Oral hyposensitization in Parthenium dermatitis

Parthenium the terminator: An update

Parthenium dermatitis is a distressing dermatitis caused by the air borne allergen of the Compositae weed Parthenium hysterophorus. Uncommon presentations, newer insights in pathogenesis and management of this "scourge" are discussed in this article.

Immunotherapy of allergic contact dermatitis

The term 'immunotherapy' refers to treating diseases by inducing, enhancing or suppressing immune responses. As allergy is an excessive, detrimental immune reaction to otherwise harmless environmental substances, immunotherapy of allergic disease is aimed at the induction of tolerance toward sensitizing antigens. This article focuses on the historical developments, present state and future outlook for immunotherapy with haptens as a therapeutic modality for allergic contact dermatitis. Inspired by the effectiveness of immunotherapy in respiratory allergies, attempts were undertaken at curing allergic contact dermatitis by means of controlled administration of the sensitizing haptens. Animal and human experiments confirmed that tolerance to haptens can be induced most effectively when the induction of tolerance precedes attempted sensitization. In real life, however, therapy is sought by people who are already sensitized and an effective reversal of hypersensitivity seems more difficult to achieve. Decades of research on Rhus hypersensitivity led to a conclusion that immunotherapy can suppress Rhus dermatitis, however, only to a limited degree, for a short period of time, and at a high risk of side effects, which makes this method therapeutically unprofitable. Methodological problems with most available studies of immunotherapy of contact allergy to nickel make any definite conclusions impossible at this stage.

Airborne contact dermatitis - current perspectives in etiopathogenesis and management

The increasing recognition of occupational origin of airborne contact dermatitis has brought the focus on the variety of irritants, which can present with this typical morphological picture. At the same time, airborne allergic contact dermatitis secondary to plant antigens, especially to Compositae family, continues to be rampant in many parts of the world, especially in the Indian subcontinent. The recognition of the contactant may be difficult to ascertain and the treatment may be even more difficult. The present review focuses on the epidemiological, clinical and therapeutic issues in airborne contact dermatitis.

Oral hyposensitization in patients with contact dermatitis from Parthenium hysterophorus

Parthenium hysterophorus is the commonest cause of airborne contact dermatitis in northern India. Treatment is mostly palliative and consists of repeated courses of antihistamines and topical and/or systemic corticosteroids. We have evaluated the effect of oral hyposensitization as an alternative therapeutic modality. In 70% of those patients who completed the study, there was a gradual improvement in their clinical status, as evident from a fall in their clinical severity score for eczema. 30% of patients had an exacerbation during the course of the study and hence hyposensitization in them was stopped. Patients tolerated therapy well and no significant side-effects were seen, except for abdominal pain, 'heartburn' and cheilitis.

Compositae dermatitis: a survey

Compositae dermatitis in an allergic contact dermatitis, frequently chronic, triggered by plants of the Compositae family. The condition, which is seen, in particular, in middle-aged and elderly persons, typically starts in the summer months with an acute eczema either corresponding to areas exposed to light and air, or corresponding to areas of plant contact; it disappears spontaneously during the fall of the year. Repeated exposure over a number of years may cause severe intractable dermatitis affecting the patient throughout the year. The responsible allergens are sesquiterpene lactones, and investigations to date indicate that the frequency of the allergy is similar to that seen with some of the contact allergens of the standard patch test series. The diagnosis, however, is difficult, partly due to the fact that the clinical picture may be mistaken for a photodermatosis, and partly owing to the difficulty in obtaining commercially available allergens for patch testing. The diagnosis is therefore based on testing with plant extracts, which can cause pronounced local reactions and possibly active sensitization. A survey is given of the possible modes of sensitization, sex and age distribution, the relationship to photosensitivity and atopy, as well as the possible treatment. It is concluded, on the basis of the chronic nature of the disease, and the diagnostic and treatment problems, that continued intensive research into the condition is urgently needed.

Airborne contact dermatitis: an update

This review is an update of a previously published one on airborne-induced contact dermatoses. Because reports in the literature often omit the term 'airborne', 12 volumes of Contact Dermatitis (July 1985-April 1991) were screened, and the cases cited were classified as to history, lesion locations, causative agents, and other factors. The number of reports of airborne dermatoses has increased considerably in recent years.