An Integrated Photonic Biosensing Platform for Pathogen Detection in Aquaculture.

Aquaculture is expected to play a vital role in solving the challenge of sustainably providing the growing world population with healthy and nutritious food. Pathogen outbreaks are a major risk for the sector, so early detection and a timely response are crucial. This can be enabled by monitoring the pathogen levels in aquaculture facilities. This paper describes a photonic biosensing platform based on silicon nitride waveguide technology with integrated active components, which could be used for such applications. Compared to the state of the art, the current system presents improvements in terms of miniaturization of the Photonic Integrated Circuit (PIC) and the development of wafer-level processes for hybrid integration of active components and for material-selective chemical and biological surface modification. Furthermore, scalable processes for integrating the PIC in a microfluidic cartridge were developed, as well as a prototype desktop readout instrument. Three bacterial aquaculture pathogens (Aeromonas salmonicida, Vagococcus salmoninarum, and Yersinia ruckeri) were selected for assay development. DNA biomarkers were identified, corresponding primer-probe sets designed, and qPCR assays developed. The biomarker for Aeromonas was also detected using the hybrid PIC platform. This is the first successful demonstration of biosensing on the hybrid PIC platform.

Mechanophenotyping of 3D multicellular clusters using displacement arrays of rendered tractions.

Epithelial tissues mechanically deform the surrounding extracellular matrix during embryonic development, wound repair, and tumor invasion. Ex vivo measurements of such multicellular tractions within three-dimensional (3D) biomaterials could elucidate collective dissemination during disease progression and enable preclinical testing of targeted antimigration therapies. However, past 3D traction measurements have been low throughput due to the challenges of imaging and analyzing information-rich 3D material deformations. Here, we demonstrate a method to profile multicellular clusters in a 96-well-plate format based on spatially heterogeneous contractile, protrusive, and circumferential tractions. As a case study, we profile multicellular clusters across varying states of the epithelial-mesenchymal transition, revealing a successive loss of protrusive and circumferential tractions, as well as the formation of localized contractile tractions with elongated cluster morphologies. These cluster phenotypes were biochemically perturbed by using drugs, biasing toward traction signatures of different epithelial or mesenchymal states. This higher-throughput analysis is promising to systematically interrogate and perturb aberrant mechanobiology, which could be utilized with human-patient samples to guide personalized therapies.

Musculoskeletal tuberculosis revisited: bone and joint tuberculosis in Austria.

BACKGROUND: To prevent further spread of the disease and secondary deformity, musculoskeletal tuberculosis (TB) remains a challenge in terms of early diagnosis and treatment. This study gives an overview on TB trends in Austria (pulmonary and extrapulmonary TB) (A) and analyses a retrospective series of musculoskeletal TB cases diagnosed and treated at an Austrian tertiary centre (B). METHODS: (A) We analysed data obtained from the Austrian national TB registry to provide information on TB patients´ demographics and manifestation sites between 1995 and 2019. (B) Furthermore, we performed an observational study of all patients with a confirmed diagnosis of musculoskeletal TB who were admitted to the Department of Orthopaedics and Trauma, Medical University of Graz (2005-2019). Demographic, diagnostic, clinical and follow-up data were retrieved from the medical records. RESULTS: (A) From 1995 to 2019, a significant linear reduction in overall Austrian tuberculosis incidence rates occurred (p < 0.001). In the period investigated, Austria recorded a total of 307 patients with musculoskeletal TB. (B) Our retrospective case-series included 17 individuals (9 males, 8 females; average follow-up 48.4 months; range 0-116). There was a biphasic age distribution with a peak in elderly native Austrians (median 69, range 63-92), and a second peak in younger patients with a migration background (median 29, range 18-39). Sites of manifestation were the spine (n = 10), peripheral joints (n = 5), and the soft tissues (n = 2). Diagnosis was based on histology (n = 13), PCR (n = 14), and culture (n = 12). Eleven patients underwent surgery (64.7%). Secondary deformities were frequent (n = 9), and more often observed in patients with spinal TB (n = 6). CONCLUSION: Musculoskeletal TB should be considered if untypical joint infections or nonspecific bone lesions occur in younger patients with a migration background or in patients with specific risk factors.

