What is Noncicatricial Pressure-Induced Alopecia?

Diagnosing the cause of a person's hair loss involves an in-depth analysis of the evidence that is available, but sometimes symptoms can be misleading as was recently discovered when doctors in Rio de Janeiro examined a 14-year-old girl.

The patient had lost her hair in several small patches in such a way as to suggest that it was caused by the autoimmune disorder Alopecia Areata. This condition will affect between one and two per cent of people in their lives, and has a number of suspected triggers, including stress, allergies and hormonal changes. Small, coin-shaped patches anywhere on the scalp are how the condition will typically manifest itself.

The patient's pressure-induced alopecia

Preceded by hospital stay

However, an important factor that made dermatologists in Brazil question whether she was indeed presenting with Alopecia Areata was that her two-month spell of patchy hair loss on the back of her head had been preceded by a stay in hospital because of complications with type-1 Diabetes. This had left her unconscious for four days, and she had spent a further seven days in hospital.

Could it be, they wondered, that her hairloss was caused by the pressure placed on hairs and hair follicles as she lay immobile in her hospital bed?

Writing about the case in the International Journal of Trichology, the doctors wrote that a microscopic evaluation (trichoscopy) of her scalp showed a number of broken and dystrophic hairs. Biopsies revealed hair follicle miniaturisation and pigment casts resembling Alopecia Areata but “without peribulbar inflammatory infiltrate” which is the expected histologic feature of Alopecia Areata. There were no signs of scarring.

The doctors concluded that their patient’s hair loss was caused by the rare hair loss condition Noncicatricial Pressure-Induced Alopecia and not Alopecia Areata. By “Alopecia” they simply mean hair loss, while “Noncicatricial” means there was no scarring present. As they state themselves: “Pressure-Induced Alopecia is an unusual cause of hair loss, and reports of its trichoscopic features are scarce.”

Prolonged pressure on the scalp

They say that Pressure-Induced Alopecia has been reported before after long periods of immobilisation during surgeries or after prolonged hospitalisation in intensive care.

It is usually characterised by tissue ischemia (lack of blood supply) caused by prolonged pressure on the scalp, as well as compression of the hair follicles with cessation of their activity.

Researchers point out that because the physical symptoms are so similar to Alopecia Areata, it would be easy to misdiagnose the condition, but suggest that once dermatologists make the link between the symptoms and a prolonged hospital stay, then the correct diagnosis becomes obvious.

"I do not recall any confusion with regards making a diagnosis. When people present with bald patches of this sort it is often a straightforward case of either alopecia areata or cicatricial hair loss. However, new conditions such as this do come to light occasionally and it is of course important for specialists to keep up-to-date with such findings," Senior Belgravia hair loss specialist Leonora Doclis explains.

"Although this has not yet been proven, the research is extremely interesting and backs the holistic approach we take to diagnosing clients. This involves not just examining the pattern of shedding or family history but also places importance on talking to patients to uncover any other factors which may be influencing their hair loss or the condition of their hair and scalp, that they may not have thought could be linked."

The incident is a reminder, perhaps, of how important it it to see a specialist when there are problems with the scalp or hair loss. Multiple conditions share similarities and many overlap, meaning that seeking help in getting the right diagnosis is always a solid starting point for anyone considering hair loss treatment.