Medline ® Abstracts for References 20,45
of 'Reactive airways dysfunction syndrome and irritant-induced asthma'
Outbreak of the reactive airways dysfunction syndrome after a spill of glacial acetic acid.
Am Rev Respir Dis. 1991;144(5):1058.
The reactive airways dysfunction syndrome (RADS) defines a chronic asthmalike illness with airway hyperresponsiveness that develops within 24 h of a single, brief, highly irritating inhalation exposure. Support for the syndrome has been limited to case reports. A chemical spill, exposing hospital employees to 100% acetic acid, offered an opportunity to more convincingly establish the existence of RADS. All 56 exposed subjects were asked both to complete a questionnaire focusing on their preexposure health status, potential for exposure, and symptom development after the accident, 8 months after the spill, and to undergo methacholine challenge testing to detect airway hyperresponsiveness. An industrial hygienist, blinded to clinical data, estimated each subject's exposure. Preemployment health history forms were reviewed to assess recall bias. The study questionnaire was returned by 51 (91%) subjects; 24 (47%) consented to methacholine challenge, including 7 of the 8 with RADS-consistent symptoms. Diagnostic criteria for RADS were satisfied by none of 7 (0%) subjects with low exposure, 1 of 30 (3.3%) with medium exposure, and 3 of 14 (21.4%) with high exposure (test of trend p value = 0.021). The odds ratio estimate of the relative risk of RADS in subjects with high exposure was 9.8 (95% Cl, 0.902 to 264.6). Neither stratified analysis nor review of the preemployment health history forms revealed evidence of confounding or recall bias, respectively. The reactive airways dysfunction syndrome appears to be a valid clinical entity. Further study of RADS is especially appropriate given increasing evidence that airway inflammation may be etiologically important in all asthma.
Department of Medicine, Memorial Hospital of Rhode Island, Pawtucket 02860.
Persistent respiratory health effects after a metam sodium pesticide spill.
Cone JE, Wugofski L, Balmes JR, Das R, Bowler R, Alexeeff G, Shusterman D
STUDY OBJECTIVE: To report the occurrence of persistent respiratory disorders, including irritant-induced asthma, among adults living and working near an environmental spill of the pesticide, metam sodium, after the derailment of a tank car.
DESIGN: Retrospective clinical case series.
SETTING: California communities situated within one-half mile of the Sacramento River, from Mt. Shasta City to Shasta Lake.
PATIENTS: 197 adults referred to a university occupational/environmental health clinic or to a private occupational/environmental health practitioner for evaluation of health problems potentially related to the spill.
MEASUREMENTS AND RESULTS: History, physical examination, review of medical records, spirometry, and methacholine challenge testing revealed 20 cases of persistent irritant-induced asthma and 10 cases of persistent exacerbation of asthma.
CONCLUSIONS: This is the first reported series of cases of persistent irritant-induced asthma involving both community residents and occupationally exposed individuals.
Department of Medicine, University of California, San Francisco, USA.