[To the problem of parapsoriasis: classification problems (literature review and personal observations)].

In the presented article we discuss the problems of lichenoid and plaque parapsoriasis. The difference in Russian and English classifications are discussed in the historical aspect, as well as review of the literature, and personal authors' observations of nine patients with "small plaque parapsoriasis".

The conundrum of parapsoriasis versus patch stage of mycosis fungoides.

Terminological confusion with benign dermatosis, such as parapsoriasis en plaques, makes it difficult to diagnose mycosis fungoides in the early patch stage. Early diagnosis of mycosis fungoides (MF) is important for deciding on type of therapy, prognosis and for further follow-up. However, until recently, there has been no consensus on criteria that would help in diagnosing the disease early. Some believe that large plaque parapsoriasis (LPP) should be classified with early patch stage of MF and should be treated aggressively. However, there is no firm clinical or laboratory criteria to predict which LPP will progress to MF and we can only discuss about statistical probability. Moreover, long-term outcome analysis of even patch stage of MF is similar to that of control population. We therefore believe that LPP should be considered as a separate entity at least to prevent the patient from being given a frightening diagnosis. We also feel that patients need not be treated with aggressive therapy for LPP and will need only a close follow-up. This article emphasizes the criteria for diagnosing early MF and has highlighted the importance of considering LPP as a distinct benign entity.

Parapsoriasis lichenoides/parapsoriasis variegata--a new concept.

We present a new concept on the nosology of parapsoriasis lichenoides (= parakeratosis variegata) and show that this parapsoriasis type is not a separate entity. It represents different diseases: a large number of cases presenting as reticular parapsoriasis are mycosis fungoides, another group represents reticular variants of the parapsoriasis guttata group (pityriasis lichenoides acuta et chronica). Further, cases exist that can be classified as lichen planus reticularis or other diseases (e. g. keratosis lichenoides).

Parapsoriasis: a complex issue.

Parapsoriasis is a peculiar reaction pattern of the skin that appears to have a spectrum with small plaque parapsoriasis at one end and large plaque at the other. The spectrum between is bridged by pityriasis lichenoides, pityriasis lichenoides chronica, pityriasis lichenoides et varioliformis acuta, and lymphomatoid papulosis. The highlights of the clinical pattern of these diseases has been succinctly elucidated here to facilitate their recognition in day-to-day dermatologic practice. Their possible etiopathogenesis has been brought to focus in the light of changing concepts reported in the literature. Further, possible future implications demand a meticulous follow-up because, in a few cases, true neoplasms may ultimately develop. Treatment modalities are briefly discussed.

Parapsoriasis retiforme / Retiform parapsoriasis

La parapsoriasis retiforme es una enfermedad cutánea poco frecuente, la cual se englobaría dentro del grupo de las parapsoriasis de grandes placas. Clínicamente se caracterizan por la aparición de placas extensas, que evolucionan hacia la atrofia. Muestra un patrón de distribución típico reticulado. Existen casos descritos que progresan a linfoma cutáneo, por lo que es necesario, un seguimiento prolongado del paciente. Presentamos un caso de parapsoriasis retiforme de larga evolución (AU)

Parapsoriasis and related conditions.

Classification of parapsoriases is revised into a simple practical table. Pityriasis lichenoides (guttate parapsoriasis) is not a type of parapsoriasis. The clinical features of small patch and large plaque parapsoriasis are described in detail. Six clinical varieties of large plaque parapsoriasis and three clinical varieties of exfoliative dermatitis including Sézary syndrome have been clearly recognized as distinctive categories. Histopathology is useful for the diagnosis of parapsoriasis and mycosis fungoides. Sézary cell count is not significant for the diagnosis of Sézary syndrome.

Comparative clinicopathological study on pityriasis lichenoides chronica and small plaque parapsoriasis.

The term parapsoriasis refers to a group of chronic asymptomatic scaly dermatoses of unknown etiology about which there is still controversy over the nosology and nomenclature of the different conditions that comprise the group, particularly pityriasis lichenoides chronica (PLC) and small plaque parapsoriasis (SPP). In an attempt to establish the distinctive clinicopathologic features of these two dermatosis, we prospectively studied 44 patients who presented with the typical clinical and histologic picture of either of these two diseases. SPP was clinically characterized by scaly oval plaques on the trunk and proximal aspect of extremities. Spongiosis was the salient histopathologic feature, with absence of fibrosis or melanophages. PLC presented with a scaly papular eruption over the trunk and extremities and histologically was characterized by an interface dermatitis. We conclude that sufficient clinical and histologic features differentiate these two entities and we propose that the term parapsoriasis be used only to designate SPP and large plaque parapsoriasis.

The nosology of parapsoriasis.

Parapsoriasis is a group of uncommon but not rare disorders that was created in 1902 as part of a now long forgotten scheme to classify all inflammatory dermatoses. This artificial grouping has led to an enormously confused nosology of these disorders, that are, for the most part, otherwise unrelated. The use of a number of different terms at different institutions and by different physicians to denote the same diseases, together with the use of particular, single terms to denote different diseases, has caused much unnecessary confusion. In this review these terms are examined and an attempt is made to propose a new, unambiguous classification. Using this system, physicians with different views regarding which of the parapsoriases constitute distinct entities should have not difficulty communicating, and should have clearer frame of reference within which to work. An attempt is made to evaluate critically which of the parapsoriases are distinct entities and whether one or more of them should be considered an early form of cutaneous lymphoma in light of currently available data.

Parapsoriasis.

Parapsoriasis is a term which encompasses a number of differing pathologic states clinically manifesting chronic recalcitrant erythematous scaling lesions. Although these various diseases have some similar clinical and histopathological features, they are obviously quite different from the standpoint of malignant potential and prognosis. The classification suggested herein has been developed in an attempt to resolve the existing confusion and to offer a simplified approach to the study of a complex problem.

[The difference forms of "parapsoriasis en plaques". A report of 90 cases (author's transl)]. / Les différentes formes du parapsoriasis en plaques. A propos de 90 cas

The term parapsoriasis was used by Brocq (1902) to group a number of conditions previously described under different names. This group has since then been modified, the same conditions being described under separate names and these have led to a great confusion especially between countries. In this study of 90 cases, three types of parapsoriasis en plaques are distinguished. The "parapsoriasis digitiforme" (40 cases) or benign type, or xanthoerythrodermia perstans, or chronic superficial dermatitis is characterized by small, oval or finger-like, yellow or pink patches. The histology is frequently not characteristic, but in a few cases, there is an exocytosis localized "en flammèches" in the epidermis. The condition is usually permanent but none of these cases has progressed to mycosis fongoides. The parapsoriasis "en grandes plaques simples" (25 cases) is characterized by few pink patches (3 to 5), larger than in benign type. In our cases the transformation to poikiloderma atrophicans vasculare is not observed. One of these cases progressed to mycosis fongoides. The "parapsoriasis en grandes plaques poïkilodermiques" (25 cas), or poikiloderma atrophicans vasculare, prereticulotic poikiloderma, atrophic parapsoriasis, parapsoriasis lichenoides, is characterized by large patches, in limited number, showing a reticulated pigmentation and slight atrophy with telangiectasia. Five cases changed into mycosis fongoides and 4 cases showed some symptoms of malignancy; The histologic features are the same in the two last types: sometimes they are non-specific, in numerous cases the picture is characteristic with micro-abscesses or "flammèches"; in some cases there is a dense infiltrate with a clearly defined lower limit: this histologic appearance can be seen in cases without transformation into mycosis fongoides.