Use of an extended KDIGO definition to diagnose acute kidney injury in patients with COVID-19: A multinational study using the ISARIC-WHO clinical characterisation protocol.

BACKGROUND: Acute kidney injury (AKI) is one of the most common and significant problems in patients with Coronavirus Disease 2019 (COVID-19). However, little is known about the incidence and impact of AKI occurring in the community or early in the hospital admission. The traditional Kidney Disease Improving Global Outcomes (KDIGO) definition can fail to identify patients for whom hospitalisation coincides with recovery of AKI as manifested by a decrease in serum creatinine (sCr). We hypothesised that an extended KDIGO (eKDIGO) definition, adapted from the International Society of Nephrology (ISN) 0by25 studies, would identify more cases of AKI in patients with COVID-19 and that these may correspond to community-acquired AKI (CA-AKI) with similarly poor outcomes as previously reported in this population. METHODS AND FINDINGS: All individuals recruited using the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC)-World Health Organization (WHO) Clinical Characterisation Protocol (CCP) and admitted to 1,609 hospitals in 54 countries with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection from February 15, 2020 to February 1, 2021 were included in the study. Data were collected and analysed for the duration of a patient's admission. Incidence, staging, and timing of AKI were evaluated using a traditional and eKDIGO definition, which incorporated a commensurate decrease in sCr. Patients within eKDIGO diagnosed with AKI by a decrease in sCr were labelled as deKDIGO. Clinical characteristics and outcomes-intensive care unit (ICU) admission, invasive mechanical ventilation, and in-hospital death-were compared for all 3 groups of patients. The relationship between eKDIGO AKI and in-hospital death was assessed using survival curves and logistic regression, adjusting for disease severity and AKI susceptibility. A total of 75,670 patients were included in the final analysis cohort. Median length of admission was 12 days (interquartile range [IQR] 7, 20). There were twice as many patients with AKI identified by eKDIGO than KDIGO (31.7% versus 16.8%). Those in the eKDIGO group had a greater proportion of stage 1 AKI (58% versus 36% in KDIGO patients). Peak AKI occurred early in the admission more frequently among eKDIGO than KDIGO patients. Compared to those without AKI, patients in the eKDIGO group had worse renal function on admission, more in-hospital complications, higher rates of ICU admission (54% versus 23%) invasive ventilation (45% versus 15%), and increased mortality (38% versus 19%). Patients in the eKDIGO group had a higher risk of in-hospital death than those without AKI (adjusted odds ratio: 1.78, 95% confidence interval: 1.71 to 1.80, p-value < 0.001). Mortality and rate of ICU admission were lower among deKDIGO than KDIGO patients (25% versus 50% death and 35% versus 70% ICU admission) but significantly higher when compared to patients with no AKI (25% versus 19% death and 35% versus 23% ICU admission) (all p-values <5 × 10-5). Limitations include ad hoc sCr sampling, exclusion of patients with less than two sCr measurements, and limited availability of sCr measurements prior to initiation of acute dialysis. CONCLUSIONS: An extended KDIGO definition of AKI resulted in a significantly higher detection rate in this population. These additional cases of AKI occurred early in the hospital admission and were associated with worse outcomes compared to patients without AKI.

Effect of nasal balloon autoinflation in children with otitis media with effusion in primary care: an open randomized controlled trial.

