Showing papers by "Michael Hughes published in 2021"

The role of chest ct in deciphering interstitial lung involvement: systemic sclerosis versus covid-19.

Abstract: OBJECTIVE: To identify the main computed tomography (CT) features that may help distinguishing a progression of interstitial lung disease (ILD) secondary to Systemic sclerosis (SSc) from COVID-19 pneumonia. METHODS: This multicentric study included 22 international readers divided in the radiologist group (RAD) and non-radiologist group (nRAD). A total of 99 patients, 52 with COVID-19 and 47 with SSc-ILD, were included in the study. RESULTS: Fibrosis inside focal ground glass opacities (GGO) in the upper lobes; fibrosis in the lower lobe GGO; reticulations in lower lobes (especially if bilateral and symmetrical or associated with signs of fibrosis) were the CT features most frequently associated with SSc-ILD. The CT features most frequently associated with COVID- 19 pneumonia were: consolidation (CONS) in the lower lobes, CONS with peripheral (both central/peripheral or patchy distributions), anterior and posterior CONS and rounded-shaped GGOs in the lower lobes. After multivariate analysis, the presence of CONS in the lower lobes (p < 0.0001) and signs of fibrosis in GGO in the lower lobes (p < 0.0001) remained independently associated with COVID-19 pneumonia or SSc-ILD, respectively. A predictive score was created which resulted positively associated with the COVID-19 diagnosis (96.1% sensitivity and 83.3% specificity). CONCLUSION: The CT differential diagnosis between COVID-19 pneumonia and SSc-ILD is possible through the combination the proposed score and the radiologic expertise. The presence of consolidation in the lower lobes may suggest a COVID-19 pneumonia while the presence of fibrosis inside GGO may indicate a SSc-ILD.

Safety and Efficacy of Starting Antiretroviral Therapy in the First Week of Life.

Abstract: BACKGROUND Early antiretroviral therapy (ART) is recommended for infants with human immunodeficiency virus (HIV) infection. However, few antiretroviral options are available for neonates. METHODS The Early Infant Treatment Study in Botswana tested HIV-exposed infants within 96 hours of birth, and HIV-infected infants started nevirapine (NVP) 6 mg/kg twice daily, zidovudine (ZDV), and lamivudine (3TC) at age < 7 days. NVP trough concentrations were tested at 1 and 2 weeks. NVP was switched to ritonavir-boosted lopinavir (LPV/r) at week 2, 3, 4, or 5 according to delivery gestational age. RESULTS Forty HIV-infected infants started ART at median age 2 days (range, 1-5 days). NVP trough concentrations were highly variable and below therapeutic target (3000 ng/mL) for 50% of 2-week measurements; concentrations did not correlate with viral decline at weeks 2, 4, or 12. Two deaths unrelated to ART occurred through 24 weeks. Only 1 unscheduled treatment modification was required. Within 4 weeks of transition to LPV/r, 9 (22.5%) had transient HIV RNA increases, likely due to poor LPV/r palatability. At 12 weeks, 22 (55%) of 40 were <40 copies/mL (93% <400 copies/mL); by 24 weeks, 27 of 38 (71%) were < 40 copies/mL (84% < 400 copies/mL). HIV-1 RNA response at 12 and 24 weeks did not differ by baseline HIV RNA or other factors. CONCLUSIONS NVP/ZDV/3TC started in the first week of life was safe and effective, even when trough NVP levels were below target. Transient viral increases occurred following transition to LPV/r, but by 12 and 24 weeks most children achieved and maintained viral suppression. CLINICAL TRIALS REGISTRATION NCT02369406.

The role of ultrasound in systemic sclerosis: On the cutting edge to foster clinical and research advancement:

Abstract: Ultrasound has been widely explored in systemic sclerosis in the clinical and research settings. Ultrasound allows a non-invasive and ionising radiation-free ‘window’ into this complex disease and ...

Use of dietary phytochemicals for inhibition of trimethylamine N-oxide formation.

