Scarring alopecia: types, causes, diagnosis and treatment

Most hair loss, such as male and female pattern hair loss or alopecia areata, leaves the hair follicle intact and therefore capable of regrowth. In scarring alopecia the follicle itself is destroyed. Inflammation around the hair root damages the stem cells that make new hairs, and scar tissue takes their place. Where this has happened the scalp looks smooth and shiny, with no visible follicle openings.

There are several types. The most common are lichen planopilaris (LPP), where the skin condition lichen planus affects hair-bearing areas, and frontal fibrosing alopecia (FFA), which BAD considers may be a variant of lichen planopilaris. Others include central centrifugal cicatricial alopecia, discoid lupus of the scalp and folliculitis decalvans. Because the groups differ in treatment and outlook, accurate diagnosis by a dermatologist matters.

BAD describes lichen planopilaris as between 2 and 5 times more common in women than in men, usually affecting people aged 40 to 60. The crown and vertex of the scalp are most commonly affected, and face and body hair can also be involved.

Frontal fibrosing alopecia, according to BAD, occurs most often in post-menopausal women. The frontal hairline recedes slowly in a band and eyebrow and body hair can also be lost. Graham Little syndrome is a related condition in which patchy scalp hair loss occurs together with loss of armpit and pubic hair and a bumpy, sometimes itchy rash on the body and limbs.

BAD says lichen planopilaris causes redness and scaling of the skin around the base of hairs and blocking of the hair follicle, which may make the scalp feel rough. Where hairs have been destroyed the scalp may look smooth and shiny. It often occurs in patches but may involve larger areas.

For frontal fibrosing alopecia BAD says there may be no symptoms or an itchy, painful or burning sensation in a band across the frontal hairline, with redness and flaky skin around individual hairs. Once a hair has fallen out it does not regrow in the affected area, and the skin left may appear slightly paler and smoother. BAD also notes that many people find hair loss distressing, and that is a legitimate part of the consultation.

The cause is not fully understood. For lichen planopilaris, BAD says T-lymphocytes, a type of white blood cell, are involved and the hair follicle is attacked by the immune system, but nobody knows why it starts. For frontal fibrosing alopecia BAD says lymphocytes attack the hair follicles and that genetics, overactivity of the immune system and possibly hormones are thought to play a role.

Neither condition is contagious. BAD says lichen planopilaris is not inherited, although there may be immune genes that increase the risk, and that frontal fibrosing alopecia is not an inherited condition although it has occasionally been reported in more than one family member.

A GP will usually refer to a dermatologist, ideally with an interest in hair. Alopecia UK says that in most cases the typical appearance of FFA is enough for a dermatologist to make the diagnosis, and that if there is uncertainty they may take a small piece of skin from the edge of an affected area.

BAD explains that a scalp biopsy for lichen planopilaris may involve removing at least two small areas of affected scalp skin under local anaesthetic, which leaves small scars. Photographs or measurements may be taken in clinic to help assess disease control over time. Blood tests may be done to look for associated conditions or before starting some medicines.

BAD says there is no single proven effective treatment for lichen planopilaris, that success rates are very variable and that some people do not respond to any treatment. You do not have to have treatment. For frontal fibrosing alopecia it says treatments can slow or halt further hair loss in follicles that are inflamed but not yet lost, but cannot restore areas where follicles have gone.

BAD says that lichen planopilaris is a long-term condition but in most cases becomes inactive eventually, although hair loss is usually permanent. The aim of treatment is therefore to reach that stage with as much hair as possible, and to keep checking in with the dermatology team so that flare-ups are treated early.

Hair loss is often distressing, and many people find wigs, hairpieces, scalp camouflage, hairstyles or head coverings helpful. Charities such as Alopecia UK provide information and support. It is reasonable to tell your GP if hair loss is affecting your mood or confidence, because talking therapies and peer support are available.

Be cautious about unproven treatments sold online, and speak to a dermatologist before considering any procedure such as hair transplantation, because the disease may still be active.

See a GP if you notice patchy hair loss with a sore, itchy, burning or scaly scalp, a hairline that is receding in a band, or loss of eyebrows. Because scarring is permanent, earlier assessment gives more hair a chance of being preserved.

See a doctor sooner if there are pus-filled spots, crusting, oozing or a painful scalp, which may indicate infection or another type of scarring condition.

On the NHS the route is from the GP to a dermatology department, with a biopsy and a treatment plan reviewed regularly. Some departments run dedicated hair clinics.

Private consultant dermatologists can offer earlier appointments, dermoscopy and a second opinion. Because the disease course is long, make sure there is a plan for who prescribes and monitors any tablets that need blood tests.