SP7 and congenital bilateral aplasia of vas deferens from CFTR mutation: Valve interstitial cells from CAVD exhibited spontaneous in vitro calcification, unlike controls.<h4>Conclusion</h4>The early osteogenic marker osterix was found to be upregulated in patients whose valves tested positive for microbial DNA, suggesting a potential role for bacteria in driving cellular differentiation towards an osteoblastic phenotype in CAVD.