Lichen nitidus is a rare dermatitis, of unknown etiology, characterized by small papules of normal skin color, with a bright surface, generally asymptomatic (it does not generate symptoms), located preferably in the flexor region of the elbows, genitals, and trunk, although they can be distributed anywhere in the skin.
Its evolution over time is variable since it can spontaneously remit in the term of months to years. So far there is no effective treatment for the injuries.
Lichen nitidus (LN) was described and characterized by Felix Pinkus in 1901 and 1907 respectively. It is a skin rash, usually asymptomatic, consisting of the presence of small papules of normal or slightly pink skin, with a bright surface, each one of 1 to 2 mm in diameter, rounded, smooth and separated from each other, which most often affect folds of elbows and wrists, breasts, glans, body of the penis and lower abdomen, but more rarely they can spread to any part of the body and become generalized.
How is Lichen Nitidus Treated?
The lichen nitidus is an asymptomatic and self-limiting entity, which usually does not require treatment. This is justified in those cases where there is pruritus (itching) or where the appearance and extension of the injuries alter the daily life of the patients.
Topical and systemic corticosteroids can be used with relative efficacy for the remission of lichen nitidus lesions.
Other treatments include psoralen, PUVA (psolaren and ultraviolet A) and narrow-band UVB phototherapy along with glucocorticoids and acitretin.
Call your health care provider if small lumps or a condition similar to a rash appear on the skin for no apparent reason, such as a known allergic reaction or contact with poison ivy. Given the number of conditions that can cause skin reactions, it is better to get a quick and accurate diagnosis.
The mucous membranes and nails are rarely affected by lichen nitidus. Occasionally palms and plants can be compromised by presenting hyperkeratosis, fissures, erythema and the appearance of sandpaper. There are described cases of unilateral palmar presentation simulating a dyshidrotic eczematous dermatitis.
As rare variants, it can be mentioned the vesicular, hemorrhagic, follicular, spinous, linear, generalized and actinic types.
The clinical course is very variable with the spontaneous resolution being the most frequent, it has been described cases of remission between 1 year or less and 8 years. The papules heal without scarring, although there are publications that describe a residual hyperpigmentation after the disappearance of the papules.
As it is a rare entity, there is no data sustainable in terms of epidemiology, however, it seems to be more frequent in children and in the black race, presumably because the clear papules are more noticeable on a dark skin, existing predominance of the female sex in the generalized variant…
The pathological anatomy evidences a thinned epidermis, central parakeratosis, and absence of granular layer, a dense lymphohistiocytic infiltrate compact, with the appearance of being embraced (“ball and hook”) by neighboring interpapillary crests; these findings are characteristic. In the dermis, the infiltrate is well delimited composed of histiocytes and giant cells by a foreign body (Touton).
The diagnosis of the lichen nitidus is usually simple by morphology and distribution of injuries; eventually, the pathological anatomy will confirm it. The differential diagnoses of lichen nitidus should be considered with:
- Flat warts, but these are usually larger and more variable, rough surface, hardly affect more than one body area and are asymptomatic.
- Lichen spinulosus and papular eczema, which have keratotic and non-bright papules such as lichen nitidus.
- Keratosis pilaris, the presence of antecedents or other manifestations of atopic dermatitis such as xerosis and eczema outbreaks.
- Scrofulous lichen that affects young people with tuberculosis as a base pathology and whose lesions correspond to perifollicular papules.
- Syphilitic secondary education, Bowenoid papulosis, and amyloidosis are other occasional differential diagnoses to be taken into account.
The clinical course is unpredictable, with spontaneous resolution in months or years despite the treatment of lichen nitidus.
In most cases, it is not necessary to adopt any therapeutic measure since the lesions are asymptomatic and self-limiting; only if the lesions are very extensive or symptomatic the treatment with topical corticosteroids is indicated. Other treatments used in isolated cases have been tuberculostatic, antifungal and enoxaparin.
- Lichen Planus: Causes, Risk Factors, Signs, Symptoms, Investigations, Treatment
- Lichen Sclerosus (LS): Causes, Signs, Symptoms, Investigations, Treatment
- Pityriasis Lichenoides: Causes, Risk Factors, Signs, Symptoms, Investigations, Treatment
- Neurodermatitis or Lichen Simplex Chronicus: Causes, Risk Factors, Investigations, Treatment, Home Remedies & Prevention
- 8 Natural Treatment For Lichen Simplex Chronicus
- Is Pityriasis Lichenoides Chronica Contagious, Know its Causes, Symptoms, Stages, Treatment, Complications