Trichology: diseases — симптомы, диагностика и лечение

Dandruff and seborrheic dermatitis of the scalp are not two different diseases, but different expressions of one process: dandruff is its mild form without obvious inflammation, and seborrheic dermatitis is the same story, but with redness, itching and spread beyond the scalp. The reason for this process is not dirt or dryness, as is commonly thought, but the skin’s reaction to the yeast-like fungus Malassezia, which lives in all people and feeds on the components of sebum. This leads to the main practical misconception that has been preventing people from coping with the problem for years: the belief that the scalp is “dry” and needs to be washed and lubricated with oils less often. In fact, oils feed the fungus, infrequent washing accumulates grease and scales, and the condition only worsens. Proper care is exactly the opposite.

Hypertrichosis is excessive hair growth on any part of the body, not associated with the action of male sex hormones. Hair becomes longer, thicker and darker where there would normally be little of it, while the distribution remains “neutral” rather than masculine. This distinguishes hypertrichosis from hirsutism, in which in women hair grows in a male pattern - on the face, chest, abdomen - due to excess androgens. The reasons are different: hereditary characteristics, taking a number of medications, prolonged malnutrition, metabolic disorders, local skin irritation and, very rarely, congenital syndromes. Hypertrichosis itself is not dangerous, but sometimes it serves as a clue to another disease, so it’s worth checking with a doctor.

Hirsutism is the growth of coarse dark hair in women in areas where they usually appear only in men: above the upper lip, on the chin, around the nipples, along the midline of the abdomen, on the back and inner thighs. The basis is either an excess of male sex hormones or increased sensitivity of the hair follicles to their normal level. Most often, hirsutism is caused by polycystic ovary syndrome, less often by congenital dysfunction of the adrenal cortex, tumors, and the use of certain medications. This is not just a cosmetic problem: it may indicate a hormonal imbalance that affects your cycle, weight and ability to get pregnant.

Telogen effluvium hair loss is the most common cause of sudden diffuse thinning. Each hair lives in cycles: it grows for several years, then goes into a resting phase and falls out. If the body experiences a severe shock - high fever, surgery, childbirth, sudden weight loss, iron deficiency or thyroid disease - immediately most of the follicles go into rest ahead of schedule. The loss becomes noticeable two to three months after the event itself, so the patient usually does not see a connection with the cause. Hair thins evenly over the entire head, but the follicles are preserved, and after eliminating the cause, growth is restored.

Hair fragility is a condition in which the hair breaks off along the length or splits at the end. Hair consists of a dense protein core covered with cuticle scales: while this shell is intact, the hair is elastic and shiny. Aggressive coloring, hot styling, hard elastic bands, sun and dry air destroy the scales, the core loses moisture and begins to crumble. Less commonly, the cause is internal: iron deficiency, thyroid disease, malnutrition, rare hereditary disorders of the hair structure. It is important to distinguish fragility from hair loss: with fragility, the hair remains in the skin, and its shaft breaks off.

Onychodystrophy is a collective name for changes in the shape, thickness, color and strength of nails that are not directly related to infection. The nail plate grows from the matrix at the base of the nail, so any damage or systemic trouble is reflected on it with a delay of months: on the hands, the nail is completely renewed in about six months, on the feet - up to one and a half years. Hence an important conclusion: the changes that are visible today often indicate events six months ago. Most often, the causes are household and reversible, but sometimes nails are the first to indicate iron deficiency, thyroid disease or skin disease.

Gray hair occurs when the pigment cells in the hair follicle stop producing melanin, leaving the growing hair uncolored. This is a natural process, but the timing of its onset varies greatly from person to person and is primarily determined by heredity: if the parents turned gray early, the same is likely to happen in their children. Gray hair is considered premature when it appears noticeably earlier than the normal age for its population. Sometimes there are removable causes behind early graying - deficiency of vitamin B12, iron, thyroid disease, smoking - and then it makes sense to get examined, although it is impossible to return the color to already gray hair.

Trichotillomania is a disorder in which a person periodically pulls out his own hair: on the head, eyebrows, eyelashes, and less often on other parts of the body. This is not a whim or a sign of weak will: pulling out brings short-term relief from internal tension, and then a feeling of shame and attempts to hide bald spots. The disorder is classified as a group of repetitive behaviors directed at one's own body and is considered alongside obsessive-compulsive disorder. It most often begins in adolescence, and is much more common in girls and women. Hair usually grows back if you can stop pulling it out, and the main method of help is psychotherapy, not hair growth products.

Seborrheic dermatitis is a chronic inflammation of the skin in areas rich in sebaceous glands: scalp, eyebrows, wings of the nose, nasolabial folds, behind the ears, chest and back. Its most famous manifestation is dandruff. A key role is played by the yeast-like fungus Malassezia, which normally lives on the skin, but when there is excess sebum, it multiplies and causes an inflammatory reaction. The disease is chronic and prone to relapse, but is well controlled - provided that treatment is not stopped the day the peeling disappears.

Hair loss is a complaint that is associated with completely different conditions: from a temporary reaction to stress or illness to irreversible scarring baldness. This is why “anti-hair loss shampoo” helps so rarely: you need to treat the cause, not the symptom. The first thing you should know: losing 50–100 hairs per day is normal. A persistent increase in hair loss, thinning of the parting, and the appearance of bald patches or areas of complete baldness are considered alarming.