WS01.06 Inducing sputum in the adult cystic fibrosis post-modulator era

Objectives: CFTR modulators have dramatically changed the landscape of CF, leading to reduced frequency of available sputum sampling for pathogen surveillance. Induced sputum (IS) samples via a variety of physiotherapy methods present an alternative to cough swabs to monitor microbial growth. The aim was to evaluate the efficacy of an IS service at the All Wales Adult CF Centre (AWACFC) for microbial surveillance. Methods: Patients underwent an IS if they were unable to provide a sputum sample within the previous 12 months. Each session took approximately 60 minutes of physiotherapy time. Methods were chosen by the patient and included exercise, Metaneb®, oscillatory PEP and manual techniques. Retrospective data was collected from 15 months of IS sessions and cough swabs in Cardiff including method used, samples produced and microbial yield. Results: A total of 45 IS were completed. Success rate for the patient producing at least 1 sample was 87%. Exercise combined with hypertonic saline was the most common method used (N = 30). Exercise had the biggest success rate versus other IS methods combined (80% vs 71%). 74% of IS samples isolated at least 1 specific microbe compared to 16% of cough swabs from the same cohort. Isolates grown included Mycobacterium chelonae, Pseudomonas aeruginosa, Haemophilus influenzae, Staphylococcus aureus and Stenotrophomonas maltophilia. 1 patient reported vomiting post IS, but otherwise all other sputum inductions were tolerated well with no other reported adverse events. Conclusion: IS resulted in increased microbial surveillance in the absence of spontaneously produced sputum. IS was well tolerated with a high success rate. Exercise was the most common method used and had a higher success rate. Sputum induction sessions also presented an opportunity for the physiotherapy team to evaluate airways clearance techniques.