Implementation of rapid antimicrobial susceptibility testing combined with routine infectious disease bedside consultation in clinical practice (RAST-ID): a prospective single-centre study.

OBJECTIVES: Recently, EUCAST released guidelines for rapid antimicrobial susceptibility testing (RAST) directly from positive blood culture bottles. The aim of our prospective single-centre clinical study was to assess the proportion of readable results and errors compared with routine antimicrobial susceptibility testing and the clinical consequences drawn by infectious disease (ID) physicians from RAST results during same-day bedside consultation. METHODS: All positive blood cultures suitable for RAST from January to December 2019 were included and RAST results at 4 and 6 h compared with standard disc diffusion. The real-life impact of RAST on clinical decisions was assessed during same-day ID bedside consultation. RESULTS: The proportion of readable RAST results was significantly higher after 6 h of incubation compared with after 4 h (881/930 versus 642/847; P < 0.0001). Major and very major errors were rare (17/642 after 4 h and 12/881 after 6 h; P = 0.087). ID consultation was performed in 134 patients after the RAST result. Antimicrobial treatment was changed in 73 patients and 84 additional measures (i.e. imaging studies, surgery, additional resistance testing) were ordered in 62 patients. CONCLUSIONS: RAST according to EUCAST methods was easy to implement with a low number of major and very major errors after 6 h of incubation. ID physicians performing bedside consultations frequently used this information to change antimicrobial treatment and recommended additional measures.

Antifungal prophylaxis for prevention of COVID-19-associated pulmonary aspergillosis in critically ill patients: an observational study.

BACKGROUND: Coronavirus disease 19 (COVID-19)-associated pulmonary aspergillosis (CAPA) emerged as important fungal complications in patients with COVID-19-associated severe acute respiratory failure (ARF). Whether mould active antifungal prophylaxis (MAFP) can prevent CAPA remains elusive so far. METHODS: In this observational study, we included all consecutive patients admitted to intensive care units with COVID-19-associated ARF between September 1, 2020, and May 1, 2021. We compared patients with versus without antifungal prophylaxis with respect to CAPA incidence (primary outcome) and mortality (secondary outcome). Propensity score adjustment was performed to account for any imbalances in baseline characteristics. CAPA cases were classified according to European Confederation of Medical Mycology (ECMM)/International Society of Human and Animal Mycoses (ISHAM) consensus criteria. RESULTS: We included 132 patients, of whom 75 (57%) received antifungal prophylaxis (98% posaconazole). Ten CAPA cases were diagnosed, after a median of 6 days following ICU admission. Of those, 9 CAPA cases were recorded in the non-prophylaxis group and one in the prophylaxis group, respectively. However, no difference in 30-day ICU mortality could be observed. Thirty-day CAPA incidence estimates were 1.4% (95% CI 0.2-9.7) in the MAFP group and 17.5% (95% CI 9.6-31.4) in the group without MAFP (p = 0.002). The respective subdistributional hazard ratio (sHR) for CAPA incidence comparing the MAFP versus no MAFP group was of 0.08 (95% CI 0.01-0.63; p = 0.017). CONCLUSION: In ICU patients with COVID-19 ARF, antifungal prophylaxis was associated with significantly reduced CAPA incidence, but this did not translate into improved survival. Randomized controlled trials are warranted to evaluate the efficacy and safety of MAFP with respect to CAPA incidence and clinical outcomes.

Cat at home? Cat scratch disease with atypical presentations and aggressive radiological findings mimicking sarcoma, a potential diagnostic pitfall.

