Ask the doctors: Sudden, complete loss of hair called alopecia areata
Q: At about 26 years old, my father became sick and lost all of his hair. Not only did he lose hair on his head, he had no eyebrows, eyelashes or beard and even lost the hair on his arms and legs. Do you have any idea what might have caused that?
A: When people think about hair loss, they often think of male pattern baldness (which, contrary to the name, occurs in women as well). It's the most common form of hair loss and is driven primarily by genetics and influenced by hormones. Pattern baldness is marked by gradual thinning hair on the top of the head and a receding hairline. It happens when hair follicles gradually shrink, called miniaturization. The follicles then produce fine, thin, short and weak hair.
The sudden and complete hair loss that you describe is quite different. It is one of several forms of alopecia areata, an autoimmune condition that affects about 2% of all people. Alopecia is the medical term for baldness. It dates back to Hippocrates and comes from the Greek word for fox, “aloplex.” This is a reference to a type of fur loss these animals can suffer. Areata comes from the Latin word “area,” which means vacant or empty space.
Unlike pattern baldness, the hair follicles in alopecia areata aren't affected. The hair loss occurs because an immune system attack disrupts the growth stage of hair production. With a mild form of alopecia areata, hair loss occurs in small, often coin-sized patches on the scalp. It can also occur on other areas of the body.
Alopecia totalis, another form of the condition, causes loss of all or most of the hair on your scalp. Your father experienced sudden hair loss all over the body. This is consistent with the most severe form of this condition, alopecia universalis.
We don't fully understand the mechanisms of alopecia areata yet. Five years ago, researchers at Columbia University in New York did make a leap forward: They compared the genetic profiles of 1,054 people living with the condition with a control group of 3,278 individuals. They identified eight genes that may play a role, including a specific overactive gene, ULBP3.
The ULBP3 gene acted like an alarm bell, calling on the immune system to attack. Additional research has linked some cases of alopecia areata to drugs known as monoclonal antibodies. These are lab-grown proteins that mimic the body's own antibodies.
Currently, there is no cure for alopecia areata. Because the hair follicle itself is not the problem in this condition, existing treatments for pattern baldness don't help. The Food and Drug Administration (FDA) has recently approved several medications for severe forms of the condition. Known as JAK inhibitors, these medications block certain enzymes involved in immune response.
For people living with the condition, the National Alopecia Areata Foundation (NAAF.org) is a great resource for research and support.
• Dr. Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr. Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu.
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