LATENT ADENOVIRAL INFECTION IN FOLLICULAR BRONCHIECTASIS

The follicular form of bronchiectasis originally described by Whitwell (1) has been associated with adenoviral infection. The present study compares resected lungs from 16 patients with follicular bronchiectasi s (in 10 of whom a nonviral etiology was identified) with those from e ight patients with a nonfollicular histologic pattern. DNA isolated fr om sections of 45 paraffin-embedded lung samples was subjected to the polymerase chain reaction (PCR) using primers for the E1A region of th e adenovirus genome and the human HLA DQ alpha gene. In situ hybridiza tion (ISH) was performed on separate sections cut from the same blocks using a probe for the entire adenovirus 5 genome. E1A was demonstrate d in six of eight patients (75%) with nonfollicular bronchiectasis (no n-FB) and in four of 16(25%) with follicular bronchiectasis (FB) (p < 0.03, Fisher's exact test). The optical density ratio for the E1A prod uct of PCR (ratio of E1A product from specimen to that from 1 pg adeno virus DNA) was significantly lower in FB than in non-FB (0.057 +/- 0.0 54 versus 0.365 +/- 0.223 [mean +/- SEM], p < 0.05). Moreover, the dur ation of symptoms of bronchiectasis in patients without E1A in bronchi al specimens was significantly shorter than that of patients with posi tive E1A PCR products (3.09 +/- 1.44 versus 14.41 +/- 3.33 yr; p < 0.0 5). By ISH, adenovirus was demonstrated in three patients with FB and in two with non-FB (17.2 and 18.8% of tissue blocks, respectively; NS) . These findings represent a lower prevalence of latent adenovirus tha n that found in smokers with normal lung function, and they fail to su pport a causal link between adenovirus infections (latent or lytic) an d bronchiectasis at this late state of disease. This suggests that the bronchial mucosal defenses mounted during the development of bronchie ctasis may eliminate the adenovirus found in the majority of adult lun gs.