Small bowel obstruction caused by a fibrotic bow-string appendix: a consequence of non-operative management of acute appendicitis

A 73-year-old woman presented with small bowel obstruction that failed to settle with conservative management. Over the previous 2 years she had presented twice with computed tomography scan-proven acute appendicitis with localised perforation of the appendix tip. In view of medical comorbidities, she was treated non-operatively with clinical and radiological resolution on each occasion, but on the third presentation laparoscopy was undertaken for non-resolving small bowel obstruction and the non-inflamed appendix itself was identified as a fibrous band causing compression of the distal ileum and complete small bowel obstruction. Following division and appendicectomy, the patient made an uneventful recovery. This case illustrates the potential consequence of repeated appendiceal inflammation and non-operative management and may be seen increasingly as this approach is widely adopted during the COVID-19 pandemic.

982 Embolisation of Iatrogenic Lumbar Artery Bleed Causing Psoas Haematoma Following Elective Lumbar Puncture

The case of a 59-year-old female patient presenting as a surgical emergency with abdominal pain and a positive Obraztsova's sign. Seven days prior to the presentation, she had attended her General Practice (GP) complaining of sudden onset severe occipital headache associated with photophobia, vertigo, and paraesthesia. Due to a family history of cerebral aneurysms, her GP urgently transferred her to an emergency department, where she was subsequently admitted under the acute medical team. A lumbar puncture (LP) had been performed to exclude a subarachnoid haemorrhage. The patient was investigated with a Computerised Tomography abdomen and pelvis with contrast and was subsequently found to have an acute lumbar arterial bleed causing haemodynamic instability and a psoas haematoma. An emergency lumbar artery embolisation procedure was performed by the interventional radiology department in order to stabilise the bleed. The patient made a full recovery prior to discharge. This rare case exemplifies the value of obtaining adequate history in arriving at a diagnosis. In the appropriate clinical context, a contrast-enhanced CT scan of the abdomen and pelvis should be obtained to exclude this treatable condition. Also, measures to minimize the risk of complications and make lumbar puncture safer should be incorporated into guidelines, including methods to ensure that the correct position of L3/L4 or L4/L5 is found prior to performing the procedure, use of atraumatic spinal needles and performing the procedure under ultrasound guidance.

Long-term outcomes of real world 'watch and wait' data for rectal cancer after neoadjuvant chemoradiotherapy

AIM

A 'watch and wait' (W&W) strategy after neoadjuvant long-course chemoradiotherapy (NACRT) remains controversial. Whilst encouraging short-term data exist, the strategy will be judged on long-term data. We present long-term, real-world UK data from a single National Health Service trust.

METHODS

An analysis was performed of a prospectively maintained W&W database over 9 years between 2010 and 2018. Outcome measures include incidence and time to regrowth and overall and disease-free survival.

RESULTS

We diagnosed 563 rectal cancers in 9 years. In all, 283 patients underwent rectal resection (50.3%). NACRT was used in 155 patients for margin-threatened tumours on staging MRI. Forty-nine patients (31.6%) experienced either a 'near complete' or a complete clinical response (cCR) at their 10 weeks post-NACRT assessment (MRI and endoscopy). The median age was 69 years (range 44-83), and the male to female ratio was 32:17. The median follow-up was 38 months (range 12-96). The median tumour distance from the anal verge was 7 cm (1-15 cm). Twenty-two patients had a cCR on initial assessment and 27 patients had a 'near' cCR. Of those 27 who experienced a 'near' cCR, 17 (63%) progressed to cCR on repeat assessment and 10 (37%) did not. Of these 10 patients, seven underwent standard surgical resection and three were unfit for surgery. R0 for the seven with delayed resection was 100%. Of 39 patients (22 cCR and 17 'near' cCR who progressed to cCR) (25.2% of those receiving NACRT), six patients experienced local regrowth (15.4%). The median time to local regrowth was 29 months (15-60 months). One of these six patients underwent salvage abdominoperineal resection, one was advised to have contact radiotherapy and four opted against surgery and also had contact radiotherapy. The overall survival was 100% at 2 years and 90% at 5 years. Disease-free survival was 90.47% at 2 years and 74.8% at 5 years.

CONCLUSION

A W&W treatment strategy was employed safely in this patient cohort with acceptable rates of local regrowth and survival.

