Noncicatricial alopecia refers to a type of hair loss that is not caused by scarring or destruction of the hair follicle. Unlike cicatricial alopecia, which is characterized by permanent hair loss due to damage to the hair follicles, noncicatricial alopecia results in temporary or reversible hair loss.
There are several different types of noncicatricial alopecia, including androgenetic alopecia, telogen effluvium, alopecia areata, and traction alopecia.
Androgenetic alopecia, also known as male or female pattern baldness, is the most common form of noncicatricial alopecia. It is caused by a combination of genetics and hormonal changes, and is characterized by a gradual thinning of the hair on the scalp, particularly at the crown and temples. Men with androgenetic alopecia often experience a receding hairline and balding on the top of the head, while women tend to experience thinning all over the scalp.
Telogen effluvium is a type of hair loss that is characterized by a sudden shedding of hair, usually following a major life stressor, such as pregnancy, surgery, or severe illness. During telogen effluvium, the hair growth cycle is disrupted, causing a large number of hair follicles to enter the telogen (resting) phase. As a result, the hair falls out in large clumps, often leading to noticeable thinning on the scalp.
Alopecia areata is an autoimmune disorder that causes hair loss in patches on the scalp and other areas of the body. The exact cause of alopecia areata is not known, but it is believed to be related to an overactive immune system that attacks the hair follicles. The hair loss associated with alopecia areata is often sudden and can be accompanied by itching and burning on the affected areas.
Traction alopecia is a type of hair loss that is caused by physical stress on the hair, such as tight braids, weaves, or ponytails. This stress can cause the hair follicles to become inflamed, leading to hair breakage and eventual hair loss. Traction alopecia is most common in people with tightly coiled or curly hair, but it can occur in anyone who wears their hair in tight styles for extended periods of time.
The following is a detailed explanation of the main causes of non-cicatricial alopecia.
- Androgenetic Alopecia: This is the most common form of non-cicatricial alopecia and is also known as male or female pattern baldness. It is caused by a combination of genetics and hormonal changes. Men with androgenetic alopecia typically develop a receding hairline and baldness on the crown, while women tend to experience thinning of the hair on the top of the scalp. This type of hair loss is caused by the conversion of testosterone to dihydrotestosterone (DHT) by the enzyme 5-alpha-reductase. DHT causes the hair follicles to shrink, leading to a reduction in hair growth.
- Telogen Effluvium: This type of hair loss is caused by a sudden or dramatic change in the hair growth cycle. Normally, about 10% of the hair on the scalp is in the resting phase (telogen) at any given time. In telogen effluvium, an increased number of hair follicles enter the telogen phase and fall out, resulting in hair loss. Common causes of telogen effluvium include stress, major illness, surgery, childbirth, and sudden weight loss.
- Alopecia Areata: This is an autoimmune condition in which the body’s immune system attacks the hair follicles, causing hair loss. The hair loss is often sudden and patchy and can occur on the scalp, face, and other areas of the body. The exact cause of alopecia areata is unknown, but it is believed to be a combination of genetic and environmental factors.
- Traction Alopecia: This type of hair loss is caused by constant pulling or tension on the hair, such as from tight braids, cornrows, or hair extensions. The constant pulling causes damage to the hair follicles, leading to hair loss. Traction alopecia is more common in people with curly or kinky hair, as they are more likely to have their hair styled in tight braids or cornrows.
- Scarring Alopecia: Scarring alopecia is a type of hair loss that is caused by scarring on the scalp. This can be the result of various conditions, including lupus, scleroderma, and folliculitis decalvans. Scarring alopecia can also be caused by certain hair treatments, such as hot oil treatments or chemical relaxers. In scarring alopecia, the hair follicles are destroyed and replaced by scar tissue, resulting in permanent hair loss.
- Nutritional Deficiencies: A lack of certain nutrients, such as iron, biotin, and vitamin D, can cause hair loss. Iron deficiency anemia is a common cause of hair loss, as iron is necessary for the production of hemoglobin, which carries oxygen to the hair follicles. Biotin is a B-vitamin that is essential for healthy hair, skin, and nails, while vitamin D is important for the growth and maintenance of hair follicles.
- Hormonal Imbalances: Hormonal imbalances, such as those that occur during menopause, pregnancy, and thyroid disorders, can cause hair loss.
The following are the main symptoms of noncicatricial alopecia:
- Gradual hair thinning: This is the most common symptom of noncicatricial alopecia. It often begins at the crown of the head and spreads gradually to other areas. The hair may become finer and less dense, and eventually, the scalp may become visible.
- Patchy hair loss: In some cases, noncicatricial alopecia can cause patchy hair loss, with bald spots appearing on the scalp. These patches may be round or oval in shape and may be accompanied by itching and scaling.
- Receding hairline: Another common symptom of noncicatricial alopecia is a receding hairline. This occurs when the hairline begins to recede from the forehead, creating a “M” shape.
- Total hair loss: In severe cases of noncicatricial alopecia, total hair loss may occur, with the scalp becoming completely bald.
- Nail changes: In some cases, noncicatricial alopecia can also cause changes to the nails, such as ridges, pits, and brittle nails.
- Scalp itching and burning: Some people with noncicatricial alopecia may experience itching and burning of the scalp, which can be quite distressing.
