ABSTRACT
OBJECTIVE: The timely management of vascular graft/endograft infection (VGEI) is crucial to a favourable outcome, yet can be challenging as there is no validated gold standard diagnostic test. Recently, a new case definition has been proposed by the Management of Aortic Graft Infection Collaboration (MAGIC) to close the diagnostic gap. The aim of this study was to validate the MAGIC criteria as a suggested diagnostic standard for the diagnosis of suspected VGEI in the prospective Vascular Graft Cohort study (VASGRA). METHODS: VASGRA is an open, prospective, observational cohort study. Prospective participants in VASGRA between 2013 and 2019 were included (257 patients; 137 with VGEI). The accuracy of the MAGIC criteria for a diagnosis of VGEI was evaluated retrospectively by calculating the sensitivity and specificity vs. the consensually adjudicated VASGRA infection status. RESULTS: The VASGRA cohort categorised 137 (53.3%) patients as "diseased" and 120 patients as "not diseased"; using the MAGIC criteria, 183/257 (71.2%) patients were considered to be "diseased". Thus, for the MAGIC criteria, a sensitivity of 99% (95% confidence interval [CI] 96-100) and a specificity of 61% (95% CI 52-70) were calculated. Considering suspected VGEI according to the MAGIC criteria as "not diseased" achieved congruent assessments of the VASGRA team and the MAGIC criteria, with a sensitivity of 93% and a specificity of 93%. The accuracy of the MAGIC criteria for the different graft locations were also compared. If the suspected VGEIs were assigned to the "not diseased" group, VGEIs of the thoracic aorta seemed to have a poorer sensitivity (86%; 95% CI 73-95) than the other graft locations. CONCLUSION: The current MAGIC criteria offer good sensitivity and specificity in the context of true infections but a reduced specificity for a possible VGEI.
Subject(s)
Blood Vessel Prosthesis/adverse effects , Infections/diagnosis , Transplants/microbiology , Vascular Grafting/adverse effects , Aged , Aorta, Abdominal , Aorta, Thoracic , Blood Culture , Blood Vessel Prosthesis/microbiology , C-Reactive Protein , Female , Humans , Infections/blood , Infections/microbiology , Leukocyte Count , Male , Middle Aged , Observational Studies as Topic , Positron Emission Tomography Computed Tomography , Prospective Studies , Retrospective Studies , Sensitivity and Specificity , Serologic TestsABSTRACT
PURPOSE: The aim of the study is to determine the risk of contamination in the cartilage graft materials prepared on the swester table and those prepared in a sterile package, and to reveal a more reliable method by performing the microbiological examination of these materials. METHODS: Cartilages removed from the nasal septum were divided into four pieces. The first part (Sample A) was directly placed into the medium. Sample B was prepared by being crushed in a sterile package. Sample C was prepared on the auxiliary swester table, and Sample D was prepared on the main swester table actively used by surgery team. All samples were transferred in a 1 ml brain heart(BH) liquid medium. From each BH medium, 100 µl culture was performed on blood agar, eosin-methylene blue-lactose-sucrose agar and chocolate agar. RESULTS: Bacterial growth was detected in 2 of the samples A, in 4 of the samples B, in 24 of the samples C, and in 36 of the samples D. The number of patients with bacterial growth in the samples C and/or D despite no growth in the sample B was 35. When the samples A/B and C/D were compared in terms of bacterial growth, a significant difference was found in all matchings (p < 0.001 for all comparisons). CONCLUSION: These findings showed that preparation of the cartilage grafts on the swester table was extremely risky for microbiological contamination. Arslan and his colleagues suggest that preparing a graft material in a sterile package is extremely simple, cheap, and it also reduces contamination risk significantly.
