The relationship between pulmonary interstitial emphysema and clinical features in fatal asthma

Using retrospective histological material and clinical data from the New Zealand National Asthma Mortality Study, we investigated whether there was a relationship between the presence of pulmonary interstitial emphysema (PIE) and different clinical features in fatal asthma, in particular precipitous asthma death. Histological evidence of PIE was determined in sections from 12 of the 60 patients who had died from asthma who fulfilled the pathological criteria for inclusion in the study. No significant correlation was found between the presence of PIE and the different clinical features examined. For example, of the 13 cases with precipitous fatal asthma (i.e., death occurred within 10 min of the onset of the attack), only two had PIE. This suggests that PIE is not an uncommon histological feature of fatal asthma and may, in fact, significantly contribute to an asthma death, but its presence does not appear to be associated with the specific clinical subgroups studied here.