Abstract: Trimethylamine-N-oxide (TMAO) has been reported as a risk factor for atherosclerosis development, as well as for other cardiovascular disease (CVD) pathologies. The objective of this review is to provide a useful summary on the use of phytochemicals as TMAO-reducing agents. This review discusses the main mechanisms by which TMAO promotes CVD, including the modulation of lipid and bile acid metabolism, and the promotion of endothelial dysfunction and oxidative stress. Current knowledge on the available strategies to reduce TMAO formation are discussed, highlighting the effect and potential of phytochemicals. Overall, phytochemicals (i.e., phenolic compounds or glucosinolates) reduce TMAO formation by modulating gut microbiota composition and/or function, inhibiting host's capacity to metabolize TMA to TMAO, or a combination of both. Perspectives for design of future studies involving phytochemicals as TMAO-reducing agents are discussed. Overall, the information provided by this review outlines the current state of the art of the role of phytochemicals as TMAO reducing agents, providing valuable insight to further advance in this field of study.

Prebiotic Inulin Supplementation and Peripheral Insulin Sensitivity in adults at Elevated Risk for Type 2 Diabetes: A Pilot Randomized Controlled Trial

Abstract: Prediabetes affects 84.1 million adults, and many will progress to type 2 diabetes (T2D). The objective of this proof-of-concept trial was to determine the efficacy of inulin supplementation to improve glucose metabolism and reduce T2D risk. Adults (n = 24; BMI: 31.3 ± 2.9 kg/m2; age: 54.4 ± 8.3 years) at risk for T2D were enrolled in this controlled feeding trial and consumed either inulin (10 g/day) or placebo (maltodextrin, 10 g/day) for six weeks. Assessments included peripheral insulin sensitivity, fasting glucose, and insulin, HOMA-IR, in vivo skeletal muscle substrate preference, Bifidobacteria copy number, intestinal permeability, and endotoxin concentrations. Participant retention was 92%. There were no baseline group differences except for fasting insulin (p = 0.003). The magnitude of reduction in fasting insulin concentrations with inulin (p = 0.003, inulin = Δ-2.9, placebo = Δ2.3) was attenuated after adjustment for baseline concentrations (p = 0.04). After adjusting for baseline values, reduction in HOMA-IR with inulin (inulin = Δ-0.40, placebo=Δ0.27; p = 0.004) remained significant. Bifidobacteria 16s increased (p = 0.04; inulin = Δ3.1e9, placebo = Δ-8.9e8) with inulin supplementation. Despite increases in gut Bifidobacteria, inulin supplementation did not improve peripheral insulin sensitivity. These findings question the need for larger investigations of inulin and insulin sensitivity in this population.

Considerations for a combined index for limited cutaneous systemic sclerosis to support drug development and improve outcomes

Abstract: Systemic sclerosis (SSc; systemic scleroderma) is characterized by a heterogeneous range of clinical manifestations. SSc is classified into limited cutaneous SSc (lcSSc) and diffuse cutaneous subgroups (dcSSc) based on the extent of skin involvement. Randomized controlled trials in scleroderma have mainly focused on dcSSc partly because the measurement of skin involvement, critical for evaluating a therapeutic intervention is more dynamic in this subset. Nonetheless, lcSSc, the most common cutaneous subset (about 2/3), is also associated with significant morbidity and detrimental impact on health-related quality of life. The lack of interventional studies in lcSSc is partly due to a lack of relevant outcome measures to evaluate this subgroup. Combining several clinically meaningful outcomes selected specifically for lcSSc may improve representativeness in clinical trials and responsiveness of outcomes measured in randomized controlled trials. A composite index dedicated to lcSSc combining such relevant outcomes could advance clinical trial development for lcSSc by providing the opportunity to test and select among candidate drugs that could act as disease-modifying treatments for this neglected subgroup of SSc. This proposed index would include items selected by expert physicians and patients with lcSSc across domains grounded in the lived experience of lcSSc. This article reviews the reasons behind the relative neglect of lcSSc, discusses the current state of outcome measures for lcSSc, identifies challenges, and proposes a roadmap for a combined lcSSc-specific treatment response index.