Subject(s)
Cartilage , Equipment Contamination/prevention & control , Postoperative Complications/prevention & control , Rhinoplasty , Transplants/microbiology , Adult , Bacteria/isolation & purification , Cartilage/microbiology , Cartilage/transplantation , Female , Humans , Male , Nasal Septum/surgery , Plastic Surgery Procedures/adverse effects , Plastic Surgery Procedures/methods , Rhinoplasty/adverse effects , Rhinoplasty/methods , Tissue and Organ Harvesting/methodsABSTRACT
BACKGROUND: Selective digestive decontamination is commonly used to decrease lumenal bacterial flora. Preoperative bowel decontamination may be associated with a lower wound infection rate but has not been shown to decrease risk of intra-abdominal abscess or lower leak rate for enteric anastomoses. Alternatively, the decontamination disrupts the normal flora of the gastrointestinal tract and may affect normal physiology, including immunologic function. This study reports complication rates of an intestine transplant program that has never used bowel decontamination. METHODS: All adult patients who underwent intestine transplant from 2003 to 2015 at a single center were reviewed. Posttransplant complications included intra-abdominal abscess, enteric fistula, and leak from the enteric anastomosis. Viral, fungal, and bacterial infections in the first year after transplant are reported. RESULTS: There were 184 adult patients who underwent deceased donor intestine transplant during the study period. Among these patients, 30% developed an infected postoperative fluid collection, 4 developed an enteric fistula (2%), and 16 had an enteric or anastomotic leak (8%). The rate of any bacterial infection was 91% in the first year, with a wound infection rate of 25%. Fungal infection occurred in 47% of patients. Rejection rates were 55% at 1 y for isolated intestine patients and 17% for multivisceral (liver inclusive) patients. CONCLUSIONS: Among this population of intestine transplant patients in which no bowel decontamination was used, rates of surgical complications, infections, and rejection were similar to those reported by other centers. Bowel decontamination provides no identifiable benefit in intestine transplantation.
Subject(s)
Gastrointestinal Microbiome/immunology , Graft Rejection/epidemiology , Intestinal Diseases/surgery , Intestines/transplantation , Postoperative Complications/epidemiology , Preoperative Care/methods , Abdominal Abscess/epidemiology , Abdominal Abscess/immunology , Abdominal Abscess/microbiology , Adult , Aged , Anastomosis, Surgical/adverse effects , Female , Graft Rejection/immunology , Graft Rejection/microbiology , Humans , Intestinal Fistula/epidemiology , Intestinal Fistula/immunology , Intestinal Fistula/microbiology , Intestines/immunology , Intestines/microbiology , Male , Middle Aged , Postoperative Complications/immunology , Postoperative Complications/microbiology , Preoperative Care/adverse effects , Retrospective Studies , Transplants/microbiology , Treatment Outcome , Young AdultABSTRACT
Invasive fusariosis in solid organ transplant is uncommon and usually presents as localized infection with favorable outcomes compared to hematologic malignancies or bone marrow transplants. We report the first case of Fusarium osteomyelitis in a patient following multi-visceral transplant and review Fusarium in organ transplant recipients and Fusarium bone and joint infections. Our case underscores the importance of early recognition and multidisciplinary approach to treatment and highlights potential failure to eradicate with amphotericin B monotherapy.
Subject(s)
Amphotericin B/adverse effects , Fusariosis/diagnosis , Fusariosis/microbiology , Fusarium/isolation & purification , Osteomyelitis/microbiology , Abdomen/diagnostic imaging , Abdomen/microbiology , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Bone Marrow Transplantation/adverse effects , Fatal Outcome , Fusariosis/drug therapy , Fusarium/drug effects , Hematologic Neoplasms , Humans , Immunocompromised Host , Male , Middle Aged , Osteomyelitis/drug therapy , Osteomyelitis/etiology , Tomography, X-Ray Computed , Transplants/microbiology , Voriconazole/therapeutic useABSTRACT
PURPOSE: Why anterior cruciate ligament (ACL) autograft soaking in a 5 mg/ml vancomycin solution decreases the rate of infection has not been well-explained. One hypothesis is that grafts can be contaminated during harvesting and vancomycin eradicates the bacteria. The purpose of the present study is to assess how the vancomycin solution acts against ACL graft contamination during graft harvesting and preparation. METHODS: The study was carried out in three university hospitals over a period of 6 months. After sample size calculation, 50 patients were included in the study. Three samples were taken from each ACL graft. Sample 1 was obtained immediately after graft harvesting. After graft manipulation and preparation, the remaining tissue was divided into two parts. The raw sample was denominated sample 2 and sample 3 consisted of the rest of the remaining tissue that had been soaked in the vancomycin solution. All the cultures were incubated at 37 °C with 5% CO2 in agar plates for 7 days (aerobically) or 14 days (anaerobically) and inspected daily for microbial growth. Any bacterial growth and the number of colony forming units were reported. RESULTS: In seven cases (14%), either sample 1 or sample 2 was positive. In five of the cases (10%), only the sample after graft preparation was positive (sample 2). In two cases (4%), sample 1 and sample 2 were positive for the same bacteria. Isolated microorganisms corresponded to coagulase-negative staphylococci (CNS) and Propionibacterium acnes. No bacterial growth was observed in sample 3 (p < 0.001). Thus, none of those seven positive cases (0%) were positive after vancomycin soaking (p < 0.001). CONCLUSION: In the series, ACL graft harvesting and manipulation leads to bacterial contamination in 14% of the cases. This contamination is fully eradicated after soaking in the vancomycin solution in this series. LEVEL OF EVIDENCE: Level II.
