Long-term Risk of Serious Infections and Mortality Among Patients Surviving Drug Use-Associated Infective Endocarditis.

Among a statewide cohort of 1874 patients surviving hospitalization for drug use-associated endocarditis during 2017-2020, the 3-year risk of death or future hospitalization was 38% (16% for death before later infection, 14% for recurrent endocarditis, 14% for soft tissue, 9% for bacteremia, 5% for bone/joint, and 4% for spinal infections).

Quantifying the Time to Administer Outpatient Parenteral Antimicrobial Therapy: A Missed Opportunity to Compensate for the Value of Infectious Diseases.

Outpatient parenteral antimicrobial therapy (OPAT) relies on substantial uncompensated provider time. In this study of a large academic OPAT program, the median amount of unbilled OPAT management time was 27 minutes per week, per OPAT course. These data should inform benchmarks in pursuing novel payment approaches for OPAT.

Medications for Opioid Use Disorder and Mortality and Hospitalization Among People With Opioid Use-related Infections.

BACKGROUND: Severe skin and soft tissue infections related to injection drug use have increased in concordance with a shift to heroin and illicitly manufactured fentanyl. Opioid agonist therapy medications (methadone and buprenorphine) may improve long-term outcomes by reducing injection drug use. We aimed to examine the association of medication use with mortality among people with opioid use-related skin or soft tissue infections. METHODS: An observational cohort study of Medicaid enrollees aged 18 years or older following their first documented medical encounters for opioid use-related skin or soft tissue infections during 2007-2018 in North Carolina. The exposure was documented medication use (methadone or buprenorphine claim) in the first 30 days following initial infection compared with no medication claim. Using Kaplan-Meier estimators, we examined the difference in 3-year incidence of mortality by medication use, weighted for year, age, comorbidities, and length of hospital stay. RESULTS: In this sample, there were 13,286 people with opioid use-related skin or soft tissue infections. The median age was 37 years, 68% were women, and 78% were white. In Kaplan-Meier curves for the total study population, 12 of every 100 patients died during the first 3 years. In weighted models, for every 100 people who used medications, there were four fewer deaths over 3 years (95% confidence interval = 2, 6). CONCLUSION: In this study, people with opioid use-related skin and soft tissue infections had a high risk of mortality following their initial healthcare visit for infections. Methadone or buprenorphine use was associated with reductions in mortality.

Serratia endocarditis: antimicrobial management strategies and clinical outcomes.

OBJECTIVES: The incidence of Serratia endocarditis is increasing, yet optimal treatment has not been defined. Our objective was to investigate the outcomes of patients with Serratia endocarditis by treatment strategy. METHODS: We reviewed adult patients with definitive Serratia endocarditis at two independent health systems between July 2001 and April 2023. Combination therapy was defined as receipt of ≥2 in vitro active agents for ≥72 h. RESULTS: Seventy-five patients were included; 64% (48/75) were male and 85% (64/75) were people who inject drugs. Compared with monotherapy, receipt of combination therapy was associated with lower rates of microbiological failure (0% versus 15%, P = 0.026) and 90 day all-cause mortality (11% versus 31%, P = 0.049). Antimicrobial discontinuation due to an adverse event was more common among patients receiving combination therapy compared with monotherapy (36% versus 8%, P = 0.058). CONCLUSIONS: In the largest series of Serratia endocarditis to date, combination antibiotic treatment was associated with improved outcomes. However, larger, prospective studies are warranted.

The Impact of Discharge Against Medical Advice on Readmission After Opioid Use Disorder-Associated Infective Endocarditis: a National Cohort Study.

