosis, because a history of taking one of the implicated chemotherapeutic
agents is critical in making the diagnosis.
Histology: Scalp biopsies are one of the best ways of confirming
the diagnosis. The standard procedure is to obtain a 4-mm punch biopsy from the
affected region. Instead of the routine vertical sectioning, horizontal
sectioning is performed. Punch biopsies have been standarized to 4 mm. The
presence of scarring, the form of inflammation, and the ratio of anagen to telogen
hairs are evaluated. In telogen effluvium, a normal number of hairs are present
without evidence of miniaturization. The ratio of telogen to anagen hairs is
increased from the normal 5 to 10 telogen hairs per 100 anagen hairs to more
than 20 per 100. Biopsies of anagen effluvium show a normal ratio of anagen to
telogen hairs, but the anagen hairs exhibit some evidence of abnormality,
either broken shafts or apoptosis of the hair.
Pathogenesis: Telogen effluvium can almost always be traced to a recent
illness, surgery, iron deficiency, child bearing, or other major stressor in
the patient’s life. Many medications have been reported to induce telogen
effluvium, and the clinician should evaluate all medications taken. Dietary
habits, especially crash dieting and anorexia nervosa, may lead to telogen
effluvium. The hair follicles are not scarred and eventually grow back after
the stressors have been resolved. Because the beginning of hair loss may be
delayed after the stressful event, by 3 to 4 months on average, the patient may
not realize the relationship.
Treatment: The treatment of telogen effluvium consists of
determining the etiology and educating the patient. It is important to rule out
an underlying disorder (e.g., iron deficiency, hypothyroidism) that may be
triggering the hair loss. Once this has been accomplished, patients need to be
educated and reassured that telogen effluvium almost always resolves within 6
to 8 months, and they may expect full regrowth. Supple-mental vitamins and
topical minoxidil have not been vigorously tested as therapies for telogen
effluvium, and their use cannot be scientifically advocated. Referral to a
psychological counselor may be appropriate in situations such as eating
disorders.
Anagen effluvium is related to the use of chemotherapeutic agents to treat systemic cancer. The therapy should not be stopped because of this side effect. After therapy has been completed, most patients regrow their hair. Patients have reported many changes in the color, texture, and curling of their newly grown hair. These changes have not been fully explained. Topical minoxidil may shorten the duration of anagen effluvium, but its prophylactic use has not been helpful in preventing it. More studies are needed to confirm these findings. At this point, education and reassurance are the most important therapeutic considerations. Most patients will regrow their hair, and for the few that do not, other options exist. The use of hair pieces has been expanded for many medically related forms of alopecia.
