Antidote removal during haemodialysis for massive acetaminophen overdose

CONTEXT

Haemodialysis is sometimes used for patients with massive acetaminophen overdose when signs of "mitochondrial paralysis" (lactic acidosis, altered mental status, hypothermia and hyperglycaemia) are present. The role of haemodialysis is debated, in part because the evidence base is weak and the endogenous clearance of acetaminophen is high. There is also concern because the antidote acetylcysteine is also dialyzable. We prospectively measured serum acetylcysteine concentrations during haemodialysis in three such cases.

CASE DETAILS

Three adults each presented comatose and acidemic 10 to ~18 h after ingesting > 1000mg/kg of acetaminophen. Two were hypothermic and hyperglycaemic. Serum lactate concentrations ranged from 7 mM to 12.5 mM. All three were intubated, and initial acetaminophen concentrations were as high as 5980 μM (900 μg/mL). An intravenous loading dose of 150 mg/kg acetylcysteine was initiated between 10.8 and ~18 h post ingestion, and additional doses were empirically administered during haemodialysis to compensate for possible antidote removal. A single run of 3-4 h of haemodialysis removed 10-20 g of acetaminophen (48-80% of remaining body burden), reduced serum acetaminophen concentrations by 56-84% (total clearance 3.4-7.8 mL/kg/min), accelerated native acetaminophen clearance (mean elimination half-life 580 min pre-dialysis, 120 min during and 340 min post-dialysis) and corrected acidemia. Extraction ratios of acetylcysteine across the dialysis circuit ranged from 73% to 87% (dialysance 3.0 to 5.3 mL/kg/min). All three patients recovered fully, and none developed coagulopathy or other signs of liver failure.

DISCUSSION

When massive acetaminophen ingestion is accompanied by coma and lactic acidosis, emergency haemodialysis can result in rapid biochemical improvement. As expected, haemodialysis more than doubles the clearance of both acetaminophen and acetylcysteine. Because acetylcysteine dosing is largely empirical, we recommend doubling the dose during haemodialysis, with an additional half-load when dialysis exceeds 6 h.

Exploring the migration decisions of health workers and trainees from Africa: a meta-ethnographic synthesis

The migration of healthcare workers from Africa depletes countries already suffering from substantial staffing shortages and considerable disease burdens. The recruitment of such individuals by high income countries has been condemned by the World Health Organisation. However, understanding the reasons why healthcare workers migrate is essential, in order to attempt to alter migration decisions. We aimed to systematically analyse factors influencing healthcare workers' decisions to migrate from Africa. We systematically searched CINAHL (1980-Nov 2010), Embase (1980-Nov 2010), Global Health (1973-Nov 2010) and Medline (1950-Nov 2010) for qualitative studies of healthcare workers from Africa which specifically explored views about migration. Two reviewers identified articles, extracted data and assessed quality of included studies. Meta-ethnography was used to synthesise new lines of understanding and meaning from the data. The search identified 1203 articles from which we included six studies of healthcare workers trained in seven African countries, namely doctors or medical students (two studies), nurses (three), and pharmacy students (one study). Using meta-ethnographic synthesis we produced six lines of argument relating to the migration decisions of healthcare workers: 1) Struggle to realise unmet material expectations of self, family and society, 2) Strain and emotion, interpersonal discord, and insecurity in workplace, 3) Fear from threats to personal or family safety, in and out of workplace, 4) Absence of adequate professional support and development, 5) Desire for professional prestige and respect, 6) Conviction that hopes and goals for the future will be fulfilled overseas. We conclude that a complex interaction of factors contribute to the migration decisions of healthcare workers from Africa. Some of the factors identified are more amenable to change than others, and addressing these may significantly affect migration decisions of African healthcare workers in the future.

Barriers to, and facilitators of, parenting programmes for childhood behaviour problems: a qualitative synthesis of studies of parents' and professionals' perceptions

Disruptive behaviour problems (DBPs) during childhood exert a high burden on individuals, families and the community as a whole. Reducing this impact is a major public health priority. Early parenting interventions are recommended as valuable ways to target DBPs; however, low take-up of, and high drop-out rates from, these programmes seriously reduce their effectiveness. We present a review of published qualitative evidence relating to factors that block or facilitate access and engagement of parents with such programmes using a thematic synthesis approach. 12 papers presenting views of both parents and professionals met our inclusion and quality criteria. A large number of barriers were identified highlighting the array of challenges parents can face when considering accessing and engaging with treatment for their child with behavioural problems. Facilitating factors in this area were also identified. A series of recommendations were made with regard to raising awareness of programmes and recruiting parents, providing flexible and individually tailored support, delivering programmes through highly skilled, trained and knowledgeable therapists, and highlighting factors to consider when delivering group-based programmes. Clinical guidelines should address barriers and facilitators of engagement as well as basic efficacy of treatment approaches.