BACKGROUND: Hospitalizations for infective endocarditis (IE) associated with opioid use disorder (O-IE) have increased in the USA and have been linked to high rates of discharge against medical advice (DAMA). DAMA represents a truncation of care for a severe infection, yet patient outcomes after DAMA are unknown. OBJECTIVE: This study aimed to assess readmissions following O-IE and quantify the impact of DAMA on outcomes. DESIGN: A retrospective study of a nationally representative dataset of persons' inpatient discharges in the USA in 2016 PARTICIPANTS: A total of 6018 weighted persons were discharged for O-IE, stratified by DAMA vs. other discharge statuses. Of these, 1331 (22%) were DAMA. MAIN MEASURES: The primary outcome of interest was 30-day readmission rates, stratified by discharge type. We also examined the total number of hospitalizations during the year and estimated the effect of DAMA on readmission. KEY RESULTS: Compared with non-DAMA, those experiencing DAMA were more commonly female, resided in metropolitan areas, lower income, and uninsured. Crude 30-day readmission following DAMA was 50%, compared with 21% for other discharge types. DAMA was strongly associated with readmission in an adjusted logistic regression model (OR 3.72, CI 3.02-4.60). Persons experiencing DAMA more commonly had ≥2 more hospitalizations during the period (31% vs. 18%, p<0.01), and were less frequently readmitted at the same hospital (49% vs 64%, p<0.01). CONCLUSIONS: DAMA occurs in nearly a quarter of patients hospitalized for O-IE and is strongly associated with short-term readmission. Interventions to address the root causes of premature discharges will enhance O-IE care, reduce hospitalizations and improve outcomes.

Inpatient Hepatitis C Treatment Coordination and Initiation for Patients Who Inject Drugs.

BACKGROUND: With hepatitis C (HCV) incidence rising due to injection drug use, people who inject drugs (PWID) are a priority population for direct-acting antivirals (DAA). However, significant barriers exist. At our institution, hospitalized PWID were screened for HCV but not effectively linked to care. AIM: To improve retention in HCV care among hospitalized PWID. SETTING: Quaternary academic center in the Southeast US from August 2021 through August 2022. PARTICIPANTS: Hospitalized PWID with HCV. PROGRAM DESCRIPTION: E-consultation-prompted care coordination and HCV treatment with outpatient telehealth. PROGRAM EVALUATION: Care cascades were constructed to assess retention and HCV treatment, with the primary outcome defined as DAA completion or sustained virologic response after week 4. Of 28 patients, 11 started DAAs inpatient, 8 initiated outpatient, and 9 were lost to follow-up or transferred care. Overall, 82% were linked to care and 52% completed treatment. For inpatient initiators, 73% achieved the outcome. Of non-inpatient initiators, 71% were linked to care, 53% started treatment, and 36% achieved the outcome. DISCUSSION: Inpatient HCV treatment coordination, including DAA initiation, and telehealth follow-up, was feasible and highly effective for hospitalized PWID. Future steps should address barriers to inpatient DAA treatment and expand this model to other similar patient populations.

Normal aging in mice is associated with a global reduction in cortical spectral power and network-specific declines in functional connectivity.

Normal aging is associated with a variety of neurologic changes including declines in cognition, memory, and motor activity. These declines correlate with neuronal changes in synaptic structure and function. Degradation of brain network activity and connectivity represents a likely mediator of age-related functional deterioration resulting from these neuronal changes. Human studies have demonstrated both general decreases in spontaneous cortical activity and disruption of cortical networks with aging. Current techniques used to study cerebral network activity are hampered either by limited spatial resolution (e.g. electroencephalography, EEG) or limited temporal resolution (e.g., functional magnetic resonance imaging, fMRI). Here we utilize mesoscale imaging of neuronal activity in Thy1-GCaMP6f mice to characterize neuronal network changes in aging with high spatial resolution across a wide frequency range. We show that while evoked activity is unchanged with aging, spontaneous neuronal activity decreases across a wide frequency range (0.01-4 Hz) involving all regions of the cortex. In contrast to this global reduction in cortical power, we found that aging is associated with functional connectivity (FC) deterioration of select networks including somatomotor, cingulate, and retrosplenial nodes. These changes are corroborated by reductions in homotopic FC and node degree within somatomotor and visual cortices. Finally, we found that whole-cortex delta power and delta band node degree correlate with exploratory activity in young but not aged animals. Together these data suggest that aging is associated with global declines in spontaneous cortical activity and focal deterioration of network connectivity, and that these reductions may be associated with age-related behavioral declines.

Opioid misuse among persons with HIV engaged in care in the Southeastern US.

