Toxizität lokaler Antiseptika auf Chondrozyten in vitro

Tolerability of N-chlorotaurine in comparison with routinely used antiseptics: an in vitro study on chondrocytes

BACKGROUND

Currently, povidone-iodine (PVP-I) and hydrogen peroxide (H2O2) are frequently used antiseptics in joint infections, but the cytotoxic effects of these solutions are already reported. N-chlorotaurine (NCT) shows a broad-spectrum bactericidal activity and is well tolerated in various tissues, but its effect on human chondrocytes is unknown. The purpose of this study was to assess the cytotoxic effect of NCT, PVP-I, and H2O2 on human chondrocytes compared to a control group in an in vitro setting to get first indications if NCT might be a promising antiseptic in the treatment of septic joint infections for the future.

MATERIAL AND METHODS

Chondrocytes extracted from human cartilage were incubated with various concentrations of NCT, PVP-I, and H2O2 for 5 and 30 min respectively. EZ4U cell viability kit was used according to the manufacturer's recommendations determining cell viability. To assess cell viability based on their nuclear morphology, cells were stained with acridine-orange and identified under the fluorescence microscope.

RESULTS

EZ4U kit showed after 5 and 30 min of incubation a significant decrease in cell viability at NCT 1%, NCT 0.1%, PVP-I, and H2O2, but not for NCT 0.001% and NCT 0.01%. Acridine-orange staining likewise presented a significant decrease in vital cells for all tested solutions except NCT 0.001% and NCT 0.01% after 5 and 30 min of incubation.

CONCLUSION

Our results demonstrate that NCT is well tolerated by chondrocytes in vitro at the tested lower NCT concentrations 0.01% and 0.001% in contrast to the higher NCT concentrations 1% and 0.1%, PVP-I (1.1%), and H2O2 (3%), for which a significant decrease in cell viability was detected. Considering that the in vivo tolerability is usually significantly higher, our findings could be an indication that cartilage tissue in vivo would tolerate the already clinically used 1% NCT solution. In combination with the broad-spectrum bactericidal activity, NCT may be a promising antiseptic for the treatment of septic joint infections.

[Antiseptics in otorhinolaryngology-a substance overview]

For preoperative skin antisepsis, alcohol-containing iodine solutions and octenidine are suitable. For wound antisepsis, polyhexanide and hypochlorous acid (HOCL) are also available, but only PVP-iodine and HOCL can be applied to cartilage. Chlorhexidine should only be used as mouth- and bodywash for Staphylococcus aureus (MRSA) decolonization. For the many other throat antiseptics, evidence of clinical efficacy is lacking. For decolonization of the nares, polyhexanide and octenidine are available as nasal gels, but these are inferior to mupirocin for MRSA decolonization. PVP-iodine and HOCL are safe to use for nasal irrigation, but only HOCL has proven effective to improve symptoms of chronic rhinosinusitis. All antiseptics exhibit a certain ototoxicity. With an intact eardrum, acetic acid-containing eardrops can be used to prevent and treat external otitis and myringitis. When the eardrum is perforated, only alcohol-free PVP-iodine and HOCL may be used.

The value of sequential application of hydrogen peroxide, povidone-iodine and physiological saline in reducing postoperative infections after total knee arthroplasty: A prospective, randomized, controlled study

BACKGROUND

Currently, in the field of total joint arthroplasty (TJA), there are no studies that have demonstrated the value of the sequential application of hydrogen peroxide, povidone-iodine, and physiological saline during the surgical procedure in decreasing postoperative infections in total knee arthroplasty (TKA), and in decreasing the incidence of periprosthetic joint infections (PJI) in particular. This study aimed to assess the efficacy of the sequential application of hydrogen peroxide, povidone-iodine, and physiological saline in reducing postoperative infections in TKA.

METHODS

The study prospectively included 4743 patients, with Group A (2371, 49.9%) receiving sequential intraoperative application of hydrogen peroxide, povidone-iodine, and physiological saline irrigation of the incision, and Group B (2372, 50.1%) receiving intraoperative application of physiological saline irrigation of the incision only, to collect the patients' baseline data and clinical characteristics, and to statistically assess the incidence of superficial infections and the PJI during the follow up period to evaluate the clinical value of the study.

