Terminal hairs

Toll, R., Jacobi, U., Richter, H., Lademann, J., Schaefer, H., and Blume-Peytavi, U. (2004) Penetration profile of microspheres in follicular targeting of terminal hair follicles. Journal of Investigative Dermatology, 123 (1), 168-176. 

Long, thick pigmented Androgen- J terminal hair sensitive regions... 

Toll, R., et al. (2004) Penetration profile of microspheres in follicular targeting of terminal hair follicles. J Invest Dermatol 123,168-76. 

Hirsutism is defined as the excessive growth of terminal hair in women and children in a distribution similar to that occurring in postpubertal True hirsutism, which... 

Hair follicles and their associated sebaceous glands (pilosebaceous glands), eccrine glands, apocrine glands, and finger and toenails are all considered skin appendages. Hair follicles are found everywhere within the skin except for the soles of the feet, the palms of the hand, the red portion (vermilion border) of the lips, and the external genitalia. All are formed from fetal epidermal cells. Hair differs markedly in its prominence from place to place over the body. Delicate primary hair is found on the fetus secondary hair or down covers the adult forehead terminal hair ordinarily blankets the scalp and is found as pubic... 

Hirsutism results from the change of hne, vellus hair to visible, thickened, terminal hair under the influence of dihydrotestosterone, a biologically active form of testosterone. This androgen-dependent hair growth develops in deflned patterns. Terminal hair is a normal phenomenon and is often found on the upper lip, the chin, aronnd the nipples and the midline of the lower abdomen. 

As indicated, terminal hairs is normally applied to those long thick hairs that occur on children and adults in contrast to lanugo and vellus hairs. 

Table 1-2. Differences between terminal and vellus hairs. Terminal hairs...

Hypertrichosis is a condition in which an excessive growth of terminal hair occurs usually on the limbs, trunk, or face. Hypertrichosis may be localized or diffuse. The most common type is called essential hirsutism or idiopathic hypertrichosis of women. In this condition, terminal hairs grow on women in those areas where hairiness is considered a secondary sex characteristic of males (e.g., the trunk, the limbs, or the beard or mustache area). This condition is generally not due to an endocrinologic abnormality but rather is believed to be linked to the transport of testosterone from the endocrine glands to the site of activity (see Figure 1-10). 

Endocrinopathic hirsutism is a rare condition that results from excessive synthesis of hormones with androgenic properties. This abnormality produces masculinization of females. One symptom of this condition is excessive growth of terminal hairs in regions that are normally hairless in females. Classic examples of this disease are often exhibited in circus sideshows. 

Hair loss is actually the transition of terminal hairs to vellus hairs. This condition occurs gradually and at different rates for different persons. This phenomenon tends to occur in a more diffuse pattern among women than among men. Thus, the term male pattern baldness is used for the patterns... 

Alopecia or hair loss may occur over any body region such as the scalp, face, trunk, or limbs. Obviously, alopecia of the scalp (baldness) has received the most scientific attention. In most forms of baldness, progressive miniaturization of hair follicles results in a transition of terminal hairs to vellus hairs [14] as opposed to the common misconception portrayed by the term hair loss. In a normal healthy scalp, approximately 80 to 90% of the hairs are in anagen, 1 to 2% in catagen, and 10 to 20% in telogen [15]. 

Alopecia areata, another form of hair loss, is believed to be related to the immune system (e.g., autoimmunity). This disease generally occurs as patchy baldness on an otherwise normal scalp, although sometimes hair of other body regions is affected. When the entire scalp is involved, the condition is called alopecia totalis. If terminal hair loss occurs over the entire body, a rare condition, it is called alopecia universalis. Emotional stress has been shown to be one of the initiating causes of areata. Topical application of steroids is sometimes used to treat this condition. 

Thus, any agent or process that either enhances or interferes with any of these five steps will lead to either less or greater production of longer more coarse hairs. Interference in the transport process of step 2 may result in terminal hairs produced where vellus hairs are normally produced. For example, the second step involving the transport of testosterone on carrier proteins is the effect seen in most hirsute women [24]. What is observed is a reduction in transport proteins (SHBG) and the concomitant increase in free unbound testosterone level in the blood stream. Thus, the transport mechanism is interfered with, and thick terminal hairs are produced in body regions where they are not normally produced. 

Different receptor proteins for stimulating or retarding hair growth help to explain the fact that, in the case of males at puberty, thick terminal hairs begin to grow in the axilla, the mons pubis, and the beard areas, in spite of increased levels of testosterone and, at a later time in life, increased levels of testosterone in the scalp help to cause male pattern baldness. 

Confluent follicular and perifollicular inflammations Intercommunicating cysts Recurrent draining sinuses and abscesses in skin folds that carry terminal hairs and apocrine glands Ulcerative nodules associated with systemic complications ... 

An initial response was defined as appearance of new terminal hair at treated sites an excellent response was defined as terminal hair covering over 75% of the scalp. Relapse meant more than 25% hair loss. Maintenance therapy meant therapy once every 1-4 weeks. After the initial 3 months, there were excellent responses in 15, 47, 51, and 55 patients after 6, 12, 18, and 24 months respectively. The only patient variable that affected the prognosis was the baseline extent of alopecia. Adverse reactions were few and tolerable. 

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