Asthma in primary ciliary dyskinesia: A local airway response rather than a feature of systemic allergic response.

<bold>Rationale:</bold> Antigen stasis on the airway epithelial surface of patients with primary ciliary dyskinesia (PCD) leads to inflammation and oxidative stress (PMID: 38318660). Further, we and others have shown that PCD patients commonly have bronchial hyper-reactivity (BHR). Here, we asked whether this asthma diathesis in PCD is associated with a generalized atopic march- perhaps initiated by chronic antigen stasis in the nose and lungs – or whether it is more associated with a local, non-T2 reaction in the airways. <bold>Methods:</bold> We began by validating previous work in two large, electronic health record based databases (INPCR and IBM Explorys) by confirming that patients with ICD10 codes for both bronchiectasis and situs inversus totalis (as a surrogate for PCD, as there is no formal ICD10 for PCD) have an increase in the odds of having an asthma ICD10, when compared to age and sex matched controls at a ratio of 1:3. We then queried the INPCR database in the same way, but asking whether the PCD population were also more likely to have eczema. <bold>Results:</bold> 142 PCD and 426 control subjects were evaluated. We found that PCD was associated with a 9-fold increase in the odds for having asthma (OR: 9.65; 95%CI: 5.20 – 17.90, p< 001), but only a 7 -fold increase in the odds for having eczema (lower than the odds of having asthma, OR: 7.71; 95%CI: 1.59, 37.43, p=0.011). <bold>Conclusions:</bold> These data suggest that antigen stasis in the PCD airway commonly leads to asthma in a manner that may be only partly dependent on the classic atopic march. This observation is important for the management of PCD patients and may inform future studies of the pathogenesis of ciliopathy -related asthma.