Biochemical and anaplerotic applications of in vitro models of propionic acidemia and methylmalonic acidemia using patient-derived primary hepatocytes

Propionic acidemia (PA) and methylmalonic acidemia (MMA) are autosomal recessive disorders of propionyl-CoA (P-CoA) catabolism, which are caused by a deficiency in the enzyme propionyl-CoA carboxylase or the enzyme methylmalonyl-CoA (MM-CoA) mutase, respectively. The functional consequence of PA or MMA is the inability to catabolize P-CoA to MM-CoA or MM-CoA to succinyl-CoA, resulting in the accumulation of P-CoA and other metabolic intermediates, such as propionylcarnitine (C3), 3-hydroxypropionic acid, methylcitric acid (MCA), and methylmalonic acid (only in MMA). P-CoA and its metabolic intermediates, at high concentrations found in PA and MMA, inhibit enzymes in the first steps of the urea cycle as well as enzymes in the tricarboxylic acid (TCA) cycle, causing a reduction in mitochondrial energy production. We previously showed that metabolic defects of PA could be recapitulated using PA patient-derived primary hepatocytes in a novel organotypic system. Here, we sought to investigate whether treatment of normal human primary hepatocytes with propionate would recapitulate some of the biochemical features of PA and MMA in the same platform. We found that high levels of propionate resulted in high levels of intracellular P-CoA in normal hepatocytes. Analysis of TCA cycle intermediates by GC-MS/MS indicated that propionate may inhibit enzymes of the TCA cycle as shown in PA, but is also incorporated in the TCA cycle, which does not occur in PA. To better recapitulate the disease phenotype, we obtained hepatocytes derived from livers of PA and MMA patients. We characterized the PA and MMA donors by measuring key proximal biomarkers, including P-CoA, MM-CoA, as well as clinical biomarkers propionylcarnitine-to-acetylcarnitine ratios (C3/C2), MCA, and methylmalonic acid. Additionally, we used isotopically-labeled amino acids to investigate the contribution of relevant amino acids to production of P-CoA in models of metabolic stability or acute metabolic crisis. As observed clinically, we demonstrated that the isoleucine and valine catabolism pathways are the greatest sources of P-CoA in PA and MMA donor cells and that each donor showed differential sensitivity to isoleucine and valine. We also studied the effects of disodium citrate, an anaplerotic therapy, which resulted in a significant increase in the absolute concentration of TCA cycle intermediates, which is in agreement with the benefit observed clinically. Our human cell-based PA and MMA disease models can inform preclinical drug discovery and development where mouse models of these diseases are inaccurate, particularly in well-described species differences in branched-chain amino acid catabolism.

Identifying risk factors for perinatal death at Tororo District Hospital, Uganda: a case-control study

Background

Sub-Saharan Africa faces a disproportionate burden of perinatal deaths globally. However, data to inform targeted interventions on an institutional level is lacking, especially in rural settings. The objective of this study is to identify risk factors for perinatal death at a resource-limited hospital in Uganda.

Methods

This is a retrospective case-control study at a district hospital in eastern Uganda using birth registry data. Cases were admissions with stillbirths at or beyond 24 weeks or neonatal deaths within 28 days of birth. Controls were admissions that resulted in deliveries immediately preceding and following each case. We compared demographic and obstetric factors between cases and controls to identify risk factors for perinatal death. Subgroup analysis of type of perinatal death was also performed. Chi square, Fisher’s exact, t-test, and Wilcoxon-Mann-Whitney rank sum tests were utilized for bivariate analysis, and multiple logistic regression for multivariate analysis.

Results

From January 2014 to December 2014, there were 185 cases of perinatal death, of which 36% (n = 69) were macerated stillbirths, 40% (n = 76) were fresh stillbirths, and 25% (n = 47) were neonatal deaths. The rate of perinatal death among all deliveries at the institution was 35.5 per 1000 deliveries. Factors associated with increased odds perinatal death included: prematurity (adjusted odds ratio (aOR) 19.7, 95% confidence interval (CI) 7.2–49.2), breech presentation (aOR 7.0, CI 1.4–35.5), multiple gestation (aOR 4.0, CI 1.1–13.9), cesarean delivery (aOR 3.8, CI 2.3–6.4) and low birth weight (aOR 2.5, CI 1.1–5.3). Analysis by subtype of perinatal death revealed distinct associations with the aforementioned risk factors, in particular for antepartum hemorrhage, which was only associated with fresh stillbirths (aOR 6.7, CI 1.6–28.8), and low birth weight.

Conclusions

The rate of perinatal death at our rural hospital site was higher than national targets, and these deaths were associated with prematurity, low birth weight, breech presentation, multiple gestation, and cesarean delivery. This data and the approach utilized to acquire it can be leveraged to inform targeted interventions to reduce the rate of stillbirths and neonatal deaths in similar low resource settings.

Toxigenic Clostridium difficile carriage in general practice: results of a laboratory-based cohort study

OBJECTIVES

Reported rates of community-acquired Clostridium difficile infections (CDIs) have been increasing. However, the true burden of the disease in general practice is unknown in France. Our objective was to determine the incidence of toxigenic C. difficile carriage and the percentage of stool samples prescribed by general practitioners (GPs) which contained free C. difficile toxins.

METHODS

During an 11-month period, all stool samples submitted for any enteric pathogen detection to 15 different private laboratories in Paris and the surrounding areas were tested for C. difficile, irrespective of the GPs' request. A clinical questionnaire was completed for each patient. Stool samples were screened using a rapid simultaneous glutamate dehydrogenase and toxins A/B detection test: any positive result (glutamate dehydrogenase or toxin) was further confirmed by the stool cytotoxicity assay (CTA) on MRC-5 cells and by toxigenic culture (TC) at a central laboratory. The C. difficile isolates were characterized by PCR ribotyping.