Emergence of SARS-CoV-2 Resistance with Monoclonal Antibody Therapy

Abstract: Resistance mutations to monoclonal antibody (mAb) therapy has been reported, but in the non-immunosuppressed population, it is unclear if in vivo emergence of SARS-CoV-2 resistance mutations alters either viral replication dynamics or therapeutic efficacy. In ACTIV-2/A5401, non-hospitalized participants with symptomatic SARS-CoV-2 infection were randomized to bamlanivimab (700mg or 7000mg) or placebo. Treatment-emergent resistance mutations were significantly more likely detected after bamlanivimab 700mg treatment than placebo (7% of 111 vs 0% of 112 participants, P=0.003). There were no treatment-emergent resistance mutations among the 48 participants who received bamlanivimab 7000mg. Participants with emerging mAb resistant virus had significantly higher pre-treatment nasopharyngeal and anterior nasal viral load. Intensive respiratory tract viral sampling revealed the dynamic nature of SARS-CoV-2 evolution, with evidence of rapid and sustained viral rebound after emergence of resistance mutations, and worsened symptom severity. Participants with emerging bamlanivimab resistance often accumulated additional polymorphisms found in current variants of concern/interest and associated with immune escape. These results highlight the potential for rapid emergence of resistance during mAb monotherapy treatment, resulting in prolonged high level respiratory tract viral loads and clinical worsening. Careful virologic assessment should be prioritized during the development and clinical implementation of antiviral treatments for COVID-19.

How do patients define Raynaud’s phenomenon? Differences between primary and secondary disease

Abstract: To examine how people define Raynaud’s phenomenon (RP) based on their lived experiences and explore if differences exist depending on primary or secondary RP diagnosis. An international survey was sent to people with RP through health systems, foundations, and social media. Qualitative coding of responses to an open text question regarding one’s own definition of RP was performed and themes were identified. The prevalence of themes among the sample and then comparisons between themes among people who self-reported primary versus secondary diagnosis of RP were performed. There were 1345 respondents from 45 countries (mean age 51.5 years, 93% female) who defined RP in their own words; 17% reported primary RP and 83% reported secondary RP (69% of secondary RP was scleroderma-related, n = 927). Over half defined their RP by describing the body parts affected, color changes, pain, and triggers or situations in which an episode occurs. Patients with primary RP more frequently defined RP in terms of its impact on function/quality of life and pain compared to those with secondary RP (34.5% versus 25.3%, respectively, p=0.004; 54.0% versus 46.8%, p=0.05). Patients with secondary RP more frequently included specific body parts, color change, the management of attacks, and other digital vascular complications in their definition of RP. We have identified differences in how people with primary and secondary RP define RP, in terms of how they feel and function. Our findings have implications for the domains of outcome measures for assessing RP within different patient populations.

ANCA in systemic sclerosis, when vasculitis overlaps with vasculopathy: a devastating combination of pathologies.

Abstract: In patients with systemic sclerosis (SSc), the coexistence of ANCA-associated vasculitis (SSc-AAV) has been reported to be associated with a severe disease course, including significant pulmonary and renal involvement. The presence of ANCA is not uncommon in patients with SSc and therefore clinicians must maintain a high index of clinical suspicion about SSc-AAV. p-ANCA and anti-MPO antibodies are the most common antibodies observed. Patients typically present with clinical features of microscopic polyangiitis or renal-limited vasculitis There are multiple areas of potential interaction in the pathogenesis of SSc and AAV which can exacerbate/compound vascular disease. In addition, similar patterns of major internal organ involvement (e.g., lung and kidneys) are seen in both conditions. We highlight a diagnostic approach to SSc-AAV and the paucity of data to inform management. As such, SSc-AAV is typically treated as per isolated AAV which can potentially be hazardous in patients with SSc (e.g., the association between high-dose steroid and scleroderma renal crisis). We propose that this rare clinical entity warrants rigorous investigation including definition of a therapeutic strategy to ameliorate the potentially devastating combination of pathologies in SSc-AAV.

Viral Reservoir in Early-Treated Human Immunodeficiency Virus-Infected Children and Markers for Sustained Viral Suppression.