Subject(s)
Anterior Cruciate Ligament/microbiology , Anterior Cruciate Ligament/surgery , Surgical Wound Infection/drug therapy , Transplants/microbiology , Transplants/surgery , Adolescent , Adult , Anterior Cruciate Ligament Injuries/surgery , Anterior Cruciate Ligament Reconstruction , Anti-Bacterial Agents/pharmacology , Female , Humans , Male , Transplantation, Autologous , Vancomycin/pharmacologyABSTRACT
INTRODUCTION: Contamination of the preservation solution may contribute to septic complications that can occur after transplantation and cause higher morbidity and mortality among recipients. The aim of this study was to determine potential donor-related predictors of positive microbiological findings in the preservation solution. DESIGN: We retrospectively studied 16 donor parameters on data from our center for microbiological findings in the preservation solution used in solid-organ recovery. From January 2008 through December 2011, 976 solid organs were transplanted, and in 167, the solution was positive for contaminants. RESULTS: The most frequently detected contaminant was coagulase-negative staphylococci. Only the donor leucocyte count (cutoff at 9.1 × 109/L) predicted positive microbiological findings in the preservation solution ( P = .0024). Multivariable regression analysis found that donor age, donor sex, intensive care unit stay, total number of organs recovered, and leucocyte count differentiated various categories of potentially pathogenic bacteria. CONCLUSION: Donor leucocyte count higher than 9.1 × 109/L predicts contamination of preservation solution.
Subject(s)
Cross Infection/etiology , Cross Infection/microbiology , Organ Preservation Solutions/adverse effects , Organ Preservation/adverse effects , Organ Transplantation/adverse effects , Transplants/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Load , Child , Child, Preschool , Colony Count, Microbial , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Organ Preservation/methods , Organ Transplantation/methods , Retrospective Studies , Young AdultABSTRACT
BACKGROUND: Potential organ donors may be admitted with an infection to an intensive care unit, or contract a nosocomial infection during their stay, increasing the risk of potential transmission to the recipient. Because of a lack of practice guidelines and large-scale data on this topic, we undertook a survey to assess the willingness of transplant infectious diseases (ID) physicians to accept such organs. METHODS: We performed a 10-question survey of ID providers from the American Society of Transplantation Infectious Disease Community of Practice to determine the scope of practice regarding acceptance of organs from donors with bloodstream infection, pneumonia, and influenza prior to organ procurement, as well as management of such infections following transplantation. RESULTS: Among 60 respondents to our survey, a majority indicated that organs would be accepted from donors bacteremic with streptococci (76%) or Enterobacteriaceae (73%) without evidence of drug resistance. Acceptance rates varied based on infecting organism, type of organ, and center size. Ten percent of respondents would accept an organ from a donor bacteremic with a carbapenem-resistant organism. Over 90% of respondents would accept an organ other than a lung from a donor with influenza on treatment, compared with 52% that would accept a lung in the same setting. CONCLUSIONS: This study is the first to our knowledge to survey transplant ID providers regarding acceptance of organs based on specific infections in the donor. These decisions are often based on limited published data and experience. Better characterization of the outcomes from donors with specific types of infection could lead to liberalization of organ acceptance practices across centers.