BACKGROUND: Otitis media with effusion is a common problem that lacks an evidence-based nonsurgical treatment option. We assessed the clinical effectiveness of treatment with a nasal balloon device in a primary care setting. METHODS: We conducted an open, pragmatic randomized controlled trial set in 43 family practices in the United Kingdom. Children aged 4-11 years with a recent history of ear symptoms and otitis media with effusion in 1 or both ears, confirmed by tympanometry, were allocated to receive either autoinflation 3 times daily for 1-3 months plus usual care or usual care alone. Clearance of middle-ear fluid at 1 and 3 months was assessed by experts masked to allocation. RESULTS: Of 320 children enrolled, those receiving autoinflation were more likely than controls to have normal tympanograms at 1 month (47.3% [62/131] v. 35.6% [47/132]; adjusted relative risk [RR] 1.36, 95% confidence interval [CI] 0.99 to 1.88) and at 3 months (49.6% [62/125] v. 38.3% [46/120]; adjusted RR 1.37, 95% CI 1.03 to 1.83; number needed to treat = 9). Autoinflation produced greater improvements in ear-related quality of life (adjusted between-group difference in change from baseline in OMQ-14 [an ear-related measure of quality of life] score -0.42, 95% CI -0.63 to -0.22). Compliance was 89% at 1 month and 80% at 3 months. Adverse events were mild, infrequent and comparable between groups. INTERPRETATION: Autoinflation in children aged 4-11 years with otitis media with effusion is feasible in primary care and effective both in clearing effusions and improving symptoms and ear-related child and parent quality of life. TRIAL REGISTRATION: ISRCTN, No. 55208702.

Diffuse transition state structure for the unfolding of a leucine-rich repeat protein.

Tandem-repeat proteins, such as leucine-rich repeats, comprise arrays of small structural motifs that pack in a linear fashion to produce elongated architectures. They lack contacts between residues that are distant in primary sequence, a feature that distinguishes them from the complex topologies of globular proteins. Here we have investigated the unfolding pathway of the leucine-rich repeat domain of the mRNA export protein TAP (TAPLRR) using Φ-value analysis. Whereas most of the tandem-repeat proteins studied to date have been found to unfold via a polarised mechanism in which only a small, localised number of repeats are structured in the transition state, the unfolding mechanism of TAPLRR is more diffuse in nature. In the transition state for unfolding of TAPLRR, three of the four LRRs are highly structured and non-native interactions are formed within the N-terminal α-helical cap and the first LRR. Thus, the α-helical cap plays an important role in which non-native interactions are required to provide a scaffold for the LRRs to pack against in the folding reaction.

Long Covid: a global health issue - a prospective, cohort study set in four continents.

INTRODUCTION: A proportion of people develop Long Covid after acute COVID-19, but with most studies concentrated in high-income countries (HICs), the global burden is largely unknown. Our study aims to characterise long-term COVID-19 sequelae in populations globally and compare the prevalence of reported symptoms in HICs and low-income and middle-income countries (LMICs). METHODS: A prospective, observational study in 17 countries in Africa, Asia, Europe and South America, including adults with confirmed COVID-19 assessed at 2 to <6 and 6 to <12 months post-hospital discharge. A standardised case report form developed by International Severe Acute Respiratory and emerging Infection Consortium's Global COVID-19 Follow-up working group evaluated the frequency of fever, persistent symptoms, breathlessness (MRC dyspnoea scale), fatigue and impact on daily activities. RESULTS: Of 11 860 participants (median age: 52 (IQR: 41-62) years; 52.1% females), 56.5% were from HICs and 43.5% were from LMICs. The proportion identified with Long Covid was significantly higher in HICs vs LMICs at both assessment time points (69.0% vs 45.3%, p<0.001; 69.7% vs 42.4%, p<0.001). Participants in HICs were more likely to report not feeling fully recovered (54.3% vs 18.0%, p<0.001; 56.8% vs 40.1%, p<0.001), fatigue (42.9% vs 27.9%, p<0.001; 41.6% vs 27.9%, p<0.001), new/persistent fever (19.6% vs 2.1%, p<0.001; 20.3% vs 2.0%, p<0.001) and have a higher prevalence of anxiety/depression and impact on usual activities compared with participants in LMICs at 2 to <6 and 6 to <12 months post-COVID-19 hospital discharge, respectively. CONCLUSION: Our data show that Long Covid affects populations globally, manifesting similar symptomatology and impact on functioning in both HIC and LMICs. The prevalence was higher in HICs versus LMICs. Although we identified a lower prevalence, the impact of Long Covid may be greater in LMICs if there is a lack of support systems available in HICs. Further research into the aetiology of Long Covid and the burden in LMICs is critical to implement effective, accessible treatment and support strategies to improve COVID-19 outcomes for all.