Embolisation of type 2 endoleaks after endovascular aneurysm repair

Endovascular treatment has become the preferred method of repair of abdominal and thoracic aortic aneurysms, and comes with a unique complication in the form of endoleaks (type I-IV). Type II endoleaks are the focus of this review. They are the most common form of endoleak detected in CT surveillance following endovascular repair. They are observed in 9% to 30% of patients after abdominal endovascular repair (EVR), and 1.4% following thoracic endovascular aortic repair (TEVR). They are classified as primary or secondary, depending on when they are identified following EVR. Typically, retrograde filling of the aneurysm sac is caused by single or multiple, patent feeding vessels. Despite its relative frequency, there is a lack of consensus on the threshold at which treatment should be considered. The aims of treatment are to halt sac expansion or to prevent rupture. A majority of patients may be managed conservatively. In those that are treated, the most common form of management is single vessel embolization. As we will discuss here, there are several ways of performing this procedure, based on the site of endoleak, and causative vessel. Possible reasons for poor success rates will also be discussed. A general consensus on how to best manage these patients is yet to be reached. The aim of this review is to give an overview of type II endoleaks, their natural history and vessels most commonly involved, as well as different approaches to embolisation.

Modeling the Residence Time Distribution of a Non-Intermeshing Twin Screw Extruder

The residence time distribution (RTD) of a counter-rotating non-intermeshing twin screw extruder has been studied by a radioactive tracer technique. RTDs were measured at both the die exit and at the first compounding zone of the extruder. The operating parameters investigated were: screw speed, screw flight stagger, and barrel temperature. These parameters have an effect on the mixing efficiency. The mixing efficiency was characterized by fitting measured response data with models comprised of different combinations of ideal reactor elements. The empirical flow models tested were: plug flow and tanks-in-series (with and without recirculation), plug flow and axial dispersion, and the Wolf-Resnick model. The fitted model parameters characterized the observed changes in the RTD due to the variation of the operating parameters.

Prenatal diagnosis and outcome of absent pulmonary valve syndrome: contemporary single-center experience and review of the literature

OBJECTIVE

To review the anomaly spectrum of prenatally detected absent pulmonary valve syndrome (APVS) and the outcome after diagnosis. Previous fetal studies reported survival rates of ≤ 25% for patients with intended postnatal care.

METHODS

Clinical data and echocardiograms of 12 cases with a fetal diagnosis of APVS between 2000 and 2010 were analyzed in this retrospective single-center study. Collected parameters included: gestational age at referral, associated fetal abnormalities, cardiothoracic ratio, maximum diameters of pulmonary annulus and main and branch pulmonary arteries, ventricular dimensions and function as well as ventricular Doppler flows. Karyotyping included fluorescence in-situ hybridization (FISH) analysis for microdeletion 22q11.2.

RESULTS

Median gestational age at diagnosis was 24 weeks. Three subtypes of APVS were observed: (1) with tetralogy of Fallot (TOF) and no arterial duct (n = 10; 83%); (2) isolated, with a large arterial duct (n = 1; 8%); and (3) with tricuspid atresia, right ventricular dysplasia and a restricted duct (n = 1; 8%). The cardiothoracic ratio and pulmonary artery dimensions were increased in all cases. The karyotype was abnormal in 70% of fetuses with TOF and their mortality rate was significantly higher due to pregnancy termination (n = 3) or perinatal demise (n = 2) (hazard ratio, 5; 95% CI, 0.87-28.9; P = 0.015). Of seven live births with active postnatal care, six children (86%) were alive without residual respiratory symptoms at a median follow-up of 4.7 (range, 2.1-10.6) years.

CONCLUSION

Outcome after fetal diagnosis of APVS was significantly better in this study compared with those of previous fetal series, with a low mortality rate for actively managed patients.

Evidence for non-communicable diseases: analysis of Cochrane reviews and randomised trials by World Bank classification

INTRODUCTION

Prevalence of non-communicable diseases (NCDs) is increasing globally, with the greatest projected increases in low-income and middle-income countries. We sought to quantify the proportion of Cochrane evidence relating to NCDs derived from such countries.