Subject(s)
Bacteremia/transmission , Candidemia/transmission , Cross Infection/transmission , Donor Selection , Influenza, Human/transmission , Pneumonia/microbiology , Transplants/microbiology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacteremia/drug therapy , Bacteremia/microbiology , Bacteria/isolation & purification , Candidemia/microbiology , Carbapenems/pharmacology , Carbapenems/therapeutic use , Clinical Decision-Making , Cross Infection/drug therapy , Cross Infection/microbiology , Drug Resistance, Bacterial , Humans , Influenza, Human/drug therapy , Influenza, Human/microbiology , Pneumonia/drug therapy , Practice Guidelines as Topic , Surveys and Questionnaires , Tissue DonorsABSTRACT
BACKGROUND: Timely diagnosis of invasive fungal infections (IFI) in renal transplant (RT) patients on immunosuppression is often difficult, jeopardizing their life and graft. We reported IFI and their causative fungal agents in post-RT patients. MATERIALS AND METHODS: This was a retrospective 6-year clinical study carried out from 2010 to 2015 on 1900 RT patients. Clinical data included patient-donor demographics, time to onset of infection, risk factors and graft function in terms of serum creatinine (SCr). To identify IFI, we examined bronchoalveolar lavage (BAL), blood, tissue, and wound swab samples by conventional mycological methods. RESULTS: IFI were diagnosed in 30 (1.56%) patients on triple immunosuppression, mainly males (n = 25) with mean age of 36.57 ± 11.9 years at 13.12 ± 18.35 months post-RT. Aspergillus species was identified in 11 BAL, one tissue, and one wound specimen each, 30.76% of these were fatal and 15.38% caused graft loss; Candida albicans was in nine BAL, four blood, two wound swab, and one tissue specimens, 25% of these were fatal and 25% had graft loss and one mucor in BAL which was fatal. Seven patients were diabetic, 10 had superadded cytomegalovirus infection, and 15 were anti-rejected. CONCLUSION: IFI are associated with increased morbidity and mortality in RT patients. Triple immunosuppression, broad spectrum antibiotics for ≥ two weeks, diabetes and superadded infection are added risks for these patients. Prevention, early diagnosis, and appropriate management are necessary to improve their prognosis.
Subject(s)
Amphotericin B/administration & dosage , Immunosuppression Therapy , Invasive Fungal Infections , Kidney Transplantation , Postoperative Complications , Transplants/microbiology , Adult , Antifungal Agents/administration & dosage , Aspergillus/isolation & purification , Candida albicans/isolation & purification , Female , Graft Survival , Humans , Immunosuppression Therapy/adverse effects , Immunosuppression Therapy/methods , India/epidemiology , Invasive Fungal Infections/diagnosis , Invasive Fungal Infections/drug therapy , Invasive Fungal Infections/etiology , Kidney Failure, Chronic/surgery , Kidney Transplantation/adverse effects , Kidney Transplantation/methods , Kidney Transplantation/mortality , Male , Middle Aged , Outcome Assessment, Health Care , Postoperative Complications/diagnosis , Postoperative Complications/drug therapy , Postoperative Complications/microbiology , Retrospective StudiesABSTRACT
Radiation sterilization eliminates microbiological infections but causes the degradation of the cell factor. The negative result of microbiological examination for tissue transplants is one of the conditions for approval for distribution in patients. The study attempts to verify impact of the presence of microbes onto material for transplant loss. In the 2011-2015 period, we analyzed 293 donors of skin and amnion. Microbiological sampling was performed. The total of 21 strains of bacteria, molds and fungi was identified in collected tissue. The widest spectrum of strains was found in skin (17), followed by amnia (8). The total number of positive findings was 147 and was again highest in skin (129), while the number of positive findings in amnia was 18 only. The general percentage of fungal infections was very low. The presence of fungal strains was only observed in allogeneic skin (2%). Large number of microorganisms isolated from the skin before sterilization was observed, so it seems impossible to use allogeneic intravital skin. However, the intravital application of allogeneic amnion obtained from cesarean section remains to be considered.
