Biofilm in voice prosthesis: A prospective cohort study and laboratory tests using sonication and SEM analysis

Concordance in bacterial colonization profiles between voice prostheses and oral microbiota post-laryngectomy: An experimental study

OBJECTIVE

Knowledge about voice prosthesis microbial colonization is vital in laryngectomized patients' quality of life (QoL). Herein, we aimed to explore the relationship between oral microbial patterns, demographic variables and voice prosthesis performance.

METHODS

Thirty laryngectomy patients were assessed for microbial colonization in their voice prostheses and oral cavities. Factors like age, proton pump inhibitor (PPI) usage, and alcohol consumption were considered.

RESULTS

Participants' average age was 74.20 ± 7.31 years, with a majority on PPIs. Staphylococcus aureus was the most common bacterium in prostheses (53 %), followed by Pseudomonas aeruginosa (27 %). Candida albicans was the primary fungal colonizer (67 %). A statistically significant moderate correlation was found between fungal species before and after oral rinsing (p = 0.035, Phi=0.588, Cramer's V = 0.416). Voice prosthesis and oral cavity microbiota profiles showed significant concordance (kappa=0.315, p < 0.004). Among subgroup analyses, bacterial patterns of colonization did not significantly influence VHI (p = 0.9555), VrQoL (p = 0.6610), or SF-36 (p = 0.509) scores. Conversely, fungal patterns of VP colonization significantly impacted subjective voice scores, with Candida krusei demonstrating better VHI (35.25 ± 3.63 vs. 44.54 ± 6.33; p = 0.008), VrQoL (7.13 ± 1.69 vs. 10.73 ± 2.00; p = 0.001), and SF-36 (69.36 ± 7.09 vs. 76.50 ± 7.73; p = 0.051) scores compared to C. albicans.

CONCLUSIONS

There was a significant correlation between the oral microbiota and voice prosthesis colonization. These insights can inform improved care strategies for voice prostheses, enhancing patient outcomes.

Is Oral Microflora Related to Development of Malfunction in Patients Using Voice Prosthesis?

Background: this prospective study investigated the correlation between the oral bacterial microflora and the microflora found in voice prostheses (VPs) among 20 patients who had undergone laryngectomy. The aim was to explore the associations between the microflora's presence and the malfunction of VPs, along with the association between the predominant microorganism and the longevity of VPs. Methods: the research process included gathering medical histories, conducting ENT examinations, replacing VPs, and performing check-ups every four months for a period of 15.5 months. Additionally, microbiological examinations, blood tests, and voice change surveys were conducted. Results: a correlation between the microflora isolated from VPs and that from oral rinses was demonstrated in a large percentage of patients who experienced a loss of prosthetic functional efficiency. The correlation analysis between the type of microorganism and the lifespan of VPs showed a non-significant Pearson correlation coefficient (r = 0.043, p = 0.678). Conclusions: there is no significant linear correlation between the predominant microorganism and the average lifespan of VPs.

Antibiofilm Strategies in Neonatal and Pediatric Infections

Biofilm-related infections pose significant challenges in neonatal and pediatric care, contributing to increased morbidity and mortality rates. These complex microbial communities, comprising bacteria and fungi, exhibit resilience against antibiotics and host immune responses. Bacterial species such as Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis commonly form biofilms on medical devices, exacerbating infection risks. Neonates and children, particularly those in intensive care units, are highly susceptible to biofilm-associated infections due to the prolonged use of invasive devices, such as central lines and endotracheal tubes. Enteral feeding tubes, crucial for neonatal nutritional support, also serve as potential sites for biofilm formation, contributing to recurrent microbial contamination. Moreover, Candida species, including Candida pelliculosa, present emerging challenges in neonatal care, with multi-drug resistant strains posing treatment complexities. Current antimicrobial therapies, while important in managing infections, often fall short in eradicating biofilms, necessitating alternative strategies. The aim of this review is to summarize current knowledge regarding antibiofilm strategies in neonates and in children. Novel approaches focusing on biofilm inhibition and dispersal show promise, including surface modifications, matrix-degrading enzymes, and quorum-sensing inhibitors. Prudent use of medical devices and exploration of innovative antibiofilm therapies are imperative in mitigating neonatal and pediatric biofilm infections.

Strategies for Inhibition of Biofilm Formation on Silicone Rubber Voice Prostheses: A Systematic Review

BACKGROUND

Lifetime elongation of the silicone voice rubber prostheses by inhibition of biofilm formation is a primary objective in voice restoration of laryngectomized patients. This systematic review sought to explore the existing strategies in this direction.