Abstract: BACKGROUND The impact of very early infant treatment on human immunodeficiency virus (HIV) reservoir, and markers for treatment success, require study. METHODS The Early Infant Treatment Study (EIT) enrolled 40 children living with HIV started on antiretroviral treatment (ART) at <7 days of age, with 23 who had started treatment between 30-365 days to serve as controls. Quantitative HIV DNA was evaluated every 1-3 months in peripheral blood mononuclear cells. 84-week repeat qualitative whole blood DNA polymerase chain reaction and dual enzyme immunosorbent assay were performed. RESULTS Median quantitative cell-associated DNA after at least 84 weeks was significantly lower among the first 27 EIT children tested than among 10 controls (40.8 vs 981.4 copies/million cells; P < .001) and correlated with pre-ART DNA. Median DNA after 84 weeks did not differ significantly by negative or positive serostatus at 84 weeks (P = .94), and appeared unaffected by periods of unsuppressed plasma RNA from 24-84 weeks (P = .70). However, negative 84-week serostatus was 67% predictive for sustained RNA suppression, and positive serostatus was 100% predictive for viremia. Loss of qualitative DNA positivity at 84 weeks was 73% predictive for sustained suppression, and persistent positivity was 77% predictive for viremia. CONCLUSIONS Lower viral reservoir was associated with starting ART at <1 week. Negative serostatus and qualitative DNA were useful markers of sustained viral suppression from 24-84 weeks.

Digital Ulcers in Systemic Sclerosis.

Abstract: Digital ulcers (DU) are one of the most common complication of Systemic Sclerosis (SSc)-related vasculopathy and represent an important burden for the patients as well as for the society. Still today there is no agreement on the definition, classification and cathegorization of DU even if they are of pivotal importance in clinical practice, for treatment choice and prognostic outcomes, as well as for clinical trials. DU management requires a dedicated multidisciplinary team, that must remain ever vigilant for the development of infective complications and gangrene throughout their disease course, as well as patient education that is crucial to obtain the best compliance to assure the success of the treatment. Currently several drugs are available for DU treatment but in the future, more investigations will be needed to ameliorate the approach and the systemic and local therapies.

Impact of Covid-19 on clinical care and lived experience of systemic sclerosis: An international survey from EURORDIS-Rare Diseases Europe

Abstract: Introduction:Outcomes related to Covid-19 in systemic sclerosis patients could be influenced by internal organ involvement and/or immunosuppressive treatment, leading to efforts to shield patients

Domains and outcome measures for the assessment of limited cutaneous systemic sclerosis: a scoping review protocol

Abstract: Introduction Limited cutaneous systemic sclerosis (lcSSc) is the most frequent subset of systemic sclerosis. Despite this, lcSSc is not the major focus of clinical studies. The lack of interventional studies in lcSSc is due, in part, to a paucity of relevant outcome measures to effectively evaluate this subset. A combined response index dedicated to lcSSc would facilitate development of well-designed trials and approval of new drugs. The objective of this scoping review is to perform a broad and comprehensive identification of the outcome measures (core set items) within relevant domains, which have been used so far to assess lcSSc. Methods and analysis The planned scoping review will be based on the approach proposed by Arksey et al and further developed by Levac et al. Development and reporting will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-Extension for Scoping Reviews checklist and guidelines. The development of the search strategy was guided by the concepts of domains and outcomes based on the Outcome Measures in Rheumatology approach and by the different names and definitions of SSc, with a specific emphasis on their occurrence in clinical trial studies. Two databases will be searched: MEDLINE and Embase. Studies in English, published from the year 1988 onwards, will be included, since 1988 corresponds to the publication of LeRoy's first consensus definition of lcSSc. Data will be extracted and analysed using a standardised charting tool. Ethics and dissemination No ethical approval is required for this study. The results will be submitted to an international peer-reviewed journal and scientific conferences, informing the discussion on which items should be included in a combined response index dedicated to lcSSc (the CRISTAL project: Combined Response Index for Scleroderma Trial Assessing lcSSc).

