The patient who loses hair: alopecia

1. Gastroepato
2. Dermatology
3. The hair loss
4. Skin lesions
5. The tinea capitis
6. Scabies  

notes by dr Claudio Italiano 

Alopecia, a word that derives from the Greek alopecs and which means fox, since the fox loses the hair in patches in spring, manifests itself more frequently on the scalp, usually develops gradually and can be:

a) diffused
b) in patches.
c) cicatricial
d) not cicatricial.

Scarring alopecia is defined in this way because there is permanent loss of hair, because the hair bulb, which is the organule from which the hair originates, is destroyed. Then the skin becomes smooth and the follicle outlets disappear. Non-scarring alopecia is defined as the momentary loss, caused by damage to the hair follicles that saves the follicle outlet, so that the future hair regrowth is possible. For example, a temporary loss is due to chemotherapy or due to the use of other medications, radiotherapy, connective tissue diseases, tumors, endocrine diseases, eating disorders with malabsorption, etc.

Why alopecia?

Nomally, each person loses about 50 hairs a day, which are replaced by new hair. The hair grows through three distinct moments: anagen, catagen and telogen.

Anagen

This is the most important phase of growth in which the cells of the bulb of the hair bulb live a metabolic activity. The anagen phase, ie hair growth, varies on average from 3 to 6 years. The hair is never all in the same phase of growth, except in particular pathological conditions, but they grow so different from each other that it is difficult to find two contiguous follicles in the same phase. Hair during the anagen phase grows 0.3-0.4 mm per day.

Catagen

 It is the phase of involution, which lasts from 2 to 3 weeks, during which the hair follicle undergoes various morphological and metabolic modifications. The lower segment disappears, the length of the follicle is reduced by about a third, the papilla becomes atrophic, the bulb decreases in size and the melanocytes cease the production of pigment. If you tear a hair at this stage you can see that its terminal part, corresponding to the bulb, is white. The various alterations that occur lead the hair to its last telogen phase.

Telogen

It is the resting phase during which the follicle is completely inactive and as wrapped in a connective tissue bag that offers it shelter until the beginning of the new growth phase. The hair is inside the follicle, retained by poor intercellular ligaments that make it remain in the scalp until the beginning of the new phase of anagen and sometimes even for several successive phases. The telogen phase lasts from 2 to 4 months. At these various stages of the hair follows its fall. Every day about 10-30 hairs die, which under ideal conditions are immediately replaced by new elements, because the follicles have vital cycles synchronized with each other: in fact, the total volume remains unchanged. When a pathogenic noxa (psychological stress, a metabolic problem, a hormonal disorder) causes the follicles to pass from an anagen to the telogen phase, then an alopecia is determined. A third phenomenon is the increase of the kenogen phase: when the hair shaft comes off at the end of the telogen. Thus aging, genetic predisposition and hormonal modifications can contribute to the gradual thinning of the hair and the retraction of the hairline. This type of alopecia occurs in around 4%% of adult men and can also occur in postmenopausal women. People who have thin, relatively sparse hair like natives of tropical areas may not immediately recognize alopecia. In men, hair loss more often affects temporal areas, producing a hairline in the shape of M. In women, widespread thinning affects the center-frontal area. In both sexes, hair loss also occurs on the trunk, pubis, armpits, arms and legs. In the woman it is possible in the post-partum period, during the lactation, between the second and the fourth month. This loss of hair, widespread and transient, can be scarce or dramatic and probably accentuated in the frontal areas. Anxiety, high fever, and even certain hairstyles or methods of combing (for example, boys using fixative gel!) can cause alopecia.

Anamnesis and objective examination

If the patient is not being treated with chemotherapy or radiotherapy, ask from the beginning when he first noticed the thinning or hair loss. Does it affect only the scalp or the whole body? And accompanied by itching or rash? Then you must carefully seek other signs and symptoms that can help you distinguish between a normal or pathological loss of hair. Ask about recent weight loss, anorexia, nausea, vomiting and modification of the alvo. Also inquire about alterations of urine, such as hematuria or oliguria. Has the patient been particularly tired or irritable? Did you have a cough or difficulty breathing? Investigate the presence of arthritic pain or joint stiffness and intolerance to heat and cold. Ask the patient about the exposure to insecticides.

If the patient is a woman, it is necessary to find out if she has had menstrual irregularities and to collect the anamnesis on her pregnancies. If the patient is a man, he must investigate any sexual dysfunction, such as reducing libido or impotence. Subsequently. ask about hair care. Does the patient frequently use a hair dryer with hot air or electric curlers? Do you periodically use dyes or lighteners or do the permanent? Ask black patients if they use a hot comb to straighten their hair or a comb with long teeth to get an African look. Have you ever braided your hair? You must collect your family history of alopecia and ask at what age relatives have started losing their hair. Also gather information about the patient's emotional habits, that is, if he usually pulls his hair, he rolls it over his fingers.

The objective examination must begin by detecting vital parameters and then evaluating the extent and characteristics of hair loss from the scalp.

Is it patchy or symmetrical? Are the hair that surrounds a bald area fragile and dull? Do they have a different color than the other hair? They fall easily? The underlying skin should be inspected for follicle outlets, erythema, loss of pigment, scaling, hardening, broken hair and hair regrowth. Then, the rest of the skin is examined. The size, color, structure and location of each lesion must be noted. The presence of jaundice, edema, hyperpigmentation, pallor or hyperchromic areas should be monitored. The nails must be examined for the presence of vertical or horizontal depressions, thickening, brittleness or whitening. While doing this you must look for the fine tremors in your hands. The muscles must be observed to find the presence of muscular weakness or ptosis. They are then searched with the palpation of lymphadenopathy, increases in the volume of the thyroid or salivary glands and the presence of masses in the abdomen or thorax.

see  Alopecia parte seconda