RESULTS

The baseline levels of patients in Groups A and B were comparable. There were 132 (2.8%) lost visits during the study period. The incidence of superficial infections within 30 days after surgery was 0.22% in Group A and 1.17% in Group B, the difference between the two groups was statistically significant (P = 0.007). The incidence of PJI was 0.17% in Group A and 1.26% in Group B, the difference between the two groups was statistically significant (P = 0.0121).

CONCLUSION

Sequential application of hydrogen peroxide, povidone-iodine, and physiological saline to irrigate incision in TKA can significantly reduce the incidence of postoperative superficial infections and PJI. The scientific and rational application of this therapy intraoperatively greatly reduces the incidence of PJI and postoperative superficial infections, which is of great benefit to the patient's prognosis.

Chondrotoxic effects of tranexamic acid and povidone-iodine on the articular cartilage of rabbits

PURPOSE

To evaluate the chondrotoxic effects of intra-articular use of TXA 20 mg/kg and/or 0.35% PVPI on knee joint cartilage in an experimental model of rabbits.

METHODS

Forty-four male New Zealand adult rabbits were randomly assigned to four groups (control, tranexamic acid (TXA), povidone-iodine (PVPI), and PVPI + TXA). The knee joint cartilage was accessed through an arthrotomy and exposed to physiological saline SF 0.9% (control group), TXA, PVPI, and PVPI followed by TXA. Sixty days after surgical procedure, the animals were sacrificed and osteochondral specimens of the distal femur were obtained. Histological sections of cartilage from this area were stained with hematoxylin/eosin and toluidine blue. The following cartilage parameters were evaluated by the Mankin histological/histochemical grading system: structure, cellularity, glycosaminoglycan content in the extracellular matrix, and integrity of the tidemark.

RESULTS

The isolated use of PVPI causes statistically significant changes in cartilage cellularity (p-value = 0.005) and decrease glycosaminoglycan content (p = 0.001), whereas the isolated use of TXA decreased significantly the glycosaminoglycan content (p = 0.031). The sequential use of PVPI + TXA causes more pronounced alterations in the structure (p = 0.039) and cellularity (p = 0.002) and decreased content of glycosaminoglycans (p < 0.001) all with statistical significance.

CONCLUSION

Data suggest that intra-articular use of tranexamic acid 20 mg/kg and intraoperative lavage with 0.35% povidone-iodine solution for three min are toxic to the articular cartilage of the knee in an experimental in vivo study in rabbits.

Cell Toxicity Study of Antiseptic Solutions Containing Povidone–Iodine and Hydrogen Peroxide

The increasing incidence of periprosthetic joint infections (PJIs) has led to a growing interest in developing strategies to prevent and treat this severe complication. The surgical site’s application of antiseptic solutions to eliminate contaminating bacteria and eradicate the bacterial biofilm has been increasing over time. Even though it has been proven that combining antimicrobials could enhance their activities and help overcome acquired microbial resistance related to the topical use of antibiotics, the toxicity of integrated solutions is not well described. This study aimed to evaluate the cytotoxicity of solutions containing povidone–iodine (PI) and hydrogen peroxide (H2O2), alone or in combination, after 1.3 and 5 min of exposure. Chondrocytes, tenocytes, and fibroblast-like synoviocytes were used for cytotoxicity analysis. Trypan blue stain (0.4% in PBS) was applied to evaluate the dead cells. All solutions tested showed a progressive increase in toxicity as exposure time increased except for PI at 0.3%, which exhibited the lowest toxicity. The combined solutions reported a reduced cellular killing at 3 and 5 min than H2O2 at equal concentrations, similar results to PI solutions.

Sodium hypochlorite is more effective than chlorhexidine for eradication of bacterial biofilm of staphylococci and Pseudomonas aeruginosa

PURPOSE

Periprosthetic infection is a common reason for surgical revision. Given the increasing resistance of bacteria to antibiotics (e.g., VRE, 4-MRGN) local antiseptic treatment is gaining in importance. However, no standard guideline-based treatment recommendation is yet available. The aim of this study was to investigate the effectiveness of sodium hypochlorite and chlorhexidine against bacterial biofilms. Furthermore, the toxicity of both antiseptics towards human chondrocytes was examined.

