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Frontiers in Cellular and Infection... 2021Osseointegration is a well-established concept used in applications including the percutaneous Bone-Anchored Hearing System (BAHS) and auricular rehabilitation. To date,...
Multimodal Analysis of the Tissue Response to a Bone-Anchored Hearing Implant: Presentation of a Two-Year Case Report of a Patient With Recurrent Pain, Inflammation, and Infection, Including a Systematic Literature Review.
Osseointegration is a well-established concept used in applications including the percutaneous Bone-Anchored Hearing System (BAHS) and auricular rehabilitation. To date, few retrieved implants have been described. A systematic review including cases where percutaneous bone-anchored implants inserted in the temporal bone were retrieved and analyzed was performed. We also present the case of a patient who received a BAHS for mixed hearing loss. After the initial surgery, several episodes of soft tissue inflammation accompanied by pain were observed, leading to elective abutment removal 14 months post-surgery. Two years post-implantation, the implant was removed due to pain and subjected to a multiscale and multimodal analysis: microbial DNA using molecular fingerprinting, gene expression using quantitative real-time polymerase chain reaction (qPCR), X-ray microcomputed tomography (micro-CT), histology, histomorphometry, backscattered scanning electron microscopy (BSE-SEM), Raman spectroscopy, and fluorescence hybridization (FISH). Evidence of osseointegration was provided micro-CT, histology, BSE-SEM, and Raman spectroscopy. Polymicrobial colonization in the periabutment area and on the implant, including that with and , was determined using a molecular analysis a 16S-23S rDNA interspace [IS]-region-based profiling method (IS-Pro). The histology suggested bacterial colonization in the skin and in the peri-implant bone. FISH confirmed the localization of and coagulase-negative staphylococci in the skin. Ten articles (54 implants, 47 patients) met the inclusion criteria for the literature search. The analyzed samples were either BAHS (35 implants) or bone-anchored aural epitheses (19 implants) between 2 weeks and 8 years. The main reasons for elective removal were nonuse/changes in treatment, pain, or skin reactions. Most samples were evaluated using histology, demonstrating osseointegration, but with the absence of bone under the implants' proximal flange. Taken together, the literature and this case report show clear evidence of osseointegration, despite prominent complications. Nevertheless, despite implant osseointegration, chronic pain related to the BAHS may be associated with a chronic bacterial infection and raised inflammatory response in the absence of macroscopic signs of infection. It is suggested that a multimodal analysis of peri-implant health provides possibilities for device improvements and to guide diagnostic and therapeutic strategies to alleviate the impact of complications.
Topics: Bone-Anchored Prosthesis; Hearing; Hearing Aids; Humans; In Situ Hybridization, Fluorescence; Inflammation; Pain; Staphylococcus aureus; X-Ray Microtomography
PubMed: 33859952
DOI: 10.3389/fcimb.2021.640899 -
Nutrients Aug 2017The mechanisms behind the efficacy of exclusive enteral nutrition (EEN) in Crohn's disease (CD) remain poorly understood, despite the high rate of treatment response.... (Review)
Review
The mechanisms behind the efficacy of exclusive enteral nutrition (EEN) in Crohn's disease (CD) remain poorly understood, despite the high rate of treatment response. Evidence accumulated in the last 20 years suggests that a positive shift of the disrupted microbiota is one of the treatment effects. The purpose of this study was to critically review and summarize data reporting the microbiological effects of EEN in patients with CD. Fourteen studies were considered in the review, overall involving 216 CD patients on EEN. The studies were heterogeneous in methods of microbiota analysis and exclusion criteria. The most frequently reported effect of EEN was a reduction in microbiota diversity, reversible when patients returned to a normal diet. The effect of EEN on specific bacteria was very variable in the different studies, partially due to methodological limitations of the mentioned studies. The EEN seem to induce some metabolomic changes, which are different in long-term responder patients compared to patients that relapse earlier. Bacterial changes can be relevant to explaining the efficacy of EEN; however, microbiological data obtained from rigorously performed studies and derived from last generation techniques are largely inconsistent.
Topics: Bacteria; Crohn Disease; Enteral Nutrition; Gastrointestinal Microbiome; Humans; Intestines; Ribotyping; Treatment Outcome
PubMed: 28777338
DOI: 10.3390/nu9080832 -
Acta Dermato-venereologica Jan 2019The immune mechanisms involved in atopic dermatitis (AD) are complex and little is known about the possible role of the gut microbiota in the aetiopathogenesis of AD. A...
The immune mechanisms involved in atopic dermatitis (AD) are complex and little is known about the possible role of the gut microbiota in the aetiopathogenesis of AD. A systematic review of the literature was performed according to PRISMA guidelines, and included 44 of 2,199 studies (26 observational and 18 interventional studies). Detection of gut microbiota was performed by either 16s rRNA PCR, or by culture. Observational studies were diverse regarding the age of study participants and the bacterial species investigated. Overall, the results were conflicting with regard to diversity of the gut microbiota, specific bacterial colonization, and subsequent risk of AD. Nearly half of the included interventional studies showed that an altered gut microbial colonization due to use of probiotics had a positive effect on the severity of AD. The remaining studies did not show an effect of probiotics on the severity of AD despite an alteration in the gut microbial composition. The role of the gut microbiome for the onset and severity of pre-existing AD remains controversial.
Topics: Bacteria; Dermatitis, Atopic; Gastrointestinal Microbiome; Gastrointestinal Tract; Host-Pathogen Interactions; Humans; Probiotics; Ribotyping; Risk Factors; Severity of Illness Index
PubMed: 30085318
DOI: 10.2340/00015555-3008 -
Anaerobe Apr 2020Clostridioides difficile typing is invaluable for the investigation of both institution-specific outbreaks as well as national surveillance. While the epidemic ribotype...
Clostridioides difficile typing is invaluable for the investigation of both institution-specific outbreaks as well as national surveillance. While the epidemic ribotype 027 (RT027) has received a significant amount of resources and attention, ribotype 106 (RT106) has become more prevalent throughout the past decade. The purpose of this systematic review was to comprehensively summarize the genetic determinants, antimicrobial susceptibility, epidemiology, and clinical outcomes of infection caused by RT106. A total of 68 articles published between 1999 and 2019 were identified as relevant to this review. Although initially identified in the United Kingdom in 1999, RT106 is now found worldwide and became the most prevalent strain in the United States in 2016. Current data indicate that RT106 harbors the tcdA and tcdB genes, lacks binary toxin genes, and does not contain any deletions in the tcdC gene, which differentiates it from other epidemic strains, including ribotypes 027 and 078. Interestingly, RT106 produces more spores than other strains, including RT027. Overall, RT106 is highly resistant to erythromycin, clindamycin, fluoroquinolones, and third-generation cephalosporins. However, the MIC in most studies are one to two fold dilutions below the epidemiologic cut-off values of metronidazole and vancomycin, suggesting both are acceptable treatment options from an in vitro perspective. The few clinical outcomes studies available concluded that RT106 causes less severe disease than RT027, but patients were significantly more likely to experience multiple CDI relapses when infected with a RT106 strain. Specific areas warranting future study include potential survival advantages provided by genetic elements as well as a more robust investigation of clinical outcomes associated with RT106.
Topics: Anti-Bacterial Agents; Clostridioides difficile; Clostridium Infections; Genes, Bacterial; Humans; Microbial Sensitivity Tests; Public Health Surveillance; Ribotyping; Spores, Bacterial; Virulence
PubMed: 32007682
DOI: 10.1016/j.anaerobe.2019.102142