METHODS

We searched the Cochrane database of systematic reviews for reviews relating to NCDs highlighted in the WHO NCD action plan (cardiovascular, cancers, diabetes and chronic respiratory diseases). We excluded reviews at the protocol stage and those that were repeated or had been withdrawn. For each review, two independent researchers extracted data relating to the country of the corresponding author and the number of trials and participants from countries, using the World Bank classification of gross national income per capita.

RESULTS

797 reviews were analysed, with a reported total number of 12 340 trials and 10 937 306 participants. Of the corresponding authors 90% were from high-income countries (41% from the UK). Of the 746 reviews in which at least one trial had met the inclusion criteria, only 55% provided a summary of the country of included trials. Analysis of the 633 reviews in which country of trials could be established revealed that almost 90% of trials and over 80% of participants were from high-income countries. 438 (5%) trials including 1 145 013 (11.7%) participants were undertaken in low-middle income countries. We found that only 13 (0.15%) trials with 982 (0.01%) participants were undertaken in low-income countries. Other than the five Cochrane NCD corresponding authors from South Africa, only one other corresponding author was from Africa (Gambia).

DISCUSSION

The overwhelming body of evidence for NCDs pertains to high-income countries, with only a small number of review authors based in low-income settings. As a consequence, there is an urgent need for research infrastructure and funding for the undertaking of high-quality trials in this area.

Multi-criteria analysis towards the new end use of recycled water for household laundry: a case study in Sydney

This paper aims to put forward several management alternatives regarding the application of recycled water for household laundry in Sydney. Based on different recycled water treatment techniques such as microfiltration (MF), granular activated carbon (GAC) or reverse osmosis (RO), and types of washing machines (WMs), five alternatives were proposed as follows: (1) do nothing scenario; (2) MF+existing WMs; (3) MF+new WMs; (4) MF-GAC+existing WMs; and (5) MF-RO+existing WMs. Accordingly, a comprehensive quantitative assessment on the trade-off among a variety of issues (e.g., engineering feasibility, initial cost, energy consumption, supply flexibility and water savings) was performed over the alternatives. This was achieved by a computer-based multi-criteria analysis (MCA) using the rank order weight generation together with preference ranking organization method for enrichment evaluation (PROMETHEE) outranking techniques. Particularly, the generated 10,000 combinations of weights via Monte Carlo simulation were able to significantly reduce the man-made errors of single fixed set of weights because of its objectivity and high efficiency. To illustrate the methodology, a case study on Rouse Hill Development Area (RHDA), Sydney, Australia was carried out afterwards. The study was concluded by highlighting the feasibility of using highly treated recycled water for existing and new washing machines. This could provide a powerful guidance for sustainable water reuse management in the long term. However, more detailed field trials and investigations are still needed to effectively understand, predict and manage the impact of selected recycled water for new end use alternatives.

Variation between countries in the frequency of diabetic ketoacidosis at first presentation of type 1 diabetes in children: a systematic review

AIMS/HYPOTHESIS

Type 1 diabetes is the most frequent endocrine disease in children, with 65,000 children diagnosed worldwide every year. Up to 80% of these children present with diabetic ketoacidosis (DKA), which is associated with both short-term risks and long-term consequences. This study aimed to characterise the worldwide variation in presentation of type 1 diabetes to inform future interventions to reduce this excess morbidity and mortality.

METHODS

This was a systematic review of studies indexed on PubMed, EMBASE, Web of Science, Scopus or CINAHL before March 2011 that included unselected groups of children presenting with new-onset type 1 diabetes, reported the proportion presenting with DKA and used a definition of DKA based on measurement of pH or bicarbonate.

RESULTS

Sixty-five studies of cohorts comprising over 29,000 children in 31 countries were included. The frequency of DKA at diagnosis ranged from 12.8% to 80%, with highest frequencies in the United Arab Emirates, Saudi Arabia and Romania, and the lowest in Sweden, the Slovak Republic and Canada. Multivariable modelling showed the frequency of DKA was inversely associated with gross domestic product, latitude and background incidence of type 1 diabetes.

CONCLUSIONS/INTERPRETATION

This is the first description of the variation in frequency of DKA at presentation of type 1 diabetes in children across countries. It demonstrates large variations that may, at least in part, be explained by different levels of disease awareness and healthcare provision and suggests ways to decrease the excess morbidity and mortality associated with DKA at diagnosis.

