Background: Alcaligenes (Achromobacter) xylosoxidans occasionally cause infections, mainly in immunocompromised hosts.
Methods: Three cases of bacteremia due to A. xylosoxidans observed at the Fundación Jiménez Díaz between 1985-1994 were described. Moreover, 38 single cases of bacteremia due to A. xylosoxidans and 21 episodes associated with outbreak were reviewed by using computerized bibliography data base MEDLINE (1970-december 1994).
Results: From 41 patients with bacteremia (including our 3 cases) reviewed, 27 were immunosuppressed hosts (twenty had neoplasia disease). The most common clinical presentation was primary bacteremia (11 cases, 27%) and pneumonia (10, 24%), followed by catheter-associated bacteremia (8, 20%), meningitis (4), bacteremia from abdominal cavity (4), endocarditis (3) and pyelonephritis (1). The mortality rate was higher (39%), specially in patients whom were a intensive care unit acquisition (87%), and illness with endocarditis (100%). No patient with catheter-related bacteremia died. All of 21 outbreak episodes of bacteremia had a autolimited form and low mortality (4.8%).
Conclusion: A. xylosoxidans is a microorganism with demonstrated capacity of cause bacteremia, mainly in immunocompromised hosts, with high mortality rates. Sometimes, it causes outbreaks of bacteremia with low mortality.