Burkholderia pseudomallei: another emerging pathogen in cystic fibrosis
- 1Adult Cystic Fibrosis Unit, The Prince Charles Hospital, Brisbane, Queensland, Australia
- 2Queensland Health Pathology Service, The Prince Charles Hospital, Brisbane, Queensland, Australia
- 3Public Health Microbiology, Queensland Health Scientific Services, Brisbane, Queensland, Australia
- 4Department of Infectious Diseases and Immunology, University of Sydney, New South Wales, Australia
- 5University of Queensland, Brisbane, Queensland, Australia
- Correspondence to:
Dr S C Bell
Department of Thoracic Medicine, The Prince Charles Hospital, Rode Road, Chermside 4032, Australia; scott_bellhealth.qld.gov.au
- Received 28 December 2002
- Accepted 17 August 2003
Abstract
Background:Burkholderia pseudomallei is an important cause of acute fulminant pneumonia and septicaemia in tropical regions of northern Australia and south east Asia. Subacute and chronic forms of the disease also occur. There have been three recent reports of adults with cystic fibrosis (CF) who presumably acquired B pseudomallei infection during extended vacations or residence in either Thailand or northern Australia.
Methods: The clinical course, molecular characteristics, serology and response to treatment are described in four adult CF patients infected with B pseudomallei. Polymerase chain reaction (PCR) based methods were used to confirm B pseudomallei and exclude B cepacia complex. Genotyping was performed using randomly amplified polymorphic DNA (RAPD) PCR and pulsed field gel electrophoresis (PFGE).
Results: Four patients are described with a mean duration of infection of 32 months. All but one patient lived in tropical Queensland. Two patients (with the longest duration of infection) deteriorated clinically and one subsequently died of respiratory failure. Both responded to intravenous treatment specifically targeting B pseudomallei. Another patient suffered two severe episodes of acute bronchopneumonia following acquisition of B pseudomallei. Eradication of the organism was not possible in any of the cases. PFGE of a sample isolate from each patient revealed the strains to be unique and RAPD analysis showed retention of the same strain within an individual over time.
Conclusions: These findings support a potential pathogenic role for B pseudomallei in CF lung disease, producing both chronic infection and possibly acute bronchopneumonia. Identical isolates are retained over time and are unique, consistent with likely environmental acquisition and not person to person spread. B pseudomallei is emerging as a significant pathogen for patients with CF residing and holidaying in the tropics.
