Trichorrhexis nodosa is a condition that results in breakage and difficulty in growing the hair out, due to the development of small growths or nodes on individual hairs. This disorder occasionally has a congenital cause, but it is more often acquired due to extensive damage to hair or sometimes to malnutrition or diseases like hyperthyroidism. The condition can be diagnosed by evaluating the hair shaft. Treatment may then address any underlying causes and also work on minimizing hair stress to avoid the development of additional nodes.
In almost all cases where this condition is due to congenital causes, the link is indirect. Trichorrhexis nodosa develops because another inherited disease weakens the hair. This fragility appears to predispose it to the development of nodes.
For example, argininosuccinic aciduria deprives the hair of arginine, making it susceptible to breakage and more likely to develop growths. Another condition, Menke’s disease, causes the body to metabolize copper poorly, which in turn affects the ability to create keratin. Vital to hair health, keratin must be present in sufficient amounts; otherwise hair will be weak, which may encourage the development of trichorrhexis nodosa.
Similarly, the presence of significant malnutrition or medical disorders like hypothyroidism may deprive the hair of nutrients and create scenarios in which trichorrhexis nodosa is more likely to occur. In most cases, there is no initial weakness of the hair and the condition develops through constant damage to the shafts. For instance, hard brushing, dying, and perming the hair can cause nodes to develop. Disorders like trichotillomania, or compulsive hair pulling, and behaviors like head banging may also damage the hair shaft.
It’s significant that trichorrhexis nodosa is most likely to develop in women who are middle-aged. In contrast, most congenital forms of the disease develop much sooner in life. This suggests that long-term repeated damage to the hair through things like brushing or perming makes people more at risk for this disorder.
Diagnosis of trichorrhexis nodosa is fairly straightforward. Under a microscope, a small sample of the hair is likely to show nodes or white spots. Once diagnosed, physicians must determine the cause. As mentioned, hard treatment of the hair is almost always at least partially responsible. Doctors might want to screen for other problems like malnutrition, hypothyroidism, or poor synthesis of certain body proteins and chemicals.
Addressing any underlying causal factors, when possible, partially treats the disease. Sometimes supplements are also prescribed to increase hair health. Patients also need to comply with behavioral changes so that the hair is not placed under stress. This can mean using very soft brushes on the hair; forgoing the use of curling irons and blow dryers; and avoiding hair dye, straightening procedures, or perms. Recovery can be challenging, taking two to four years, and some underlying congenital conditions might make it very hard to completely cure this disorder.