Postoperative Staphylococcus aureus Infections in Patients With and Without Preoperative Colonization.

Importance: Staphylococcus aureus surgical site infections (SSIs) and bloodstream infections (BSIs) are important complications of surgical procedures for which prevention remains suboptimal. Contemporary data on the incidence of and etiologic factors for these infections are needed to support the development of improved preventive strategies. Objectives: To assess the occurrence of postoperative S aureus SSIs and BSIs and quantify its association with patient-related and contextual factors. Design, Setting, and Participants: This multicenter cohort study assessed surgical patients at 33 hospitals in 10 European countries who were recruited between December 16, 2016, and September 30, 2019 (follow-up through December 30, 2019). Enrolled patients were actively followed up for up to 90 days after surgery to assess the occurrence of S aureus SSIs and BSIs. Data analysis was performed between November 20, 2020, and April 21, 2022. All patients were 18 years or older and had undergone 11 different types of surgical procedures. They were screened for S aureus colonization in the nose, throat, and perineum within 30 days before surgery (source population). Both S aureus carriers and noncarriers were subsequently enrolled in a 2:1 ratio. Exposure: Preoperative S aureus colonization. Main Outcomes and Measures: The main outcome was cumulative incidence of S aureus SSIs and BSIs estimated for the source population, using weighted incidence calculation. The independent association of candidate variables was estimated using multivariable Cox proportional hazards regression models. Results: In total, 5004 patients (median [IQR] age, 66 [56-72] years; 2510 [50.2%] female) were enrolled in the study cohort; 3369 (67.3%) were S aureus carriers. One hundred patients developed S aureus SSIs or BSIs within 90 days after surgery. The weighted cumulative incidence of S aureus SSIs or BSIs was 2.55% (95% CI, 2.05%-3.12%) for carriers and 0.52% (95% CI, 0.22%-0.91%) for noncarriers. Preoperative S aureus colonization (adjusted hazard ratio [AHR], 4.38; 95% CI, 2.19-8.76), having nonremovable implants (AHR, 2.00; 95% CI, 1.15-3.49), undergoing mastectomy (AHR, 5.13; 95% CI, 1.87-14.08) or neurosurgery (AHR, 2.47; 95% CI, 1.09-5.61) (compared with orthopedic surgery), and body mass index (AHR, 1.05; 95% CI, 1.01-1.08 per unit increase) were independently associated with S aureus SSIs and BSIs. Conclusions and Relevance: In this cohort study of surgical patients, S aureus carriage was associated with an increased risk of developing S aureus SSIs and BSIs. Both modifiable and nonmodifiable etiologic factors were associated with this risk and should be addressed in those at increased S aureus SSI and BSI risk.

Hepmarc: A 96 week randomised controlled feasibility trial of add-on maraviroc in people with HIV and non-alcoholic fatty liver disease.

OBJECTIVES: Maraviroc may reduce hepatic inflammation in people with HIV and non-alcoholic fatty liver disease (HIV-NAFLD) through CCR5-receptor antagonism, which warrants further exploration. METHODS: We performed an open-label 96-week randomised-controlled feasibility trial of maraviroc plus optimised background therapy (OBT) versus OBT alone, in a 1:1 ratio, for people with virologically-suppressed HIV-1 and NAFLD without cirrhosis. Dosing followed recommendations for HIV therapy in the Summary of Product Characteristics for maraviroc. The primary outcomes were safety, recruitment and retention rates, adherence and data completeness. Secondary outcomes included the change in Fibroscan-assessed liver stiffness measurements (LSM), controlled attenuation parameter (CAP) and Enhanced Liver Fibrosis (ELF) scores. RESULTS: Fifty-three participants (53/60, 88% of target) were recruited; 23 received maraviroc plus OBT; 89% were male; 19% had type 2 diabetes mellitus. The median baseline LSM, CAP & ELF scores were 6.2 (IQR 4.6-7.8) kPa, 325 (IQR 279-351) dB/m and 9.1 (IQR 8.6-9.6) respectively. Primary outcomes: all individuals eligible after screening were randomised; there was 92% (SD 6.6%) adherence to maraviroc [target >90%]; 83% (95%CI 70%-92%) participant retention [target >65%]; 5.5% of data were missing [target <20%]. There were noo Serious Adverse Reactions; mild-moderate intensity Adverse Reactions were reported by five participants (5/23, 22% (95%CI 5%-49%)) [target <10%]. All Adverse Reactions resolved. Secondary outcomes: no important differences were seen by treatment group for the change from baseline in LSM, CAP or ELF scores. CONCLUSIONS: This feasibility study provides preliminary evidence of maraviroc safety amongst people with HIV-NAFLD, and acceptable recruitment, retention, and adherence rates. These data support a definitive randomised-controlled trial assessing maraviroc impact on hepatic steatosis and fibrosis. TRIAL REGISTRATION: Clinical trial registry: ISCRTN, registration number 31461655.

