Diffuse alopecia

What is it diffuse alopecia?

Alopecia is the medical term for hair loss. Alopecia is diffuse if it affects the scalp in general. distribution. This is in contrast to located or focal alopecia, which is characterized by patchy hair loss.

Who gets diffuse alopecia?

Diffuse alopecia is common and affects up to 50% of men and women. Although it can affect both sexes at any age, women occur more frequently than men. [1,2].

the hair cycle

Hair follicles Cycle through the growth and rest phases.

• the anagen The (growth) phase lasts from two to six years.
• This is followed by the short catagen (transitional) phase, which lasts four to six weeks.
• the telogen (resting) phase lasts two to three months and ends with the release of the hair from the follicle [3,4].

How is diffuse alopecia classified?

Diffuse alopecia can be classified into conditions that cause excessive hair shedding and conditions that cause thinning hair [1].

Excessive hair shedding

Abnormal hair loss (or shedding) can occur during the telogen or anagen phase of the hair cycle.

Telogen effluvium

Telogen effluvium is the most common cause of diffuse hair loss. [3,5]. A triggering event causes a greater number of anagen hairs to prematurely enter the catagen and then telogen phase. Excessive shedding of telogen hairs occurs a few months after the triggering event. [3].

Patients may notice clumps of hair falling out on the brush or while bathing [6]. Up to 30–50% of scalp hair can be lost [1]. Excess hair loss can cause diffuse thinning or bitemporal recession [3].

Several triggers have been implicated in telogen effluvium; These include:

• Severe or high illness fever
• Birth
• Lack of iron
• Thyroid disease (hyperthyroidism or hypothyroidism)
• Kidney or liver disease

• Malnutrition or strict diets

• Infections such as syphilis.
• Many types of medications (see Drug-Induced Alopecia)
• Emotional stress
• Systemic lupus erythematosus [3,6].

Anagen Effluvium

Anagen effluvium occurs when the anagen phase is disrupted, causing premature termination of hair growth and abrupt hair loss.

Anagen effluvium is most commonly due to chemotherapy (see drug-induced alopecia) and usually begins one to two weeks after treatment is started. It can cause 80 to 90% loss of body hair, including eyebrows and eyelashes. [1,2]. It can also be caused by poisoning with thallium, colchicine, or selenium. [7].

Anagen effluvium can also be caused by alopecia areata [2]. Alopecia areata is a autoimmune condition in those with genetic predisposition and typically presents with bald patches (focal alopecia) [2,5]. Confluent or extended Alopecia areata presents with diffuse hair loss, sometimes resulting in complete baldness of the scalp (alopecia totalis) or total loss of body hair (alopecia universalis) [1,2,5].

hair thinning

Diffuse gradual thinning of hair is due to male or female pattern hair loss.

hair loss pattern

Diffuse hair thinning due to hair loss is a gradual process [1,8].

Male pattern hair loss is caused by a genetic predisposition which affects the sensitivity of hair follicles to circulation androgens; For this reason, it is sometimes called androgenetic alopecia [1,4]. The characteristic pattern is a bitemporal recession and baldness in the vertex and frontal regions.

Female-pattern hair loss has a strong genetic component, but the role of androgens is unclear [8]. The pattern thins over the top of the scalp with a widening of the middle line part [1,4].

Pattern hair loss in women occurs earlier and more severely in polycystic ovary. syndrome, with a virilizing tumor, or exposed to a exogenous androgynous how testosterone.

What are the complications of diffuse alopecia?

Hair loss has minimal harmful physical effects; However, it can be psychologically damaging and negatively impact quality of life, as hair is linked to one's identity (see Psychological Effects of Hair Loss). Psychiatric Disorders, such as anxiety and depression, are more common in people with alopecia than in people without [6,9].

How is diffuse alopecia diagnosed?

Diffuse alopecia is usually diagnosed clinically, with a detailed history and scalp examination. Additional tests may be used to confirm the diagnosis. [6].

History and exam

History can identify triggers or genetic susceptibility [6].

• Examination of the scalp should evaluate the degree and pattern of hair loss. The scalp should also be examined for inflammation, redness and climbing [2].
• The length, diameter and breakage of the hair shaft should be evaluated. [2].
• Examination of the scalp with a dermatoscope (trichoscopy) may provide more information (see Dermatoscopy) [4].
• Nail changes may be seen with diffuse alopecia (see Nail Disorders).
  • Beau's lines are a groove in the nail that coincides with the moment hair growth stops.
  • A bites It is associated with alopecia areata [6].