Background and purpose - Cat scratch disease (CSD) is a self-limiting disease caused by Bartonella (B.) henselae. It is characterized by granulomatous infection, most frequently involving lymph nodes. However, it can present with atypical symptoms including musculoskeletal manifestations, posing a diagnostic challenge. We describe the prevalence and demographics of CSD cases referred to a sarcoma center, and describe the radiological, histological, and molecular findings.Patients and methods - Our cohort comprised 10 patients, median age 27 years (12-74) with clinical and radiological findings suspicious of sarcoma.Results - 7 cases involved the upper extremities, and 1 case each involved the axilla, groin, and knee. B. henselae was found in 6 cases tested using polymerase chain reaction and serology in 5 cases. 9 cases were soft tissue lesions and 1 lesion involved the bone. 1 patient had concomitant CSD with melanoma metastasis in enlarged axillary lymph nodes. On MRI, 5 soft tissue lesions were categorized as probably inflammatory. In 3 cases, with still detectable lymph node structure and absent or initial liquefaction, the differential diagnosis included lymph node metastasis. A sarcoma diagnosis was suggested in 4 cases. The MRI imaging features of the bone lesion were suspicious of a bone tumor or osteomyelitis.Interpretation - Atypical imaging findings cause a diagnostic challenge and the differential diagnosis includes malignant neoplasms (such as sarcoma or carcinoma metastasis) and other infections. The distinction between these possibilities is crucial for treatment and prognosis.

T2Candida magnetic resonance in patients with invasive candidiasis: Strengths and limitations.

T2Candida enables detection of five Candida species in whole blood within approximately 5 hours. Routinely drawn EDTA blood samples were prospectively stored and tested with T2Candida in patients with invasive candidiasis identified by routine index blood or sterile site cultures. T2Candida was compared to diagnostic blood and sterile site cultures and also performed with samples obtained prior and after collection of index cultures. T2Candida was evaluated with 133 samples of 32 patients with candidemia and 22 patients with deep-seated invasive candidiasis. In the candidemic group 28/32 (87.5%) patients had at least one positive T2Candida result at any time point. A total of 17/25 (68%) candidemic patients had a positive T2Candida sample that was drawn concurrently to the index blood culture. In the per patient analysis 17/18 (94.4%) candidemic patients with matched T2Candida samples and peripheral blood cultures at any timepoint had a positive T2Candida test. T2Candida revealed discordant Candida species identification in two candidemic patients. Six of 22 (27.3%) deep-seated IC patients had a positive T2Candida result. Despite advanced time-to-results the clinical value of T2Candida in diagnosing candidemia seems to be limited by missing blood culture positive cases. Positivity rates of T2Candida increased when serial T2Candida samples were tested. In patients with suspected deep-seated invasive candidiasis T2Candida might act as a blood based adjunct to sterile site cultures.

Antifungal Prophylaxis with Posaconazole Delayed-Release Tablet and Oral Suspension in a Real-Life Setting: Plasma Levels, Efficacy, and Tolerability.

We continuously determined posaconazole plasma concentrations (PPCs) in 61 patients with hematological malignancies receiving posaconazole (PCZ) delayed-release tablets (DRT; 48 patients; median duration of intake, 92 days) and PCZ oral solution (OS; 13 patients; median duration of intake, 124 days). PCZ DRT and OS antifungal prophylaxis was efficient and well tolerated. Thirty-four of 48 patients (71%) receiving DRT always had PPCs of >0.7 mg/liter, while 14 of 48 patients (29%) had at least one PPC of ≤0.7 mg/liter. In patients receiving OS, 4 of 13 patients (31%) always had PPCs of >0.7 mg/liter, 6 of 13 patients (46%) had at least one PPC of ≤0.7 mg/liter, and 3 (23%) patients never reached a PPC of 0.7 mg/liter. In patients with at least one determined PPC, the mean proportion of all PPCs of >0.7 mg/liter was 91% for PCZ DRT, whereas it was 52% for PCZ OS (P = 0.001). In the per sample analysis, PPCs were significantly more likely to be >0.7 mg/liter in patients receiving DRT than in patients receiving OS (PPCs were >0.7 mg/liter in 91.4% [297/325] of patients receiving DRT versus 70.3% [85/121] of patients receiving OS; P < 0.001). Patients receiving PCZ DRT had higher proportions of PPCs of >0.7 mg/liter than patients receiving OS both in the per patient and in the per sample analyses. Two patients (3%) had side effects during PCZ prophylaxis, and one (2%) had fungal breakthrough infection. Therapeutic drug monitoring enables detection of extended periods of PPCs of ≤0.7 mg/liter (e.g., due to nonadherence or graft-versus-host disease), which may also be associated with the loss of protective intracellular PCZ concentrations, regardless of the PCZ formulation.