Increasing concentration of pure micro- and macro-LDPE and PP plastic negatively affect crop biomass, nutrient cycling, and microbial biomass.

Over the last 50 years, the intense use of agricultural plastic in the form of mulch films has led to an accumulation of plastic in soil, creating a legacy of plastic in agricultural fields. Plastic often contains additives, however it is still largely unknown how these compounds affect soil properties, potentially influencing or masking effects of the plastic itself. Therefore, the aim of this study was to investigate the effects of pure plastics of varying sizes and concentrations, to improve our understanding of plastic-only interactions within soil-plant mesocosms. Maize (Zea mays L.) was grown over eight weeks following the addition of micro and macro low-density polyethylene and polypropylene at increasing concentrations (equivalent to 1, 10, 25, and 50 years mulch film use) and the effects of plastic on key soil and plant properties were measured. We found the effect of both macro and microplastic on soil and plant health is negligible in the short-term (1 to <10 years). However, ≥ 10 years of plastic application for both plastic types and sizes resulted in a clear negative effect on plant growth and microbial biomass. This study provides vital insight into the effect of both macro and microplastics on soil and plant properties.

Liver steatosis and fibrosis in people with human immunodeficiency virus in West Africa and the relationship with hepatitis B virus coinfection.

There is a heavy burden of liver disease in West Africa. While the role of hepatitis B virus (HBV) infection is well recognized, less is known about the contributing role of liver steatosis and how the two interact in the context of human immunodeficiency virus (HIV) infection. Adults with HIV in Ghana underwent FibroScan measurements to determine prevalence of liver steatosis (expressed as controlled attenuation parameter [CAP]) and fibrosis (expressed as liver stiffness [LS]). We explored contributing factors in linear regression models, including demographics, lifestyle characteristics, medical history, HIV and HBV status, and measurements of metabolic syndrome. Among 329 adults (72.3% women; median age, 47 years), 322 (97.9%) were on antiretroviral therapy (median duration, 8.9 years). CD4 counts were preserved (median, 619 cells/mm3 ); plasma HIV RNA was fully suppressed in 162 (50.3%) of the treated participants. Cigarette smoking, excessive alcohol consumption, and use of traditional or herbal remedies were uncommon (6.1%, 1.8%, 3.3%, respectively). Largely undiagnosed metabolic syndrome was detected in 87 (26.4%) participants. We obtained readings indicative of ≥S2 steatosis and ≥F2 fibrosis in 43 (13.1%) and 55 (16.7%) participants, respectively. Higher CAP values were associated with metabolic syndrome and longer prior stavudine exposure. Higher LS values were associated with male sex, higher HIV RNA, and higher CAP values. Relative to people without HBV, those with HBV (n = 90) had a similar prevalence of ≥S2 steatosis but a higher prevalence of ≥F2 fibrosis (36.7% vs. 9.2%, p < 0.0001) and concomitant ≥S2 steatosis and ≥F2 fibrosis (9.1% vs. 1.3%, p < 0.001). Conclusion: Both HBV and liver steatosis pose a threat to long-term liver health among people with HIV in West Africa. Urgently required interventions include improving HIV suppression and diagnosing and managing determinants of the metabolic syndrome.

Iron-Modified Biochar Strengthens Simazine Adsorption and Decreases Simazine Decomposition in the Soil.