Subject(s)
Amnion/microbiology , Amnion/transplantation , Bacteria/isolation & purification , Bacterial Infections/etiology , Fungi/isolation & purification , Mycoses/etiology , Skin Transplantation/adverse effects , Skin/microbiology , Adult , Humans , Sterilization , Tissue Banks , Tissue Donors , Transplants/microbiologyABSTRACT
PURPOSE: The purpose of this study was to identify factors that increase the risk of vascular graft infections (VGI) in patients following abdominal or lower extremity revascularization surgery. DESIGN: Retrospective, descriptive study. METHODS: We reviewed the electronic health records of 223 patients who had undergone abdominal or lower extremity revascularization procedures from July 2012 to November 2014, looking for factors associated with VGI. We reviewed 28 preoperative, intraoperative, and post-operative factors. Descriptive statistics (mean, range, and standard deviation) were used to describe the sample; χ was used to determine correlations between the risk factors and subsequent VGIs. The level of significance was determined at P = .05, with a confidence level of 95%. RESULTS: We identified 33 cases of VGIs for the 223 charts reviewed, yielding an incidence rate of 15%. Seventeen of the 33 patients with VGI (51.5%) were male. The average age of patients who experienced VGI was 60.9 years (standard deviation, 12.2 years, range, 29-81 years). Preoperative factors that were shown to show statistical significance for the development of VGI were sequential procedures (P = .003), diabetes mellitus (P = .002), hemoglobin A1c more than 7.0 (P = .0002), blood glucose more than 180 mg/dL (P = .0006), and lack of mobility (0.0097). Intraoperative factors associated with VGI were hemostatic agents applied to the surgical field intraoperatively (P = .003) and perioperative hypoxemia (P = .027). Postoperative factors associated with VGI were discharge from the hospital to skilled nursing facility or acute rehabilitation facility (P = .005) and unscheduled clinic visits (P = .008). CONCLUSION: We measured a 15% incidence of VGI and identified multiple pre-, intra-, and postoperative associated factors. Vigilance is required to prevent VGI and knowledge of specific risk factors is important.
Subject(s)
Incidence , Transplants/abnormalities , Vascular Diseases/surgery , Adult , Aged , Aged, 80 and over , Female , Humans , Lower Extremity/blood supply , Male , Middle Aged , Retrospective Studies , Risk Factors , Surgical Wound Infection/epidemiology , Transplants/microbiology , Virginia/epidemiologyABSTRACT
Bacterial biofilms have been found in many, if not all, chronic wounds. Their excessive extracellular matrix secretion and the metabolic changes that they undergo render them highly tolerant of many antibiotic and antimicrobial treatments. Physical removal and/or disruption are a common approach to treating wounds suspected of having bacterial biofilms. While many of these techniques use mechanical energy as the primary means of removal, we have begun to investigate if surfactants could facilitate the removal of bacterial biofilms, or if they might sensitise the biofilms to antimicrobial interventions. We tested a new surfactant-based wound gel on an ex vivo porcine skin explant model infected with a functionally tolerant 3-day biofilm. The wounds were dressed with a surfactant-based gel directly on the wound or with moistened gauze. The wounds were then wiped daily with moistened gauze, and the gel or gauze was re-applied. Each day, an explant from each group was harvested and tested for total viable bacteria counts and viable biofilm-protected bacteria counts. The results show that daily wiping with moistened gauze led to an initial decrease of bacteria, but by day 3, the biofilm had been fully re-established to the same level prior to the beginning of treatment. For the surfactant-based treatment, there was no detectable functional biofilm after the first treatment. The gauze control, which was also subjected to daily wiping, still contained functional biofilms, indicating that this result was not due to wiping alone. The total bacteria in the surfactant-treated explants steadily decreased through day 3, when there were no detectable bacteria, while the wiping-only control bacteria counts remained steady. The use of a moist gauze to wipe the visually apparent slime off of a wound appears to be insufficient to reduce biofilm over a 3-day period. Daily application of the surfactant gel dressing and wiping reduced the biofilm to undetectable levels within 3 days in a skin explant model. A 3-day regimen of dressing the wound model with a surfactant gel followed by gentle removal of the gel by wiping with a moistened gauze appears to be a simple and adequate approach to removing a bacterial biofilm infection in an ex vivo model. Additional clinical evidence is needed to determine if this promising approach can perform the same in clinically infected chronic wounds.
