Trichotillomania Clinical Presentation

Patients with sharply defined alopecic lesions with broken stumps have a tendency to confess their manual hair manipulations if asked about them by a physician, while patients with poorly circumscribed alopecic lesions have a tendency to give very ambiguous answers. During the interview, the latter patients' answers may confuse an inexperienced physician, and they should not be confused with malingering.

Remember that hair manipulations frequently occur while patients are engaged in sedentary activities, such as reading, writing, watching television, or driving a car, and that their daily time allotted to physical exercise is scant.

Patients or their parents often claim the hair does not grow longer than approximately 1.5 cm; these patients or parents believe the hairs are suffering from periodical loss. Some patients may report pruritus of the scalp without visible dermatoses or may confess that they tried to remove nits or had a curiosity about hair roots and wanted to make an observation of the roots.

To obtain an effective history, a high index of suspicion for the diagnosis is essential. Also be aware that sleep-isolated trichotillomania is a recognized variant.^[10] Many cases erroneously diagnosed as alopecia areata are thus diagnosed because of the physicians' lack of suspicion about the possibility of trichotillomania. Remember that trichotillomania can occur in people from all walks of life and in any type of person.

For dermatologists who pay close attention to morphology, the diagnosis of trichotillomania is usually not a difficult one. The general morphology of an individual lesion, showing a geometrical shape and incomplete nonscarring alopecia of the involved area, is typical of trichotillomania (see the images below).

However, if the lesion is limited to an eyebrow or eyelash, the characteristic geometrical shape may not develop; this lack of a geometric pattern sometimes draws suspicion away from a diagnosis of traumatic alopecia (see the image below).^[11]

Occasionally, the hair-thinning pattern is not circumscribed and shows only a somewhat deficient volume of hair (see the image below).

Involvement of the entire scalp also occurs, in which a particular geometrical shape is also not recognized. At first glance, this type of trichotillomania resembles a hereditary disorder of keratinization such as monilethrix or pili torti (see the image below).

The patches may be single or multiple. The degree of involvement may vary from only a few square centimeters to the entire scalp. An extensive involvement of the scalp, sparing only marginal areas, is termed tonsure trichotillomania, after the monks in the Middle Ages whose hair was tonsured (see the image below).

Examination of the lesions with a magnifying glass reveals various combinations of (1) newly growing short hairs with tapered ends, (2) broken short terminal hairs, (3) vellus or indeterminate hairs, (4) comedolike black dots, or (5) empty follicular orifices (see the image below).

A contrast card positioned at an involved area (ie, a white card for black hair) is helpful to detect both the broken shafts and the newly growing hairs with tapered tips (see the image below).

With the popularity of digital cameras, physicians can easily show the traumatic nature of the alopecia to the patients and parents during the interview. In severe long-standing lesions, the hairs are regressed to vellus type hairs, and the lesional surface is almost smooth, similar to a scarring alopecia (see the images below).

In addition to scalp lesions, other hairy areas, such as eyebrows, eyelashes, or the pubic area, may be involved. Additionally, extremely short fingernails (from nail biting or onychophagia) frequently accompany trichotillomania, especially in children. Knuckle pads caused by frequent cracking or rubbing of the digits may also be found.

The cause of the repetitive behavior is largely unknown, although both environmental and genetic causes are suspected. Information has been gathered that may be helpful to understand the phenomenon.

In the relatively rare variant infancy-onset trichotillomania, lack of a transitional object is regarded as a cause for the hair pulling. During infancy, the baby is growing by touching a variety of transitional objects, such as the mother's skin, clothes, and toys, among other items. In a study of 9 cases of infancy-onset trichotillomania, the authors found that most of the patients had no transitional object, characterized by a lack of maternal physical contact and warmth.^[3]

In childhood and early adolescence, most patients with trichotillomania do not have sustained, focused awareness of their hair pulling in order to control the increasing tension during the behavior. Although tension and relief in relation to the hair pulling are included in the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV),^[5] deliberate hair pulling is rare in this age group.

Reeve et al found that only one child experienced tension before hair pulling and relief associated with hair pulling among the 10 children with trichotillomania they studied.^[12] However, in the author's 32 childhood and adolescent cases, the percentage of patients whose parents, one side or both sides, were absent was 12.5%, compared with an age-matched rate of 1.9% in general population.^[13] Thus, patients with trichotillomania may have some type of emotional problem in their family but far more trichotillomania patients are from intact families.

Even though hair has significant symbolic meanings in psychiatry, such as a recipient of feelings like rage and destruction or autoeroticism,^[14] no evidence indicates that people with trichotillomania are more nervous than those without the disorder or have a deeply rooted mental problem, at least in children and adolescents.

In adult patients, who are thought to be of a focused type in general, whether trichotillomania is a form of obsessive-compulsive disorder or not has been debated. In current DSM-IV diagnostic criteria, trichotillomania is classified as an impulse control disorder, but heterogeneity in its psychology is apparent and overlap with obsessive-compulsive disorder is suggested.

In neurobiology, a link between serotonergic activity and grooming behaviors similar to hair pulling has been reported in animals.^[15] Serotonergic dysfunction is also suggested in persons with obsessive-compulsive disorder characterized by unwanted repetitive behavior. However, only very limited numbers of patients with trichotillomania have obsessive-compulsive disorder, in which obsessions are a central feature. Reports also suggest a possible association between neurodegenerating diseases, such as Parkinson disease, and trichotillomania; however, too few cases are reported to warrant an evaluation.

Chronic hair pulling (along with motor and phonic tics) is also one of the symptoms of Tourette syndrome, which is a disease of the nervous system. However, most patients with trichotillomania do not have detectible neurological disorders.

Regardless of the neurobiological and psychiatric explanations, hair itself is a good, possibly the best, object for repetitive behavior. Hairs are free, are always available, and have a very flexible structure that is attractive. In most patients with trichotillomania, some form of stroking, twisting, or rubbing of the hair precedes the pulling behavior itself. Playing with the plucked hair (eg, rolling it in the fingers, rubbing it along the mouth) is also important for these patients. Interestingly, throughout history, females generally keep longer hair styles than males and the number of female patients with trichotillomania far exceeds the number of male patients.

Although the name trichotillomania suggests the act of plucking or pulling out, actual plucking seems to be a minor component in the total hair manipulations of trichotillomania patients. A certain force of pulling induces premature entry of the hair follicles into the catagen phase instead of immediate removal of the hair, which subsequently leads to increased hair loss. Likewise, repeated minor trauma to the hair makes the already-manipulated hair more vulnerable to subsequent injury, resulting in hair that is more easily broken. In short, unintentional and unconscious handling of hair plus in combination with physically developed damage to the hair causes patients to believe that the alopecia is caused by a disease of the hair itself, not by the trauma from their own hand. Thus, patients and their parents come to believe that the alopecia may be a real dermatological condition.

Twin studies and a knockout mouse model have shown that variants in the SAP90/PSD95-associated protein (SAPAP) gene are associated with obsessive grooming behaviors such as trichotillomania, and with obsessive-compulsive disorder (OCD) in both humans and mice.^[16] Haplotype analysis of SAPAP3 variants in the South African white population by Boardman et al found a significant association between an ATAT variant of the gene and early-onset OCD, but failed to establish a significant association of specific variants with trichotillomania.^[17]