Currently, modified biochar has been successfully used in the remediation of soil polluted with heavy metals. However, the effects of the modified biochar on pesticides (such as simazine) are still unclear. Herein, the environmental fate of simazine, such as decomposition, leaching, and adsorption in unamended soil, in the soil amended with unmodified and modified biochar (biochar + FeCl3, biochar + FeOS, biochar + Fe) were evaluated. In addition, an incubation experiment was also performed to observe the influence of modified biochar on the microbial community and diversity in the soil. The results showed that modified biochar significantly decreased the decomposition of simazine in the soil compared to its counterpart. Modified biochar also reduced the concentration of simazine in the leachate. Compared with the control, soil microbial biomass in the soil amended with unmodified biochar, biochar + FeCl3, biochar + Fe, and biochar + FeOS was decreased by 5.3%, 18.8%, 8.7%, and 18.1%, respectively. Furthermore, modified biochar changed the structure of the microbial community. This shows that modified biochar could increase the soil adsorption capacity for simazine and change the amount and microbial community that regulates the fate of simazine in the soil. This study concludes that iron-modified biochar has positive and negative effects on the soil. Therefore, its advantages and side effects should be considered before applying it to the soil.

Genetic Variants of APOL1 Are Major Determinants of Kidney Failure in People of African Ancestry With HIV.

Introduction: Variants of the APOL1 gene are associated with chronic kidney disease (CKD) in people of African ancestry, although evidence for their impact in people with HIV are sparse. Methods: We conducted a cross-sectional study investigating the association between APOL1 renal risk alleles and kidney disease in people of African ancestry with HIV in the UK. The primary outcome was end-stage kidney disease (ESKD; estimated glomerular filtration rate [eGFR] of <15 ml/min per 1.73 m2, chronic dialysis, or having received a kidney transplant). The secondary outcomes included renal impairment (eGFR <60 ml/min per 1.73 m2), albuminuria (albumin-to-creatinine ratio [ACR] >30 mg/mmol), and biopsy-proven HIV-associated nephropathy (HIVAN). Multivariable logistic regression was used to estimate the associations between APOL1 high-risk genotypes (G1/G1, G1/G2, G2/G2) and kidney disease outcomes. Results: A total of 2864 participants (mean age 48.1 [SD 10.3], 57.3% female) were genotyped, of whom, 354 (12.4%) had APOL1 high-risk genotypes, and 99 (3.5%) had ESKD. After adjusting for demographic, HIV, and renal risk factors, individuals with APOL1 high-risk genotypes were at increased odds of ESKD (odds ratio [OR] 10.58, 95% CI 6.22-17.99), renal impairment (OR 5.50, 95% CI 3.81-7.95), albuminuria (OR 3.34, 95% CI 2.00-5.56), and HIVAN (OR 30.16, 95% CI 12.48-72.88). An estimated 49% of ESKD was attributable to APOL1 high-risk genotypes. Conclusion: APOL1 high-risk genotypes were strongly associated with kidney disease in people of African ancestry with HIV and accounted for approximately half of ESKD cases in this cohort.

Uncertainties in direct N2O emissions from grazing ruminant excreta (EF3PRP) in national greenhouse gas inventories.

Excreta deposition onto pasture, range and paddocks (PRP) by grazing ruminant constitute a source of nitrous oxide (N2O), a potent greenhouse gas (GHG). These emissions must be reported in national GHG inventories, and their estimation is based on the application of an emission factor, EF3PRP (proportion of nitrogen (N) deposited to the soil through ruminant excreta, which is emitted as N2O). Depending on local data available, countries use various EF3PRPs and approaches to estimate N2O emissions from grazing ruminant excreta. Based on ten case study countries, this review aims to highlight the uncertainties around the methods used to account for these emissions in their national GHG inventories, and to discuss the efforts undertaken for considering factors of variation in the calculation of emissions. Without any local experimental data, 2006 the IPCC default (Tier 1) EF3PRPs are still widely applied although the default values were revised in 2019. Some countries have developed country-specific (Tier 2) EF3PRP based on local field studies. The accuracy of estimation can be improved through the disaggregation of EF3PRP or the application of models; two approaches including factors of variation. While a disaggregation of EF3PRP by excreta type is already well adopted, a disaggregation by other factors such as season of excreta deposition is more difficult to implement. Empirical models are a potential method of considering factors of variation in the establishment of EF3PRP. Disaggregation and modelling requires availability of sufficient experimental and activity data, hence why only few countries have currently adopted such approaches. Replication of field studies under various conditions, combined with meta-analysis of experimental data, can help in the exploration of influencing factors, as long as appropriate metadata is recorded. Overall, despite standard IPCC methodologies for calculating GHG emissions, large uncertainties and differences between individual countries' accounting remain to be addressed.

Implied consent for HIV testing in the UK: time for a new approach?