Subject(s)
Anti-Infective Agents/therapeutic use , Bandages , Biofilms/drug effects , Pseudomonas Infections/drug therapy , Surface-Active Agents/therapeutic use , Transplants/microbiology , Wound Infection/drug therapy , Animals , Female , Humans , Male , Pseudomonas aeruginosa/drug effects , Swine , Wound HealingABSTRACT
Because of global mobility and migration resulting in a growing diversity of the donor pool, the risk for donor-derived tuberculosis in solid organ transplant recipients becomes more and more relevant, even in countries with a low overall tuberculosis incidence. Here, we describe a case series of donor-derived tuberculosis in 2 of 3 solid organ transplant recipients and one medical staff member in Germany resulting in the death of one recipient. This case series highlights the relevance of this topic to clinicians. It advocates for a better communication between organ procurement organizations and transplant centers regarding donor information and transplant recipient outcome. Furthermore, it underpins the necessity for a standardized critical incident reporting system in the german transplant system to improve short- and long-term recipient's safety, health and survival.
Subject(s)
Organ Transplantation/adverse effects , Tissue Donors , Transplant Recipients , Transplants/microbiology , Tuberculosis , Aged , Antitubercular Agents/administration & dosage , Antitubercular Agents/therapeutic use , Female , Health Personnel , Humans , Male , Middle Aged , Tuberculosis/drug therapy , Tuberculosis/microbiology , Tuberculosis/transmissionABSTRACT
Cytomegalovirus (CMV) primary infection or re-activation in solid organ transplant (SOT) recipients is associated with increased morbidity and mortality, with patients with IgG-CMV D+/R- sero-matching at greater risk. The impact of pre-transplant CMV-specific host cellular immunity on the long-term risk of CMV replication in kidney transplants (KT) was prospectively evaluated in eighty patients by CMV-EliSpot assay. The study population included 54 male and 26 female recipients, with CMV-IgG distribution: 60 D+/R+, 11 D-/R+, 7 D+/R-, 2 D-/R-. At pre-transplantation, 49 KT (61.3%) were CMV-responders by EliSpot. At 3-month follow up, 16 (32.7%) out of 49 CMV-responders showed CMV blood infection, compared to 8 (25.8%) out of 31 non-responders. No further episode of CMV viraemia was reported in the responder group, in comparison to 15 out 31 non-responders (48.4%) showing at least one episode of CMV-DNAemia at 12-month follow-up. Baseline CMV-IgG serology showed a strong correlation with EliSpot determinations; KT recipients exhibiting at least one episode of CMV viraemia at 12-month follow-up showed lower baseline CMV-EliSpot values than those without signs of CMV replication. The study suggests that monitoring CMV-specific T-cell responses at pre-transplantation by EliSpot assay may be useful for predicting the post-transplantation risk of CMV infection and reactivation.
Subject(s)
Cytomegalovirus Infections/immunology , Cytomegalovirus/immunology , Postoperative Complications/immunology , Transplants/microbiology , Adult , Aged , Antibodies, Viral/blood , Cytomegalovirus/genetics , Cytomegalovirus/physiology , Cytomegalovirus Infections/blood , Cytomegalovirus Infections/virology , Enzyme-Linked Immunospot Assay , Female , Humans , Kidney Transplantation , Male , Middle Aged , Postoperative Complications/blood , Postoperative Complications/virology , Prospective Studies , Transplant Recipients/statistics & numerical dataABSTRACT
Clostridium difficile-associated diarrhea is a problem most hospital-based physicians will face in their career. This review aims to refresh current knowledge with regard to Clostridium difficile infection and bring physicians up to date with the latest developments in the growing field of fecal microbiota transplantation, the benefits it offers, and the promise this and other developments hold for the future.
