Transmission of nonfermenting gram-negative bacilli by multiple-dose inhalers.

The description by Cheron et al. (1) of an outbreak of hospital-acquired infections due toAlcaligenes denitnfi cans and other nonfermenting gram-negative bacilli was reminiscent of a similar outbreak at our hospital. During a 1-month period there were 11 cases of mixed bacterial infections involving Acinetobacter anitratus, Flavobacterium meningosepticum, and Xanthomonas maltophila in our 15-bed intensive care unit. Tracheal secretions from each of these patients yielded two or more of the above organisms on at least two different days. Prior to this outbreak, one to three patients on this unit were colonized each month. While attempting to identify the source of these organisms, we were surprised to learn that multiple-dose inhalers (MDIs), which are inserted into ventilator tubing to administer medications, were being used from patient to patient. Although it was departmental policy that these inhalers be cleaned with alcohol between patients, this was not always done. Culture of one of the six in-use MDIs grew A. anitratus and X. maltophilia with the same susceptibility patterns as the patient isolates. We decided to provide each patient with an inhaler and instructed hospital staff that these devices should not be shared. The colonization rate of nonfermenting gram-negative rods rapidly returned to the preoutbreak level. We do not know how widespread this practice of sharing MDIs is, but we want to make other hospital epidemiologists aware of our experience. REFERENCE