Hemophilus influenzae biotypes and chronic bronchitis.

Hemophilus influenzae can be differentiated into 6 biotypes on the basis of 3 biochemical reactions. This study was undertaken to determine the biotypes of respiratory isolates from an adult population with chronic bronchitis and to compare the biotypes of upper and lower respiratory tract isolates of individual patients. For rapid biotyping of serologically nontypable H. influenzae, we used 2 commercially prepared kits (Minitek and IDS RapID Systems). Twenty-three of 29 isolates (79%) had biochemical characteristics of biotype II with the Minitek system. Eighteen of the same 29 isolates were retested with the IDS RapID System and reacted as biotype II organisms. Seven of 9 and 4 of 4 paired transtracheal/oropharyngeal samples had identical biotypes when tested with the Minitek and IDS RapID System, respectively. These findings suggest that H. influenzae organisms are exchanged between the oropharynx and tracheobronchial tree of elderly male patients with chronic bronchitis.