Biofilm formation on the Provox ActiValve: Composition and ingrowth analyzed by Illumina paired-end RNA sequencing, fluorescence in situ hybridization, and confocal laser scanning microscopy

Background. The most frequent cause of voice prosthesis failure is microbial biofilm formation on the silicone valve, leading to destruction of the material and transprosthetic leakage. The Provox ActiValve valve is made of fluoroplastic, which should be insusceptible to destruction. The purpose of this study was to determine if fluoroplastic is insusceptible to destruction by Candida species. Methods. Thirty-three dysfunctional Provox ActiValves (collected 2011-2013). Biofilm analysis was performed with Illumina paired-end sequencing (IPES), assessment of biofilm-material interaction with fluorescence in situ hybridization (FISH), and confocal laser scanning microscopy (CLSM). Results. IPES (n = 10) showed that Candida albicans and Candida tropicalis are dominant populations on fluoroplastic and silicone. Microbial diversity is significantly lower on fluoroplastic. Lactobacillus gasseri is the prevalent bacterial strain on most voice prostheses. FISH and CLSM (n = 23): in none of the cases was ingrowth of Candida species present in the fluoroplastic. Conclusion. Fluoroplastic material of Provox ActiValve seems insusceptible to destruction by Candida species, which could help improve durability of voice prostheses. (C) 2015 Wiley Periodicals, Inc