Distal Airways Bacterial Colonization and Inflammatory Pattern in Children With Chronic Lung Diseases

Background Children with chronic lung diseases are vulnerable to develop bacterial colonization of their distal airways. The aim of this study was to assess role of flexible bronchoscopy to determine distal airway microbial colonization and inflammation in children with chronic lung diseases compared with conventional methods. Methods Bronchoalveolar lavage fluid (BALF), sputum, and blood samples were collected from 10 healthy and 30 children with chronic lung diseases. All samples were subjected to microbiologic assessment, cytology assessment, and biochemical assessment of Lactic dehydrogenase enzyme and alkaline phosphatase enzyme levels as indicators for inflammation. Results Distal airway bacterial colonization by potentially pathogenic microorganisms was detected in 73% of the children with chronic lung diseases. The most common organism was Staphylococcus aureus followed by Escherichia coli, Pseudomonas aeruginosa, and Citrobacter freundii. BALF analysis was superior to sputum (odds ratio=5.5; 95% confidence interval: 1.6-19.7, P=0.004) and blood samples (odds ratio=38.5; 95% confidence interval: 6.4-302, P=0.0001) analyses as they missed detection of many organisms. Antibiogram analysis revealed that most of Gram-negative organisms were highly sensitive to imipenem, tobramycin, ceftriaxone, Garamycin, and amikacin. Most of Gram-positive organisms were highly sensitive to vancomycin, Dalacin, and oxacillin. All patients visualized to have ongoing distal airways inflammation, even when not colonized, had higher levels of inflammatory markers and cellular loads in comparison to the controls. Conclusions BALF sampling is a safe, technically simple procedure in children and has a significant diagnostic value compared with sputum or blood markers for distal airways bacterial colonization and inflammation.