Alopecia: causes, symptoms, diagnosis, treatment

Alopecia (baldness) is a pathological loss of hair on the head, face, and less commonly on the trunk and limbs.

A distinction is made between cicatricial and non-cicatricial alopecia. Cicatricial alopecia occurs as a result of the destruction of hair follicles as a result of inflammation, atrophy or scarring in lupus erythematosus, pseudopellagra, Little-Lassuer syndrome, follicular mucinosis.

Non-scarring alopecia develops without previous skin lesions (alopecia areata, androgenetic, anogen, telogen).

Alopecia areata is characterized by the appearance of oval or round bald spots on the scalp and face. According to American researchers, about 1% of the US population by the age of 50 has suffered from alopecia areata at least once, and about 0.1% of the entire population has experienced hair loss at least once. The disease is equally common in both women and men, in representatives of all races, and is distributed relatively evenly across all continents.

Causes and pathogenesis of alopecia. To date, the etiopathogenesis of the disease remains debatable, and all the points of view under consideration (nervous, immune, endocrine, etc.) have equal rights to exist.

Most authors suggest an autoimmune mechanism of hair follicle damage. Changes in the content of T- and B-lymphocytes, an increase in immune complexes and the presence of lymphocytic infiltrates around hair follicles and antibodies against hair follicles in patients with alopecia have been identified. Alopecia areata is often combined with other autoimmune diseases (Hashimoto's thyroiditis, nodular goiter, vitiligo, autoimmune polyglandular syndrome, etc.).

Symptoms of alopecia. There are focal, subtotal, total and universal forms of alopecia. In the focal form, hair falls out gradually, bald spots form over several weeks or months. Hair loss may be insignificant and unnoticeable to the patient. In the affected areas, hair growth resumes after some time, but at the same time new bald spots appear. The skin in the bald spot is usually unchanged. In some patients, in the first days of the disease, a slight redness can be seen in the bald spots, which is accompanied by itching, burning, hyperesthesia of the skin. Subsequently, the redness disappears, and the skin, deprived of hair, acquires its normal color or the color of ivory. The bald spots are oval or round, single or multiple. Along their periphery, the hair is unstable and falls out in small clumps when gently pulled (zone of loose hair). This diagnostic sign is characteristic of the progressive stage of the disease. Empty mouths of hair follicles are visible on hairless skin. The lesions expand along the periphery, neighboring lesions merge into one large lesion. The size of the lesions ranges from several millimeters to several centimeters. In the stationary stage of the disease, broken, short, dark-colored hair is found, which can cause diagnostic errors. The bald spots after a certain time, even without treatment, can spontaneously resolve, which corresponds to the regression stage. The bald spots can be localized on the scalp, eyebrows, eyelashes, in the pubic area, in the beard and moustache area. Sometimes alopecia acquires a malignant course. In this case, the bald spots increase in size and number. All hair falls out: on the scalp, face, vellus hair on the trunk, limbs, i.e. subtotal, total and universal forms of alopecia develop.

In subtotal alopecia, hair loss progresses slowly, bald patches gradually increase in size, and thick hair on the scalp falls out. Vellus and short hairs remain in the occipital and temple areas and in certain areas of the skin where there are thin, discolored single hairs that fall out when lightly pulled by the free end.

Total alopecia develops quickly, i.e. within 1-2 months, the hair on the head and face falls out completely. This form of alopecia is accompanied by various neurological disorders.

In universal alopecia, hair loss is observed not only on the scalp and face, but also on the trunk and limbs; nails (onycholysis, thimble symptom, longitudinal and transverse striations, increased fragility) and neurological status (vegetative-vascular dystonia, neurotic syndrome) also change.

Differential diagnosis. Alopecia should be distinguished from toxic, syphilitic alopecia, hair loss caused by dermatophytosis (trichophytosis, microsporia), trichotillomania.

Treatment of alopecia. Elimination of bad habits (alcohol consumption, smoking) and concomitant diseases. In the focal form, irritants (dinitrochlorobenzene, pepper tincture, etc.) are used, which cause artificial allergic contact dermatitis. External photochemotherapy, applications of strong and very strong corticosteroids, and injections of corticosteroids into the lesion have a good therapeutic effect. In subtotal, total and universal forms of alopecia, systemic corticosteroids or PUVA therapy are prescribed. However, after the withdrawal of corticosteroids, a relapse of the disease often occurs. Long-term use of steroids is undesirable due to side effects. In all forms of alopecia, in addition to the above therapy, it is advisable to prescribe vitamin therapy, biogenic stimulants and microelements.

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