Parapsoriasis en plaques benign small foci L41.3

Chronic, idiopathic, small-spotted dermatitis along the cleavage lines of the skin whose nosological position is not yet definitively established. There is no relationship to psoriasis. The relationship to non-tolent T-cell lymphomas is not established. S.a.u. Parapsoriasis en plaques.

Unknown. The cutaneous infiltrate consists mainly of CD4+ lymphocytes. In some cases a T-cell clonality has been detected. In these cases the risk of progression into T-cell lymphoma is about 20% over a 5-year period. Familial occurrence is described.

Occurs in adults between 30 and 75 (medium 50 years) years of age, rarely in childhood. Preferred in men. m:w=5:1; no preference of certain ethnic groups.

Mainly lateral parts of the trunk; furthermore extremities and face. Palmae and Plantae are always free. Capillitium and mucous membrane regions as well.

Numerous (usually more than 20), predominantly not exceeding the size of 2.0-5.0 cm, yellow-red or also light yellow, oval or roundish, but often finger-shaped stretched patches (tiger pattern) or also slightly infiltrated (hardly elevated), usually blurred plaques. Finger-shaped "patches" can also exceed the "5 cm limit" on the trunk and grow out to 10-12 cm. Only slight, barely visible, lesional desquamation.

Formation of larger plaques (patches) due to confluence.

Apparent coarsening of the skin patches due to the finest distortions of the horny layer; thus, image of pseudoatrophy of the skin: cigarette paper-like pleated skin without signs of atrophy in the histological substrate.

In rare cases, there is a "psoriasis-like" aspect with nummular plaques, markedly increased in consistency and elevated.

A special form is parapsoriasis en gouttes leucodermiques (Lortat-Jacob and P.Fernet 1923). In this case, a white halo forms around the parapsoriatic plaque, which can persist for a long time after the inflammatory plaque has subsided.

Superficial, interstitial lymphocytic (predominantly CD4+ cells) dermatitis with discrete acanthosis, mocking, mostly low spongiosis, only focal, discrete epidermotropia without parakeratosis.

Phototherapy or balneo-phototherapy with UVA1 or UVB rays.

Alternatively, PUVA therapy (PUVA should be used with caution because of possible permanent damage).

Dermatological climatic therapy (maritime climate ), which generally leads to significant improvement.

In case of UV-resistant foci, try external steroids (e.g. Ecural fat cream). Otherwise, external care measures such as greasing lotions (e.g. Lipoderm Lipolotio) or creams containing saline R146 or creams and ointments containing urea.

Sparing use of cleansing agents such as syndets or soaps.

Instead, use hydrophilic body oils as wash substitutes, which are generally used as oil baths (e.g. Cordes Oil Bath, Linola Fat N Oil Bath, Balneum Hermal Oil Bath).

Alternatively, oil/surfactant combinations are also possible (e.g. Eucerin shower oil).

Benign, eminently chronic course, marked improvement under sun or UV irradiation. In the summer months the skin changes can disappear completely under the influence of the sun. However, they recur regularly during the dark season. Rarely healing.

Some studies doubt the absolute "benignity" of this small-focus form of parapsoriasis, which has so far been seen contrapuntally to the malignant large-focus variant (precursor of mycosis fungoides). In larger collectives the transition to a relevant T-cell lymphoma is given with 1:30 (Belousova IE et al. 2008)

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