Despite HIV infection being a treatable chronic illness and the many advances in testing for HIV, late diagnosis is still common, with associated avoidable morbidity and mortality. Requirements for explicit consent for HIV testing in the UK differ from those for other blood tests and are major barriers to testing. We argue that the disparity is illogical and outdated. We propose a model for normalising HIV testing that allows for routine testing in various health-care settings via implied consent, where other blood tests are performed. Inclusion of testing for hepatitis B and hepatitis C might also be incorporated into this model. The ethical argument for this approach is principally beneficence towards people with undiagnosed infection and the people they might infect. Patient autonomy would be maintained using systems allowing for individuals to opt out of implied consent.

Endocarditis and the impact of intravenous drug use: a cohort study.

OBJECTIVES: This cohort study is a comparison of infective endocarditis in intravenous drug users (IDUs) and non-IDUs within a single tertiary centre. We aim to quantify and describe the factors that influence prognosis and microbiological characteristics. METHOD: All consecutive admissions to a tertiary referral hospital in the north of England with a diagnosis of endocarditis from April 2013 to January 2020 were identified. Outcomes were all-cause mortality at 30 days, 12 months and 3 years, length of stay and progression to surgery. RESULTS: A total of 303 cases were identified via clinical coding of which 287 cases of endocarditis were confirmed. First episode endocarditis was then confirmed in 263 episodes, 44 in IDUs and 219 in non-IDUs. Methicillin sensitive Staphylococcus aureus (MSSA) was the most common organism seen overall, significantly more so in IDU than non-IDU cases (29/44 [65.9%] vs. 51/219 [23.3%], p < .001). Overall progression to valve surgery was similar between the two groups (92/219 [42.0%] vs. 19/44[43.2%], p = .886). In IDUs 30-d survival was 93% (80-98) and 3-year survival 47% (30-63%). In non-IDU 30-d survival was 88% (83-92%) and 60% (53-67%) at 3 years. Of the 19 IDUs who underwent valve surgery 7 (37%) survived to study completion without reinfection and 8 (42%) died following recurrent endocarditis. CONCLUSIONS: We demonstrate that prognosis in IDUs is worse than previously described, particularly in those undergoing valve surgery. This is despite comparable receipt of inpatient treatment to non-IDUs as demonstrated by equal length of stay and rates of surgery. Clinicians should consider the role of addictions services on discharge to break the cycle of reinfection.

Substrate control of sulphur utilisation and microbial stoichiometry in soil: Results of 13C, 15N, 14C, and 35S quad labelling.

Global plant sulphur (S) deficiency is increasing because of a reduction in sulphate-based fertiliser application combined with continuous S withdrawal during harvest. Here, we applied 13C, 15N, 14C, and 35S quad labelling of the S-containing amino acids cysteine (Cys) and methionine (Met) to understand S cycling and microbial S transformations in the soil. The soil microorganisms absorbed the applied Cys and Met within minutes and released SO42- within hours. The SO42- was reutilised by the MB within days. The initial microbial utilisation and SO42- release were determined by amino acid structure. Met released 2.5-fold less SO42- than Cys. The microbial biomass retained comparatively more C and S from Met than Cys. The microorganisms decomposed Cys to pyruvate and H2S whereas they converted Met to α-ketobutyrate and S-CH3. The microbial stoichiometries of C, N, and S derived from Cys and Met were balanced after 4 d by Cys-derived SO42- uptake and Met-derived CO2 release. The microbial C:N:S ratio dynamics showed rapid C utilisation and loss, stable N levels, and S accumulation. Thus, short-term organic S utilisation by soil microorganisms is determined by amino acid structure whilst long-term organic S utilisation by soil microorganisms is determined by microbially controlled stoichiometry.

Using an electronic health record alert to prompt blood-borne virus testing in primary care.

BACKGROUND: Late diagnosis of HIV, hepatitis B (HBV) and hepatitis C (HCV) remains relatively common in the UK and many people who present late have missed opportunities for testing in primary care. The objective was to assess the effectiveness and acceptance of a prototype application (BBV_TP1), embedded in a primary care electronic health record (EHR), to increase real-time blood-borne virus (BBV) testing. METHODS: This prospective cohort study assessed BBV_TP1 in 14 general practices in North East England, in comparison with 54 similar practices in 2019. Rates of HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) testing in practices were measured before and after the application was activated. Patient and clinician acceptance of the technology was assessed by surveys. RESULTS: In the 6 months following the intervention, HIV testing rates increased 555% and combined HBV/HCV testing rates increased 362%. No significant differences were observed for any BBV testing rates in the nonintervention practices over the same period. Monthly testing rates declined towards baseline after initial increases. Clinician's perceptions of the prompt system were positive, with average additional time required for BBV test discussion in consultations estimated at 2 min. The patient survey also showed high acceptance of the technology. CONCLUSION: This pilot study demonstrated that BBV_TP1 increased BBV testing rates in primary care via targeted screening, although testing rates subsequently fell whilst the application remained active. Such systems can potentially reduce late diagnoses, while having high acceptance by clinicians and patients. Larger studies with longer follow-up are needed to demonstrate efficacy and cost-effectiveness.