The bilayer lipid membrane as a basis for a selective sensor for ammonia

The development of an electrochemical method for the selective sensing of ammonia gas, based on a modified bilayer lipid membrane, is described. Membrane selectivity for ammonium ion is achieved through incorporation of the antibiotic nonactin as ion-carrier. The detection limits compare favourably with those for conventional ammonia gas-sensing electrodes, but the selectivity is much superior. Theoretical evaluation of the potential sensitivity of the new gas-sensor with respect to design parameters is described.

Traumatic wound microbiome workshop

On May 9-10, 2011, the Walter Reed Army Institute of Research, as the Army Center of Excellence for Infectious Disease, assembled over a dozen leaders in areas related to research into the communities of microorganisms which colonize and infect traumatic wounds. The objectives of the workshop were to obtain guidance for government researchers, to spur research community involvement in the field of traumatic wound research informed by a microbiome perspective, and to spark collaborative efforts serving the Wounded Warriors and similarly wounded civilians. During the discussions, it was made clear that the complexity of these infections will only be met by developing a new art of clinical practice that engages the numerous microbes and their ecology. It requires the support of dedicated laboratories and technologists who advance research methods such as community sequencing, as well as the kinds of data analysis expertise and facilities. These strategies already appear to be bearing fruit in the clinical management of chronic wounds. There are now funding announcements and programs supporting this area of research open to extramural collaborators.

Effect of rosiglitazone on capillary density and angiogenesis in adipose tissue of normoglycaemic humans in a randomised controlled trial

AIMS/HYPOTHESIS

Recent reports of decreased capillary density in the adipose tissue of obese individuals suggest that an imbalance of angiogenesis and adipogenesis may, in part, underlie insulin resistance. This study aimed to determine whether the insulin-sensitising peroxisome proliferator-activated receptor γ (PPARγ) activator rosiglitazone affects adipose tissue vascularisation in normal humans.

METHODS

A randomised, parallel-group, investigator-blinded placebo-controlled trial was conducted with normoglycaemic volunteers with BMI 27-43, recruited from the community at the University of Massachusetts Medical School, Worcester, MA, USA. Peri-umbilical adipose tissue biopsies were obtained before and after treatment for 6 weeks with rosiglitazone (8 mg once daily) or placebo, which were randomly allocated from a sequentially numbered list. The primary outcomes were adipocyte size and capillary density measured by immunohistochemistry, and angiogenic potential assessed by capillary sprout formation in Matrigel. Secondary outcomes were serum adiponectin, glycaemic, lipid and liver function variables.

RESULTS

A total of 35 individuals fulfilling the inclusion criteria were randomised, and complete before-vs-after analyses were achieved in 30 participants (13 and 17, placebo and rosiglitazone, respectively). Significant differences, assessed by paired two-tailed Student t tests, were seen in response to rosiglitazone for adipocyte size (3,458 ± 202 vs 2,693 ± 223 μm(2), p = 0.0049), capillary density (5.6 ± 0.5 vs 7.5 ± 0.5 lumens/field, p = 0.0098), serum adiponectin (14.3 ± 1.5 vs 28.6 ± 3.0 ng/ml, p < 0.0001) and alkaline phosphatase (1.04 ± 0.07 vs 0.87 ± 0.05 μkat/l, p = 0.001). A difference in angiogenic potential before and after treatment between the placebo and rosiglitazone groups was also seen (-23.88 ± 14 vs 13.42 ± 13, p = 0.029, two-tailed Mann-Whitney test).

CONCLUSIONS/INTERPRETATION

Significant effects on adipose tissue vascular architecture occur after a short period of treatment with rosiglitazone in individuals with normal glucose tolerance. Improved adipose tissue vascularisation may, in part, mediate the therapeutic actions of this class of drugs.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01150981

FUNDING

The study was funded by National Institutes of Health grant DK089101 to S. Corvera, and by pilot funding from the University of Massachusetts (UMASS) Center for Clinical Translational Sciences (M. Thompson, S. Malkani and S. Corvera). Morphology core services were supported by UMASS Diabetes Endocrine Research Center (DERC) grant DK32520.

Systematic review and validation of prediction rules for identifying children with serious infections in emergency departments and urgent-access primary care

BACKGROUND

Although the vast majority of children with acute infections are managed at home, this is one of the most common problems encountered in children attending emergency departments (EDs) and primary care. Distinguishing children with serious infection from those with minor or self-limiting infection is difficult. This can result in misdiagnosis of children with serious infections, which results in a poorer health outcome, or a tendency to refer or admit children as a precaution; thus, inappropriately utilising secondary-care resources.