METHODS

Human chondrocytes were isolated, cultivated and treated with sodium hypochlorite and chlorhexidine. The viability of cultures was assessed by determination of cell count, XTT and MTT ELISAs, and fluorescent staining with propidium iodide. Bacterial strains of Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa were added to liquid media and incubated overnight. After determination of bacterial concentrations polyethylene (PE) devices were inoculated with bacteria for 48 h until biofilms formed. The devices were then washed, treated with antiseptics for 2 and 5 min and subsequently spread on agar plates.

RESULTS

Sodium hypochlorite is more effective than chlorhexidine in penetrating biofilms of S. aureus, S. epidermidis and P. aeruginosa. Both antiseptics are chondrotoxic, but sodium hypochlorite damages human chondrocytes less than chlorhexidine in vitro.

CONCLUSIONS

The findings confirm the effectiveness of sodium hypochlorite and chlorhexidine against bacterial biofilms. Both antiseptics can be recommended for the treatment of periprosthetic infections. The toxic effects of sodium hypochlorite and chlorhexidine towards chondrocytes may mean there is a risk of damage to cartilage tissue.

LEVEL OF EVIDENCE

Controlled experimental study.

Intraoperative Use of Betadine Irrigation is Associated With a 9-Fold Increased Likelihood of Penile Prosthesis Infection: Results From a Retrospective Case-Control Study

Introduction

Infection remains a persistent complication of penile prosthesis (PP) surgery. Despite popularity of Mulcahy’s PP washout protocol, Betadine has known tissue toxicity.

Aim

We evaluated PP infection rate based on the type of intraoperative irrigation used, ½ strength Betadine vs vancomycin/gentamicin.

Methods

We reviewed a prospective database of men undergoing primary, revision, and salvage PPs. No other changes to operative or perioperative techniques occurred after the change in irrigation solution. Univariate and logistic regression analyses were used to evaluate differences in infection rate with use of Betadine vs vancomycin/gentamicin irrigation. Potential confounders were reviewed.

Main Outcome Measure

The primary outcome was rate of PP infection before and after change of intraoperative irrigation.

Results

From 2014 to 2018, 217 patients underwent PP placement at our institution by a single surgeon; of whom, 21 (9.7%) experienced an infection (primary = 10 [7.1%], revision = 11 [17.19%], salvage = 0 [0%]). Overall, 152 (70%) received irrigation with Betadine and 65 (30%) with Vancomycin/Gentamicin. Univariate analysis demonstrated significantly increased infection rates with Betadine irrigation (odds ratio [OR]: 4.64, P = .006) and with revision surgery (OR: 2.68, P = .02). Significance of increased infection rate with Betadine was maintained (OR: 9.3; P = .025) after controlling for age, body mass index, Charlson comorbidity index, smoking, diabetes, primary vs revision/salvage, prior penile surgery, use of ectopic reservoir, and adjunctive glanulopexy.

Conclusions

Changing from intraoperative Betadine to vancomycin/gentamicin solution dramatically reduced infection rates among men undergoing PP placement in both primary and revision cases. We hypothesize that differences in infection rate may relate to the relative toxicity or non-sterile nature of Betadine.

Manka MG, Yang D, Andrews J, et al. Intraoperative Use of Betadine Irrigation is Associated With a 9-Fold Increased Likelihood of Penile Prosthesis Infection: Results From a Retrospective Case-Control Study. Sex Med 2020;8:422–427.

The Use of Antiseptic Solutions in the Prevention and Management of Penile Prosthesis Infections: A Review of the Cytotoxic and Microbiological Effects of Common Irrigation Solutions

INTRODUCTION

The Mulcahy salvage fundamentally altered the management of penile prosthesis infections (PPI). Central to this procedure is a sequence of antiseptic irrigations that aims to remove and eradicate pathogenic microflora from the infected field, thus preparing for immediate reimplantation. The antiseptic solutions and their respective concentrations, however, have never been evaluated for efficacy.

AIM

This review critically examines 3 commonly used antiseptic irrigation solutions (povidone-iodine [PVI], hydrogen peroxide [H₂O₂], and chlorhexidine gluconate [CHG]) in terms of their antimicrobial activity, cytotoxicity, and clinical use.

METHODS

A PubMed literature review was performed on articles published between 2003 and 2018. Both preclinical as well as clinical studies from various surgical disciplines were included in this review.

