Alopecia

Definition

Definition of Alopecia
Alopecia means loss of hair from the head or body. Alopecia can mean baldness, a term generally reserved for pattern alopecia or androgenic alopecia. Compulsive pulling of hair (trichotillomania) can also produce hair loss. Hairstyling routines such as tight ponytails or braids may induce Traction alopecia. Both hair relaxer solutions, and hot hair irons can also induce hair loss. In some cases, alopecia is due to underlying medical conditions, such as iron deficiency.

Symptoms

Symptoms of Alopecia
When examining the scalp, the distribution of hair loss, presence and characteristics of skin lesions, and the presence of scarring should be noted. Part widths should be measured. All abnormalities should be noted. In male-pattern hair loss, loss and thinning begin at the temples and either thins out or falls out. Female-pattern hair loss occurs when hair thinning occurs at the frontal and parietal.

Causes

Causes of Alopecia
Various kind of Alopecia causes:

1. Alopecia mucinosa
2. Androgenic alopecia
3. Dissecting Cellulitis
4. Fungal Infections (such as tinea capitis)
5. Hair Treatments (chemicals in relaxers, hair straighteners)
6. Hereditary Disorder
7. Hormonal Changes
8. Hyperthyroidism and Hypothyroidism
9. Hypervitaminosis A
10. Iron deficiency
11. Lupus Erythematosus
12. Medications (side effects from drugs, such as chemotherapy)
13. Pseudopelade of Brocq
14. Radiation therapy
15. Scalp infection
16. Secondary syphilis
17. Telogen effluvium
18. Traction alopecia
19. Trichotillomania
20. Tufted folliculitis

Diagnosis

Diagnosis of Alopecia
Evaluation for causative disorders should be done based on clinical symptoms. Because they are not usually associated with an increased loss rate, male-pattern and female-pattern hair loss don’t generally require testing. If hair loss occurs in a young man with no family history, the physician should question the patient on drug and illicit drug use.

1. The pull test: this test helps to evaluate diffuse scalp hair loss. Gentle traction is exerted on a group of hair (about 40–60) on three different areas of the scalp. The number of extracted hairs is counted and examined under a microscope. Normally, <3 hairs per area should come out with each pull. If >10 hairs are obtained, the pull test is considered positive.
2. The pluck test: In this test, the individual pulls hair out “by the roots.” The root of the plucked hair is examined under a microscope to determine the phase of growth and used to diagnose a defect of telogen, anagen, or systemic disease. Telogen hairs are hairs that have tiny bulbs without sheaths at their roots. Telogen effluvium shows an increased percentage of hairs upon examination. Anagen hairs are hairs that have sheaths attached to their roots. Anagen effluvium shows a decrease in telogen-phase hairs and an increased number of broken hairs.
3. Scalp biopsy: This test is done when alopecia is present, but the diagnosis is unsure. The biopsy allows for differing between scarring and nonscarring forms. Hair samples are taken from areas of inflammation, usually around the border of the bald patch.
4. Daily Hair Counts: This is normally done when the pull test is negative. It is done by counting the number of hairs lost. The hair that should be counted are the hairs from the first morning combing or during washing. The hair is collected in a clear plastic bag for 14 days. The strands are recorded. If the hair count is >100/day, it is considered abnormal except after shampooing, where hair counts will be up to 250 and be normal.
5. Trichoscopy: Trichoscopy is a non-invasive method of examining hair and scalp. The test may be performed with the use of a handheld dermoscope or a video dermoscope. It allows differential diagnosis of hair loss in most cases.

Pathophysiology

Pathophysiology of Alopecia
Hair follicle growth occurs in cycles. Each cycle consists of a long growing phase (anagen), a short transitional phase (catagen) and a short resting phase (telogen). At the end of the resting phase, the hair falls out (exogen) and a new hair starts growing in the follicle beginning the cycle again.

Treatment

Treatment of Alopecia

1. Minoxidil (Rogaine): This is a non-prescription medication approved for androgenetic alopecia and alopecia areata. Minoxidil comes in a liquid or foam that is rubbed into the scalp twice a day. This is the most effective method to treat male-pattern and female-pattern hair loss. However, only 30–40% of patients experience hair growth. Minoxidil is not effective for other causes of hair loss except alopecia areata. Hair regrowth can take 8 to 12 months. Treatment is continued indefinitely because if the treatment is stopped, hair loss resumes again. Most frequent side effects are mild scalp irritation, allergic contact dermatitis, and increased facial hair.
2. Finasteride (Propecia): Is used in male-pattern hair loss in a pill form taken on a daily basis. Finasteride is not indicated for women and is not recommended in pregnant women. Treatment is effective within 6 to 8 months of treatment. Side effects include decreased libido, erectile dysfunction, ejaculatory dysfunction, gynecomastia, and myopathy. Treatment should be continued as long as positive results occur. Once treatment is stopped, hair loss resumes again.
3. Corticosteroids: Injections of cortisone into the scalp can be used to treat alopecia areata. This type of treatment is repeated on a monthly basis. Physician may prescribe oral pills for extensive hair loss due to alopecia areata. Results may take up to a month to be seen.
4. Anthralin (Dritho-Scalp): Available as a cream or ointment that is applied to the scalp and washed off daily. More commonly is used to treat psoriasis. Results may take up to 12 weeks to be seen.
5. Hormonal Modulators: Oral contraceptives or antiandrogens like spironolactone and flutamide can be used for female-pattern hair loss associated with hyperandrogenemia.
6. Surgical Options: Treatment options such as follicle transplant, scalp flaps, and alopecia reduction are available. These procedures are generally chosen by those who are self-conscious about their hair loss. These options are expensive and painful. There is a risk of infection and scarring. Once surgery has occurred, it takes 6 to 8 months before the quality of new hair can be assessed.
7. Wigs: As an alternative to medical and surgical treatment, some patients wear a wig or hairpiece. They can be used permanently or temporarily to cover the hair loss. Quality, and natural looking wigs and hairpieces are available.