Effect of Plastic Occlusive Dressings on Psoriatic Epidermis

Abstract

SUMMARY.— Serial biopsies have been performed on psoriatic lesions from the forearm in 13 patients in whom the lesions were occluded with plastic occlusive dressings for 2 weeks, and in 13 control psoriatic subjects. A complete granular layer was not present in the occluded or control lesions prior td the study. In the occluded lesions a complete layer developed in 25 of the subsequent 65 biopsies but in only 2 of the 65 biopsies in the control group. In 10 of the 13 subjects the occluded lesions showed a complete granular layer at some stage during occlusion, although the time when it first appeared was variable. In 4 of these 10 patients the granular layer became incomplete after reformation during the period of study. Mitotic counts of the occluded psoriatic lesions showed a slight but significant fall at the end of the 2‐week period but this did not occur in the control lesions. There was no significant depression of the mitotic count at the time when the granular layer first reformed. It is suggested that plastic occlusive dressings have some effect on psoriasis, and possible mechanisms of action are discussed.

The Immunohistochemical Effect of a Hydrocolloid Occlusive Dressing (DuoDERM E) in Psoriasis vulgaris

“…Baxter and Stoughton [1] reported that an occlusive dressing applied on lesions for 23 or 24 h each day for 4 days decreases the mitotic index. This was confirmed by Fry et al [2], who also found restoration of the granular cell layers after treatment of psoriasis with plastic occlusive dressings for 2 weeks. Shore [3] demonstrated that most plaques either improved or resolved, and some remained clear for a month or more after treatment with occlusive tape.…”

“…Fry et al [2] reported two decades ago that plastic occlusion, applied during a 2-weck period, improves pso riatic plaques whilst causing a fall of mitotic counts in the epidermis. Following a 2-week treatment period with the HCD DuoDERM .…”

Response of Psoriatic Lesions to Multiple Applications of Leukotriene B₄ and 12-HETE

“…The general trend towards resolution of the psoriatic lesions both at test and control sites may reflect inhibition of epidermal mi totic activity, which is known to occur fol lowing occlusion of psoriasis by synthet ic semipermeable or occlusive coverings [15][16][17], The mechanism underlying this phenomenon, which to our knowledge has not been documented previously with a re gime of intermittent occlusion, is unclear. It is possible that improvement in the lesions induced by occlusion masked a specific effect of LTB4 or 12-HETE.…”

Flow Cytometric Assessment of Clearance and Relapse Characteristics in Psoriasis vulgaris after Treatment with Weekly Clobetasol Lotion under Hydrocolloid Occlusion versus Twice-Daily Clobetasol Ointment

“…In some of these patients DNA synthesis was also totally suppressed in the uninvolved skin. As Baxter and Stoughton [15] and Fry et al [16] both observed a decreased mitotic index in psoriatic lesions after treatment with occlusive dressings without adjunct treatment, the reduced proliferative activity probably is not exclusively the result of the application of corticosteroids. The present study, showing the relatively fast clearance in the lesions treated with the combination of clobetasol lotion and HCD compared to the lesions treated with clobetasol ointment monotherapy illustrates the additional value of HCD in treating psoriasis.…”