- Scalp redness and scaling: In some cases, noncicatricial alopecia can cause redness and scaling of the scalp, which can be accompanied by a flaky, itchy scalp.
Here are several different types of noncicatricial alopecia, each with its own set of diagnostic tests. In this article, we’ll discuss some of the main diagnostic tests for noncicatricial alopecia.
- Trichoscopy: Trichoscopy is a non-invasive diagnostic tool that uses a specialized dermatoscope to examine the hair and scalp. During trichoscopy, a dermatologist will look for specific patterns and structures within the hair and scalp that can help diagnose noncicatricial alopecia. This may include looking for miniaturized hairs, broken hairs, and increased scaliness of the scalp.
- Hair Pull Test: The hair pull test is a simple diagnostic tool that involves pulling a small number of hairs from the scalp to determine the rate of hair shedding. During the hair pull test, a dermatologist will gently pull a small group of hairs from the scalp and count the number of hairs that come out. A normal hair pull test result is fewer than three hairs.
- Scalp Biopsy: In some cases, a scalp biopsy may be necessary to diagnose noncicatricial alopecia. During a scalp biopsy, a small sample of scalp tissue is removed and examined under a microscope. This allows a dermatologist to identify any underlying conditions that may be causing the hair loss.
- Blood Tests: Blood tests can help to diagnose certain types of noncicatricial alopecia. For example, a thyroid panel may be performed to determine if the hair loss is caused by an underlying thyroid disorder. Other blood tests that may be performed include tests for iron levels, androgen levels, and autoimmune markers.
- Phototrichogram: Phototrichogram is a specialized diagnostic tool that uses a specialized camera to examine the hair and scalp. During phototrichogram, a dermatologist will take multiple photographs of the hair and scalp in different lighting conditions to identify any patterns or structures that may be indicative of noncicatricial alopecia.
- Scalp Examination: A scalp examination is a simple diagnostic tool that involves examining the scalp for any signs of hair loss or thinning. During a scalp examination, a dermatologist will look for any signs of hair miniaturization, broken hairs, and increased scaliness of the scalp.
- Light Microscopy: Light microscopy is a diagnostic tool that uses a microscope to examine hair and scalp samples. During light microscopy, a dermatologist will examine hair samples under a microscope to look for any signs of hair damage or hair shaft abnormalities that may be indicative of noncicatricial alopecia.
- Ferritin Level Test: Ferritin is a protein that stores iron in the body. A low ferritin level can indicate an iron deficiency, which can cause hair loss. A ferritin level test can help determine if an iron deficiency is the cause of the hair loss.
- Hormonal Tests: Hormonal tests can help diagnose certain types of noncicatricial alopecia that are caused by hormonal imbalances. For example, a test for testosterone levels may be performed to determine if the hair loss is caused by male pattern baldness.
- Scalp MRI or CT Scan: In some cases, a scalp MRI or CT scan may be necessary to diagnose noncicatricial alopecia.
The main treatments for noncicatricial alopecia include medical therapies, topical treatments, and hair transplantation.
- Minoxidil: Minoxidil is a topical medication that is applied directly to the scalp. It works by increasing blood flow to the hair follicles, which can help to stimulate hair growth. Minoxidil is commonly used to treat androgenetic alopecia, and it is available over-the-counter in a 2% solution or by prescription in a 5% solution.
- Finasteride: Finasteride is a oral medication that is used to treat androgenetic alopecia. It works by blocking the conversion of testosterone to dihydrotestosterone (DHT), which is a hormone that can cause hair loss. Finasteride is taken orally once daily, and it is available by prescription only.
- Corticosteroids: Corticosteroids are medications that can be taken orally or applied topically to the scalp. They work by reducing inflammation and suppressing the immune system, which can help to slow down or prevent hair loss in conditions such as alopecia areata. Corticosteroids can be used in a variety of forms, including pills, creams, gels, and injections.
- Topical Immunotherapy: Topical immunotherapy is a treatment that involves applying a chemical irritant to the scalp. This irritant can help to stimulate an immune response, which can help to slow down or prevent hair loss in conditions such as alopecia areata. Topical immunotherapy is typically used in conjunction with other treatments, such as corticosteroids.
- Scalp Microneedling: Scalp microneedling is a procedure that involves using a special device to create tiny pinpricks in the scalp. This can help to stimulate blood flow to the hair follicles and promote hair growth. Scalp microneedling can be done in a dermatologist’s office or at home, and it is typically performed in conjunction with other treatments, such as minoxidil.
- Platelet-rich Plasma (PRP) Therapy: PRP therapy is a treatment that involves using a patient’s own blood to stimulate hair growth. Blood is drawn from the patient and processed to concentrate the platelets, which are then injected back into the scalp. Platelets contain growth factors that can help to stimulate hair growth and improve the overall health of the hair follicles.
- Low-Level Laser Therapy (LLLT): LLLT is a treatment that involves using a low-level laser to stimulate hair growth. The laser light can penetrate the scalp and stimulate the hair follicles, which can help to improve hair growth and prevent hair loss. LLLT is typically performed in a dermatologist’s office or at home using a special device, and it is typically performed in conjunction with other treatments, such as minoxidil.
Hair transplantation is a surgical procedure that involves removing hair follicles from one area of the scalp and transplanting them to another area. This can be used to restore hair growth in areas that are affected by hair loss. There are two main types of hair transplantation