Diagnosis

The diagnosis Lichen ruber planus can usually be made by a doctor by examination with the naked eye. In addition to the surface of the skin, the oral mucosa is also examined, as it is often affected by nodular lichen. Typical are small skin nodules (papules) as well as a net-like white striation of the nodules and mucous membranes.

This striation is particularly noticeable after a drop of edible oil or water has been applied to the affected areas. In case of doubt, the diagnosis is confirmed by microscopic analysis of tissue samples. Characteristic for Lichen ruber planus is a thickening of the uppermost skin layer (hyperkeratosis) and a spot-like thickening in the granular layer of the skin (hypergranulosis).

This leads to the net-like white stripe. With the help of a special staining process, antibodies are made visible which are deposited underneath the epidermis. Special immune cells can also be found there, which are responsible for the inflammation. Furthermore, blood tests are very useful, especially with regard to a hepatitis B or hepatitis C infection. These findings ultimately confirm the diagnosis of a lichen ruber planus.

Associated symptoms

The accompanying symptoms of Lichen ruber planus are very diverse and can affect not only the skin but also various parts of the body, such as the mucous membrane, hair or fingernails. Inflammatory, sharply defined reddish or brownish nodules and spots (papules) appear on the skin, which are very itchy. These nodules are mainly found on the flexor sides of the wrists, lower legs, lower back and knee bends.

Since scratching the nodules is extremely painful, there are no scratch marks despite the strong itching. In addition to the brownish hyperpigmentation, the affected areas may show fine milky white streaks (Wickham’s streak). The spots often form small groups that eventually combine to form larger skin changes (plaques) and are covered with a strongly thickened, yellowish horny layer (hyperkeratosis).

If the mucous membranes are affected by nodular lichen, one speaks of Lichen ruber mucosae. The focus of inflammation is typically covered with a clearly visible net-like white layer. The areas can be completely painless or stingingly burning.

In males, these changes are most noticeable on the glans, apart from the oral mucosa.Women have the typical changes especially at the entrance to the vagina. In addition to the skin and mucous membranes, the hair can also be affected (Lichen ruber follicularis or planopilaris). Mostly this form of nodular lichen appears on the body hair on the upper body and thighs, sometimes the scalp is also affected.

In this case, small horny plugs form in the area of the hair follicles, causing the hair to die and fall out. The affected areas feel very rough and the skin flakes off more. In the course of the disease, the hair is lost and scarred, bald areas develop.

Finger and toenails can also be affected by Lichen ruber planus and become brittle, shortened and get grooves. In Lichen ruber mucosae, in addition to the oral mucosa, the lateral parts of the tongue are usually affected. The changes in the mucous membrane can cause pain, burning and open sores.

Patients complain of dryness and a “furry feeling” on the tongue, and occasionally taste disorders occur. The oral form of lichen ruber is one of the most common diseases of the oral mucosa. The disease can occur in isolation or in combination with lichen ruber planus of the skin.

Autoimmune processes in the mucosa are suspected as the cause, but dental materials (e.g. amalgam) or certain drugs can also affect the lesions of the mucosa in the context of nodular lichen. A distinction is made between two forms of oral lichen ruber mucosae: the white or reticular form, in which the nodules are covered with a whitish, non-wipeable film, and the red or erosive form. The latter occurs more frequently, is characterized by extensive erythema and erosion and can be very painful.

The burning skin changes are more persistent in the area of the oral mucosa than on the skin. In addition to the mouth, tongue, gums and cheek mucosa, the oesophagus and larynx can also be affected. The typical whitish Wickham’s streak is much more pronounced than in the case of nodular lichen of the skin.

The changes in the mucous membranes can be painless or can cause severe burning, causing the patient great pain when eating or oral hygiene. The mucous membrane of the genital area is less frequently affected by Lichen ruber mucosae than the oral mucosa. Changes in the mucous membrane occur in men in the area of the glans and in women at the entrance to the vagina and on the inside of the labia.

They are clearly visible and shimmer slightly in the light. The skin appears dry and taut. There may be individual nodules or coherent white plaques.

Itchy and burning lesions develop, which lead to problems during urination and sexual intercourse. The fingernails can also be affected by lichen ruber planus. This leads to longitudinal rippling of the nail, which can also split completely in the further course of the disease.

The nail plates shorten and fray out. The nodular lichen leads to the fact that the nail becomes ever thinner and in the worst case can fail completely. Due to the failure of the nail, the nail bed grows together with the cuticle and bulging scars develop.