Microbiological profile of tracheostomy patients with amyotrophic lateral sclerosis: a monocentric observational study

<bold>Background:</bold> Amyotrophic lateral sclerosis (ALS) is characterized by upper and lower motor neuron dysfunction. Respiratory failure is a common event in the natural history of the disease, and, in the final stages of the disease, tracheostomy is an option patients choose. <bold>Aims:</bold> (i) to determine the most common microorganisms identified in tracheostomies; (ii) to investigate if the prior duration of non-invasive ventilation (NIV) or gastrostomy (PEG) or tracheostomy impacts tracheo microbiology. <bold>Methods:</bold> We retrospectively analysed endotracheal aspiration results from charts of ALS patients living with tracheostomy and followed at the NEMO centre between 1st January and 31st December 2023. <bold>Results:</bold> 19 ALS patients (median age at onset: 60.30 [45.46 – 69.24]; male/female ratio: 2.80; bulbar/spinal ratio: 0.46) with 14 different microorganisms colonising tracheostomy were identified. Pseudomonas was present in 12 patients (63%). The longer the time in tracheostomy, the greater the number of microorganisms detected (r=0.49; p=0.0338) while no correlation emerged between the number of microorganisms and duration of PEG and NIV. Finally, 2 of 19 patients (11%) developed respiratory infection due to Pseudomonas. Respiratory acute events were not related to tracheostomy duration (10.19 months [8.93 – 11.44] vs 9.64 months [4.68 – 27.93] in patients with and without acute events respectively). <bold>Conclusion:</bold> Pseudomonas is the most prevalent colonising microrganism in our cohort. Tracheostomy duration seems to impact tracheo microbiology in terms of number of microorganisms but not seem to facilitate acute respiratory events.