Proposed ICDRG Classification of the Clinical Presentation of Contact Allergy.

The International Contact Dermatitis Research Group proposes a classification for the clinical presentation of contact allergy. The classification is based primarily on the mode of clinical presentation. The categories are direct exposure/contact dermatitis, mimicking or exacerbation of preexisting eczema, multifactorial dermatitis including allergic contact dermatitis, by proxy, mimicking angioedema, airborne contact dermatitis, photo-induced contact dermatitis, systemic contact dermatitis, noneczematous contact dermatitis, contact urticaria, protein contact dermatitis, respiratory/mucosal symptoms, oral contact dermatitis, erythroderma/exfoliative dermatitis, minor forms of presentation, and extracutaneous manifestations.

Is reactive airways dysfunction syndrome a variant of occupational asthma?

BACKGROUND: Reactive airways dysfunction syndrome (RADS) or irritant-induced asthma is a syndrome that leaves subjects with asthma-like symptoms after one or more exposures to a high concentration of an irritant substance. The degree of reversibility of airway obstruction in subjects with RADS is nevertheless unknown, as is the degree of associated lesions at the airway level. METHODS: We compared the acute reversibility of forced expiratory volume in 1 second (FEV1) after inhalation of albuterol (200 micrograms) in 15 subjects with RADS (12 cases caused by chlorine inhalation) with that of 30 subjects with occupational asthma (OA) caused by various agents. They were paired according to baseline airway obstruction (61% and 63% of predicted value in the RADS and OA groups), requirement for medication (bronchodilator only--7 of 15 subjects with RADS and 14 of 30 subjects with OA--as compared with bronchodilator + inhaled steroids in 8 of 15 subjects with RADS and 16 of 30 subjects with OA, respectively), and interval since removal from exposure (means of 30 and 24 months in the RADS and OA groups). In addition, five nonsmokers with RADS who had not received inhaled steroids underwent bronchoscopy with lavage and bronchial biopsies less than 2 years after the exposure. RESULTS: The percentage increase in FEV1 over baseline after inhalation of albuterol was 10% +/- 9% in the RADS group and 19% +/- 16% in the OA group (p = 0.005). Only 2 of 15 subjects (13%) with RADS and 12 of 30 subjects (40%) with OA showed an improvement in FEV1 of 20% or greater after inhalation of albuterol. Bronchoalveolar lavage showed an increased number of cells with a predominance of lymphocytes, and biopsy specimens showed increased basement membrane thickness in the five subjects with RADS who underwent bronchoscopy. CONCLUSION: Subjects with RADS are generally left with less airway reversibility than those with OA. We suggest that this difference is secondary to distinct pathologic changes.

Clearance of Pseudomonas aeruginosa in different rat lung models.

Chronic pulmonary infections with Pseudomonas aeruginosa remain a serious problem in patients with cystic fibrosis. Structurally altered lung mucosa and local inflammation may impair bacterial clearance from the airways. This hypothesis was investigated in (1) the reserpinized rat, (2) proteinase-pretreated rat lungs, and (3) Type III hypersensitivity rat lung models. Reserpine treatment led to surface alterations of Type I epithelial lung cells and diminished food uptake. Significantly enhanced P. aeruginosa colony-forming units (CFU) were found in all (12 of 12) rat lungs 48 h after challenge compared to partially starved rats (p less than 0.025) or untreated rats (p less than 10(-6)). Pretreatment of normal rat lungs with elastase from polymorphonuclear leukocytes (PMN-elastase) resulted in extensive tissue damage, and 48 h after bacterial challenge the mean P. aeruginosa CFU of 12 animals was significantly higher 1.1 X 10(4) +/- 1.0 X 10(4) CFU; p less than 0.01) than in the reserpinized rat lungs. P. aeruginosa organisms were also found in PMN-elastase-treated rat lungs not challenged with bacteria (five of 12 animals), suggesting cross infection from infected animals in the same cage. In immunized rats that were challenged with aerosolized antigen (bovine serum albumin) and P. aeruginosa, bacterial CFU after 10 h were significantly higher than in nonimmune animals (p less than 0.005), and highest after 48 h when P. aeruginosa alkaline proteinase was used as the antigen (1.2 X 10(5) +/- 1.4 X 10(5) CFU). These data provide new evidence that clearance of P. aeruginosa from lung tissue is impaired after malnutrition, epithelial cell alteration, or epithelial cell damage.(ABSTRACT TRUNCATED AT 250 WORDS)

[The significance of immunologic phenomenons in pulmonary diseases of children (author's transl)]. / Die Bedeutung immunpathologischer Vorgänge für kindliche Lungenerkrankungen

Under special conditions the lung develops reactions of hypersensitivity, e.g. by the contact with antigens consisting of foreign proteins, organic dusts or different pathogen organisms. It must be distinguished between uncomplicated allergic and autoimmune diseases. The exact separation is difficult, because transitions from one state to the other are possible. The autoimmunisation is a very complicated phenomenon, where endogensou cells are effective as auto-antigens and induce the development of auto-antibodies. From the pathological-anatomical point of view thate are no typical structural changes in the lung, which define a disease as a special autoimmune disease. But the prevalence of round cells in inflamed tissue, the appearance of granuloma with epithelial cells point to immunological phenomenons. Examples for allergic diseases are: "Asthma bronchiale, pigeon-breeder disease, mite-allergy, farmer's lung, drug-induced allergy", and for autoimmune diseases: "Lupus erythematosus, rheumatoid arthritis, polyarteritis nodosa, idiopathic pulmonary hemosiderosis, idiopathic pulmonary fibrosis." The drug-therapy consists of corticoids and immune-suppressive drugs.