Besides Pseudomonas aeruginosa, which organism is an important cause of lower respiratory tract infections in patients with cystic fibrosis?

• A. Actinobacillus actinomycetemcomitans
• B. Burkholderia cepacia
• C. Chiyseobacterium meningosepticum
• D. Serratia marcescens

Answer: (B)

Burkholderia cepacia complex stands out as a major CF pathogen after Pseudomonas because it commonly colonizes the CF airway, can cause rapid clinical deterioration known as cepacia syndrome, and is notoriously hard to treat due to intrinsic antibiotic resistance. It also spreads readily between patients, so infection control and careful cohorting in CF clinics become crucial. Once established, eradication is difficult and colonization can influence transplant eligibility in some centers. While other bacteria can be found in CF lungs, none carry the same combination of aggressive disease potential, treatment challenges, and transmission risk as Burkholderia cepacia complex.