Presentation and outcome of COVID-19 in HIV patients with high viral loads and opportunistic infections: a case series.

Coronavirus disease 2019 (COVID-19) is especially severe in patients with underlying chronic conditions, with increased risk of mortality. There is concern that people living with HIV (PLWH), especially those with severe immunosuppression, and COVID-19 may have severe disease and a negative clinical outcome. Most studies on COVID-19 in PLWH are from Asia, Europe and America where population dynamics, antiretroviral treatment coverage and coexisting opportunistic infections may differ from that in sub-Saharan Africa. We report on the clinical profile and outcome of three cases of PLWH co-infected with SARS-CoV-2. They all presented with fever, cough and breathlessness and also had advanced HIV infection as evidenced by opportunistic infections, high HIV viral loads and low CD4 counts. The patients responded favourably to the standard of care and were discharged home. Our findings suggest that PLWH with advanced immunosuppression may not necessarily have an unfavourable disease course and outcome. However, case-controlled studies with a larger population size are needed to better understand the impact of COVID-19 in this patient population. FUNDING: Not declared.

Impact of water table levels and winter cover crops on greenhouse gas emissions from cultivated peat soils.

Drainage and cultivation have turned peatlands from carbon (C) sinks into hotspots for greenhouse gas (GHG) emissions. Raising the water table and planting of winter cover crops are potential strategies to help reduce peat oxidation and re-initiate net C accumulation during the non-cropping period. However, the effects of these practices as well as their interactions on GHG emissions remain unclear. Here, we carried out an outdoor mesocosm experiment to elucidate the effect of water table levels (-30 cm and -50 cm) and winter cover crop cultivation (vetch, rye, no plant) on carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) fluxes during the winter period (November-April). Soil-atmosphere GHG exchange, GHG concentrations within the peat profile and soil water solute concentrations were monitored. Our results showed that high water table significantly reduced ecosystem respiration, while it had no net effect on N2O and CH4 fluxes. Uptake of available N by the cover crop significantly reduced nitrate in soil solution, thereby lowering the potential for leaching and both direct and indirect N2O emissions. No interactive effects between water table levels and cover crops were detected for any of the measured GHG fluxes. Seasonal variations of GHG fluxes were positively correlated with soil air concentrations at -15 cm and -40 cm depths, which were further regulated by dissolved organic C, nitrate concentration, and anaerobic conditions in the soil. This study suggests that there is great potential to raise water table levels and introduce green cover crops to reduce GHG emissions. Further studies are needed to achieve a complete evaluation of these strategies outside of the growing season, which may provide a significant mitigation benefit in C-rich cultivated peatlands.

Pyogenic brain abscess and subdural empyema: presentation, management, and factors predicting outcome.

PURPOSE: To describe the presentation and management of bacterial brain abscess and subdural empyema in adults treated at two tertiary centers. In addition, to identify factors that may predict a poor clinical outcome. METHODS: A retrospective analysis of data obtained from clinical records was performed, followed by multivariate regression analysis of patient and treatment-related factors. RESULTS: 113 patients were included with a median age of 53 years and a male preponderance. At presentation symptoms were variable, 28% had a focal neurological deficit, and 39% had a reduced Glasgow coma scale (GCS). Brain abscesses most frequently affected the frontal, temporal, and parietal lobes while 36% had a subdural empyema. An underlying cause was identified in 76%; a contiguous ear or sinus infection (43%), recent surgery or trauma (18%) and haematogenous spread (15%). A microbiological diagnosis was confirmed in 86%, with streptococci, staphylococci, and anaerobes most frequently isolated. Treatment involved complex, prolonged antibiotic therapy (> 6 weeks in 84%) combined with neurosurgical drainage (91%) and source control surgery (34%). Mortality was 5% with 31% suffering long-term disability and 64% achieving a good clinical outcome. A reduced GCS, focal neurological deficit, and seizures at presentation were independently associated with an unfavorable clinical outcome (death or disability). CONCLUSIONS: Complex surgical and antimicrobial treatment achieves a good outcome in the majority of patients with bacterial brain abscess and subdural empyema. Factors present at diagnosis can help to predict those likely to suffer adverse outcomes. Research to determine optimal surgical and antibiotic management would be valuable.