The prevalence of opioid misuse by people living with HIV (PLWH) during the current US opioid epidemic has not been fully described. Among a cohort of persons engaged in HIV care in North Carolina, we examined the prevalence of and risk factors for opioid misuse, defined as self-reported "street" opioid use (e.g., heroin) or nonmedical prescription opioid use on a patient reported outcomes survey. Recent (past three-month) opioid misuse among 1,440 PLWH in care 2012-2017 was 2% (95% CI 2-3%) and lifetime misuse 15% (13-16%). Persons reporting lifetime or recent misuse more commonly had hepatitis C and reported injecting drugs. In multivariable logistic regression models, male-to-male sexual contact was inversely associated with recent or lifetime misuse. White/non-Hispanic race/ethnicity was associated with lifetime misuse and CD4 count and viral load were not associated with opioid misuse. Among 32 persons reporting recent misuse, 81% had a contemporaneous viral load <50 copies/mL. In this cohort of PLWH engaged in care, recent opioid misuse prevalence was similar to general population estimates. Assessments of opioid misuse among PLWH not in care are urgently needed to fully characterize the impact of opioids on all PLWH.

Tuning the interfacial stoichiometry of InP core and InP/ZnSe core/shell quantum dots.

We demonstrate fine-tuning of the atomic composition of InP/ZnSe quantum dots (QDs) at the core/shell interface. Specifically, we control the stoichiometry of both anions (P, As, S, and Se) and cations (In and Zn) at the InP/ZnSe core/shell interface and correlate these changes with the resultant steady-state and time-resolved optical properties of the nanocrystals. The use of reactive trimethylsilyl reagents results in surface-limited reactions that shift the nanocrystal stoichiometry to anion-rich and improve epitaxial growth of the shell layer. In general, anion deposition on the InP QD surface results in a redshift in the absorption, quenching of the excitonic photoluminescence, and a relative increase in the intensity of broad trap-based photoluminescence, consistent with delocalization of the exciton wavefunction and relaxation of exciton confinement. Time-resolved photoluminescence data for the resulting InP/ZnSe QDs show an overall small change in the decay dynamics on the ns timescale, suggesting that the relatively low photoluminescence quantum yields may be attributed to the creation of new thermally activated charge trap states and likely a dark population that is inseparable from the emissive QDs. Cluster-model density functional theory calculations show that the presence of core/shell interface anions gives rise to electronic defects contributing to the redshift in the absorption. These results highlight a general strategy to atomistically tune the interfacial stoichiometry of InP QDs using surface-limited reaction chemistry allowing for precise correlations with the electronic structure and photophysical properties.

STratification risk analysis in OPerative management (STOP score) for drug-induced endocarditis.

BACKGROUND: The opioid epidemic has seen a drastic increase in the incidence of drug-associated infective endocarditis (IE). No clinical tool exists to predict operative morbidity and mortality in patients undergoing surgery. METHODS: A multi-institutional database was reviewed between 2011 and 2018. Multivariate logistic regression was fitted in an automated stepwise fashion. The STratification risk analysis in OPerative management of drug-associated IE (STOP) score was constructed. Morbidity was defined as reintubation, prolonged ventilation, pneumonia, renal failure, dialysis, stroke, reoperation for bleeding, and a permanent pacemaker. Cross-validation provided an unbiased estimate of out-of-sample performance. RESULTS: A total of 1181 patients underwent surgery for drug-associated IE (median age, 39; interquartile range [IQR], 30-54, 386 women [32.7%], 341 reoperations for prosthetic valve endocarditis [28.9%], 316 patients with multivalve disease [26.8%]). Operative morbidity and mortality were 41.1% and 5.9%, respectively. Predictors of morbidity were dialysis (95% confidence interval [CI], 1.16-2.82), emergent intervention (1.83-4.73), multivalve procedure (1.01-1.98), causative organisms other than Streptococcus (1.09-2.02), and type of valve procedure performed [aortic valve procedure (1.07-2.15), mitral valve replacement (1.03-2.05), tricuspid valve replacement (1.21-2.60)]. Predictors of mortality were dialysis (1.29-5.74), active endocarditis (1.32-83), lung disease (1.25-5.43), emergent intervention (1.69-6.60), prosthetic valve endocarditis (1.24-3.69), aortic valve procedure (1.49-5.92) and multivalve disease (1.00-2.95). Variables maximizing explanatory power were translated into a scoring system. Each point increased odds of morbidity and mortality by 22.0% and 22.4% with an accuracy of 94.0% and 94.1%, respectively. CONCLUSION: Drug-related IE is associated with significant morbidity and mortality. An easily-applied risk stratification score may aid in clinical decision-making.

Not Just Endocarditis: Hospitalizations for Selected Invasive Infections Among Persons With Opioid and Stimulant Use Diagnoses-North Carolina, 2010-2018.