MAIN OUTCOME MEASURE

The original salvage protocol selected for irrigation solutions at concentrations that are likely detrimental to native tissue.

RESULTS

All 3 agents demonstrate in vitro cytotoxic effects at subclinical concentrations, but H₂O₂ is associated with the most significant deleterious properties. It does not seem to broaden antimicrobial coverage beyond what is covered by PVI. Dilute PVI (0.35-3.5% with exposure time of at least 3 minutes) possesses the most robust clinical evidence as an intraoperative adjunct, reducing the incidence of postoperative infectious complications. chlorhexidine gluconate is a promising new agent but lacks clinical data.

CLINICAL IMPLICATION

Improvements in the salvage protocol are warranted based on current evidence. Careful selection of lavage solution and usage of the lowest necessary concentration will help achieve desired antimicrobial activity while avoiding native tissue cytotoxicity. Strength and limitation: The study is limited by its retrospective nature, and the heterogeneity of literature reviewed precluded a formal meta-analysis. Furthermore, future studies will need to address the roles of normal saline and antibiotic irrigations as intraoperative adjuncts for infection prevention.

CONCLUSION

Diluted PVI (0.35-3.5% for 3 minutes) may be beneficial in the prevention of PPI. Evidence supports its use both in the setting of primary implantation as well as salvage of infected hardware. An improved, evidence-based protocol may increase positive outcomes of urologic prosthetic surgery. Pan S, Rodriguez D, Thirumavalavan N, et al. The Use of Antiseptic Solutions in the Prevention and Management of Penile Prosthesis Infections: A Review of the Cytotoxic and Microbiological Effects of Common Irrigation Solutions. J Sex Med 2019;16:781-790.

The Effect of Antiseptics on Adipose-Derived Stem Cells

BACKGROUND

Although chemical antiseptics are the most basic measure to control wound infection and frequently come into contact with subcutaneous adipose tissue, no studies have evaluated their toxicity on adipose tissue and its cell fractions. In the present study, the effects of five different antiseptics on adipose-derived stem cells were evaluated.

METHODS

Human adipose-derived stem cells were harvested from healthy donors. Adipose-derived stem cell viability was measured after treatment with different concentrations of antiseptics over 5 days. Furthermore, the effect on the proliferation, adipogenic differentiation, and apoptosis/necrosis of adipose-derived stem cells was analyzed. Finally, the mRNA expression of the stem cell markers CD29, CD34, CD73, CD90, and CD105 was detected.

RESULTS

Octenisept and Betaisodona significantly reduced cell proliferation and differentiation and led to considerable adipose-derived stem cell necrosis. Octenisept decreased stem cell viability at the lowest concentrations tested, and all stem cell markers were down-regulated by Octeniseptr and Betaisodona. Lavasept and Prontosan both led to reduced stem cell viability, proliferation, and differentiation, and increased apoptosis/necrosis, although the effects were less pronounced compared with Octenisept and Betaisodona. Adipose-derived stem cells survived treatment with mafenide acetate even at high concentrations, and mafenide acetate showed minimal negative effects on their proliferation, adipogenic differentiation, cell death, and stem cell marker expression.

CONCLUSIONS

Mafenide acetate may be regarded as a feasible antiseptic for the treatment of wounds with exposed adipose tissue because of its low adipose-derived stem cell toxicity. Lavasept and Prontosan are possible alternatives to mafenide acetate. Octenisept and Betaisodona, by contrast, may be used only in highly diluted solutions.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

Human osteoblast damage after antiseptic treatment

PURPOSE

Antiseptics are powerful medical agents used for wound treatment and decontamination and have a high potential for defeating joint infections in septic surgery. Both chlorhexidine and polyhexanide are frequently used in clinical practice and have a broad antimicrobial range, but their effect on human osteoblasts has not been sufficiently studied. Our objective was to investigate the toxic effects of polyhexanide and chlorhexidine on human osteoblasts in vitro to evaluate their clinical applicability in septic surgery.

METHODS

We isolated and cultivated human osteoblasts in vitro and assayed the toxic effects of chlorhexidine 0.1% and polyhexanide 0.04%, concentrations commonly applied in clinical practice. Toxicity analysis was performed by visualisation of cell structure, lactate dehydrogenase (LDH) activity and evaluation of vital cells. Toxicity was evaluated by microscopic inspection of cell morphology, trypan blue staining and determination of LDH release.