MATERIALS

We conducted a systematic search of both in vitro and in vivo literature published in PubMed, Scopus, and Cochrane Central Register of Controlled Trials, until December 31, 2022, for published and unpublished trials assessing the strategies for inhibiting biofilm formation on silicone rubber voice prostheses, and appraised quality assessment with the modified Consolidated Standards of Reporting Trials tool. We analyzed the infection prevention capacity of the included antibacterial and antifungal agents.

RESULTS

The qualitative synthesis showed that both surface modification methods and prophylactic treatment of silicone rubber voice prostheses present adequate antibiofilm activity. Of note, the majority of the suggested prosthetic surfaces were not chronically exposed to both human fluids and biofilm-forming microorganisms.

CONCLUSION

Various experimental methods provide promising antibiofilm activity and, thus, possible lifespan elongation of silicone rubber voice prostheses.

Does Prophylactic Replacement of Voice Prosthesis Make Sense? A Study to Predict Prosthesis Lifetime

OBJECTIVE

Voice prosthesis leakage significantly affects the quality of life of patients undergoing laryngectomy, causing insecurity and frequent unplanned hospital visits and costs. In this study, the concept of prophylactic voice prosthesis replacement was explored to prevent leakages.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary hospital.

METHODS

This study included all patients who underwent laryngectomy between 2000 and 2012 in the Netherlands Cancer Institute. Device lifetimes and voice prosthesis replacements of a retrospective cohort were used to calculate the number of needed voice prostheses per patient per year to prevent 70% of the leakages by prophylactic replacement. Various strategies for the timing of prophylactic replacement were considered: adaptive strategies based on the individual patient's history of replacement and fixed strategies based on the results of patients with similar voice prosthesis or treatment characteristics.

RESULTS

Patients used a median 3.4 voice prostheses per year (range, 0.1-48.1). We found high inter- and intrapatient variability in device lifetime. When prophylactic replacement is applied, this would become a median 9.4 voice prostheses per year, which means replacement every 38 days, implying >6 additional voice prostheses per patient per year. The individual adaptive model showed that preventing 70% of the leakages was impossible for most patients and only a median 25% can be prevented. Monte-Carlo simulations showed that prophylactic replacement is not feasible due to the high coefficient of variation (SD/mean) in device lifetime.

CONCLUSION

Based on our simulations, prophylactic replacement of voice prostheses is not feasible due to high inter- and intrapatient variation in device lifetime.

Biocompatible Materials in Otorhinolaryngology and Their Antibacterial Properties

For decades, biomaterials have been commonly used in medicine for the replacement of human body tissue, precise drug-delivery systems, or as parts of medical devices that are essential for some treatment methods. Due to rapid progress in the field of new materials, updates on the state of knowledge about biomaterials are frequently needed. This article describes the clinical application of different types of biomaterials in the field of otorhinolaryngology, i.e., head and neck surgery, focusing on their antimicrobial properties. The variety of their applications includes cochlear implants, middle ear prostheses, voice prostheses, materials for osteosynthesis, and nasal packing after nasal/paranasal sinuses surgery. Ceramics, such as as hydroxyapatite, zirconia, or metals and metal alloys, still have applications in the head and neck region. Tissue engineering scaffolds and drug-eluting materials, such as polymers and polymer-based composites, are becoming more common. The restoration of life tissue and the ability to prevent microbial colonization should be taken into consideration when designing the materials to be used for implant production. The authors of this paper have reviewed publications available in PubMed from the last five years about the recent progress in this topic but also establish the state of knowledge of the most common application of biomaterials over the last few decades.

Plant-derived nanotherapeutic systems to counter the overgrowing threat of resistant microbes and biofilms

Since antiquity, the survival of human civilization has always been threatened by the microbial infections. An alarming surge in the resistant microbial strains against the conventional drugs is quite evident in the preceding years. Furthermore, failure of currently available regimens of antibiotics has been highlighted by the emerging threat of biofilms in the community and hospital settings. Biofilms are complex dynamic composites rich in extracellular polysaccharides and DNA, supporting plethora of symbiotic microbial life forms, that can grow on both living and non-living surfaces. These enforced structures are impervious to the drugs and lead to spread of recurrent and non-treatable infections. There is a strong realization among the scientists and healthcare providers to work out alternative strategies to combat the issue of drug resistance and biofilms. Plants are a traditional but rich source of effective antimicrobials with wider spectrum due to presence of multiple constituents in perfect synergy. Other than the biocompatibility and the safety profile, these phytochemicals have been repeatedly proven to overcome the non-responsiveness of resistant microbes and films via multiple pathways such as blocking the efflux pumps, better penetration across the cell membranes or biofilms, and anti-adhesive properties. However, the unfavorable physicochemical attributes and stability issues of these phytochemicals have hampered their commercialization. These issues of the phytochemicals can be solved by designing suitably constructed nanoscaled structures. Nanosized systems can not only improve the physicochemical features of the encapsulated payloads but can also enhance their pharmacokinetic and therapeutic profile. This review encompasses why and how various types of phytochemicals and their nanosized preparations counter the microbial resistance and the biofouling. We believe that phytochemical in tandem with nanotechnological innovations can be employed to defeat the microbial resistance and biofilms. This review will help in better understanding of the challenges associated with developing such platforms and their future prospects.

