Investigation of an outbreak of wound infections due to Alcaligenes xylosoxidans transmitted by chlorhexidine in a burns unit

Alcaligenes xylosoxidans, an environmental gram-negative bacillus, was isol ated within a 1-month period from six patients in a pediatric burns unit. T welve isolates were studied, one from each of the six patients (five from w ound cultures and one from a blood culture) and one from each of six contam inated atomizers containing chlorhexidine diluted to 600 mg/l. The biochemi cal and susceptibility patterns of all the isolates were similar, and their DNA enzyme restriction patterns were identical. The epidemic strain of Alc aligenes xylosoxidans was probably introduced into the atomizers during han dling of the diluted solution, which failed to eliminate it.