Alopecia Areata
Understanding Alopecia Areata: Causes, Symptoms, and Treatment Options
Alopecia areata is an autoimmune condition that causes sudden, patchy hair loss, affecting the scalp, face, and body. Unlike other forms of hair loss, alopecia areata occurs because the immune system mistakenly attacks hair follicles. This leads to the follicle shrinking and halting hair production. It is generally unpredictable, and the progression and severity can vary greatly from person to person. For some, it may resolve naturally, while for others, it can persist and progress to complete hair loss, such as alopecia totalis, or alopecia universalis. This condition can affect all ages; however, it often begins in late teens or early adults.
What is Alopecia Areata
Alopecia areata is an autoimmune condition where the immune system mistakenly attacks hair follicles. This attack results in inflammation of the follicle, disrupting the natural growth cycle, and eventually leading to hair loss. It’s characterized by sudden and unpredictable hair loss, often as small, round patches on the scalp or body. The condition can range in severity, and range from small, localized patches, to more extensive hair loss like alopecia totalis or alopecia universalis. While it can affect all ages, it’s most common in late teens or young adults. It’s important to realize that alopecia areata is not contagious and is not an indication of poor hygiene.
Causes of Alopecia Areata
Researchers have found that alopecia areata is caused by a combination of interconnected factors. Immune dysfunction, genetic predisposition, hormones, and environmental factors can all contribute to the onset. Understanding the various causes, and how they interact with each other, can help with developing targeted treatment strategies.
Autoimmune Response
Alopecia areata is primarily an autoimmune condition in which the body’s immune system mistakenly identifies hair follicles as foreign. T cells, a type of immune cell, infiltrate the hair follicles, disrupting their normal function causing hair to stop growing. This immune attack will typically target areas in the anagen (growth) phase of the hair cycle. This results in patchy and unpredictable hair loss. The exact trigger for this immune response is not fully known but is believed to be a miscommunication in the body’s immune regulation process.
Genetic Factors
Genetics play a significant role, as those with a family history of autoimmune disorders are more likely to develop alopecia areata. Research has identified specific genes associated with immune regulation, such as those in the HLA (human leukocyte antigen) region. These genes may predispose someone to this condition. Genetic links suggest that alopecia areata is, in part, an inherited condition. Though environmental and immune factors are needed to active its onset.
Environmental Factors
Environmental factors, such as infections, trauma, or exposure to chemicals can act as triggers in those who are genetically predisposed. Viral infections are believed to provoke the immune system and initiate the autoimmune response that targets hair follicles. Both physical and emotional stress can exacerbate immune system dysregulation and accelerate hair loss. Environmental allergens and harsh chemicals can further irritate the scalp, and potentially worsen systems for those genetically predisposed.
Other Autoimmune Conditions
Alopecia areata often occurs alongside other autoimmune disorders, such as thyroid disease, vitiligo, type 1 diabetes, or rheumatoid arthritis. These conditions involve the immune system mistakenly attacking healthy body tissues. This overlap suggests a shared immune system dysfunction causing these conditions. Having one autoimmune disorder can trigger or heighten the severity of others due to the immune systems dysfunction. Those with alopecia areata are more likely to have a family history of immune conditions. This link shows a broader systemic predisposition to autoimmunity conditions.
Hormonal Changes
Hormonal fluctuations can influence the onset or progression of alopecia areata. Hormone altering events can impact the immune systems behavior, potentially worsening autoimmune conditions. Some evidence suggests that stress related hormonal changes can contribute to immune system dysregulation and hair loss.
Symptoms of Alopecia Areata
The main symptom of alopecia areata is the sudden and unpredictable hair loss, in small round patches. While hair loss is the most noticeable symptom, there are other signs that would indicate this condition, such as changes to the nail and skin.
Patchy Hair Loss
- The main symptom of alopecia areata is sudden, round or oval patches of hair loss, most commonly on the scalp. These patches can appear smooth and free of inflammation or scarring. Hair loss can also occur on other parts of the body, such as the beard, eyebrows, eyelashes, or body hair. The size and number of patches can vary widely between individuals.
Hair Shedding
- Increased hair shedding, particularly during brushing or washing, is a common early sign. Large clumps of hair coming out may precede visible bald patches.
Exclamation Mark Hairs
- One of the distinct features of alopecia areata is exclamation mark hairs at the edge of bald patches. They will be short, broken hairs that taper at the base, resembling a question mark (!). They are caused by the hair weakening and breaking near the surface of the scalp.
Widespread Hair Loss
- In some cases, alopecia areata progresses beyond patchy hair loss to more extensive forms, such as alopecia totalis or universalis. Alopecia totalis is the complete loss of scalp hair. Alopecia universalis is more severe and results in the complete loss of hair on the scalp and body.