Drug susceptibility patterns of Mycobacterium tuberculosis from adults with multidrug-resistant tuberculosis and implications for a household contact preventive therapy trial

Abstract: Drug susceptibility testing (DST) patterns of Mycobacterium tuberculosis (MTB) from patients with rifampicin-resistant tuberculosis (RR-TB) or multidrug-resistant TB (MDR-TB; or resistant to rifampicin and isoniazid (INH)), are important to guide preventive therapy for their household contacts (HHCs). As part of a feasibility study done in preparation for an MDR-TB preventive therapy trial in HHCs, smear, Xpert MTB/RIF, Hain MTBDRplus, culture and DST results of index MDR-TB patients were obtained from routine TB programs. A sputum sample was collected at study entry and evaluated by the same tests. Not all tests were performed on all specimens due to variations in test availability. Three hundred eight adults with reported RR/MDR-TB were enrolled from 16 participating sites in 8 countries. Their median age was 36 years, and 36% were HIV-infected. Routine testing on all 308 were confirmed as having RR-TB, but only 75% were documented as having MDR-TB. The majority of those not classified as having MDR-TB were because only rifampicin resistance was tested. At study entry (median 59 days after MDR-TB treatment initiation), 280 participants (91%) were able to produce sputum for the study, of whom 147 (53%) still had detectable MTB. All but 2 of these 147 had rifampicin DST done, with resistance detected in 89%. Almost half (47%) of the 147 specimens had INH DST done, with 83% resistance. Therefore, 20% of the 280 study specimens had MDR-TB confirmed. Overall, DST for second-line drugs were available in only 35% of the 308 routine specimens and 15% of 280 study specimens. RR-TB was detected in all routine specimens but only 75% had documented MDR-TB, illustrating the need for expanded DST beyond Xpert MTB/RIF to target preventive therapy for HHC.

Digital pitting scars are associated with a severe disease course and death in systemic sclerosis: a study from the EUSTAR cohort.

Abstract: OBJECTIVE Digital pitting scars (DPS) are frequent, but little studied in SSc to date. METHODS An analysis of SSc patients enrolled in the EUSTAR database. Primary objectives were to 1) examine DPS prevalence, 2) whether DPS are associated with digital ulcers (DUs) and active digital ischaemia (DUs or gangrene), and 3) describe other associations with DPS including internal organ complications. Secondary objectives were whether DPS are associated with 1) functional impairment, 2) structural microvascular disease, 3) and mortality. Descriptive statistics and parametric/non-parametric tests were used. Binary logistic regression was used to examine the association between DPS and DUs, active digital ischaemia, and mortality. RESULTS 9671 patients were included with reported DPS at any time point (n = 4924) or 'never' DPS (n = 4747). The majority (86.9%) were female and mean age was 55.7 years. DPS were associated with longer disease and Raynaud's duration (both P = <0.001). DPS were associated with interstitial lung disease, pulmonary hypertension, conduction blocks, telangiectases, calcinosis (all P = <0.001) and joint synovitis (P = <0.021). Patients were more likely to have more severe capillaroscopic abnormality and greater hand functional impairment. Multivariable logistic regression analyses showed that DPS were associated (OR) with DUs: 22.03 (19.51 to 24.87), active digital ischaemia: 6.30 (5.34 to 7.42), and death: 1.86 (1.48 to 2.36). CONCLUSION DPS are associated with a severe disease course including death. The impact of DPS on hand function and ischaemia is significant. The presence of DPS should alert the clinician to a poor prognosis and need to optimise the therapeutic strategy.

The Updated Role of Ultrasound in Assessing Dermatological Manifestations in Systemic Sclerosis

