Achromobacter xylosoxidans respiratory tract infections in cystic fibrosis patients

Abstract

Achromobacter xylosoxidans is a ubiquitous Gram‐negative non‐fermenting rod, recently characterized as an emerging pathogen in cystic fibrosis (CF) patients. Its pathogenic potential and prevalent transmission routes are still unclear. This study investigated the PFGE genetic pattern and antimicrobial resistance profile of 42 A. xylosoxidans isolates obtained over 4 years from the respiratory tract of 22 CF patients. By genotypic analysis, 31 isolates were attributed to 8 distinct PFGE patterns (A–H), whereas 11 isolates were not typable because their DNA was not restricted by XbaI and DraI restriction enzymes. The majority of the isolates showed multidrug resistance; imipenem and piperacillin were the most active drugs. During the course of A. xylosoxidans chronic infection forced expiratory volume and body mass index values were not significantly lowered. The demonstration of widespread antibiotic resistance underscores the importance of antibiogram‐directed therapy. Our data suggest that in some cases the infection may have been acquired from other patients or from a common contaminated source. Further epidemiological studies may be important for the design and implementation of prophylactic measures in CF centers.

Prevalence and Outcomes of Achromobacter Species Infections in Adults with Cystic Fibrosis: a North American Cohort Study

“…An increased need for antimicrobials (11) and hospitalization (26) have also been reported. We found no evidence of clinical decline (lung function loss or risk of PEx) following infection, nor was there a significant change in nutritional status (BMI) over the course of follow-up, similar to the results of a previous study (12). It may be valuable to follow-up with patients for a longer duration to see if such correlations become evident.…”

“…The cumulative prevalence of Achromobacter isolation of 11% in our center is comparable to those previously reported for small centers, which ranged from 5 to 29% (11,12), although this spans 3 decades, making the incidence of infection very low. While others have reported that older patients and patients with greater lung disease burden appear to be predisposed to infection with Achromobacter species (11, 18), we did not observe any correlation between age, nutritional status, CF comorbidities, baseline lung status, or home oxygen use and incident infection.…”

“…Despite the increasingly frequent isolation of Achromobacter from CF patients, its pathogenicity is unclear (11,12,26), though the growing body of evidence seems to support the significance of its isolation (17,37,38). Although PEx in CF patients are common, we hypothesized a discernible clinical impact with subsequent lung function decline after Achromobacter detection.…”

“…Studies have attributed persistent Achromobacter infections predominantly to A. xylosoxidans (2,11,12,18), with a few exceptions, including A. insuavis and A. dolens (5,6). We now know that this may represent a broader species distribution.…”

Multilocus Sequence Analysis of Isolates of Achromobacter from Patients with Cystic Fibrosis Reveals Infecting Species Other than Achromobacter xylosoxidans

“…It is well known that A. xylosoxidans can cross-infect patients (15,19,21,22,25,27,36). In several cases we found strains of Achromobacter with identical sequences at all five MLSA loci.…”