Invasive aspergillosis in patients with underlying liver cirrhosis: a prospective cohort study.

The aim of this study was to determine the prevalence of invasive aspergillosis (IA) in patients with liver cirrhosis and the performance of serum galactomannan (GM) screening. Patients with decompensated liver cirrhosis and patients with compensated liver cirrhosis presenting with fever and/or respiratory symptoms were prospectively enrolled. All patients were screened by serum GM twice weekly irrespective of clinical signs and symptoms. Positive serum GM triggered work-up consisting of chest computed tomography and in case of pathological findings bronchoscopy. 150 patients were included in the study. Two (1.3%) had probable, one (0.7%) had possible, and 147 (98%) had no evidence of IA. Both patients with probable IA had compensated liver cirrhosis. Sensitivity for serum GM screening for probable versus no IA was 0.5 (95% CI, 0.09-0.91), specificity 0.97 (95% CI: 0.92-0.99), negative predictive value 0.99 (95% CI, 0.96-0.99) and positive predictive value (PPV) 0.17 (95% CI, 0.01-0.64). PPV was 0.5 (95% CI, 0.03-0.98) in patients with clinical suspicion of IA. In conclusion, prevalence of IA in patients with liver cirrhosis seems to be low. Targeted GM testing in case of clinical suspicion of IA may be associated with markedly higher PPVs when compared to universal GM screening in patients with liver cirrhosis.

Bioengineered functional brain-like cortical tissue.

The brain remains one of the most important but least understood tissues in our body, in part because of its complexity as well as the limitations associated with in vivo studies. Although simpler tissues have yielded to the emerging tools for in vitro 3D tissue cultures, functional brain-like tissues have not. We report the construction of complex functional 3D brain-like cortical tissue, maintained for months in vitro, formed from primary cortical neurons in modular 3D compartmentalized architectures with electrophysiological function. We show that, on injury, this brain-like tissue responds in vitro with biochemical and electrophysiological outcomes that mimic observations in vivo. This modular 3D brain-like tissue is capable of real-time nondestructive assessments, offering previously unidentified directions for studies of brain homeostasis and injury.

Chemical Dissolution Pathways of MoS2 Nanosheets in Biological and Environmental Media.

Material stability and dissolution in aqueous media are key issues to address in the development of a new nanomaterial intended for technological application. Dissolution phenomena affect biological and environmental persistence; fate, transport, and biokinetics; device and product stability; and toxicity pathways and mechanisms. This article shows that MoS2 nanosheets are thermodynamically and kinetically unstable to O2-oxidation under ambient conditions in a variety of aqueous media. The oxidation is accompanied by nanosheet degradation and release of soluble molybdenum and sulfur species, and generates protons that can colloidally destabilize the remaining sheets. The oxidation kinetics are pH-dependent, and a kinetic law is developed for use in biokinetic and environmental fate modeling. MoS2 nanosheets fabricated by chemical exfoliation with n-butyl-lithium are a mixture of 1T (primary) and 2H (secondary) phases and oxidize rapidly with a typical half-life of 1-30 days. Ultrasonically exfoliated sheets are in pure 2H phase, and oxidize much more slowly. Cytotoxicity experiments on MoS2 nanosheets and molybdate ion controls reveal the relative roles of the nanosheet and soluble fractions in the biological response. These results indicate that MoS2 nanosheets will not show long-term persistence in living systems and oxic natural waters, with important implications for biomedical applications and environmental risk.

Elevated levels of interleukin 17A and kynurenine in candidemic patients, compared with levels in noncandidemic patients in the intensive care unit and those in healthy controls.