RESULTS

Damaged cell structure could be shown by microscopy. Both antiseptics promoted LDH activity after incubation with osteoblasts. The evaluation of vital osteoblasts showed a significant decrease of vital cells.

CONCLUSIONS

Both antiseptics induced significant cell death of osteoblasts at optimum exposure. We therefore recommend cautious use of polyhexanide and chlorhexidine in septic surgery to avoid severe osteoblast toxicity.

Polyhexanide and hydrogen peroxide inhibit proteoglycan synthesis of human chondrocytes

The use of local antiseptics is a common method in septic joint surgery. We tested polyhexanide and hydrogen peroxide, two of the most frequently used antiseptics with high efficacy and low toxicity. The purpose of this study was to evaluate the effects of both antiseptics on the extracellular cartilaginous matrix synthesis of human chondrocytes. Chondrocytes were isolated from donated human knee joints, embedded in alginate beads, and incubated for 10 and 30 minutes with polyhexanide (0.04%), hydrogen peroxide (3%), or phosphate-buffered saline (PBS) for control. Cartilaginous matrix production was quantified through light microscopic analysis of Alcian blue staining. Cell number and morphology were detected by histological analysis. Chondrocytes showed a decreased intensity of blue colouring after antiseptic treatment versus PBS. In contrast to that, neither the cell number per view field nor the cell morphology differed between the groups. Polyhexanide has more toxic potential than hydrogen peroxide. Based on the fact that the cell number and morphology was not altered by the substances at the examined concentrations, the lower intensity of Alcian blue staining of treated chondrocytes indicates a decreased cartilage-specific matrix synthesis by polyhexanide more than by hydrogen peroxide and control.

Incorporation of bioactive polyvinylpyrrolidone-iodine within bilayered collagen scaffolds enhances the differentiation and subchondral osteogenesis of mesenchymal stem cells

Polyvinylpyrrolidone-iodine (Povidone-iodine, PVP-I) is widely used as an antiseptic agent for lavation during joint surgery; however, the biological effects of PVP-I on cells from joint tissue are unknown. This study examined the biocompatibility and biological effects of PVP-I on cells from joint tissue, with the aim of optimizing cell-scaffold based joint repair. Cells from joint tissue, including cartilage derived progenitor cells (CPC), subchondral bone derived osteoblast and bone marrow derived mesenchymal stem cells (BM-MSC) were isolated. The concentration-dependent effects of PVP-I on cell proliferation, migration and differentiation were evaluated. Additionally, the efficacy and mechanism of a PVP-I loaded bilayer collagen scaffold for osteochondral defect repair was investigated in a rabbit model. A micromolar concentration of PVP-I was found not to affect cell proliferation, CPC migration or extracellular matrix production. Interestingly, micromolar concentrations of PVP-I promote osteogenic differentiation of BM-MSC, as evidenced by up-regulation of RUNX2 and Osteocalcin gene expression, as well as increased mineralization on the three-dimensional scaffold. PVP-I treatment of collagen scaffolds significantly increased fibronectin binding onto the scaffold surface and collagen type I protein synthesis of cultured BM-MSC. Implantation of PVP-I treated collagen scaffolds into rabbit osteochondral defect significantly enhanced subchondral bone regeneration at 6 weeks post-surgery compared with the scaffold alone (subchondral bone histological score of 8.80±1.64 vs. 3.8±2.19, p<0.05). The biocompatibility and pro-osteogenic activity of PVP-I on the cells from joint tissue and the enhanced subchondral bone formation in PVP-I treated scaffolds would thus indicate the potential of PVP-I for osteochondral defect repair.