Assessment of Ceragenins in Prevention of Damage to Voice Prostheses Caused by Candida Biofilm Formation

This study aimed to investigate the potential application of ceragenins (CSAs) as new candidacidal agents to prevent biofilm formation on voice prostheses (VPs). The deterioration of the silicone material of VPs is caused by biofilm growth on the device which leads to frequent replacement procedures and sometimes serious complications. A significant proportion of these failures is caused by Candida species. We found that CSAs have significant candidacidal activities in vitro (MIC; MFC; MBIC), and they effectively eradicate species of yeast responsible for VP failure. Additionally, in our in vitro experimental setting, when different Candida species were subjected to CSA-13 and CSA-131 during 25 passages, no tested Candida strain showed the significant development of resistance. Using liquid chromatography–mass spectrometry (LC-MS), we found that VP immersion in an ethanol solution containing CSA-131 results in silicon impregnation with CSA-131 molecules, and in vitro testing revealed that fungal biofilm formation on such VP surfaces was inhibited by embedded ceragenins. Future in vivo studies will validate the use of ceragenin-coated VP for improvement in the life quality and safety of patients after a total laryngectomy.

A one-year time frame for voice prosthesis management. What should the physician expect? Is it an overrated job?

Management of late complications represents the main reason for reluctance in using voice prosthesis rehabilitation. The aim of this paper is to report our experience by describing the one-year management of a large cohort of patients in order to clarify how demanding management is in terms of burden on clinicians. Between June 2017 and June 2018, each access made at the Otolaryngology Clinic of our Institute for issues related to prosthesis by 70 laryngectomised patients rehabilitated by voice prosthesis was registered in a specific database. A review of the data provided information on the incidence, management and outcomes of adverse events encountered during the selected time frame. In addition, a T test was used to evaluate the differences between irradiated and non-irradiated patients and between primary and secondary tracheo-oesophageal-puncture. Leakage through the prosthesis was the most common cause for access (51.86%). The median number of accesses per patient per year was 3.47. The speech therapist autonomously managed 18.1% of accesses. The median number of accesses per patient per year needing a physician was 2.84. The median lifetime of the prosthesis was 4.85 months. Radiotherapy or modality (primary or secondary) of the puncture did not influence the number of accesses per year or the prosthesis lifetime. This retrospective analysis of results highlighted the most frequent issues and the most effective measures to deal with them, which allowed us to define a systematic algorithm to standardise and ease long-term outpatient management.

Preventing Biofilm Formation and Development on Ear, Nose and Throat Medical Devices

Otorhinolaryngology is a vast domain that requires the aid of many resources for optimal performance. The medical devices utilized in this branch share common problems, such as the formation of biofilms. These structured communities of microbes encased in a 3D matrix can develop antimicrobial resistance (AMR), thus making it a problem with challenging solutions. Therefore, it is of concern the introduction in the medical practice involving biomaterials for ear, nose and throat (ENT) devices, such as implants for the trachea (stents), ear (cochlear implants), and voice recovery (voice prosthetics). The surface of these materials must be biocompatible and limit the development of biofilm while still promoting regeneration. In this respect, several surface modification techniques and functionalization procedures can be utilized to facilitate the success of the implants and ensure a long time of use. On this note, this review provides information on the intricate underlying mechanisms of biofilm formation, the large specter of implants and prosthetics that are susceptible to microbial colonization and subsequently related infections. Specifically, the discussion is particularized on biofilm development on ENT devices, ways to reduce it, and recent approaches that have emerged in this field.