BACKGROUND: The interplay between Candida species and pattern recognition receptors, interleukins, kynurenine, and T cells has been studied in murine and ex vivo human studies, but data are lacking from patients with invasive fungal infections. Interleukin 17A (IL-17A) is considered an important component in host defense against Candida infections and is modulated by Candida-induced impairment of tryptophan-kynurenine metabolism. METHODS: Dectin-1, Toll-like receptor 2, and Toll-like receptor 4 expression; regulatory T cell (Treg) percentages; and interleukin 6, interleukin 10, IL-17A, interleukin 22, interleukin 23, interferon γ, kynurenine, and tryptophan levels were determined in candidemic patients and compared to levels in noncandidemic patients who are in the intensive care unit (ICU) and receiving antibiotic therapy and those in healthy controls, both with and without Candida colonization. RESULTS: Candidemic patients had significantly higher IL-17A and kynurenine levels, compared with noncandidemic patients, including Candida-colonized ICU patients and healthy controls. Within candidemic patients, time-dependent elevation of IL-17A and kynurenine levels was detected. IL-17A areas under the curve for differentiation between patients with early candidemia and those without candidemia (ICU patients, including Candida-colonized patients, and healthy controls) were between 0.94 (95% confidence interval [CI], .89-.99) and 0.99 (95% CI, .99-1). CONCLUSIONS: Candidemic patients had significantly higher IL-17A and kynurenine levels, compared with noncandidemic patients. The statistically significant association between IL-17A and kynurenine levels and candidemia suggests their potential as biomarkers for anticipation of invasive candidiasis. CLINICAL TRIALS REGISTRATION: NCT00786903.

Contaminated handwashing sinks as the source of a clonal outbreak of KPC-2-producing Klebsiella oxytoca on a hematology ward.

We investigated sinks as possible sources of a prolonged Klebsiella pneumonia carbapenemase (KPC)-producing Klebsiella oxytoca outbreak. Seven carbapenem-resistant K. oxytoca isolates were identified in sink drains in 4 patient rooms and in the medication room. Investigations for resistance genes and genetic relatedness of patient and environmental isolates revealed that all the isolates harbored the blaKPC-2 and blaTEM-1 genes and were genetically indistinguishable. We describe here a clonal outbreak caused by KPC-2-producing K. oxytoca, and handwashing sinks were a possible reservoir.

Detection of central venous catheter-related bloodstream infections in haematooncological patients.

BACKGROUND: Catheter-related bloodstream infections (CRBSIs) are currently detected in patients with clinically suspicion. The aim of our study was to evaluate whether CRBSIs could be anticipated and detected in a subclinical stage by peptide nucleic acid fluorescence in situ hybridization (PNA FISH) using universal hybridization probes or acridine orange leucocyte cytospin (AOLC) tests in haematooncological patients with central venous catheters (CVCs) in situ. MATERIALS AND METHODS: Peptide nucleic acid fluorescence in situ hybridization and AOLC tests using blood samples from one CVC lumen/port chamber in haematooncological patients were continuously performed. These results were compared to those obtained from routinely performed CRBSI diagnostic tests. RESULTS: One hundred and eighty-two patients with 342 catheter periods were investigated. Seventeen CRBSI cases were detected in 6466 CVC days by routine measures resulting in a CRBSI rate of 2.6/1000 catheter days. Two of 17 showed positive PNA FISH tests, and five positive AOLC test results before the diagnosis were established with routine measures. The screening revealed further seven patients with positive universal PNA FISH tests and 10 positive AOLC tests without symptoms indicative for infection and were therefore considered not to have CRBSI. CONCLUSIONS: Sampling of only one CVC lumen/port chamber screening for CRBSI in haematooncological patients seems not to be a useful tool for anticipative diagnosis of CRBSI. Reasons for false-negative results might include origin of CRBSIs from the other CVC lumina not sampled for screening, and false-positive results might origin from catheter colonization without subsequent spread of micro-organisms into the peripheral bloodstream.

Stabilization of vaccines and antibiotics in silk and eliminating the cold chain.

Sensitive biological compounds, such as vaccines and antibiotics, traditionally require a time-dependent "cold chain" to maximize therapeutic activity. This flawed process results in billions of dollars worth of viable drug loss during shipping and storage, and severely limits distribution to developing nations with limited infrastructure. To address these major limitations, we demonstrate self-standing silk protein biomaterial matrices capable of stabilizing labile vaccines and antibiotics, even at temperatures up to 60 °C over more than 6 months. Initial insight into the mechanistic basis for these findings is provided. Importantly, these findings suggest a transformative approach to the cold chain to revolutionize the way many labile therapeutic drugs are stored and utilized throughout the world.

