S. Lam

Occupational asthma in a technologist exposed to glutaraldehyde

BACKGROUNDnOccupational asthma can be caused by several sterilizing agents, including glutaraldehyde, which has been shown to cause irritation of the eyes and upper respiratory tract and skin rash. We report a case of occupational asthma that was caused by exposure to glutaraldehyde.nnnMETHODSnTo document the diagnosis of occupational asthma in a respiratory technologist, the following tests were performed: preshift and postshift spirometry, serial measurements of peak expiratory flow rate and nonspecific bronchial hyperresponsiveness, and workplace challenge test.nnnRESULTSnMonitoring of peak expiratory flow rate showed improvement when the subject was away from the workplace. Improvements in forced expiratory volume in 1 second (FEV1) and provocative concentration causing a 20% fall in FEV1 were also observed. A workplace challenge test showed a progressive fall in FEV1 when the subject was exposed to glutaraldehyde in a sterilizing agent used to clean bronchoscopes at her workplace. After the diagnosis of occupational asthma was confirmed, the subject continued to assist with bronchoscopy but no longer cleaned the bronchoscopes.nnnCONCLUSIONSnThis case study illustrates the usefulness of a workplace challenge test in confirming the diagnosis of occupational asthma. It also indicates the importance of preventing or reducing exposure to sterilizing agents such as glutaraldehyde by means of effective ventilation and proper storage and enclosure during use.

Immediate skin reactivity and its relationship to age, sex, smoking, and occupational exposure

To evaluate potential predictors of atopy, 3353 workers from various occupations were classified according to airborne exposures into three groups: (1) 1213 control workers with no measurable exposures, (2) 815 workers with gas and fume exposure, and (3) 1325 workers with organic dust exposure. Atopic status was determined by prick skin testing with common allergens. Workers exposed to organic dusts had a lower prevalence of skin test reactivity than either controls or gas- and fume-exposed workers. Skin test reactivity also decreased with age and was higher in nonwhite workers compared to white workers. No difference in skin test reactivity was seen between female and male workers, nor between smoking and nonsmoking workers. A logistic regression analysis that controlled for the correlation between the predictive factors confirmed the results of the crude analyses. It is suggested that atopic workers exposed to organic dusts might selectively leave the industry.

Predicting the response of obstructive endobronchial tumors to photodynamic therapy

To investigate the usefulness of bronchoscopic examination, computerized tomography (CT), and radio‐nuclide quantitative ventilation‐perfusion lung scan to determine the response of patients with obstructive endobronchial tumors to photodynamic therapy (PDT), the findings in 24 patients treated with PDT were analyzed. PDT was found to be most effective when the tumor was bronchoscopically polypoid in appearance, with little or no submucosal invasion or peribronchial extension seen on CT scans. With increasing submucosal and/or peribronchial extension, the immediate response to treatment was poorer. Patients who had 50% or more of the airway obstruction due to mucosal tumor had no evidence of local tumor recurrence for a median interval of 22 weeks after treatment. In patients with predominant submucosal and/or peribronchial tumor, the duration of response was 7 weeks. Response to treatment did not correlate with the degree of airway obstruction. CT provided valuable information regarding the extent of the peribronchial involvement and airway distortion, which was often underestimated by bronchoscopy alone. Absent perfusion or reduction of regional perfusion out of proportion to ventilation on scintigraphy in the involved lung zone was found to be associated with extensive peribronchial involvement and a poor outcome. The authors conclude that the addition of CT and radionuclide quantitative ventilation‐perfusion lung scan to bronchoscopic examination is useful in predicting the response of patients with obstructive endobronchial tumors to PDT.