Abstract: Systemic sclerosis (SSc), an autoimmune connective tissue disease, characterized by skin fibrosis, increased dermal thickness and microvascular involvement. Fibroblasts and myofibroblasts deposit excessive amounts of collagenous and non-collagenous extracellular matrix components in the skin. This leads to microvascular abnormalities and Raynaud's phenomenon, with painful digital ulcers (DU) at the fingertips adding to patient discomfort. The skin involvement and severity in SSc was evaluated by the Modified Rodnan skin score (mRSS). Although high-frequency ultrasound (HUS) has been widely researched in the study of skin thickness and DU in SSc, its adoption into clinical practice is not yet common. However, novel insights into the still relatively unknown disease pathogenesis in SSc and its evaluation may be provided by HUS, including early (pre-clinical) skin involvement. It may also be useful in both the evaluation and follow-up of DU. Indeed, it is a non-invasive, safe, inexpensive and reproducible method able to assess not only SSc patients' cutaneous structural changes, but also their vascular system changes. Moreover, several recent studies have reported that elastosonography (ES) is of use when investigating skin involvement in systemic sclerosis. This review aims at providing information as to role HUS and ES play in research advancements and the clinical perspectives in the evaluation of skin thickness and DU in SSc patients.

Imaging digital arteries in systemic sclerosis by tomographic 3-dimensional ultrasound.

Abstract: Objective methods are needed to quantify digital artery disease in systemic sclerosis (SSc) for clinical trials of vascular therapies. Our primary aim was to examine feasibility of a novel tomographic three-dimensional-(3-D) ultrasound (tUS) with high-frequency ultrasound (HFUS) or ultra-high-frequency ultrasound (UHFUS) to assess the digital arteries in patients with SSc compared to healthy controls. A secondary objective was to compare the total wall volume (TWV) as a measure of intimal/medial thickness. Eighteen patients with a confirmed diagnosis of SSc were studied by tUS HFUS (17.5 MHz, n = 10) or tUS UHFUS (48 and 70 MHz, n = 8) with equal numbers of healthy controls of similar age and gender. The majority of patients had limited cutaneous SSc and were representative of a spectrum of digital vasculopathy, with over half (n = 6 HFUS and n = 5 UHFUS) having previous digital ulceration. Over half were receiving oral vasodilatory therapy. TWV was measured in both digital arteries of the middle finger bilaterally. At least, two digital arteries could be identified at 17.5 MHz in all patients and healthy controls. Whereas, at least two digital arteries could be identified in relatively fewer patients compared to healthy controls using 48 MHz (n = 6 and 10) and especially 70 MHz (n = 4 and 10) UHFUS. The median difference in TWV between patients and healthy controls was -6.49 mm3 using 17.5 MHz, 1.9 mm3 at 48 MHz, and -0.4 mm3 at 70 MHz. tUS using UHFUS is a feasible method to measure TWV of digital arteries in SSc. Transducer frequency plays an important factor in successful digital artery measurement, with 48 MHz being the optimal frequency.

Inline holographic microscopy through fiber imaging bundles

Abstract: Fiber imaging bundles are widely used as thin, passive image conduits for miniaturized and endoscopic microscopy, particularly for confocal fluorescence imaging. Holographic microscopy through fiber bundles is more challenging; phase conjugation approaches are complex and require extensive calibration. This paper describes how simple inline holographic microscopy can be performed through an imaging bundle using a partially coherent illumination source from a multimode fiber. The sample is imaged in transmission, with the intensity hologram sampled by the bundle and transmitted to a remote camera. The hologram can then be numerically refocused for volumetric imaging, achieving a resolution of approximately 6 µm over a depth range of 1 mm. The scheme does not require any complex prior calibration and hence is insensitive to bending.

Osteomyelitis Complicating Digital Ulcer Disease.