Loss of antimicrobial effect of trisodium citrate due to 'lock' spillage from haemodialysis catheters.

BACKGROUND: Due to its reported antimicrobial effects, hypertonic citrate (46.7%) is a widely used catheter lock solution, but following instillation, citrate inevitably spills into the systemic circulation. This process is mainly driven by hydraulic effects during instillation and density differences between blood and lock solution. Hence, in haemodialysis catheters, intra-luminal citrate concentration ranges from 0% (at the tip in catheters with side holes), 3% (between the side holes and the highest point of the catheter) to 46.7% (at the Luer end) with possible differences in antimicrobial effects. We investigated in vitro the antimicrobial effect of pure citrate 46.7%, citrate 46.7% diluted with saline and blood to a net concentration of 3% (=citrate 3%), and of citrate-free blood, simulating in vivo conditions in different catheter sections. METHODS: Time-kill studies measuring the antimicrobial effect of citrate 46.7%, citrate 3% and citrate-free blood were performed with overnight cultures of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). RESULTS: Citrate 46.7% reduced the number of E. coli by 2 log units but after 24 h, 10(6) CFU/mL were still present. Citrate 3% and citrate-free blood had no antimicrobial effect on E. coli. Citrate 46.7%, citrate 3% and citrate-free blood had scarce antimicrobial effect on S. aureus within 24 h. CONCLUSIONS: Spillage of catheter lock solution leading to reduced intra-luminal citrate concentrations considerably reduces the antimicrobial effect of citrate 46.7% on E. coli. As none of the solutions tested had relevant antimicrobial effect on S. aureus, the antimicrobial effect of 46.7% citrate lock solution in vivo has to be seriously questioned.

Vitamin D status and its association with season, hospital and sepsis mortality in critical illness.

INTRODUCTION: Vitamin D plays a key role in immune function. Deficiency may aggravate the incidence and outcome of infectious complications in critically ill patients. We aimed to evaluate the prevalence of vitamin D deficiency and the correlation between serum 25-hydroxyvitamin D (25(OH) D) and hospital mortality, sepsis mortality and blood culture positivity. METHODS: In a single-center retrospective observational study at a tertiary care center in Graz, Austria, 655 surgical and nonsurgical critically ill patients with available 25(OH) D levels hospitalized between September 2008 and May 2010 were included. Cox regression analysis adjusted for age, gender, severity of illness, renal function and inflammatory status was performed. Vitamin D levels were categorized by month-specific tertiles (high, intermediate, low) to reflect seasonal variation of serum 25(OH) D levels. RESULTS: Overall, the majority of patients were vitamin D deficient (<20 ng/ml; 60.2%) or insufficient (≥20 and <30 ng/dl; 26.3%), with normal 25(OH) D levels (>30 ng/ml) present in only 13.6%. The prevalence of vitamin D deficiency and mean 25(OH) D levels was significantly different in winter compared to summer months (P <0.001). Hospital mortality was 20.6% (135 of 655 patients). Adjusted hospital mortality was significantly higher in patients in the low (hazard ratio (HR) 2.05, 95% confidence interval (CI) 1.31 to 3.22) and intermediate (HR 1.92, 95% CI 1.21 to 3.06) compared to the high tertile. Sepsis was identified as cause of death in 20 of 135 deceased patients (14.8%). There was no significant association between 25(OH) D and C-reactive protein (CRP), leukocyte count or procalcitonin levels. In a subgroup analysis (n = 244), blood culture positivity rates did not differ between tertiles (23.1% versus 28.2% versus 17.1%, P = 0.361). CONCLUSIONS: Low 25(OH) D status is significantly associated with mortality in the critically ill. Intervention studies are needed to investigate the effect of vitamin D substitution on mortality and sepsis rates in this population.

Serum 1,3-beta-d-glucan for antifungal treatment stratification at the intensive care unit and the influence of surgery.

