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Notes: Leukotriene B4 (LTB4) receptor antagonists have been the subject of several studies in the treatment of inflammatory diseases, including psoriasis. A novel oral LTB4 antagonist, VML 295 (LY-293111) has recently been developed and has a pronounced effect on epidermal inflammatory parameters. However, oral treatment of psoriasis for 4 weeks did not result in a decrease in disease severity. The present study was performed in order to investigate whether prolonged treatment with VML 295 up to 8 weeks has a beneficial effect on the overall severity of psoriasis. Moreover, we studied to what extent VML 295 is able to prevent relapse in psoriasis. In the present study, 35 patients with stable chronic plaque psoriasis were included. A representative plaque of at least 16 cm2 was initially treated with clobetasol-17-propionate lotion under hydrocolloid occlusion in all patients. Clearance was achieved within 6 weeks in 31 patients. After clearance, the patients were randomized to treatment and received oral VML 295 capsules 200 mg twice daily or placebo for 8 weeks. Twenty-five patients completed the study. The psoriasis area and severity index (PASI) was assessed before treatment, at clearance, and on days 15, 29, 43 and 57 of the treatment period. Biopsies were taken from the treated lesion before treatment, after clearance and at relapse, and cells were analysed by flow cytometry with markers for differentiation (keratin 10), inflammation (vimentin), and proliferation (DNA content). After 8 weeks of treatment, 14 of 15 VML 295-treated patients had relapsed and 11 of 16 placebo-treated patients had relapsed. A total of six patients were withdrawn. The time to relapse and the number of relapsed patients was not significantly different comparing the treatment groups. There was no significant difference in PASI scores between VML 295-treated patients and placebo-treated patients after 8 weeks of treatment. Flow cytometric parameters for differentiation, inflammation and proliferation did not show significant differences between VML 295- and placebo-treated patients. We conclude that oral VML 295 (LY-293111) is not effective in preventing relapse in psoriasis, either clinically or at the cellular level, and that in our group of patients VML 295 had no beneficial effect on overall psoriasis severity. Moreover, we conclude that further development of LTB4 modulating drugs for the treatment of psoriasis is not indicated.

Notes: Liarozole, a novel imidazole derivative, inhibits the cytochrome P450-dependent 4-hydroxylation of retinoic acid. resulting in increased tissue levels of retinoic acid. Twelsve male patients with ichthyosis were given oral liarozole. 150mg twice daily. in an open study for 12 weeks. Immunohistochemical parameters of inflammation, epidermal proliferation and differentiation were assessed before and after treatment. Extent and severity of the skin lesions was markedly reduced in all prtients. Clinical side-effects were reminiscent of those with synthetic retinoids. No relevant changes were found in the haematological. urinary and biochemical parameters. Immunohistochemical assessment showed a statistically significant induction of keratin 4 after liarozole treatment in 10 of 12 patients. In two of these patients keratin 13 was induced. This open study showed that oral liarozole treatment was efficacious and well tolerated in the treatment of different types of ichthyosis. The immunohisotchemical results suggest a retinoid mechanism as the mode of action.

Notes: Toxic Pustuloderma is an acute pustular eruption of the skin occurring a few days after the initiation of treatment with the responsible drug. A case of toxic pstuloderma following treatment with the antihistamine clemastine is now reported.

Notes: Platelet-activating factor (PAF) is considered to be one of the most potent lipid mediators in allergic and inflammatory reactions. Suggestions that PAF is produced by cutaneous cells, and cells infiltrating the skin from the blood, have been reported. PAF has been identified in allergic cutaneous reactions and also in psoriatic lesions. The biological activity of PAF is thought to be mediated by cell membrane receptors.Studies revealed that PAF-antagonists can be active in animal models of cutaneous inflammation. In humans PAF-antagonists showed minimal therapeutic improvement in studies of antigen-induced cutaneous responses in atopic subjects. No data are available on the effects of PAF-antagonists in psoriasis.The objective of this study was to investigate the effect of a potent PAF-antagonist (Ro 24–0238, 10% solution in diethylene glycol monocthyl ether) in 10 patients with chronic plaque psoriasis, a placebo-controlled double-blind study. Clinical response was evaluated and markers of inflammation, differentiation and proliferation were studied immunohistochemically on punch biopsies taken from actively treated and placebo-treated lesions, before and after treatment.This study demonstrated that a 10% solution of the PAF-antagonist Ro 24–0238 was not effective at the clinical or cell biological level after a 4-week treatment period. The most likely explanation for these negative observations is that PAF is not a significant factor in the pathogenesis of psoriasis.