Abstract: D igital ulcers (DUs) are a major cause of hand-related pain and disability in patients with systemic sclerosis (SSc). Around half of patients with SSc report a history of DUs, and often ulcerate early in the course of the disease. In general, our current treatments to both prevent and heal DUs rely upon systemic vasodilation, including intravenously administered prostanoids. Digital ulcers are often infected, in particular by Staphylococcus aureus, and infection significantly delays ulcer healing. Other local DU complications include abscess/fistula development, necrosis, and deeper bony involvement (ie, osteomyelitis). A 60-year-old gentleman with late-onset Raynaud phenomenon developed recurrent digital ulceration and necrosis on the right middle finger after trivial trauma 1 month ago (panel A). There was no evidence of an underlying secondary cause including connective tissue disease such as SSc (eg, normal nailfold capillaroscopy and negative antinuclear antibody), and his Raynaud phenomenon was well controlled on oral sildenafil. At initial presentation, he was a heavy smoker (previously 20–30 cigarettes per day) but now uses an electronic cigarette. His digital lesion was associated with severe pain (which was sufficient to impair sleep), and there was significant swelling of the finger. He reported discharge of pus from the lesion and had received several courses of oral antibiotic therapy from his general practitioner without benefit. Investigations revealed an elevated C-reactive protein of 32 mg/L. Due to the refractory nature of his DU and the severity of the associated pain, we had a high clinical suspicion of osteomyelitis. Plain radiograph of the digit (panel B) confirmed osteomyelitis of the distal phalanx with established bone loss. He was promptly referred to our colleagues in orthopedic hand surgery and underwent surgical debridement of the ulcer. Osteomyelitis complicating digital ulceration in secondary Raynaud phenomenon is likely underrecognized. Osteomyelitis is often very challenging to diagnose in clinical

Resistance to Mycobacterium tuberculosis Infection Among Household Contacts: A Multinational Study.

Abstract: BACKGROUND Some contacts of patients with tuberculosis remain negative on tests for tuberculosis infection, despite prolonged exposure, suggesting they might be resistant to Mycobacterium tuberculosis infection. The objective of this multinational study was to estimate the proportion of household contacts resistant to M. tuberculosis (resisters). METHODS We conducted a longitudinal study enrolling index patients enrolled in treatment for pulmonary multidrug- or rifampin-resistant tuberculosis and their household contacts. Contacts were tested for tuberculosis infection with a tuberculin skin test (TST) and interferon-gamma release assay (IGRA) at baseline and after 1 year. Exposure was quantified based on index patients' infectiousness, index patient and household contact interaction, and age. We explored multiple definitions of resistance to tuberculosis infection by varying TST negativity cutoffs (0 vs <5 mm), classification of missing test results, and exposure level. RESULTS In total, 1016 contacts were evaluated from 284 households; 572 contacts aged ≥5 years had TST and longitudinal IGRA results available. And 77 (13%) or 71 (12%) contacts were classified as resisters with a <5 mm or 0 mm TST threshold, respectively. Among 263 highly exposed contacts, 29 (11%) or 26 (10%) were classified as resisters using TST cutoffs of <5 mm and 0 mm, respectively. The prevalence of resisters did not differ substantially by sex, age, human immunodeficiency virus (HIV) coinfection, or comorbid conditions. CONCLUSIONS At least 10% of household contacts can be classified as resistant to tuberculosis infection, depending on the definition used, including those with high exposure. Further studies to understand genetic or immunologic mechanisms underlying the resister phenotype may inform novel strategies for therapeutics and vaccines.

An Open-Source Monte Carlo Ray-Tracing Simulation Tool for Luminescent Solar Concentrators with Validation Studies Employing Scattering Phosphor Films

Abstract: Luminescent solar concentrators enhance the power output of solar cells through wave-guided luminescent emission and have great potential as building-integrated photovoltaics. Luminescent solar concentrators with a variety of geometries and absorbing–emitting materials have been reported in the literature. As the breadth of available experimental configurations continues to grow, there is an increasing need for versatile Monte Carlo ray-tracing simulation tools to analyze the performance of these devices for specific applications. This paper presents the framework for a Monte Carlo ray-tracing simulation tool that can be used to analyze a host of three-dimensional geometries. It incorporates custom radiative transport models to consider the effects of scattering from luminescent media, while simultaneously modeling absorption and luminescent emission. The model is validated using experimental results for three-dimensional planar and wedge-shaped luminescent solar concentrators employing scattering phosphor films. Performance was studied as a function of length, wavelength, and the angle of incidence of incoming light. The data for the validation studies and the code (written using the Python programming language) associated with the described model are publically available.

A Practical Approach to the Management of Digital Ulcers in Patients With Systemic Sclerosis: A Narrative Review.