Subject(s)
Enterocolitis, Pseudomembranous , Feces/microbiology , Gastrointestinal Tract , Microbiota , Transplants/microbiology , Anti-Bacterial Agents/adverse effects , Clostridioides difficile/isolation & purification , Enterocolitis, Pseudomembranous/etiology , Enterocolitis, Pseudomembranous/microbiology , Enterocolitis, Pseudomembranous/therapy , Gastrointestinal Tract/microbiology , Gastrointestinal Tract/physiopathology , Humans , Microbiota/drug effects , Microbiota/physiology , Outcome Assessment, Health CareABSTRACT
Various compositions of synthetic calcium phosphates (CaP) have been proposed and their use has considerably increased over the past decades. Besides differences in physico-chemical properties, resorption and osseointegration, artificial CaP bone graft might differ in their resistance against biofilm formation. We investigated standardised cylinders of 5 different CaP bone grafts (cyclOS, chronOS (both ß-TCP (tricalcium phosphate)), dicalcium phosphate (DCP), calcium-deficient hydroxyapatite (CDHA) and α-TCP). Various physico-chemical characterisations e.g., geometrical density, porosity, and specific surface area were investigated. Biofilm formation was carried out in tryptic soy broth (TSB) and human serum (SE) using Staphylococcus aureus (ATCC 29213) and S. epidermidis RP62A (ATCC 35984). The amount of biofilm was analysed by an established protocol using sonication and microcalorimetry. Physico-chemical characterisation showed marked differences concerning macro- and micropore size, specific surface area and porosity accessible to bacteria between the 5 scaffolds. Biofilm formation was found on all scaffolds and was comparable for α-TCP, chronOS, CDHA and DCP at corresponding time points when the scaffolds were incubated with the same germ and/or growth media, but much lower for cyclOS. This is peculiar because cyclOS had an intermediate porosity, mean pore size, specific surface area, and porosity accessible to bacteria. Our results suggest that biofilm formation is not influenced by a single physico-chemical parameter alone but is a multi-step process influenced by several factors in parallel. Transfer from in vitro data to clinical situations is difficult; thus, advocating the use of cyclOS scaffolds over the four other CaP bone grafts in clinical situations with a high risk of infection cannot be clearly supported based on our data.
Subject(s)
Biofilms/drug effects , Calcium Phosphates/pharmacology , Staphylococcus aureus/drug effects , Staphylococcus epidermidis/drug effects , Transplants/microbiology , Bone Transplantation , Calcium Phosphates/chemistry , Porosity , Staphylococcus aureus/physiology , Staphylococcus epidermidis/physiology , Tissue Scaffolds/chemistry , Tissue Scaffolds/microbiology , Transplants/chemistryABSTRACT
INTRODUCTION: Solid organ transplant recipients have a higher frequency of tuberculosis (TB) than the general population, with mortality rates of approximately 30%. Although donor-derived TB is reported to account for <5% of TB in solid organ transplants, the source of Mycobacterium tuberculosis infection is infrequently determined. METHODS: We report 3 new cases of pulmonary TB in lung transplant recipients attributed to donor infection, and review the 12 previously reported cases to assess whether cases could have been prevented and whether any cases that might occur in the future could be detected and investigated more quickly. Specifically, we evaluate whether opportunities existed to determine TB risk on the basis of routine donor history, to expedite diagnosis through routine mycobacterial smears and cultures of respiratory specimens early post transplant, and to utilize molecular tools to investigate infection sources epidemiologically. FINDINGS: On review, donor TB risk was present among 7 cases. Routine smears and cultures diagnosed 4 asymptomatic cases. Genotyping was used to support epidemiologic findings in 6 cases. CONCLUSION: Validated screening protocols, including microbiological testing and newer technologies (e.g., interferon-gamma release assays) to identify unrecognized M. tuberculosis infection in deceased donors, are warranted.
Subject(s)
Lung Transplantation/adverse effects , Mycobacterium tuberculosis/isolation & purification , Transplants/microbiology , Tuberculosis, Pulmonary/etiology , Antitubercular Agents/therapeutic use , Early Diagnosis , Female , Humans , Interferon-gamma Release Tests , Male , Middle Aged , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/prevention & controlABSTRACT
BACKGROUND: Donor-derived infections from organ transplantation are rare occurrences with preoperative screening practices. Ehrlichia chaffeensis, a tick-borne illness, transmitted through solid organ transplantation has not been reported previously to our knowledge. We present cases of 2 renal allograft recipients who developed severe E. chaffeensis infection after receipt of organs from a common deceased donor. METHODS: The 2 renal transplant patients who developed E. chaffeensis infection are reported in case study format with review of the literature. RESULTS: Approximately 3 weeks after renal transplantation, both patients developed an acute febrile illness and rapid clinical decline. Recipient A underwent an extensive infectious workup that revealed positive E. chaffeensis DNA from polymerase chain reaction on peripheral blood. Recipient B's clinical team obtained acute and convalescent antibody titers for E. chaffeensis, which demonstrated acute infection. Recipients A and B were treated with doxycycline and tigecycline, respectively, with clinical cure. CONCLUSIONS: These cases demonstrate that tick-borne pathogens, such as E. chaffeensis, can be transmitted through renal transplantation. E. chaffeensis can be associated with excessive morbidity and mortality, commonly owing to delay in diagnosis and poor response to non-tetracycline antibiotics. In populations with endemic tick-borne illness, donors should be questioned about tick exposure, and appropriate antibiotics can be administered if indicated.