The purpose of this study was to evaluate a preemptive approach with serum 1,3-beta-d-glucan (BDG) as a marker for treatment stratification of systemic antifungal (AF) therapy in patients with clinical suspected invasive fungal infections (IFI) at intensive care units (ICU), and the impact of surgical procedures. A total of 66 ICU patients with clinical suspected IFI were included in this retrospective analysis. Serum BDG testing was performed prior to initiation of AF treatment and in addition to routine diagnostic measures. Based on the BDG results the initial clinical decision whether or not to start systemic AF therapy was re-evaluated. Impact of surgical procedures on clinical utility of serum BDG was evaluated in a sub-group of 25 patients who had undergone surgical procedures prior to BDG evaluation. BDG test results led to discontinuation of AF therapy in 13 patients, and initiation of AF therapy in seven patients. In 46 patients the clinical decision was confirmed by BDG. The majority of suspected, probable and proven IFI cases (10/13, 77%) was predicted by the test. BDG testing turned out positive in 9/25 (36%) of patients that had undergone recent surgery and levels correlated with clinical findings. Serum BDG evaluation seems to be a promising tool to guide AF therapy in ICU patients even after recent surgical procedures.

Potential factors for inadequate voriconazole plasma concentrations in intensive care unit patients and patients with hematological malignancies.

Voriconazole plasma concentrations (VPCs) vary widely, and concentrations outside the therapeutic range are associated with either worse outcome in invasive aspergillosis (IA) or increased toxicity. The primary goal of this cohort study conducted in a real-life setting was to identify potential factors associated with inadequate VPCs in ICU patients and patients with hematological malignancies. Within a period of 12 months, trough VPCs were obtained and analyzed with high-performance liquid chromatography, and the adequate range was defined as 1.5 to 5.5 mg/liter. VPCs of <1.5 mg/liter were defined as low, whereas VPCs of >5.5 mg/liter were defined as potentially toxic. A total of 221 trough VPCs were obtained in 61 patients receiving voriconazole, and 124/221 VPCs (56%) were found to be low. Multivariate analysis revealed that low VPCs were significantly associated with clinical failure of voriconazole, prophylactic use, younger age, underlying hematological malignancy, concomitant proton pump inhibitor (PPI) (pantoprazole was used in 88% of the patients), and absence of side effects. Low VPCs remained an independent predictor of clinical failure of voriconazole. The defined adequate range was reached in 79/221 (36%) VPCs. In 18 samples (8%), potentially toxic levels were measured. Multivariate analysis revealed higher body mass index (BMI), absence of hematological malignancy, therapeutic application, and diarrhea as factors associated with potentially toxic VPCs. Neurotoxic adverse events occurred in six patients and were mostly associated with VPCs in the upper quartile of our defined adequate range. In conclusion, potential factors like younger age, prophylaxis, underlying hematological malignancy, BMI, and concomitant PPI should be considered within the algorithm of voriconazole treatment.

Antibiotic-Releasing Silk Biomaterials for Infection Prevention and Treatment.

Effective treatment of infections in avascular and necrotic tissues can be challenging due to limited penetration into the target tissue and systemic toxicities. Controlled release polymer implants have the potential to achieve the high local concentrations needed while also minimizing systemic exposure. Silk biomaterials possess unique characteristics for antibiotic delivery including biocompatibility, tunable biodegradation, stabilizing effects, water-based processing and diverse material formats. We report on functional release of antibiotics spanning a range of chemical properties from different material formats of silk (films, microspheres, hydrogels, coatings). The release of penicillin and ampicillin from bulk-loaded silk films, drug-loaded silk microspheres suspended in silk hydrogels and bulk-loaded silk hydrogels was investigated and in vivo efficacy of ampicillin-releasing silk hydrogels was demonstrated in a murine infected wound model. Silk sponges with nanofilm coatings were loaded with gentamicin and cefazolin and release was sustained for 5 and 3 days, respectively. The capability of silk antibiotic carriers to sequester, stabilize and then release bioactive antibiotics represents a major advantage over implants and pumps based on liquid drug reservoirs where instability at room or body temperature is limiting. The present studies demonstrate that silk biomaterials represent a novel, customizable antibiotic platform for focal delivery of antibiotics using a range of material formats (injectable to implantable).