Abstract: Importance Digital ulcers (DUs) occurring on the fingers in patients with systemic sclerosis (SSc) are associated with substantial pain and disability and are often challenging to treat. However, careful clinical assessment and prompt intervention (wound bed management and systemic pharmacologic treatment) may modify the clinical course. Objectives To provide a practical approach to the assessment and management of SSc-DUs and highlight unmet needs and research priorities. Evidence Review A narrative review of the extant literature was undertaken to provide a broad overview of current knowledge and augmented by expert opinion. Findings Half of the patients with SSc have a history of DUs, and there is a point of prevalence of approximately 10%. Digital ulcers are often very painful and affect all aspects of physical, social, and family life as well as occupation. Digital ulcers are associated with a severe disease course. Systemic sclerosis DUs, particularly those occurring on the fingertips, represent a vascular ischemic complication, although other etiopathogenic factors play an important role. To guide management, a structured clinical approach is required, including DU definition, classification, and categorization. Digital ulcers require a multidisciplinary approach with close cooperation between physicians and specialist nursing and other allied health professionals to guarantee the appropriate treatment and provide patient education. Local wound bed management is necessary for all DUs and is combined with systemic (pharmacologic) treatments. When treating a DU, the clinician should actively review the therapeutic strategy to prevent further DUs, including the level of systemic disease control, and monitor closely for the development of DU complications, including infection and progression to gangrene. Despite a wide available therapeutic armory, a number of unmet needs and challenges remain that that require resolution to optimize DU management. Conclusions and Relevance A practical approach to DU management, including local wound bed management and systemic treatments, is useful. Digital ulcers are of interest to a broad range of dermatologists, rheumatologists, and other physicians providing care for patients with SSc. Careful clinical assessment and prompt intervention can substantially modify the clinical course of DUs in SSc.

Antiretroviral hair levels, self-reported adherence, and virologic failure in second-line regimen patients in resource-limited settings.

Abstract: OBJECTIVE To evaluate associations between hair antiretroviral hair concentrations as an objective, cumulative adherence metric, with self-reported adherence and virologic outcomes. DESIGN Analysis of cohort A of the ACTG-A5288 study. These patients in resource-limited settings were failing second-line protease inhibitor-based antiretroviral therapy (ART) but were susceptible to at least one nucleoside reverse transcriptase inhibitor (NRTI) and their protease inhibitor, and continued taking their protease inhibitor-based regimen. METHODS Antiretroviral hair concentrations in participants taking two NRTIs with boosted atazanavir (n = 69) or lopinavir (n = 112) were analyzed at weeks 12, 24, 36 and 48 using liquid-chromatography--tandem-mass-spectrometry assays. Participants' self-reported percentage of doses taken in the previous month; virologic failure was confirmed HIV-1 RNA at least 1000 copies/ml at week 24 or 48. RESULTS From 181 participants with hair samples (61% women, median age: 39 years; CD4+ cell count: 167 cells/μl; HIV-1 RNA: 18 648 copies/ml), 91 (50%) experienced virologic failure at either visit. At 24 weeks, median hair concentrations were 2.95 [interquartile range (IQR) 0.49-4.60] ng/mg for atazanavir, 2.64 (IQR 0.73--7.16) for lopinavir, and 0.44 (IQR 0.11--0.76) for ritonavir. Plasma HIV-1 RNA demonstrated inverse correlations with hair levels (rs -0.46 to -0.74) at weeks 24 and 48. Weaker associations were seen with self-reported adherence (rs -0.03 to -0.24). Decreasing hair concentrations were significantly associated with virologic failure, the hazard ratio (95% CI) for ATV, LPV, and RTV were 0.69 (0.56-0.86), 0.77 (0.68-0.87), and 0.12 (0.06-0.27), respectively. CONCLUSION Protease inhibitor hair concentrations showed stronger associations with subsequent virologic outcomes than self-reported adherence in this cohort. Hair adherence measures could identify individuals at risk of second-line treatment failure in need of interventions.

Poor quality of life and incomplete self-reported adherence predict second-line ART virological failure in resource-limited settings.

Abstract: We evaluated health-related quality of life (QoL) and self-reported incomplete adherence as predictors of early second-line antiretroviral (ART) virological failure (VF). ACTG A5273 study participa...