Distal airways bacterial colonization and inflammatory pattern in children with different chronic lung diseases: a bronchoscopic study

Children with chronic lung diseases are vulnerable to develop bacterial colonization of their distal airways. However, this diagnosis is based usually on nonspecific samples, such as gastric lavage or sputum cultures. The aim of this study was to assess applicability of fibro-optic bronchoscope technique to determine distal airway microbial colonization and inflammation in children with chronic lung diseases compared to conventional methods. Bronchoscopic bronchoalveolar lavage fluid [BALF], sputum and blood samples were collected from 10 healthy children and 30 patients with chronic lung diseases [with different diagnoses]. All samples were subjected to microbiological assessment [direct films, cultures, and antibiogram test], cytology assessment and biochemical assessment of Lactic dehydrogenase enzyme [LDH] and Alkaline phosphatase enzyme [ALP] levels as indicators for ongoing pulmonary damage. Distal airway bacterial colonization by potentially pathogenic microorganisms [PPMs] was defined in 73% of children with the most common organism Staphylococcus aureus followed by E. coli, Pseudomonas aeruginosa, and Citrobacter freundii. BALF analysis was superior to sputum [OR=5.5; 95%CI: 1.6-19.7, P=0.004] and blood samples [OR=38.5; 95%CI: 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 imepenem, tobramycin, ceftriaxone, garamycin, and amikin. Most of gram positive organisms were highly sensitive to vancomycin, dalacin and oxacillin. All patients [even if not colonized] visualized ongoing distal airways inflammation and had higher levels of inflammatory markers and cellular loads in comparison to healthy controls. BAL fluid sampling is a safe, technically simple procedure in children and has a significant diagnostic value compared to sputum or blood markers for distal airways bacterial colonization and inflammation