Document 44zmBX1Nye1nZ5N1R7LEJkV5V

IJMS Journal Autunm 2003 23/2/04 2:53 pm Page 155 correspondence Reactive airway dysfunction syndrome in Ireland Dear Editor, Reactive airway dysfunction syndrome (RADS) is a form of asthma first described by Brooks et al.1 Original criteria for RADS diagnosis included no preceding respiratory disease, symptoms occurring following single exposure, inhalation of concentrated irritant smoke or fumes, cough, wheeze and breathlessness, function tests featuring airflow obstruction and positive methacholine challenge. We describe seven cases of RADS encountered since our original report of the first case of RADS in Ireland.2 We include four cases featuring new irritants not previously reported. A 32-year-old male trucker (see Table 1, case 1) loaded drums containing ethanol, isopropanyl and gingerine. A drum valve leaked and he detected an acrid smell while closing the valve. Immediately he felt unwell with chest pain, wheeze and breathlessness. A diagnosis of asthma was made. Sixteen months later, he remained on anti-asthma medications and still had chest discomfort and wheeze. Pulmonary function tests showed classical asthma patterns. A 41-year-old male (see Table 1, case 2) had an acute inhalation injury, after exposure to a liquid (proprionic acid, ammonium hydroxide and sorbic acid) sprayed on fishprocessing machines. He developed a cough and chest tightness. His doctor prescribed anti-asthma medication. His symptoms were exacerbated by exposure to fumes, hay, dust and smoke. Function tests revealed typical reversible airflow obstruction. Since Brooks' original description, more cases have been described in various settings.3 Our present cases extend the spectrum of causes of RADS to exposure to: (a) ethanol, isopropanyl and gingerine; (b) proprionic acid, NH4 and sorbic acid; (c) burning rubber; and (d) sewerage gas. It confirms that most spillages occur indoors where toxic inhalation is concentrated. All of our patients had symptoms over a follow-up period of 17.6 months (range 6-36 months) suggesting longterm persistence of RADS. This and the low group mean age (41 years) has significant socioeconomic and vocational ramifications. RADS induction is attributable to acute airway inflammation provoked by non-sensitising chemicals. Brooks has suggested that inflammation may persist long term, given the intensity of the respiratory inflammation and subsequent dysregulated re-epithelisation and re-innervation. It must be emphasised that such accidents are preventable by appropriate industrial hygiene and better respiratory protection. AM McLaughlin, E MC Kone, MX Fitzgerald Department of Medicine and Therapeutics, St Vincent's University Hospital, Elm Park, Dublin. Email:muiris.fitzgerald@ucd.ie References 1. Brooks SM, Weiss MA, Bernstein IL. Reactive airway dysfunction syndrome (RADS): persistent asthma syndrome after high level irritant exposures. Chest 1985; 88: 376-84. 2. Donnelly SC, FitzGerald MX. Reactive airway dysfunction syndrome due to chlorine gas exposure. Ir J Med Sci 1990; 159: 275-7. 3. Gautrin D, Bernstein I, Brooks S. Reactive airways dysfunction syndrome, or irritant-induced asthma. Asthma in the workplace. (2nd edition). Eds Bernstein I, ChangYeung M, Malo J, Bernstein D. Marcel Dekker, Inc, New York, Basel 1999; 65-593. Table 1. Presentation of seven cases of RADS Age & Sex Exposure Asthma symptoms therapy Peak flow (l/min) FEV1 (l) FVC (l) 32m Ethanol, Yes isopropanyl & gingerine# 41m Proprionic acid, Yes NH4 & sorbic acid 39m Rubber fumes Yes 64f Sewerage gas Yes 39m Ammonia Yes 43m Chlorine Yes 31m Chlorine# Yes + + + + + + + #Exposure occurred outdoors. * Pulmonary function indices after bronchodilators Irish Journal of Medical Science Volume 172 Number 3 550/620* 3.95/4.65* 5.1/5.45* 490/620* 4.5/4.7* 5.3/5.7* 570/600* 190/200* 350/650* 485/560* 695/710* 2.9/3.2* 0.9/1.1* 3.5/3.7* 4.0/4.4* 4.7/5.2* 3.5/3.7* 1.4/1.7* 2.9/3.2* 4.2/4.95* 6.3/6.6* 155