OBJECTIVES

We systematically identified clinical features and laboratory tests which identify serious infection in children attending the ED and primary care. We also identified clinical prediction rules and validated those using existing data sets.

DATA SOURCES

We searched MEDLINE, Medion, EMBASE, Cumulative Index to Nursing and Allied Health Literature and Database of Abstracts of Reviews of Effects in October 2008, with an update in June 2009, using search terms that included terms related to five components: serious infections, children, clinical history and examination, laboratory tests and ambulatory care settings. We also searched references of included studies, clinical content experts, and relevant National Institute for Health and Clinical Excellence guidelines to identify relevant studies. There were no language restrictions. Studies were eligible for inclusion if they were based in ambulatory settings in economically developed countries.

REVIEW METHODS

Literature searching, selection and data extraction were carried out by two reviewers. We assessed quality using the quality assessment of diagnostic accuracy studies (QUADAS) instrument, and used spectrum bias and validity of the reference standard as exclusion criteria. We calculated the positive likelihood ratio (LR+) and negative likelihood ratio (LR-) of each feature along with the pre- and post-test probabilities of the outcome. Meta-analysis was performed using the bivariate method when appropriate. We externally validated clinical prediction rules identified from the systematic review using existing data from children attending ED or primary care.

RESULTS

We identified 1939 articles, of which 35 were selected for inclusion in the review. There was only a single study from primary care; all others were performed in the ED. The quality of the included studies was modest. We also identified seven data sets (11,045 children) to use for external validation. The most useful clinical features for ruling in serious infection was parental or clinician overall concern that the illness was different from previous illnesses or that something was wrong. In low- or intermediate-prevalence settings, the presence of fever had some diagnostic value. Additional red flag features included cyanosis, poor peripheral circulation, rapid breathing, crackles on auscultation, diminished breath sounds, meningeal irritation, petechial rash, decreased consciousness and seizures. Procalcitonin (LR+ 1.75-2.96, LR- 0.08-0.35) and C-reactive protein (LR+ 2.53-3.79, LR- 0.25-0.61) were superior to white cell counts. The best performing clinical prediction rule was a five-stage decision tree rule, consisting of the physician's gut feeling, dyspnoea, temperature ≥ 40 °C, diarrhoea and age. It was able to decrease the likelihood of serious infections substantially, but on validation it provided good ruling out value only in low-to-intermediate-prevalence settings (LR- 0.11-0.28). We also identified and validated the Yale Observation Scale and prediction rules for pneumonia, meningitis and gastroenteritis.

LIMITATIONS

Only a single study was identified from primary-care settings, therefore results may lack generalisability.

CONCLUSIONS

Several clinical features are useful to increase or decrease the probability that a child has a serious infection. None is sufficient on its own to substantially raise or lower the risk of serious infection. Some are highly specific ('red flags'), so when present should prompt a more thorough or repeated assessment. C-reactive protein and procalcitonin demonstrate similar diagnostic characteristics and are both superior to white cell counts. However, even in children with a serious infection, red flags will occur infrequently, and their absence does not lower the risk. The diagnostic gap is currently filled by using clinical 'gut feeling' and diagnostic safety-netting, which are still not well defined. Although two prediction rules for serious infection and one for meningitis provided some diagnostic value, we do not recommend widespread implementation at this time. Future research is needed to identify predictors of serious infection in children in primary-care settings, to validate prediction rules more widely, and determine the added value of blood tests in primary-care settings.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Derivation and validation of age and temperature specific reference values and centile charts to predict lower respiratory tract infection in children with fever: prospective observational study

OBJECTIVES

To develop reference values and centile charts for respiratory rate based on age and body temperature, and to determine how well these reference values can predict the presence of lower respiratory tract infections (LRTI) in children with fever.

DESIGN

Prospective observational study.

PARTICIPANTS

Febrile children aged at least 1 month to just under 16 years (derivation population, n = 1555; validation population, n = 671) selected from patients attending paediatric emergency departments or assessment units in hospitals.

SETTING

One hospital in the Netherlands in 2006 and 2008 (derivation population); one hospital in the Netherlands in 2003-05 and one hospital in the United Kingdom in 2005-06 (validation population).

INTERVENTION

We used the derivation population to produce respiratory rate centile charts, and calculated 50th, 75th, 90th, and 97th centiles of respiratory rate at a specific body temperature. Multivariable regression analysis explored associations between respiratory rate, age, and temperature; results were validated in the validation population by calculating diagnostic performance measures, z scores, and corresponding centiles of children with diagnoses of pneumonic LRTI (as confirmed by chest radiograph), non-pneumonic LRTI, and non-LRTI.