Urine collection devices to reduce contamination in urine samples for diagnosis of uncomplicated UTI: a single-blind randomised controlled trial in primary care.

BACKGROUND: Urine collection devices (UCDs) are being marketed and used in clinical settings to reduce urine sample contamination, despite inadequate supporting evidence. AIM: To determine whether UCDs, compared with standardised instructions for urine sample collection, reduce the proportion of contaminated samples. DESIGN AND SETTING: Single-blind randomised controlled trial in general practices in England and Wales. METHOD: Women aged ≥18 years presenting with symptoms attributable to urinary tract infection (UTI) were randomised (1:1:1) to use either a Peezy UCD or a Whiz Midstream UCD, or were given standardised verbal instructions (SVI) for midstream sample collection. The primary outcome was the proportion of urine samples reported as contaminated by microbiology laboratory analysis. RESULTS: A total of 1264 women (Peezy UCD: n = 424; Whiz Midstream UCD: n = 421; SVI: n = 419) were randomised between October 2016 and August 2018. Ninety women were excluded from the primary analysis as a result of ineligibility or lack of primary outcome data, leaving 1174 (Peezy UCD: n = 381; Whiz Midstream UCD: n = 390; SVI: n = 403) for intention-to-treat analysis. The proportion of contaminated samples was 26.5% with the Peezy UCD, 28.2% with the Whiz Midstream UCD, and 29.0% with SVI (relative risk: Peezy UCD versus SVI = 0.91, 95% CI = 0.76 to 1.09, P = 0.32; Whiz Midstream UCD versus SVI = 0.98, 95% CI = 0.97 to 1.20, P = 0.82). There were 100 (25.3%) device failures with the Peezy UCD and 35 (8.8%) with the Whiz Midstream UCD; the proportion of contaminated samples was similar after device failure samples were excluded. CONCLUSION: Neither the Peezy UCD nor the Whiz Midstream UCD reduced urine sample contamination when used by women presenting to primary care with suspected UTI. Their use cannot be recommended for this purpose in this setting.

ISARIC-COVID-19 dataset: A Prospective, Standardized, Global Dataset of Patients Hospitalized with COVID-19.

The International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) COVID-19 dataset is one of the largest international databases of prospectively collected clinical data on people hospitalized with COVID-19. This dataset was compiled during the COVID-19 pandemic by a network of hospitals that collect data using the ISARIC-World Health Organization Clinical Characterization Protocol and data tools. The database includes data from more than 705,000 patients, collected in more than 60 countries and 1,500 centres worldwide. Patient data are available from acute hospital admissions with COVID-19 and outpatient follow-ups. The data include signs and symptoms, pre-existing comorbidities, vital signs, chronic and acute treatments, complications, dates of hospitalization and discharge, mortality, viral strains, vaccination status, and other data. Here, we present the dataset characteristics, explain its architecture and how to gain access, and provide tools to facilitate its use.

The Suspected CANcer (SCAN) pathway: protocol for evaluating a new standard of care for patients with non-specific symptoms of cancer.

INTRODUCTION: Cancer survival in England lags behind most European countries, due partly to lower rates of early stage diagnosis. We report the protocol for the evaluation of a multidisciplinary diagnostic centre-based pathway for the investigation of 'low-risk but not no-risk' cancer symptoms called the Suspected CANcer (SCAN) pathway. SCAN is a new standard of care being implemented in Oxfordshire; one of a number of pathways implemented during the second wave of the Accelerate, Coordinate, Evaluate (ACE) programme, an initiative which aims to improve England's cancer survival rates through establishing effective routes to early diagnosis. METHODS AND ANALYSIS: To evaluate SCAN, we are collating a prospective database of patients referred onto the pathway by their general practitioner (GP). Patients aged over 40 years, with non-specific symptoms such as weight loss or fatigue, who do not meet urgent cancer referral criteria or for whom symptom causation remains unclear after investigation via other existing pathways, can be referred to SCAN. SCAN provides rapid CT scanning, laboratory testing and clinic review within 2 weeks. We will follow all patients in the primary and secondary care record for at least 2 years. The data will be used to understand the diagnostic yield of the SCAN pathway in the short term (28 days) and the long term (2 years). Routinely collected primary and secondary care data from patients not referred to SCAN but with similar symptoms will also be used to evaluate SCAN. We will map the routes to diagnosis for patients referred to SCAN to assess cost-effectiveness. Acceptability will be evaluated using patient and GP surveys. ETHICS AND DISSEMINATION: The Oxford Joint Research Office Study Classification Group has judged this to be a service evaluation and so outside of research governance. The results of this project will be disseminated by peer-reviewed publication and presentation at conferences.