Diagnosis of biofilm infections: current methods used, challenges and perspectives for the future

The diagnosis of biofilms continues to be a challenge, and there is no standardized protocol for such a diagnosis in clinical practice. In addition, some proposed methodologies are expensive to require significant amounts of time and a high number of trained staff, making them impracticable for clinical practice. In recent years, mass spectrophotometry/matrix-assisted laser desorption ionization time of flight (MALDI-TOF) has been applied it in biofilm studies. However, due to several problems and limitations of the technique, MALDI-TOF is far from being the gold standard for identifying biofilm formation. The omics analysis may prove to be a promising strategy for the diagnosis of biofilms in clinical laboratories since it allows the identification of pathogens in less time than needed for conventional techniques and in a more specific manner. However, omic tools are expensive and require qualified technical expertise, and an analysis of the data obtained needs to be careful not to neglect subpopulations in the biofilm. More studies must therefore be developed for creating a protocol that guarantees rapid biofilm identification, ensuring greater chances of success in infection control. This review discusses the current methods of microbial biofilm detection and future perspectives for its diagnosis in clinical practice.

Periprosthetic Leakage in Tracheoesophageal Prosthesis: Proposal of a Standardized Therapeutic Algorithm

OBJECTIVE

Periprosthetic leakage represents the most demanding long-term complication in the voice prosthesis rehabilitation. The aim of this article is to discuss the various causes of periprosthetic leakage and to propose a systematic management algorithm.

STUDY DESIGN

Retrospective cohort study.

SETTING

Otolaryngology clinic of the University Polyclinic A. Gemelli-IRCCS Foundation.

METHODS

The study included 115 patients with voice prosthesis who were treated from December 2014 to December 2019. All patients who experienced periprosthetic leakage were treated with the same step-by-step therapeutic approach until it was successful. Incidence, management, and success rate of every attempt are analyzed and discussed.

RESULTS

Periprosthetic leakage was reported 330 times by 82 patients in 1374 clinic accesses. Radiotherapy, timing of tracheoesophageal puncture, and type of total laryngectomy (primary or salvage) did not influence the incidence of periprosthetic leakage. Salvage total laryngectomy increases the risk of more clinically relevant leakages.

CONCLUSION

By using a systematic algorithm with a step-by-step standardized approach, periprosthetic leakage management could become a less treacherous issue.

Complications associated with tracheoesophageal voice prostheses from 2010 to 2020: A MAUDE study

PURPOSE

Tracheoesophageal puncture with voice prosthesis placement remains the gold standard for voice restoration following total laryngectomy, but may cause various complications. This study aims to summarize patient-related and device-related adverse events associated with tracheoesophageal puncture and voice prosthesis placement.

MATERIALS AND METHODS

The U.S. Food and Drug Administration's Manufacturer and User Facility Device Experience database was queried for reports of adverse events related to tracheoesophageal puncture with voice prosthesis placement from January 1, 2010, to April 30, 2020. Data were extracted from reports pertaining to tracheoesophageal prostheses.

RESULTS

Seventy-seven reports involving tracheoesophageal voice prostheses were identified, from which 111 adverse events were extracted. Of these, 58 (52.3%) were patient-related, while 53 (47.7%) were device-related. The most frequently reported patient-related adverse events were aspirated prosthesis (24 [41.4%]), foreign body during placement (11 [19.0%]), aspiration pneumonia (9 [15.5%]), and aspirated brush tip (8 [13.8%]). The most common device-related adverse events were detached brush tip (15 [28.3%]), leak (14 [26.4%]), and torn esophageal flange (11 [20.8%]).

CONCLUSIONS

While tracheoesophageal puncture with voice prosthesis placement has revolutionized voice rehabilitation following total laryngectomy, the procedure may be associated with adverse events both at the time of placement and later. Interventions aimed at improving both physician and patient education may help reduce adverse events attributed to improper use. Further research is needed to clarify optimal approaches to education.

Biofilm Growth Causes Damage to Silicone Voice Prostheses in Patients after Surgical Treatment of Locally Advanced Laryngeal Cancer

Voice prosthesis implantation with the creation of a tracheoesophageal fistula is the gold standard procedure for voice rehabilitation in patients after a total laryngectomy. All patients implanted with a voice prosthesis (VP) have biofilms of fungi and bacteria grow on their surface. Biofilm colonization is one of the main reasons for VP degradation that can lead to VP dysfunction, which increases the high risk of pneumonia. In a 20-month evaluation period, 129 cases of prostheses after replacement procedures were investigated. Microbiological examination of the biofilms revealed that there were four of the most common fungi species (Candida spp.) and a large variety of bacterial species present. We studied the relationship between the time of proper function of Provox VP, the microorganism composition of the biofilm present on it, and the degradation level of the silicone material. Evaluation of the surface of the removed VP using an atomic force microscope (AFM) has demonstrated that biofilm growth might drastically change the silicone's mechanical properties. Changes in silicone stiffness and thermal properties might contribute to the failure of VP function. Our data can serve in future studies for the development of methods to prevent or inhibit biofilm formation on the VP surface that would translate to an increase in their durability and safety.