BACKGROUND: While increases in overdoses, viral hepatitis, and endocarditis associated with drug use have been well-documented in North Carolina, the full scope of invasive drug-related infections (IDRIs) has not. We characterized trends in IDRIs among hospitalized patients in North Carolina. METHODS: We compared invasive infections that were related or not related to drug use among hospitalized patients aged 18-55 years based on retrospective review of administrative records from 2010-2018. Hospitalizations for endocarditis, central nervous system/spine infections, osteomyelitis, and septic arthritis were labeled as IDRIs if discharge codes included opioid and/or amphetamine misuse. Trends, rates, and distributions were calculated. RESULTS: Among 44 851 hospitalizations for the specified infections, 2830 (6.3%) were IDRIs. The proportion of infections attributable to drug use increased from 1.5% (2010) to 13.1% (2018), and the rate grew from 1.2 to 15.1 per 100 000. Compared with those who had non-drug-related infections, patients with IDRIs were younger (median age, 35 vs 46 years), more likely to be non-Hispanic white (81% vs 56%), and had longer hospitalizations (median, 8 vs 6 days). 43% of hospitalizations for IDRIs involved infective endocarditis. CONCLUSIONS: The rate of IDRIs in North Carolina increased substantially during 2010-2018, indicating an urgent need for enhanced infection prevention, harm reduction, and addiction services aimed at community and inpatient settings.

Complementary Fluorescence Emission and Second Harmonic Spectra Improve Bilayer Characterization.

Complementary investigation of Laurdan fluorescence emission and second harmonic (SH) spectra in nonpolar, protic and aprotic polar solvents and phospholipid bilayers was carried out. SH of spectra computed using methods familiar in electro spin resonance spectroscopy yielded better resolution. Spectra were fit to log-normal distributions. SH spectra showed presence of two emissions in protic polar and nonpolar solvents and in both bilayer gel and liquid phases and a single line in aprotic polar solvents. Each of the half maximal positions of each line in both homogenous solvents and bilayers, expresses similar linearity with peak position. This shared feature suggests planar and nonplanar Laurdan conformation respectively in the longer (red) and shorter (blue) wavelength emitting states. The weaker 432 nm blue line, not detected before in the gel phase, is distinguishable in the SH. Temperature trajectories of areas and peak positions of the individual lines bring new insight into the nature of lipid packing and evolution of domains, indicating inhomogeneous lipid packing even in the gel phase. The blue line identifies as emission from Laurdan in tighter packed regions and the dominant 445-448 nm red line in the gel phase shifting to 484 nm in the liquid phase as emission from Laurdan-water coupled states that are in varying stages of relaxation according to temperature and phase. Unexpected increase in the area of the blue line with temperature through the gel-liquid transition is consistent with coexisting low and high curvature domains and Laurdan's preference for less polar low curvature domains.

Trends in Drug Use-Associated Infective Endocarditis and Heart Valve Surgery, 2007 to 2017: A Study of Statewide Discharge Data.

Background: Drug use-associated infective endocarditis (DUA-IE) is increasing as a result of the opioid epidemic. Infective endocarditis may require valve surgery, but surgical treatment of DUA-IE has invoked controversy, and the extent of its use is unknown. Objective: To examine hospitalization trends for DUA-IE, the proportion of hospitalizations with surgery, patient characteristics, length of stay, and charges. Design: 10-year analysis of a statewide hospital discharge database. Setting: North Carolina hospitals, 2007 to 2017. Patients: All patients aged 18 years or older hospitalized for IE. Measurements: Annual trends in all IE admissions and in IE hospitalizations with valve surgery, stratified by patients' drug use status. Characteristics of DUA-IE surgical hospitalizations, including patient demographic characteristics, length of stay, disposition, and charges. Results: Of 22 825 IE hospitalizations, 2602 (11%) were for DUA-IE. Valve surgery was performed in 1655 IE hospitalizations (7%), including 285 (17%) for DUA-IE. Annual DUA-IE hospitalizations increased from 0.92 to 10.95 and DUA-IE hospitalizations with surgery from 0.10 to 1.38 per 100 000 persons. In the final year, 42% of IE valve surgeries were performed in patients with DUA-IE. Compared with other surgical patients with IE, those with DUA-IE were younger (median age, 33 vs. 56 years), were more commonly female (47% vs. 33%) and white (89% vs. 63%), and were primarily insured by Medicaid (38%) or uninsured (35%). Hospital stays for DUA-IE were longer (median, 27 vs. 17 days), with higher median charges ($250 994 vs. $198 764). Charges for 282 DUA-IE hospitalizations exceeded $78 million. Limitation: Reliance on administrative data and billing codes. Conclusion: DUA-IE hospitalizations and valve surgeries increased more than 12-fold, and nearly half of all IE valve surgeries were performed in patients with DUA-IE. The swell of patients with DUA-IE is reshaping the scope, type, and financing of health care resources needed to effectively treat IE. Primary Funding Source: National Institutes of Health.