Activation of ubiquitin ligase SCF(Skp2) by Cks1: insights from hydrogen exchange mass spectrometry.

Skp2 is the substrate recognition subunit of the multi-subunit ubiquitin ligase SCF(Skp2). It consists of an N-terminal F-box domain that binds to the Skp1 subunit and thereby tethers it to the SCF catalytic core, and an elongated C-terminal domain comprising ten Leucine-rich repeats (LRR) that binds the substrate. A small accessory protein, Cks1, is required for SCF(Skp2) to target certain substrates, including the Cyclin-dependent kinase inhibitor p27. Here we have used hydrogen/deuterium exchange monitored by mass spectrometry to investigate the mode of action of Cks1 on SCF(Skp2). We show that complex formation between Cks1 and Skp2 causes conformational changes in both proteins in regions distant from the respective binding sites. We find that Skp2 interacts with a localised region of Cks1 but the interaction causes a global change in the hydrogen exchange behaviour of Cks1. Also, whilst Cks1 binds to the most C-terminal LRRs of the elongated Skp2 molecule, the interaction induces conformational changes at the distant N-terminal LRRs, close to the F-box motif. Further, binding of Cks1 to Skp2 significantly stabilises the interaction between Skp2 and Skp1. The results reveal that the C-terminal substrate recognition region of Skp2 is coupled to the N-terminal Skp1-binding region and thereby to the SCF catalytic core; this result adds to the model proposed previously that, whilst the principal function of the F-box protein is to recruit the substrate, an additional function may be to help position the substrate in an optimal way within the SCF complex to enable efficient ubiquitin transfer.

An open randomised study of autoinflation in 4- to 11-year-old school children with otitis media with effusion in primary care.

BACKGROUND: Otitis media with effusion (OME) is a very common problem in primary care, but one that lacks an evidence-based non-surgical treatment. OBJECTIVE: To determine the clinical effectiveness of nasal balloon autoinflation for the treatment of OME in children. DESIGN: A pragmatic, two-arm, open randomised controlled trial. SETTING: Forty-three general practices from 17 UK primary care trusts recruited between January 2012 and February 2013. PARTICIPANTS: School children aged 4-11 years with a history of OME symptoms or related concerns in the previous 3 months, and a type B tympanogram, diagnostic of a middle ear effusion, in one or both ears. INTERVENTION: Three hundred and twenty children were randomised, 160 to each group, using independent web-based computer-generated randomisation (with minimisation based on age, sex and baseline severity of OME) to either nasal balloon autoinflation performed three times per day for 1-3 months plus usual care, or usual care alone. MAIN OUTCOME MEASURES: The proportion of children demonstrating clearance of middle ear fluid in at least one ear (with normal tympanograms) at 1 and 3 months, assessed blind to treatment. An ear-related measure of quality of life (QoL) [a 14-point questionnaire on the impact of OME (OMQ-14)], weekly diary recorded symptoms, compliance and adverse events were all secondary outcomes. RESULTS: At 1 month, the proportion of children with normal tympanograms was 47.3% (62/131) in those allocated to autoinflation and 35.6% (47/132) in those receiving usual care [adjusted relative risk (RR) 1.36, 95% confidence interval (CI) 0.99 to 1.88]. At 3 months, the proportions were 49.6% (62/125) and 38.3% (46/120), respectively (adjusted RR 1.37, 95% CI 1.03 to 1.83; number needed to treat = 9). The change in OMQ-14 also favoured the intervention arm (adjusted global score difference -0.42; p = 0.001). Reported compliance was good: 89% in the first month and 80% in months 2 and 3. Adverse events included otalgia in 4% of treated children compared with 1% in the control group. Minor nosebleeds (14% vs. 15%) and respiratory tract infections (18% vs. 13%) were noted. CONCLUSION: We found the use of autoinflation in young children with OME to be feasible in primary care and effective in both clearing effusions and improving child and parent ear-related QoL and symptoms. This method has scope to be used more widely. Further research is needed for very young children, and to inform prudent use in different health settings.

