Long-term respiratory disorders of claimers with subclinical exposure to chemical warfare agents

It is well documented that inhalation of sulfur mustard causes injury of the respiratory system. While all of the reports and surveys thoroughly document long-term pulmonary effects after significant exposure to mustard, there is no direct evidence that addresses the issue of long-term respiratory effects in individuals who were exposed to very low level of mustard and suffered no acute respiratory tract injury. Our subjects were selected among all those who were in chemically contaminated areas with chemical warfare agents (CWA) and had been registered for an annual checkup. Subclinical exposure's definition is the absence of any acute symptoms at the time of exposure. We used standard respiratory questionnaires, and chest HRCT examinations and a pulmonary function test were done. Based on exclusion criteria from total of 200 patients claiming respiratory problems, just 77 veterans entered the study. After performing HRCT for all our patients there were 13 (38.23%) veterans with no observable defect, 13 (38%) of them had just significant air trapping in their HRCTs. All the others had at least air trapping ( AT), which added to other defects. Septal wall thickening was seen in five veterans (14.7%) and bronchiectasis was seen in three (8.8%) cases. This study suggest that exposure to CWA was responsible for the occurrence of the bronchiolitis obliterans syndrome observed in our patients. There are many civilian and military people who have been present in contaminated area without signs and symptoms at the time of exposure, and early detection of such a population could be lifesaving.