What is the Difference Between Alopecia Areata and Telogen Effluvium?

Alopecia areata and telogen effluvium are both types of hair loss, but they have different characteristics and causes. Here are the main differences between the two:

Cause: Alopecia areata is an autoimmune condition where the immune system attacks the hair follicles, leading to hair loss. Telogen effluvium, on the other hand, is a temporary hair loss caused by stress or other factors, such as surgery, medications, or hormonal changes.
Onset: Telogen effluvium usually begins suddenly, with a rapid increase in hair loss, while alopecia areata has a more gradual onset.
Hair loss pattern: Alopecia areata typically causes round patches of baldness, while telogen effluvium results in diffuse hair loss all over the scalp.
Microscopic appearance: In alopecia areata, exclamation point hairs may be present, which have a narrow shaft near the scalp and a wider, darker bulb. Telogen effluvium is characterized by increased numbers of shed telogen hairs with variable lengths and diameters.
Duration: Telogen effluvium is a temporary form of hair loss, and shedding usually stops eventually. Alopecia areata can be either permanent or temporary, depending on the severity and response to treatment.
Diagnosis: A detailed history and examination can often differentiate between the two conditions. In cases where the diagnosis is uncertain, a scalp biopsy may be necessary to confirm the cause of hair loss.

In summary, alopecia areata is an autoimmune condition that causes round patches of hair loss, while telogen effluvium is a temporary, stress-related hair loss that occurs diffusely. The onset, hair loss pattern, microscopic appearance, duration, and diagnosis methods are key differences between the two conditions.

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What is the Difference Between Alopecia Areata and Telogen Effluvium?

Comparative Table: Alopecia Areata vs Telogen Effluvium

Here is a table comparing the differences between Alopecia Areata and Telogen Effluvium:

Feature	Alopecia Areata	Telogen Effluvium
Definition	An autoimmune condition characterized by areas of nonscarring hair loss	A temporary hair loss condition caused by a change in the hair growth cycle, usually due to stress or other factors
Hair Loss	Smooth, round patches of hair loss, can also cause total loss of scalp hair (alopecia totalis) or body hair (alopecia universalis)	More diffuse hair loss, tends to be temporary and resolves within 3-6 months
Causes	Immune system attacks hair follicles	Stress, hormonal changes, nutritional deficiencies, medications, and other factors can trigger a change in the hair growth cycle
Diagnosis	Scalp biopsy, presence of exclamation point hairs	History of precipitating event, positive hair pull test
Treatment	No cure, but treatments can help manage symptoms and promote hair regrowth	Hair loss is usually temporary and resolves on its own within 3-6 months
Recurrence	Often, patients with alopecia areata will relapse, resulting in more than one episode in a lifetime	No recurrence, hair loss is temporary and usually does not recur

Please note that this information is for informational purposes only and should not replace consultations with qualified healthcare professionals.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.