Blood test

Laboratory examination should be performed to identify treatable causes. This may include:

• Complete blood count and ferritin Exclude anemia
• Thyroid function tests to exclude thyroid disease
• Serum zinc level to exclude zinc deficiency
• Renal and liver function tests to exclude kidney or liver disease
• Antinuclear antibodies if features suggest systemic lupus erythematosus
• Hormonal evaluation (free androgen index, sex hormone-binding globulin, prolactin) in women with clinical signs of hyperandrogenism [2–4,8].

Hair pull test

The hair stretch test involves grabbing 40-60 up close grouped hairs and applying gentle traction. If more than 10% of hairs are easily pulled out, the test is positive. [3].

• The hair pull test is positive in telogen effluvium, anagen effluvium and diffuse alopecia areata [6].
• The hair pull test is negative (away from hair loss areas) in male and female pattern hair loss [1].

Trichogram

For a trichogram, 20 to 50 hairs are plucked and then analyzed under a microscope to estimate the percentages of anagen and telogen hairs.

• A normal result is > 80% of anagen hairs and <20% de pelos telógenos [4].

• Telogen effluvium is characterized by a 25% of telogen hairs [3].

• Hairs with exclamation points (in which the hair shaft is narrower towards the scalp, mimicking an exclamation point) are typical of alopecia areata [6].

Scalp biopsy

An optimal scalp skin biopsy involves two four-millimeter punches. biopsies from the vertex of the scalp [5].

• An increase in the number of telogen follicles (>15-25%) without inflammation is observed in telogen effluvium [3,5].
• A dense infiltrate of lymphocytes and another immune cells It is seen in the deepest part of the hair follicles in alopecia areata [4].
• The miniaturization of hair follicles (when the follicles produce progressively thinner hairs) and terminal hair to hair relationship is seen in male/female pattern hair loss [2,8].

What are the treatment and outcome of diffuse alopecia?

The treatment and forecast of diffuse alopecia depend on the underlying cause.

Telogen effluvium

Acute Telogen effluvium resolves within three to six months and hair density returns to normal by providing triggers or causative medications (see Drug-Induced Alopecia). [5]. Treatment is generally not necessary [6].

Hair loss that lasts more than six months is known as chronic telogen effluvium. It tends to fluctuate over a few years, then usually resolves spontaneously [5].

Anagen Effluvium

Anagen effluvium is managed with observation and support. [2].

• Cooling the scalp may reduce chemotherapy-induced alopecia (see Skin toxicity of chemotherapy drugs) [10].
• Anagen effluvium usually resolves once chemotherapy is stopped; permanent alopecia is rare [6].

Diffuse alopecia areata is difficult to treat. Even when treatment induces an increase in hair growth, hair loss can recur when treatment is stopped. [1].

• For adults with less than 50% scalp involvement, treatment with intralesional corticosteroid injections may temporarily accelerate regrowth [1,6].
• Short-term regrowth can be observed with current corticosteroids, minoxidil, immunotherapy (e.g., with diphenylcyclopropenone), and dithranol [1].

• Systemic corticosteroids can lead to regrowth, but the risks of long-term steroid use outweigh the benefits [1].

The natural course of diffuse alopecia areata is variable. One-third of patients recover spontaneously within six months, and 50-80% of these patients have persistent hair after one year. Some patients may have repeated episodes of diffuse alopecia areata [4,9].

The new hair that grows back may not be the same color or texture as before it was lost [9].

The prognosis is worse for alopecia areata that is severe at onset. Less than 10% of patients with alopecia totalis and alopecia universalis will recover [1].

Male and female pattern hair loss

Treatments for pattern alopecia must continue indefinitely, as discontinuation results in recurrent hair loss. [4,6]. Treatments include:

• Topical minoxidil solution – it usually takes 6 to 12 months before improvement is seen [4,6]
• Oral Finasteride – Used for male pattern hair loss [4]

• Antiandrogen therapy for women includes oral spironolactone, cyproterone acetate, and finasteride, but there is limited evidence of effectiveness [8].

Hairpieces and wigs and colored sprays or makeup can be used to camouflage bald areas.

Hair transplant It can be used to treat advanced male or female pattern hair loss [4].