Fosfomycin vs. quinolone-based antibiotic prophylaxis for transrectal ultrasound-guided biopsy of the prostate: a systematic review and meta-analysis.

BACKGROUND: Infection-related complications secondary to quinolone resistance have been on the rise following transrectal ultrasound-guided biopsy of the prostate (TRUSBP). The aim of this review was to compare the efficacy of fosfomycin with quinolone-based antibiotic prophylaxis for TRUSBP. METHODS: A systematic review in line with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) and Cochrane guidelines was conducted. All studies comparing fosfomycin vs. non-fosfomycin antimicrobial prophylaxis for TRUSBP were considered. The main outcomes were number of urinary tract infections (UTIs) (overall, afebrile, febrile, and urosepsis) and fluoroqinolone resistance. Secondary outcomes were positive urine and blood cultures, and adverse effects of drugs. RESULTS: Five studies comparing fosfomycin and non-fosfomycin antimicrobials were included in the review. In all, 1447 and 1665 patients were included in the fosfomycin and non-fosfomycin cohorts, respectively. The systematic review report significantly lower UTIs in the fosfomycin cohort (M-H, Fixed, 95% CI), 0.20 (0.13, 0.30), p < 0.00001. Urine cultures from patients given fosfomycin showed significantly lower resistance rates (M-H, Fixed, 95% CI) 0.27 (0.15, 0.50), p < 0.0001. The adverse effect profile between the two cohorts were similar (M-H, Fixed, 95% CI) 1.13 (0.51, 2.50), p = 0.33. On Grade Pro evaluation, overall UTI, afebrile UTI, febrile UTI, and urosepsis were rates as moderate, low, very low, and moderate quality evidence, respectively. Positive blood and urine culture were rated as moderate and very low-quality evidence, respectively. Fluoroquinolone resistance was rated as low-quality evidence. Adverse effects was rated as very low-quality evidence. CONCLUSIONS: This review suggests that fosfomycin has significantly lower septic complications with an equivalent side effect profile in comparison with quinolone-based prophylaxis regimen for TRUSBP. There is an urgent need for appropriate antibiotic stewardship and it is paramount that studies with robust methodology are developed to establish the role of fosfomycin over existing antibiotic regimens for TRUSBP.

Hepatitis C Virus (HCV) RNA screening and sequencing using dry plasma spots.

BACKGROUND: HCV RNA screening of large sample repositories provides data on HCV epidemic patterns that may help guide control policies. In resource-limited settings, shipment of frozen samples to molecular laboratory facilities and testing of individual samples may be prohibitively expensive. OBJECTIVE: Our aim was to detect and sequence HCV RNA in a large HIV-positive cohort from Kumasi, Ghana, using pooled and individual dried plasma spots (DPS) produced from samples stored at -80°C. STUDY DESIGN: In the validation phase, replicate DPS were prepared with six dilutions (500-10,000 IU/ml) of the 4th International Standard for HCV and tested in three independent experiments. In the testing phase, DPS prepared with plasma samples from 875 HIV-positive subjects were pooled for screening, followed by testing of individual DPS of positive pools. Input from individual DPS was two 6mm punches; pools comprised two punches from each of five DPS. Genotypes were determined by Sanger sequencing of HCV core and NS5B. RESULTS: With the dilution series, sensitivity of HCV RNA detection was ≥2500 IU/ml. Replicate DPS gave intra-assay and inter-assay coefficients of variation ≤1.4%. With the stored samples, HCV RNA was detected in 5/175 DPS pools and in one DPS from each positive pool, yielding a HCV RNA prevalence of 5/875 (0.57%; 95% confidence interval 0.07-1.07%). The five samples were sequenced as HCV genotypes 2l and 2r. DISCUSSION: DPS allowed reproducible HCV RNA detection, and pooling effectively contained the cost and labour of screening a previously untested, low-prevalence cohort. DPS were also suitable for HCV sequencing.

Exploring the acceptability of a 'limited patient consent procedure' for a proposed blood-borne virus screening programme: a Delphi consensus building technique.