MAIN OUTCOME MEASURE

Age, respiratory rate (breaths/min) and body temperature (°C), presence of LRTI.

RESULTS

Respiratory rate increased overall by 2.2 breaths/min per 1°C rise (standard error 0.2) after accounting for age and temperature in the model. We observed no interactions between age, temperature, and respiratory rates. Age and temperature dependent cut-off values at the 97th centile were more useful for ruling in LRTI (specificity 0.94 (95% confidence interval 0.92 to 0.96), positive likelihood ratio 3.66 (2.34 to 5.73)) than existing respiratory rate thresholds such as Advanced Pediatrics Life Support values (0.53 (0.48 to 0.57), 1.59 (1.41 to 1.80)). However, centile cut-offs could not discriminate between pneumonic LRTI and non-pneumonic LRTI.

CONCLUSIONS

Age specific and temperature dependent centile charts describe new reference values for respiratory rate in children with fever. Cut-off values at the 97th centile were more useful in detecting the presence of LRTI than existing respiratory rate thresholds.

Endovascular treatment of acute aortic dissection: indications, techniques and results

Acute aortic dissection is the commonest life-threatening event involving the aorta. Endovascular solutions have revolutionised the treatment of this pathology. This article describes the optimal management of acute dissection, through primary medical management, planning endovascular solutions, technique of stent-graft deployment, adjuncts to endovascular therapy and future developments. It reports the current evidence for improved outcomes with endovascular management and explores the challenges that increasing application of this technology will face.

Complementary Effects of Multivitamin and Omega-3 Fatty Acid Supplementation on Indices of Cardiovascular Health in Individuals with Elevated Homocysteine

Homocysteine (HCY), C-reactive protein (hsCRP), and triglycerides (TG) are risk factors for cardiovascular disease (CVD). While multivitamins (MVit) may reduce HCY and hsCRP, omega-3 fatty acids (N3) reduce TG; yet, they are seldom studied simultaneously. We randomly assigned 100 participants with baseline HCY (> 8.0 umol/L) to the daily ingestion of: (1) placebo, (2) MVit (VitC: 200 mg; VitE: 400 IU; VitB6: 25 mg; Folic Acid: 400 ug; VitB12: 400 ug) + placebo, (3) N3 (2 g N3, 760 mg EPA, 440 mg DHA)+placebo, or (4) MVit + N3 for 12 weeks. At follow-up, we observed significant reductions in HCY (umol/L) for the MVit (- 1.43, 95 %CI, - 2.39, - 0.47) and MVit + N3 groups (- 1.01, 95 %CI, - 1.98, - 0.04) groups, both being significant (p < 0.05) vs. placebo (- 0.57, 95 %CI, - 1.49, 0.35) and N3 (1.11, 95 % CI, 0.07, 2.17). hsCRP (nmol/L) was significantly reduced in the MVit (- 6.00, 95 %CI, - 1.04, - 0.15) and MVit + N3 (- 0.98, 95 %CI, - 1.51, - 0.46) groups, but not vs. placebo (- 0.15, 95 %CI, - 0.74, 0.43) or N3 (- 0.53, 95 %CI, - 1.18, 0.12). Lastly, we observed significant reductions in TG for the N3 (- 0.41, 95 %CI, - 0.69, - 0.13) and MVit + N3 (- 0.71, 95 %CI, - 0.93, - 0.46) groups, both significant vs. placebo (- 0.10, 95 %CI, - 0.36, 0.17) and MVit groups (0.15, 95 %CI, - 12, 0.42). The co-ingestion of MVit + N3 provides synergistic affects on HCY, hsCRP, and plasma TG.

Paradoxical roles of serine racemase and D-serine in the G93A mSOD1 mouse model of amyotrophic lateral sclerosis

