Psoriasis and Lupus Erythematosus

The coincidence of LE and psoriasis seems to be rare. Based on their prevalence in the population, the coexistence of psoriasis with all forms of lupus seems to be less than expected. Dubois (Dubois 1974) reported that 0.6% of 520 patients with systemic LE (SLE) had concurrent psoriasis. Tumarkin et al. (Tumarkin et al. 1971) described 637 patients with discoid LE (DLE), and only 1 had coexistent psoriasis. In 1927, O'Leary (O'Leary 1927) described one of the first cases of coexistent psoriasis and LE. Throughout the years, several explanations concerning this coexistence have been developed. Schaumann (Schaumann 1928) postulated that the combination of LE and psoriasis - disorders with different "affinity" to the ground on which they appear - must be sought in the etiologic factors determining their pathogenesis. Louste et al. (Louste et al. 1939) focused on the "endocrine deficiency." Charpy et al. (Charpy et al. 1952) proposed that both disorders (in combination with arteriitis and hypertonia) be considered "disorders of adaptation." Kocsard (Kocsard 1974) considered the association of cutaneous LE and psoriasis vulgaris for a best explanation of the frequency of pseudopelade in patients with psoriasis. Millns and Muller (Millns and Muller 1980) think that LE and psoriasis could appear independently in the same patient without there being a causal relationship between the two disorders. Kulick et al. (Kulick et al. 1983) found that the frequency of antibodies to Ro/SSA is increased in patients with psoriasis and LE. They suggested that this might be a specific serologic marker for the LE-psoriasis overlap. It is well-known that the same antibodies occur in the antinuclear antibody (ANA)-negative, highly photosensitive group of patients with SLE. Accordingly, patients with psoriasis and LE may in fact have an increased risk for photosensitivity. Forty-three percent of all patients with SLE are photosensitive. On the contrary, the subset of "photosensitive psoriasis" is very small and comprises approximately 5.5% of all cases. These patients have a significantly higher prevalence of skin type I, and 50% have preceding polymorphous light eruption rising into psoriasis. Psoriasiform or annular lesions are also typical for patients with subacute cutaneous LE (SCLE). In such cases, histologic examina-

tion, immunofluorescence, and serology tests are necessary to distinguish SCLE from psoriasis.

Some of these patients, especially those with circulating anti-Ro/SSA antibodies, may be exclusively photosensitive. The action spectrum for LE is generally considered to be ultraviolet (UV)B, but some patients may flare after UVA exposures received in tanning salons or from sunlight filtered through window glass.

The control of SLE often requires systemic administration of steroids, especially for renal and central nervous system involvement. A rebound flare of psoriasis is always possible on withdrawal of steroid therapy. Administration of antimetabolites used as steroid-sparing agents may prevent this rebound flare and improve psoriasis. Phototherapy is contraindicated in patients with cutaneous LE. On the contrary, pso-ralen-UVA exposure is indicated in psoriatic individuals and in those with severe "photosensitive psoriasis." Screening for ANAs, including anti-Ro/SSA and anti-La/SSB antibodies, is necessary before treating any photosensitive patient with UV light. Psoriasis could coexist with other photosensitive disorders, such as vitiligo, por-phyria, drug-induced photodermatitis, polymorphous light eruption, chronic actinic dermatitis, solar urticaria, actinic prurigo, and the so-called "fair skin type".

Some psoriasis patients develop LE (subacute cutaneous, chronic cutaneous, or systemic) after psoralen-UVA therapy (Dowdy et al. 1989). Zalla and Muller (Zalla and Muller 1996) studied 9420 patients with psoriasis, and 65 (0.69%) had concomitant photosensitive disorders. Of these, 23 (35%) had psoriasis and nonlupus-related photosensitivity and 42 (65%) had psoriasis and LE with or without photosensitivity. The conclusion is that the coexistence of psoriasis with LE or other photosensitive disorders is rare. These studies may explain the coexistence of LE in patients with psoriasis after UV therapy. However, this possibility does not help explain the coexistence of LE in patients with psoriasis who have not had significant exposure to UV light or in those in whom LE develops before the onset of psoriasis. The explanation probably resides in the multifactorial etiology of both diseases. The hypothesis that patients with LE and psoriasis have common serologic markers (anti-Ro/SSA antibodies) is not convincing (Baselga et al. 1994, Hays et al. 1984, Kobayashi et al. 1995, Kulick et al. 1983). Both disorders may appear independently in the same patient with no causal relationship between them (Millns and Muller 1980, Wlashev et al. 1986).

Antimalarials are now the drugs of choice for treatment of the cutaneous and joint manifestations of LE. It is well known that the use of chloroquine and hydroxychloroquine may aggravate or precipitate psoriasis (Nicolas et al. 1988). We suggest that in patients treated with antimalarials in which LE precedes the development of psoriasis, drug-induced psoriasis could be possible (Tsankov et al. 1990). Large-scale prospective studies of the general population for the coexistence of diseases such as LE and psoriasis aim at the same scientific goal: elucidation of the etiology and prescription of the the most appropriate therapy (Rongioletti et al. 1990a).

Natural Treatments For Psoriasis

Natural Treatments For Psoriasis

Do You Suffer From the Itching and Scaling of Psoriasis? Or the Chronic Agony of Psoriatic Arthritis? If so you are not ALONE! A whopping three percent of the world’s populations suffer from either condition! An incredible 56 million working hours are lost every year by psoriasis sufferers according to the National Psoriasis Foundation.

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