Objective To study the frequency of microbial colonisation and development of resistance in common antibiotics in bronchoalveolar lavage (BAL) specimens obtained from paediatric intensive care unit (PICU) patients and correlate with clinical indices.

Material/Methods Retrospective study (2006–7). Ninety-two BAL cultures of intubated or patients with tracheostoma were evaluated and correlated with length of PICU stay (LOS), severity of disease, duration of mechanical ventilation and development of ventilatory acquired pneumonia (VAP) or sepsis.

Results Twelve patients (21.4%) with pre-existing chronic disease (PCD) had multiple PICU admissions (2–8) (home 42%, other district hospitals 17% vs 0% and 59% in children with one PICU admission, p<0.001). Thirteen BAL cultures (14.1%) grew Gram(+) bacteria, with Staphylococcus aureus being the commonest with 25% resistant strains (MRSA). Gram(−) bacteria were grown in 47 BAL cultures with a prevalence of Pseudomonas aeruginosa (70.2%), which was characterised by “specific impermeability” in imipeneme (45.4%). Four (4.3%) developed Candida albicans. The development of resistant strains was not correlated with mortality (7.1% vs 7.8%), severity of disease scores, LOS or mechanical ventilation as well as with sepsis (3.6% vs 7.8%) or VAP (10.7% vs 14.1%). It differed significantly, however, between groups with or without multiple PICU admissions (p<0.0001), PCD (p<0.01) and tracheostoma (p<0.0001). Only the presence of tracheostoma and positive initial BAL were independently correlated with the development of resistant strains.

Conclusions Although restricted antibiotic policy in PICU ensured low resistance rates, isolation of resistant P aeruginosa and MRSA strains in BAL, especially among patients with chronic disease, highlights the necessity for intense antibiotic surveillance.