D-serine is an endogenous neurotransmitter that binds to the NMDA receptor, thereby increasing the affinity for glutamate, and the potential for excitotoxicity. The primary source of D-serine in vivo is enzymatic racemization by serine racemase (SR). Regulation of D-serine in vivo is poorly understood, but is thought to involve a combination of controlled production, synaptic reuptake by transporters, and intracellular degradation by D-amino acid oxidase (DAO). However, SR itself possesses a well-characterized eliminase activity, which effectively degrades D-serine as well. D-serine is increased two-fold in spinal cords of G93A Cu,Zn-superoxide dismutase (SOD1) mice--the standard model of amyotrophic lateral sclerosis (ALS). ALS mice with SR disruption show earlier symptom onset, but survive longer (progression phase is slowed), in an SR-dependent manner. Paradoxically, administration of D-serine to ALS mice dramatically lowers cord levels of D-serine, leading to changes in the onset and survival very similar to SR deletion. D-serine treatment also increases cord levels of the alanine-serine-cysteine transporter 1 (Asc-1). Although the mechanism by which SOD1 mutations increases D-serine is not known, these results strongly suggest that SR and D-serine are fundamentally involved in both the pre-symptomatic and progression phases of disease, and offer a direct link between mutant SOD1 and a glial-derived toxic mediator.

Which symptoms and clinical features correctly identify serious respiratory infection in children attending a paediatric assessment unit?

OBJECTIVE

Parent-reported symptoms are frequently used to triage children, but little is known about which symptoms identify children with serious respiratory infections. The authors aimed to identify symptoms and triage findings predictive of serious respiratory infection, and to quantify agreement between parent and nurse assessment.

DESIGN

Prospective diagnostic cohort study.

SETTING

Paediatric Assessment Unit, University Hospitals Coventry and Warwickshire NHS Trust.

PATIENTS

535 children aged between 3 months and 12 years with suspected acute infection.

METHODS

Parents completed a symptom questionnaire on arrival. Children were triaged by a nurse, who measured routine vital signs. The final diagnosis at discharge was used as the outcome. Symptoms and triage findings were analysed to identify features diagnostic of serious respiratory infection. Agreement between parent and triage nurse assessment was measured and kappa values calculated.

RESULTS

Parent-reported symptoms were poor indicators of serious respiratory infection (positive likelihood ratio (LR+) 0.56-1.93) and agreed poorly with nurse assessment (kappa 0.22-0.56). The best predictor was clinical assessment of respiratory distress (LR+ 5.04). Oxygen saturations <94% were highly specific (specificity 95.1%) but had poor sensitivity (35.6%). Tachypnoea (defined by current Advanced Paediatric Life Support standards) offered little discriminatory value.

CONCLUSION

Parent-reported symptoms were unreliable discriminators of serious respiratory infection in children with suspected acute infection, and did not correlate well with nurse assessment. Using symptoms to identify higher risk children in this setting is unreliable. Nurse triage assessment of respiratory distress and some vital signs are important predictors.

Medical-device recalls in the UK and the device-regulation process: retrospective review of safety notices and alerts

Background Medical devices are used widely for virtually every disease and condition. Although devices are subject to regulation, the number of recalls, the clinical data requirements for regulation and the impact on patient safety are poorly understood. Methods The authors defined a device using European directives and used publicly available information on the Medicines and Health Regulatory Authority website to determine the number of devices recalled from January 2006 to December 2010. Two reviewers independently assessed Field Safety Notices and Medical Device Alerts. The authors wrote to manufacturers to obtain further information and clinical data, and summarised data by year, Conformité Européenne classification, indication, and Food and Drug Administration recall system of severity. Results In total, 2124 field safety notices were issued over the 5-year period, an increase of 1220% (62 in 2006 to 757 in 2010). 447 Medical Device Alerts were issued in the same period, and 44% were assessed as a reasonable probability of causing serious adverse health consequences or death. The authors wrote to 192 manufacturers of withdrawn devices and received 101 (53%) replies; only four (2.1%) provided the clinical data the authors requested. A lack of available transparent data prevented full analyses of the safety impact. Of the highest-risk recalled devices, more than half were related to the cardiovascular system (25%) or musculoskeletal system (33%), and 88% (95% CI 80% to 97%) were assessed as a reasonable probability of causing serious adverse health consequences or death. For low-risk devices, the figure was 34% (95% CI 26% to 42%). Conclusion The number of medical devices subject to recalls or warnings in the UK has risen dramatically. A substantial number of these devices may have caused serious adverse effects in patients and contributed to healthcare costs. Significant problems exist in the UK with a lack of access to transparent data and a registry of the highest-risk devices.

Paradoxical reactions in non-HIV tuberculosis presenting as endobronchial obstruction

Paradoxical reaction (PR) in tuberculosis (TB) is common and may affect up to 25% of patients. PR has the potential to cause significant morbidity and, on occasion, death. Although PR has been recognised for some time, the pathophysiology, especially in HIV-negative patients, is not well understood. We present two cases of PR in HIV-negative patients with TB presenting as significant airway obstruction secondary to a florid endobronchial component. These cases demonstrate that PR should be considered in all patients presenting with airway symptoms who have started TB treatment. The outcomes of the cases illustrate the need for wider recognition of this condition and more research to characterise patients who may be at risk, in order to gain a greater understanding of the mechanisms involved and to make or predict this diagnosis earlier.

