Pseudomonas aeruginosa colonisation in patients without bronchiectasis

Introduction In non Cystic Fibrosis bronchiectasis, Pseudomonas colonisation is a marker of severity. In patients with COPD, colonisation with Haemophilus Influenza and Streptococcus Pneumoniae causes an increased exacerbation rate. Pseudomonas colonisation has been reported to be 20% in these patients but the significance of this is yet to be determined. Method We opportunistically reviewed cases of patients colonised with Pseudomonas from April 2012 to April 2013 at Worcestershire Acute Hospitals NHS Trust retrospectively. The reviewed cases were 28% of all patients with positive sputum growth of Pseudomonas. Results 76 cases were reviewed; 43(57%) female and 33(43%) male. The mean age was 70 years. 57(75%) had radiological evidence of bronchiectasis and 15 (20%) did not (no imaging in 4 (5%)). Lung function was performed in 61 (80%) of patients with the following results: Very severe obstruction: 10 (16%); Severe obstruction: 20 (33%); Moderate obstruction: 21 (34%); Mild obstruction: 3 (5%); Other 4 (7%). In those with bronchiectasis, 45 (79%) had obstructive lung function tests, 55 (96%) were on high dose inhaled steroids. Of the 15 patients without bronchiectasis, 9 (60%) had airway obstruction and all were on high dose inhaled corticosteroids. Charactertistics of patients colonised with Pseudomonas Bronchiectasis No Bronchiectasis Obstructive Lung Function (n(%)) 45 (79) 9 (60) On High Dose Inhaled Cortocosteroids (n(%)) 55 (96) 9 (60) Conclusion 20% of patients colonised with Pseudomonas had no radiological evidence of bronchiectasis. 60% of these patients were on high dose inhaled corticosteroids. The clinical relevance is not clear but this small study demonstrates the need for further investigation.