hair loss classification
There are numerous ways to classify hair loss. One useful way has been to classify hair loss by whether the loss is localized (small area) and patchy or whether it affects large areas or the whole scalp (diffuse). Other medical classifications for hair loss include scarring versus non-scarring hair loss and are beyond the scope of this article.
Patchy hair loss
Some conditions produce small areas of hair loss, while others affect large areas of the scalp. Common causes of patchy hair loss are
* alopecia areata (small circular or coin size patches of scalp baldness that usually grow back within months),
* traction alopecia (thinning from tight braids or ponytails),
* trichotillomania (the habit of twisting or pulling hair out),
* and tinea capitis (fungal infection).
What is alopecia areata?
A common condition, alopecia areata usually starts as a single quarter-sized circle of perfectly smooth baldness. Alopecia patches usually regrow in three to six months without treatment. Sometimes, hair grows back in white. In another variant, alopecia can produce two or three bald patches. When these grow back, they may be replaced by others. The most extensive form is called alopecia totalis, in which the entire scalp goes bald. It’s important to emphasize that patients who have localized hair loss generally don’t go on to lose hair all over the scalp. Alopecia can affect hair on other parts of the body, too — for example, the beard or eyebrow.
Alopecia areata is generally considered an autoimmune condition, in which the body attacks itself (in this case its own hair follicles). Most alopecia patients, however, do not have systemic problems and need no medical tests. While alopecia areata has frequently been blamed on “stress,” in fact, it may be the other way around; that is, having alopecia may cause stress.
Treatments for alopecia areata include injecting small amounts of steroids like triamcinolone into affected patches to stimulate hair growth. Although localized injections may not be practical for large areas, often this is a very effective treatment in helping the hairs return sooner. Other treatments such as oral steroids, immunosuppressives, or ultraviolet light therapy are available for more widespread or severe cases but may be impractical for some because of potential side effects or risks. In most mild cases, patients can easily cover up or comb over the affected areas. In more severe and chronic cases, some patients wear hairpieces; nowadays, some men shave their whole scalp now that this look has become fashionable.
What is traction alopecia?
This is a small or localized hair loss area caused by repetitive or persistent pulling or force on hair roots. Tight braids and ponytails can pull hard enough on hairs to make them fall out. If this happens, it’s best to choose hairstyles that put less pressure on hair roots. The sooner this is done the better to avoid permanent damage.
What is trichotillomania?
This refers to the habit of someone voluntarily pulling at their own hairs or twisting them, sometimes without realizing it. The scalp and eyelashes are often affected. Unlike alopecia areata patches, which are perfectly smooth, hair patches in trichotillomania show broken-off hairs. Treatment is often entirely behavioral: You have to notice that you’re doing it and then consciously stop. Severe or resistant cases may require stress counseling with a therapist or psychologist or medical treatment with a psychiatrist. Several antidepressant or anxiety medications have been shown to potentially help with this condition.
What is tinea capitis?
Tinea is the medical word for fungal infection, and capitis means head. Tinea capitis is fungal infection of the scalp that for the most part affects school-age children. Tinea capitis is more common in black African or African-American scalps. This condition is rare in healthy adults. Bald spots usually show broken-off hairs. Oral antifungals are needed to penetrate the hair roots and cure the infection after which hair grows back. It is contagious from sharing hats or combs and brushes.
What is generalized (diffuse) hair loss?
This is an overall hair thinning without specific bald spots or patterns. While this type of hair loss may not be noticeable to others, often the individual will feel their hair is not as thick or full as it previously was. Common conditions in this category are
* telogen effluvium (rapid shedding after childbirth, fever, or sudden weight loss);
* androgenetic or androgenic hair loss (“male-pattern baldness,” “female-pattern baldness”).