24 research outputs found
Evaluation of impermeable covers for bedding in patients with allergic rhinitis
BACKGROUND: Encasing bedding in impermeable covers reduces exposure to
house-dust mites, but the clinical benefit of this intervention as part of
mite-avoidance measures for patients with allergic rhinitis is not known.
We performed a multicenter, randomized, placebo-controlled trial of one
year of use of impermeable bedding covers in the bedrooms of patients with
rhinitis who were sensitized to house-dust mites to determine the effects
on the signs and symptoms of disease. METHODS: Three participating
university medical centers enrolled 279 patients with allergic rhinitis
who were randomly assigned to receive impermeable or non-impermeable
(control) covers for their mattress, pillow, and duvet or blanket. At the
start of the study, all participants received information on general
allergen-avoidance measures. The severity of rhinitis was measured on a
rhinitis-specific visual-analogue scale and by means of a daily symptom
score and nasal allergen provocation testing. We also measured the
concentrations of Dermatophagoides pteronyssinus (Der p1) and D. farinae
(Der f1) in dust from patients' mattresses, bedroom floors, and
living-room floors at base line and after 12 months as a measure of the
efficacy of the intervention. RESULTS: A total
The clinical spectrum of humidifier disease in synthetic fiber plants
In a synthetic fiber production site with recirculating cold water humidification systems and small-size-particle (> 0.1 mu <1 mu) oil mist exposure, humidifier disease was diagnosed in several workers. The patients could be divided into three groups illustrating the clinical spectrum of humidifier disease: humidifier fever (toxic inhalation fever) (12 patients); an asthma-like syndrome (8 patients); and allergic alveolitis (4 patients). Natural challenge at the work place, monitored by parameters such as peak-flow, spirometry, blood leucocyte count, and body temperature, provided important diagnostic information. In patients with chronic allergic alveolitis, a gradual recovery during an exposure-free period indicated a work-related causation, more than changes during challenge in normal work. In some patients, the fungus Sporothrix schenckii, hitherto unknown as a sensitizer, may have been at least one of the causative antigens. Measured levels of viable fungi (less than or equal to 100 CFU/m(3)) and endotoxin (64 pg/m(3)) in air samples were much lower than those at which health effects usually are reported. Small-size-particle oil mist exposure may have underestimated the exposure to microorganisms, but otherwise an adjuvant role to this type of co-exposure might also be postulated. In contrast to allergic alveolitis, the asthma-like syndrome appeared to be more common in patients with a history of atopy and of smoking. (C) 1997 Wiley-Liss, Inc
Follow-up study of workers in a nylon carpet yarn plant after medical remedial actions taken against a contaminated humidification system
Follow-up study of workers in a nylon carpet yarn plant after medical remedial actions taken against a contaminated humidification system
The effect of gas cooking on bronchial hyperresponsiveness and the role of immunoglobulin E
Assessment of exposure to wheat flour and the shape of its relationship with specific sensitization
Objectives Dust and wheat-allergen exposure were assessed among bakers, flour millers, and bakery-ingredient producers, and the risk for sensitization was studied. Methods About 520 inhalable dust and wheat-allergen measurements were made among 270 Dutch workers. Data on sensitization to wheat and common allergens (atopy) were also available. Exposure was estimated according to the sector of industry, job title, and tasks. The shape of the relationship between sensitization and exposure was studied using a two-stage modeling approach: semi-parametric generalized additive modeling and, consequently, a simple description of the relationship using a parametric logistic model. To reduce the effect of exposure measurement errors (attenuation), a combination of the actual measured exposure and variance-weighted estimates of exposure was used. Results The effect of exposure to both inhalable dust and wheat allergens on sensitization was described best by a linear relationship in three industries and a quadratic relationship in one industry. The relation for the whole study population was best described as quadratic, and the probability of sensitization increased with exposure up to ~2.7 mg/m3 for inhalable dust and ~25.7 µg EQ/m3 for wheat allergens. The risk decreased at higher exposures (P=0.0121 and P=0.0731 for dust and wheat, respectively). Atopy and sector of industry modified the sensitization risk significantly in all the analyses. Using a variant-weighted estimator to calculate exposures corrected for the bias and resulted in almost the same point risk estimators. Conclusions Exposure–response relationships for allergens may be nonlinear and differ between industries. A threshold is not indicated on which to base occupational exposure standards; alternatively, other approaches, such as benchmarking, seem warranted