“…There is a broad range of agents that have been reported as known or suspected causes of either chronic bronchitis, bronchiolitis, BO disease, and/or similar small airways disease in humans, as illustrated for environmental exposures and disease states in Table 2 [3] , [5] , [8] , [10] , [12] , [52] , [56] , [68] , [73] , [79] , [85] , [87] , [97] , [106] , [110] . With respect to pharmaceutical or iatrogenic associations (see Table 3 ), most cases of BO disease are linked to heart/lung and bone marrow transplants and autoimmune connective tissue disease risk factors listed in Table 3 , with the infectious agents more prominently affecting young children [12] , [17] , [79] .…”