C61-05 Airway Microbiologic Profile in Primary Ciliary Dyskinesia: A Single-center Study

Abstract Rationale Understanding of airway microbiota is integral to prescribing clinical treatment regimens and for the prognosis of individual patients. It is currently unclear how microbiota may change over the course of time for an individual with primary ciliary dyskinesia (PCD). Methods Chart review of patients in PCD Center at WashU Medicine/Saint Louis Children’s Hospital (SLCH); a large PCD center with wide referral base. Results Fifty-three (53) patients diagnosed with PCD had culture results reviewed in the electronic medical record from 2017 − 2025. Five hundred fifty-one (551) airway cultures were collected in clinic as part of routine screening. Two hundred seventy-two (272) cultures grew a single organism, sixty-nine (69) grew two, and ten (10) grew three, for a total of three hundred fifty-one (351) positive cultures. Sixty-three percent (63.7%) of patients had a positive culture for any organism. The most common organisms identified were methicillin-susceptible Staphylococcus aureus (71.6%), Pseudomonas aeruginosa (33.9%), Streptococcus pneumoniae (30.1%), Stenotrophomonas maltophilia (16.9%), Haemophilus influenzae (11.3%), Acinetobacter (11.3%), and Moraxella catarrhalis (9.4%). Forty percent (40%) of patients grew Pseudomonas aeruginosa at least once, with age at acquisition ranging from 1-21 years. Acquisition was highly correlated within sibling groups, with 50-100% of siblings having positive cultures after the index case tested positive. Twenty out of the fifty-three patients (37.7%) had PCD-related bronchiectasis with 11 of them (55%) grew Pseudomonas aeruginosa at least once. Eradication attempts at Pseudomonas were largely successful, with 62.5% of patients received antibiotics for eradication showed no subsequent growth of Pseudomonas on repeated cultures. Microbial diversity could be wide within an individual patient, with up to six different organisms identified over the course of some patients’ culture results. With the noted exception of sibling groups, there was no clear pattern of microorganism acquisition over time within or between patients in our center. Conclusions Microbial diversity within patients at a large PCD center did not show any significant patterns of shift toward or away from certain organisms over time. The most identified organism was Staphylococcus aureus with Pseudomonas aeruginosa also noted at a significant rate. Within sibling groups, the acquisition of Pseudomonas aeruginosa was very high after the index sibling had tested positive. Eradication of Pseudomonas aeruginosa had a good chance of success, even within the sibling groups, and should strongly be considered as part of a treatment plan. This abstract is funded by: None