Notes: Cumulative toxicity is a well known limitation of antipsoriatic treatments. In particular, the induction of multiple squamous cell carcinomas following long–term PUVA treatment is well established. In the present report, a psoriatic patient is described who was treated for more than 14 years with photochemotherapy (PUVA) and who received excessive amounts of topical corticosteroids.The patient developed, in total, 34 squamous cell carcinomas. In all, three squamous cell carcinomas developed during long–term PUVA treatment, and 21 carcinomas appeared during 16 months of treatment with cyclosporin. Subsequently, a marked inhibition of the occurrence of new tumours occurred during prolonged treatment with acitretin, and no new tumours have appeared during the last 4 years of continuous treatment with this retinoid at a dose of 60mg/day.Modulation of the expression of PUVA–induced squamous cell carcinomas by cyclosporin and acitretin are discussed. The present report lends support to the hypothesis that cyclosporin causes an increased occurrence of PUVA–induced carcinomas, whereas acitretin (60mg/day) is of value in preventing the occurrence of new squamous cell carcinomas in patients who were treated with long–term PUVA.

Notes: Numerous investigations have been carried out to describe the cellular biological changes in lesional and symptomless psoriatic ski. Although these studies have increased our knowledge of the pathogenesis of psoriasis, our insight into the relevance of the individual changes in the whole pathogenic process is still limited. Studies on the transition between symptomless and lesional skin are of importance in assessing the pathogenic relevance of the individual aspects. In this paper, the literature is reviewed with respect to the transitional changes; in particular, studies on changes at the margin of the psoriatic lesion and the response of the symptomless skin to standardized injury are reviewed. From the available studies it may be concluded that changes in the stroma (i.e. increased expression of tenascin and increased endothelial alkaline phosphatase activity) are early pathogenic features. The appearance of a predominantly lymphocytic infiltrate, in particular the extravasation of CD4+ T lymphocytes, and the suprabasal expression of keratin 16 are intermediary stages. Relatively late in the pathogenesis are increased recruitment of cycling epidermal nuclei, parakeratosis, decreased expression of filaggrin and premature expression of involucrin. In order to discover the pathogenic relevance of molecules which might have an impact on the development of psoriasis, sequential studies during transition from symptomless to lesional skin are worthwhile.

Notes: Knowledge of the physiology of wound healing, in particular the recovery of the dermal and epidermal compartments and the co-ordination of these processes by the cytokine network, is of great importance to rational wound management. The individual components of the wound healing process have been studied using various in vttro and in vivo models, comparing young, adult and aged individuals. Many ofthc processes involved in wound healing are impaired in the elderly. However, in elderly patients not suffering from concomitant diseases, the rate of wound healing is normal or (tnly slightly reduced. Various ‘systemic factors’ (endocrine and haematolugical diseases, nutritional deficiencies and medications) and ‘regional disorders’ (vascular and neural diseases) ma impair wound healing. These complicating conditions occur more frequently in aged subjects. Failure of wound healing in the elderly is a chronic disabling condition, which occurs frequently in our society, requiring a major investment of medical care.

Notes: Background Controversy still exists as lo whether a dosage scheme for the treatment of severe psoriasis with cyclosporin A (CsA) should start with low dosages (3 mg/kg/day) or rather with high dosages (5 mg/kg/day).Aims In this open prospective multi-centre trial guidelines for the use of CsA in psoriasis beginning with low dosages were evaluated. A secondary aim of the study was to elucidate factors predicting efficacy of CsA treatment.Methods Efficacy and tolerability of CsA were evaluated monthly during 16 weeks in 86 patients (56 males, 30 females, mean age 43,0 ± 14,9 years) suffering from chronic severe plaque-type psoriasis, not responding to topical therapy (mean PASI 18.0 ± 8.1). All patients started with 3 mg/kg/day. Patients were defined as responders with a PASI reduction 〉 25% at month 1, ≥ 25% at month 1, ≥ 60% at month 3 and ≥ 70% at month 4. When a patient was a failure, the dose was increased by 1 mg/kg/day lo a maximum of 5 mg/kg/day.Results A gradual mean PASI reduction of 38%. 59%, 72% to 76% was reached with a mean CsA dose of 3.0, 3.2, 3.5, and 3.6 mg/kg/day at weeks 4, 8, 12 and 16. respectively. At the end of the study period, 39 patients were still on 3, 24 patients were on 4 and 15 patients were on 5 mg/kg/day. Due to subjective side-effects 6 patients dropped out on 3 mg/kg/day and 2 on 4 mg/kg/day. Diastolic and systolic blood pressure and creatinine levels were stable. Overall, CsA was relatively well tolerated. Absence of previous therapies, low baseline PASI and failure at week 4 were predictive for higher drop-out and failure rate and lower PASI at the end of study.Conclusions This study shows that a significant proportion of severe psoriasis patients can be treated with 3 mg/kg/day CsA with good tolerability and excellent clinical results. It is concluded that a treatment scheme with an optimal risk-benefit ratio should start with low dosages of CsA (3 mg/kg/day).