Subject(s)
Ehrlichia chaffeensis/isolation & purification , Ehrlichiosis/transmission , Kidney Failure, Chronic/surgery , Kidney Transplantation/adverse effects , Transplants/microbiology , Ehrlichiosis/etiology , Female , Humans , Male , Middle Aged , Severity of Illness IndexABSTRACT
According to the European Pharmacopoeia sterility testing of products includes an incubation time of 14 days in thioglycollate medium and soya-bean casein medium. In this case a large period of time is needed for product testing. So we designed a study to evaluate an alternative method for sterility testing. The aim of this study was to reduce the incubation time for the routinely produced products in our tissue bank (cornea and amnion grafts) by obtaining the same detection limit, accurateness and recovery rates as the reference method described in the European Pharmacopoeia. The study included two steps of validation. Primary validation compared the reference method with the alternative method. Therefore eight bacterial and two fungi test strains were tested at their preferred milieu. A geometric dilution series from 10 to 0.625 colony forming unit per 10 ml culture media was used. Subsequent to the evaluation the second part of the study started including the validation of the fertility of the culture media and the parallel testing of the two methods by investigating products. For this purpose two product batches were tested in three independent runs. Concerning the validation we could not find any aberration between the alternative and the reference method. In addition, the recovery rate of each microorganism was between 83.33 and 100 %. The alternative method showed non-inferiority regarding accuracy to the reference method. Due to this study we reduced the sterility testing for cornea and amniotic grafts to 9 days.
Subject(s)
Bacteria/isolation & purification , Cornea/microbiology , Fungi/isolation & purification , Tissue Banks , Transplants/microbiology , Culture Media , HumansSubject(s)
Bacteremia/drug therapy , Methicillin-Resistant Staphylococcus aureus/drug effects , Oxazolidinones/therapeutic use , Staphylococcal Infections/drug therapy , Tetrazoles/therapeutic use , Transplants/microbiology , Aged , Endovascular Procedures/adverse effects , Humans , Male , Recurrence , Time FactorsABSTRACT
A tissue-engineered construct (TEC) has previously been used for treating bone defects due to its strong osteogenic capability. However, transplantation of a TEC involves an open surgery that can cause infection. To overcome the potential risk of infection after TEC transplantation, we designed a system for the controlled release of antibiotics using fibrin gel-coated vancomycin alginate beads (FG-Vanco-AB) that can supply sustained antibiotics at the graft site. A TEC with FG-Vanco-AB was transplanted into critically sized bone defects of the right femur in a goat. As a control, the TEC without FG-Vanco-AB was transplanted into the left femur defect of the same goat. The breakpoint sensitivity of vancomycin for S. aureus (5 mg/L) was used as a known standard. Study results showed that the duration of time with vancomycin concentrations greater than 5 mg/L in the right graft site, blood, and left graft site were 28 days, 7 days, and 2 days, respectively. The bioactivity regarding vancomycin release was analysed by antibiotic disc diffusion. The vancomycin concentration was decreased from the centre of the graft to both ends of the femur. Radionuclide bone imaging showed no significant difference between the right and left TECs at either 28 or 56 days post-operation. Computed tomography and histological observation showed both sides' bone defects were healed by TEC at 112 days post-operation, and there was no significant difference in computed tomography value. These results suggest that FG-Vanco-AB in transplanted bone provided the ability to kill bacteria in local bone tissue while not interfering with the process of bone reconstruction and wound healing.