Deleterious effects of diluted povidone-iodine on articular cartilage

A recent study has suggested that irrigation with povidone-iodine solution after knee arthroplasty significantly decreases rates of post-operative surgical site infection. However, there is only limited knowledge of potential chondrotoxic effects on the residual cartilage in patients with partial knee arthroplasties or unresurfaced patella in total knee arthroplasty. Macroscopically normal bovine cartilage explants (n=42) were exposed to different povidone-iodine concentrations for 1, 3 or 6 min, as well as saline control. The viability of superficial chondrocytes was measured by a Live/Dead cytotoxicity assay. Chondrotoxicity correlated positively with the length of exposure, regardless of the concentration. The extent of superficial chondrocyte death was significantly greater at higher concentrations of povidone-iodine solutions. 0.35% povidone-iodine solution was the least chondrotoxic of all concentrations, but still reduced cell viability significantly if applied for longer than 1 min. Our data suggest that povidone-iodine solution at all tested concentrations has a pronounced chondrotoxic effect on the superficial cartilage layer when used for time periods longer than 1 min.

[Joint infections. Known facts and new trends]

Acute septic arthritis is a surgical emergency because rapid septic destruction of articular cartilage can lead to impairment or even loss of joint function. Diagnosis consists of patient history, clinical examination, laboratory results, (sonography- guided) joint aspiration and radiography. Emergency therapy is based on arthroscopic or open joint debridement and lavage combined with systemic antibiotic therapy. No data are available for the recommendation of local antibiotics but antiseptic solutions are not recommended because of cartilage damage. New trends in diagnostics are positron emission tomography/computed tomography (PET/CT), urine sticks for analysis of joint fluid and molecular pathology. Chronic joint empyema is more diagnostically demanding and is difficult to treat. In cases of necrotic and infected articular cartilage, joint resection has to be performed for quiescence of infection. Options following successful treatment of empyema are arthroplasty, arthrodesis or permanent resection.

Toxicity of antiseptics against chondrocytes: what is best for the cartilage in septic joint surgery?

In septic joint surgery, the most frequently used antiseptics are polyhexanide, hydrogen peroxide and taurolidine. The aim of this study was to examine the effects of these antiseptics on viability of human chondrocytes. Our hypothesis was that antiseptics and supplemental irrigation with sodium chloride lavage are less toxic on human chondrocytes than treatment with antiseptics only. Primary human chondrocytes were isolated and cultured from six donated human knee joints. Polyhexanide, hydrogen peroxide or taurolidine were added to the cultures. Toxicity analysis was performed by visualisation of cell structure using light microscopy and LDH activity. The determination of vital cells and total cell numbers of chondrocytes treated with antiseptics partly followed by irrigation with sodium chloride solution was performed by using Casy Cell-Counter. Light microscopic data revealed a defect in cell structure after addition of antiseptics. We showed a significant increase of LDH enzyme activity after the treatment with polyhexanide or taurolidine. After treatment with antiseptics followed by sodium chloride solution a significant increase of vital and total cell numbers resulted in comparison with the chondrocytes that were only treated with antiseptics. The data show that treatment with polyhexanid, hydrogen peroxide or taurolidine induces cell death of human chondroctes in vitro. The application of sodium chloride solution after the treatment with polyhexanide and hydrogen peroxide possibly has a protective effect on chondrocyte viability.

Toxicity of polyhexanide and hydrogen peroxide on human chondrocytes in vitro

The treatment of acute joint infections has an important impact on long-term outcome and remains an unsolved problem. The most frequent bacteria are staphylococci, streptococci, and gram-negative bacteria. In septic surgery, polyhexanide and hydrogen peroxide are the most frequently used local antiseptics. The aim of this study was to examine the hypothesis that antiseptics induce cell death of human chondrocytes after a short incubation time.Human chondrocytes were treated with different concentrations of polyhexanide and hydrogen peroxide. Toxicity analysis was determined by visualization of cell structure using light microscopy, lactate dehydrogenase release, and determination of living and total cell numbers after addition of polyhexanide and hydrogen peroxide. Light microscopic data revealed a defect cell structure after addition of both antiseptics. Lactate dehydrogenase activity showed a significant increase of enzyme expression after a short incubation with polyhexanide. The determination of vital chondrocytes showed a significant decrease of vital and total cell numbers after addition with polyhexanide and hydrogen peroxide.Both antiseptic solutions induce significant cell death of human chondrocytes after a short incubation time. Polyhexanide possibly has more toxic potential than hydrogen peroxide against human chondrocytes after an application >15 minutes. Therefore, both substances should only be applied for a short time (<15 minutes) and the joint irrigated to wash out the antiseptic substance prior to wound closure.