Presumptive Nocardia spp. infection in a dog treated with cyclosporin and ketoconazole

CASE HISTORY

A dog that had received 8 months of cyclosporin and ketoconazole therapy for treatment of atopic dermatitis subsequently developed severe neurological disease, that failed to respond to treatment with trimethoprim-sulphadiazine and clindamycin. HISTOPATHOLOGICAL FINDINGS: Histopathological examination of the pulmonary parenchyma and spinal cord revealed loose aggregates of Gram-positive, partially acid-fast, fine, beaded, filamentous bacteria, most consistent with Nocardia spp.

DIAGNOSIS

A presumptive diagnosis was made of disseminated nocardiosis of the spinal cord and lungs.

CLINICAL RELEVANCE

Nocardia spp. is an opportunistic actinomycete that may cause disseminated disease, particularly in immunocompromised animals. Cyclosporin is used in veterinary medicine to control immune-mediated and allergic disorders, with few reported adverse side effects. This case gives further evidence that involvement of the spinal cord in nocardiosis of the central nervous system (CNS) carries a poor prognosis, and opportunistic infection by Nocardia spp. may be a potential complication of immunosuppressive cyclosporin therapy in the dog.

Predictability of oppositional defiant disorder and symptom dimensions in children and adolescents with ADHD combined type

BACKGROUND

Oppositional defiant disorder (ODD) is frequently co-occurring with attention deficit hyperactivity disorder (ADHD) in children and adolescents. Because ODD is a precursor of later conduct disorder (CD) and affective disorders, early diagnostic identification is warranted. Furthermore, the predictability of three recently confirmed ODD dimensions (ODD-irritable, ODD-headstrong and ODD-hurtful) may assist clinical decision making.

METHOD

Receiver-operating characteristic (ROC) analysis was used in order to test the diagnostic accuracy of the Conners' Parent Rating Scale revised (CPRS-R) and the parent version of the Strength and Difficulties Questionnaire (PSDQ) in the prediction of ODD in a transnational sample of 1093 subjects aged 5-17 years from the International Multicentre ADHD Genetics study. In a second step, the prediction of three ODD dimensions by the same parent rating scales was assessed by backward linear regression analyses.

RESULTS

ROC analyses showed adequate diagnostic accuracy of the CPRS-R and the PSDQ in predicting ODD in this ADHD sample. Furthermore, the three-dimensional structure of ODD was confirmed by confirmatory factor analysis and the CPRS-R emotional lability scale significantly predicted the ODD irritable dimension.

CONCLUSIONS

The PSDQ and the CPRS-R are both suitable screening instruments in the identification of ODD. The emotional lability scale of the CPRS-R is an adequate predictor of irritability in youth referred for ADHD.

Outreach and screening following the 2005 London bombings: usage and outcomes

BACKGROUND

Little is known about how to remedy the unmet mental health needs associated with major terrorist attacks, or what outcomes are achievable with evidence-based treatment. This article reports the usage, diagnoses and outcomes associated with the 2-year Trauma Response Programme (TRP) for those affected by the 2005 London bombings.MethodFollowing a systematic and coordinated programme of outreach, the contact details of 910 people were obtained by the TRP. Of these, 596 completed a screening instrument that included the Trauma Screening Questionnaire (TSQ) and items assessing other negative responses. Those scoring ≥6 on the TSQ, or endorsing other negative responses, received a detailed clinical assessment. Individuals judged to need treatment (n=217) received trauma-focused cognitive-behaviour therapy (TF-CBT) or eye movement desensitization and reprocessing (EMDR). Symptom levels were assessed pre- and post-treatment with validated self-report measures of post-traumatic stress disorder (PTSD) and depression, and 66 were followed up at 1 year.

RESULTS

Case finding relied primarily on outreach rather than standard referral pathways such as primary care. The effect sizes achieved for treatment of DSM-IV PTSD exceeded those usually found in randomized controlled trials (RCTs) and gains were well maintained an average of 1 year later.

CONCLUSIONS

Outreach with screening, linked to the provision of evidence-based treatment, seems to be a viable method of identifying and meeting mental health needs following a terrorist attack. Given the failure of normal care pathways, it is a potentially important approach that merits further evaluation.