OBJECTIVE: To identify components of a proposed blood-borne virus (BBV) population screening programme and its associated consent procedure that both the public and health practitioners (HPs) would find acceptable. The proposed BBV screening system would aim to reduce late diagnosis of BBVs and be used in patients undergoing routine blood tests, aided by risk stratification software to target individuals at higher risk of infection. DESIGN: A Delphi technique was used to build consensus among two separate groups, public participants and HPs in England. METHODS: A survey incorporating vignettes was developed, with input from an external panel of experts. Over three rounds, 46 public participants and 37 HPs completed the survey, rating statements on a four-point Likert scale. The survey covered issues around stigma and sensitivity, the use of risk stratification algorithms and 'limited' patient consent (ie, preinformed of the option to 'opt-out'). Consensus was defined as >70% of participants agreeing or disagreeing with each statement. RESULTS: Consensus was achieved among both groups in terms of acceptability of the screening programme. There was also consensus on using patient data to risk-stratify screening algorithms and the need to obtain some form of consent around the time of drawing blood. CONCLUSIONS: This study found that the special protected status of HIV in England is no longer deemed necessary today and hinders appropriate care. We propose that a novel 'limited consent procedure' could be implemented in future screening programmes.

Hypocalcaemia and permanent hypoparathyroidism after total/bilateral thyroidectomy in the BAETS Registry.

The UK Registry of Endocrine and Thyroid Surgeons (UKRETS) has been operated by the British Association of Endocrine and Thyroid Surgeons (BAETS) and Dendrite Clinical Systems Ltd. in a web-based electronic format since 2004. Data on over 90,000 endocrine procedures have been collected to date. Analysis of those cases undergoing bilateral thyroid resections in the interval July 2010 to June 2015 demonstrates that hypocalcaemia remains the commonest complication of thyroid surgery. After first-time total thyroidectomy, 23.6% of patients develop hypocalcaemia, defined as a serum calcium <2.10 mmol/L (or <1.20 mmol/L ionized calcium) on the first post-operative day. Most require treatment with calcium +/- vitamin D supplements, with around 38% of all patients being treated by the time of discharge from the index admission. By 6 months post-operative, 7.3% of patients remain on calcium/vitamin D supplements, reflecting persistent (though not necessarily permanent) hypoparathyroidism. Risk factors for persistent hypocalcaemia are principally concomitant level VI lymph node dissection [odds ratio (OR) =2.73]; re-operative surgery (OR =1.44); and inter-surgeon variation.

Assessment of bioavailable organic phosphorus in tropical forest soils by organic acid extraction and phosphatase hydrolysis.

Soil organic phosphorus contributes to the nutrition of tropical trees, but is not accounted for in standard soil phosphorus tests. Plants and microbes can release organic anions to solubilize organic phosphorus from soil surfaces, and synthesize phosphatases to release inorganic phosphate from the solubilized compounds. We developed a procedure to estimate bioavailable organic phosphorus in tropical forest soils by simulating the secretion processes of organic acids and phosphatases. Five lowland tropical forest soils with contrasting properties (pH 4.4-6.1, total P 86-429 mg P kg- 1) were extracted with 2 mM citric acid (i.e., 10 µmol g- 1, approximating rhizosphere concentrations) adjusted to soil pH in a 4:1 solution to soil ratio for 1 h. Three phosphatase enzymes were then added to the soil extract to determine the forms of hydrolysable organic phosphorus. Total phosphorus extracted by the procedure ranged between 3.22 and 8.06 mg P kg- 1 (mean 5.55 ± 0.42 mg P kg- 1), of which on average three quarters was unreactive phosphorus (i.e., organic phosphorus plus inorganic polyphosphate). Of the enzyme-hydrolysable unreactive phosphorus, 28% was simple phosphomonoesters hydrolyzed by phosphomonoesterase from bovine intestinal mucosa, a further 18% was phosphodiesters hydrolyzed by a combination of nuclease from Penicillium citrinum and phosphomonoesterase, and the remaining 51% was hydrolyzed by a broad-spectrum phytase from wheat. We conclude that soil organic phosphorus can be solubilized and hydrolyzed by a combination of organic acids and phosphatase enzymes in lowland tropical forest soils, indicating that this pathway could make a significant contribution to biological phosphorus acquisition in tropical forests. Furthermore, we have developed a method that can be used to assess the bioavailability of this soil organic phosphorus.