Epidemiology and Clinical Course of Burkholderia cepacia Complex Infections, Particularly Those Caused by Different Burkholderia cenocepacia Strains, among Patients Attending an Italian Cystic Fibrosis Center

Abstract

In this study, the epidemiology of Burkholderia cepacia complex (Bcc) recovered from the sputum of 75 patients attending the Genoa Cystic Fibrosis (CF) Center at the Gaslini Children's Hospital (Genoa, Italy) was investigated, and the clinical course of the CF patients infected with the different species and genomovars of Bcc was evaluated. All isolates were analyzed for genomovar status by recA gene polymorphism and subsequently random amplified polymorphic DNA fingerprinting. Burkholderia cenocepacia is the predominant species recovered from the CF patients infected with Bcc at the Genoa CF Center. Of the other eight species comprising the Bcc, only a few isolates belonging to B. cepacia genomovar I, Burkholderia stabilis, and Burkholderia pyrrocinia were found. Of the four recA lineages of B. cenocepacia, most patients were infected by epidemic strains belonging to lineages IIIA and IIID, whereas only a few patients harbored IIIB strains. Patient-to-patient spread of Bcc among CF patients was mostly associated with B. cenocepacia, in particular with strains belonging to recA lineages IIIA and IIID. The mortality of CF patients infected with Bcc at the Genoa CF Center was significantly higher than mortality among CF patients not infected with Bcc. All of the deaths were associated with the presence of B. cenocepacia, except the case of a patient infected with B. cepacia genomovar I. Within B. cenocepacia, infection with epidemic strains belonging to lineages IIIA and IIID was associated with higher rates of mortality than was infection with lineage IIIB strains. No significant differences in lung function, body weight, and mortality rate were observed between patients infected with epidemic strains belonging to either B. cenocepacia IIIA or B. cenocepacia IIID.

Use of Lung Transplantation Survival Models to Refine Patient Selection in Cystic Fibrosis

“…Although collection of additional genomovar information is desirable, we are uncertain if it will be helpful. New information suggests that infections even by a single genomovar of B. cepacia may have greatly differing severity depending on the patient or geographic region (27).…”

Transmission of Burkholderia cepacia Complex: Evidence for New Epidemic Clones Infecting Cystic Fibrosis Patients in Italy

“…Of 225 isolates, 208 isolates were confirmed as B. cepacia complex bacteria, representing 73.5% of Italian CF patients colonized by B. cepacia complex (22,44). In 2002, the Italian Register of Cystic Fibrosis reported 3,791 living patients (52a); therefore, the overall prevalence of B. cepacia complex is 7.5%.…”

Revised Approach for Identification of Isolates within the Burkholderia cepacia Complex and Description of Clinical Isolates Not Assigned to Any of the Known Genomovars

“…Reliable identification is important, since some genomovars, particularly the ET12 lineage of genomovar IIIA (15), are associated with high transmissibility between patients and a poor prognosis (7). B. multivorans and B. cenocepacia account for the majority of isolates from CF patients, with patient-to-patient spread mainly being associated with genomovars IIIA (8,12) and IIIB (3,6), although reports also describe epidemic spread of lineages of genomovar IIID (13) and B. dolosa (1,2). The highest mortality rate has been associated with genomovar IIIA, but reports have now appeared that suggest that genomovar IIID and B. dolosa are similarly virulent (2,9,13).…”