Nail Changes
- About 10–20% of people with alopecia areata experience nail abnormalities. Common changes include pitting (small dents in the nail surface), ridging, thinning, or white spots. These changes can occur alongside hair loss, or independently.
Scalp Sensations
- Before or during a hair loss episode, there may be an itching, burning, or tingling sensation on the scalp. These are believed to be a result of inflammation of the hair follicles.
Treatment Options for Alopecia Areata
While there is no cure for alopecia areata, a variety of treatments can help manage the condition and promote regrowth. The treatment strategy often depends on the extent and severity of the hair loss. Treatments aim to suppress the immune system response, stimulate hair growth, or both. Although results vary, many people achieve partial or complete regrowth with the appropriate treatment.
Corticosteroids
Corticosteroids are the most commonly used treatment for alopecia areata. They work by suppressing the immune system’s attack on hair follicles. Corticosteroids can be administered in various forms:
- Topical: Creams or ointments applied directly to bald patches.
- Injectable: Steroid injections into the affected areas of the scalp.
- Oral: For more severe cases, systemic corticosteroids may be prescribed, though these are used cautiously due to potential side effects.
Janus Kinase (JAK) Inhibitors
JAK inhibitors, such as tofacitinib and ruxolitinib, are drugs that target the immune pathways involved in alopecia areata. By blocking specific immune signals, JAK inhibitors can reduce inflammation and allow hair follicles to resume normal function. While these are not approved for widespread use, the clinical trails have shown positive results in severe cases.
Topical Immunotherapy
Topical immunotherapy involves applying chemicals, such as diphencyprone (DPCP) or squaric acid dibutylester (SADBE), to the scalp to create a mild allergic reaction. This reaction is used to distract the immune system, preventing it from attacking healthy hair follicles. It is often used for extensive or recurrent alopecia areata and may take several months to show results.
Minoxidil (Rogaine)
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Minoxidil is a topical treatment that is commonly used for androgenetic alopecia. In the case of alopecia areata, minoxidil helps by stimulating hair follicles to promote regrowth. It is often combined with other treatments, like corticosteroids, to enhance effectiveness.
Platelet-Rich Plasma (PRP) Therapy
PRP therapy involves extracting a small amount of blood, processing it to concentrate platelets, and injecting it into the scalp. Platelets contain growth factors that can help stimulate hair regrowth and repair damaged follicles.
Anthralin (Dritho-Scalp)
Anthralin is a topical medication originally used for psoriasis that can also treat alopecia areata. It works by modulating the immune response in the skin and creating mild irritation to stimulate hair regrowth. Anthralin is applied to the affected areas for a short period and then washed off.
Low-Level Laser Therapy (LLLT)
LLLT uses devices that emit low-intensity laser light to stimulate hair follicles and improve circulation in the scalp. Though it is most common for androgenetic alopecia, there have been positive results with alopecia areata. LLLT is non-invasive and can be done at home with FDA-approved devices.
Hair Transplant Surgery
In cases of severe and permanent hair loss due to alopecia areata, hair transplant surgery may be an option. This procedure involves removing healthy hair follicles from one area of the scalp (often the back or sides) and transplanting them to areas of hair loss. While this is not the first treatment to consider, it can offer a permanent solution. It may be considered by those who have not responded positively to other treatments.
Frequently Asked Questions (FAQ)
It is an autoimmune condition where the body’s immune system mistakenly attacks hair follicles, leading to hair loss. The hair loss typically occurs in small, round patches on the scalp but can also affect other areas of the body, such as the beard, eyebrows, and eyelashes.
The exact cause is not fully understood, but it is believed to result from a combination of genetic predisposition and environmental triggers, such as stress, infections, or trauma. People with a family history of autoimmune disorders may be at a higher risk.
There is currently no permanent cure; however, various treatments, such as corticosteroids, topical immunotherapy, and minoxidil, can help manage the condition and promote hair regrowth. In many cases, hair regrows naturally over time, though recurrence is common.
No, it is not contagious. It is an autoimmune disorder and cannot be spread through physical contact, sharing personal items, or any other means.
It is typically diagnosed through a physical examination of the hair and scalp by a dermatologist. In some cases, a scalp biopsy or blood tests may be performed to rule out other causes of hair loss and confirm the diagnosis.
Conclusion
Alopecia is a complex autoimmune condition resulting in unpredictable hair loss. It can have significant impact on physical appearance and emotional well-being. While the exact causes are unclear, research has provided insight on its genetic, immunological, and environmental factors. While there is no cure, there are a variety of treatment options to help manage the condition and regrow hair.
Want to Learn More?
View the latest scientific paper on Alopecia Areata from the National Library of Medicine.
