A case of severe psoriasis with an apparent incomplete response to anti-tumour necrosis factor alpha treatment

This report covers a case of severe psoriasis that appeared to respond well to treatment with subcutaneous etanercept, with good recovery of the arthropathic component. However, there were distinct areas at the patient's hands and wrists that failed to respond to such treatment. A standard series of patch tests yielded strong positive responses to the vaseline ointment and mercaptobenzothiazole mix, substances that the patient had constantly applied, twice daily, before and during the anti-tumour necrosis factor alpha therapy course, as an emollient, rubber-gloved topical treatment. This case is reported to provide further evidence of the efficacy of etanercept treatment, and to confirm that the immunopathological pathway leading to psoriasis and allergic contact dermatitis (ACD) sometimes goes into 'overdrive' in ACD, giving a mixed pattern, involving each of the branches of the immune system.