Folding and fibril formation of the cell cycle protein Cks1.

The Saccharomyces cerevisiae Cks protein Cks1 has a COOH-terminal glutamine-rich sequence not present in other homologues. Cks proteins domain swap to form dimers but unique to Cks1 is the anti-parallel arrangement of protomers within the dimer. Despite the differences in Cks1 compared with other Cks proteins, we find the domain swapping properties are very similar. However, aggregation of Cks1 occurs by a route distinct from the other Cks proteins studied to date. Cks1 formed fibrillar aggregates at room temperature and neutral pH. During this process, Cks1 underwent proteolytic cleavage at a trypsin-like site into two fragments, the globular Cks domain and the glutamine-rich COOH terminus. At high protein concentrations, the rate of fibril formation was the same as the rate of proteolysis. The dominant species present within the fibrils was the glutamine-rich sequence. Consistent with this result, fibril formation was enhanced by addition of trypsin. Moreover, a truncated variant lacking the glutamine-rich sequence did not form fibrils under the same conditions. A lag phase at low protein concentrations indicates that fibril formation occurs through a nucleation and growth mechanism. The aggregates appear to resemble amyloid fibrils, in that they show the typical cross-beta x-ray diffraction pattern. Moreover, infrared spectroscopy data indicate that the glutamine side chains are hydrogen-bonded along the axis of the fibril. Our results indicate that the proteolytic reaction is the crucial step initiating aggregation and demonstrate that Cks1 is a simple, tunable model system for exploring aggregation mechanisms associated with polyglutamine deposition diseases.

Role of conformational heterogeneity in domain swapping and adapter function of the Cks proteins.

Cks proteins are adapter molecules that coordinate the assembly of multiprotein complexes. They share the ability to domain swap by exchanging a beta-strand, beta4. Here we use NMR spectroscopy and molecular dynamics simulations to investigate the dynamic properties of human Cks1 and its response on assembly with components of the SCF(Skp2) ubiquitin ligation machinery. In the NMR experiment with the free form of Cks1, a subset of residues displayed elevated R2 values and the cross-peaks of neighboring residues were missing from the spectrum, indicating a substantial conformational exchange contribution on the microsecond to millisecond time scale. Strikingly the region of greatest conformational variability was the beta4-strand that domain swaps to form the dimer. Binding of the ligand common to all Cks proteins, Cdk2, suppressed the conformational heterogeneity. This response was specific to Cdk2 binding; in contrast, binding of Skp2, a ligand unique to human Cks1, did not alter the dynamic behavior. Short time (<5 ns) molecular dynamics simulations indicate that residues of Cks1 that form the binding site for phosphorylated ligands are considerably more flexible in the free form of Cks1 than they are in the Cdk2-Cks1 complex. A cooperative interaction between Cdk2 and Cks1 is suggested, which reduces the configurational entropy of Cks1 and therefore facilitates phosphoprotein binding. Indications of an unusual dynamic behavior of strand beta4 in the free form of Cks1 were obtained from longer time scale (50 ns) dynamics simulations. A spontaneous reversible unzipping of hydrogen bonds between beta4 and beta2 was observed, suggesting an early intermediate structure for unfolding and/or domain swapping. We propose that the dynamic properties of the beta-sheet and its modification upon ligand binding underlie the domain swapping ability and the adapter function of Cks proteins.