Challenges Facing a Rural Opioid Epidemic: Treatment and Prevention of HIV and Hepatitis C.

PURPOSE OF REVIEW: This article reviews recent epidemiologic trends in HIV and hepatitis C virus (HCV) and strategies for treatment and prevention of these infections as they relate to the opioid epidemic. RECENT FINDINGS: Among people who inject drugs (PWID) in the United States (US), HIV diagnoses are decreasing, while HCV is increasing. Care for HIV and HCV relies heavily on specialist infrastructure, which is lacking in rural areas. Antiretrovirals for HIV and direct-acting antivirals for HCV are effective among PWID, yet multiple barriers make it difficult for rural injectors to access these treatments. Similarly, access to syringe service programs, medication-assisted therapy for opioid addiction, and pre-exposure prophylaxis for HIV are all limited in rural areas. Previous research on HIV and HCV among PWID has focused on urban or international populations, yet the US opioid epidemic is moving away from metropolitan centers. Increasing rurality of opioid injection brings unique challenges in treatment and prevention. Research into the care of HIV, HCV, and opioid use disorder among rural populations is urgently needed.

Pilot-tone-based self-homodyne detection using optical nonlinear wave mixing.

An all-optical pilot-tone-based self-homodyne detection scheme using nonlinear wave mixing is experimentally demonstrated. Two scenarios are investigated using (1) multiple wavelength-division-multiplexed channels with sufficient power of the pilot tones and (2) a single channel with a low-power pilot tone. The eye diagram and bit error rate of the system are studied by tuning various parameters such as pump power, relative phase, and pilot-to-signal ratio.

Orbital angular momentum beams generated by passive dielectric phase masks and their performance in a communication link.

We demonstrate the generation of orbital angular momentum (OAM) beams using high-efficient polarization-insensitive phase masks. The OAM beams generated by the phase masks are characterized in terms of their tolerance to misalignment (lateral displacement or tilt) between the incident beam and phase mask. For certain scenarios, our results show that (a) when the tilt angle is within the range of -20 to +20 deg, the crosstalk among modes is less than -15 dB; and (b) lateral displacement of 0.3 mm could cause a large amount of power leaked to adjacent modes. Finally, OAM beams generated by the phase masks are demonstrated over a two-channel OAM-multiplexing link, each channel carrying a 40 Gbit/s data stream. An optical signal-to-noise-ratio (OSNR) penalty of ∼1 dB is measured without crosstalk at the bit error rate (BER) of 3.8×10-3. With crosstalk, an OSNR penalty of <1.5 dB is observed at the same BER.

Spatial light structuring using a combination of multiple orthogonal orbital angular momentum beams with complex coefficients.

Analogous to time signals that can be composed of multiple frequency functions, we use uniquely structured orthogonal spatial modes to create different beam shapes. We tailor the spatial structure by judiciously choosing a weighted combination of multiple modal states within an orthogonal orbital angular momentum (OAM) basis set, creating desired beam intensity "shapes." The weights of the OAM beams to be combined forms a Fourier pair with the spatial intensity distribution in the azimuthal direction of the resultant beam. As an example, we simulate and experimentally create various beam shapes by designing the weights of the combined OAM beams. We also find that 6× higher localized power, as compared to traditional beam combining, could be achieved by coherently combining nine orthogonal OAM beams.

Experimental demonstration of phase-sensitive regeneration of a binary phase-shift keying channel without a phase-locked loop using Brillouin amplification.

All-optical phase regeneration of a binary phase-shift keying signal is demonstrated at 10-30 Gb/s without a phase-locked loop in a phase-sensitive amplification-based system using Brillouin amplification of the idler. The system achieves phase noise reduction of up to 56% and up to 11 dB OSNR gain at 10-5 bit error rate for the 10 Gb/s signal. The system's sensitivity to different parameters and stability is also evaluated.