RESULTS

A total of 2541 patients (1295 female, 1246 male) were included. The incidences of patients with a positive toxigenic culture and a positive CTA were 3.27% (95% CI 2.61%-4.03%) and 1.81% (95% CI 1.33%-2.41%), respectively. GPs requested C. difficile testing in only 12.93% of the stool samples, detecting 52.30% of all TC-positive patients. The 83 toxigenic C. difficile strains belonged to 36 different PCR ribotypes.

CONCLUSIONS

Toxigenic C. difficile carriage is frequent in general practice but remains under-recognized. It may affect young patients without previous antimicrobial therapy or hospitalization.

Storage Levels of Ddt Metabolites in Mouse Tissues following Long Term Exposure to Technical DDT

The storage levels of DDT and its metabolites, following the long term administration of technical DDT at the dose levels of 2, 20, 50 and 250 ppm to mice, were evaluated in the fat tissue, liver, kidney, brain and reproductive organs. In addition, storage levels were evaluated in foetuses and newborns of DDT-treated mothers. Apart from op'-DDT, there was a direct relationship between the concentration of each metabolite in each organ and the dose to which the animal was exposed. The highest concentration of DDT and metabolites was found in the fat tissue followed by reproductive organs, liver and kidney together, and lastly brain. The most prevalent metabolite was pp'-DDT, except in the liver, where pp'-DDD showed the highest concentration. Pregnant females had lower concentrations of all metabolites than non-pregnant females. The concentration of residues in samples of total foetal litters was directly related to the concentration of DDT fed to the mother. There was a strong negative correlation between the concentration of pp'-DDT and that of pp'-DDD in the foetuses and the placentas of the same litter. A significant increase in whole body DDT concentration was observed shortly after birth.

Membrane lipid order of sub-synaptic T cell vesicles correlates with their dynamics and function

During an immune response, T cells survey antigen presenting cells for antigenic peptides via the formation of an interface known as an immunological synapse. Among the complex and dynamic biophysical phenomena occurring at this interface is the trafficking of sub-synaptic vesicles carrying a variety of proximal signalling molecules. Here, we show that rather than being a homogeneous population, these vesicles display a diversity of membrane lipid order profiles, as measured using the environmentally sensitive dye di-4-ANEPPDHQ and multi-spectral TIRF microscopy. Using live-cell imaging, vesicle tracking and a variety of small molecule drugs to manipulate components of the actin and tubulin cytoskeleton, we show that the membrane lipid order of these vesicles correlate with their dynamics. Furthermore, we show that the key proximal signalling molecule Linker for Activation of T cells (LAT) is enriched in specific vesicle populations as defined by their higher membrane order. These results imply that vesicle lipid order may represent a novel regulatory mechanism for the sorting and trafficking of signalling molecules at the immunological synapse, and, potentially, other cellular structures.

Community-wide Prevalence of Malaria Parasitemia in HIV-Infected and Uninfected Populations in a High-Transmission Setting in Uganda

BACKGROUND

Malaria control strategies depend on identifying individuals with parasitemia, who may be asymptomatic but retain the ability to transmit disease. Population-level survey data on parasitemia are limited and traditionally exclude adults and human immunodeficiency virus (HIV)-infected individuals.

METHODS

We performed a cross-sectional survey of residents aged 18 months to 94 years in Nankoma, Uganda. Blood specimens were collected using the dried blood spot technique from 9629 residents (87.6%), and samples from a subset of 4131 were tested for malaria parasites, using loop-mediated isothermal amplification. Population-level prevalence was estimated using a weighted proportion, and predictors of parasitemia were identified using a multivariate Poisson regression model.

RESULTS

The community prevalence of parasitemia was 83.8% (95% confidence interval [CI], 82.9%-84.6%). Parasite prevalence was highest among children aged 5-14 years (94.7%) and lowest among adults (61.9%). In analysis that controlled for age, HIV-infected individuals with an undetectable viral load had a lower risk of parasitemia, compared with HIV-uninfected individuals (adjusted relative risk, 0.16; 95% CI, .10-.27; P < .001).

CONCLUSIONS

In a rural Ugandan community, 2 years after distribution of long-lasting insecticide-treated bed nets, the prevalence of malaria parasitemia was high across all ages, peaking in school-aged children. Persons with well-controlled HIV infection had a lower risk of parasitemia, presumably reflecting access to HIV care.

Rectal mucocoele following subtotal colectomy for colitis

We present a unique case of a rectal mucocoele affecting a patient several years after his subtotal colectomy for ulcerative colitis. This was secondary to both a benign anorectal stenosis and a benign mucus secreting rectal adenoma. This case highlights the importance of surveillance in such patients.

Abstract 133: Hemodynamic Environment-dependent Effects of Human HDL and oxHDL on Vessel Wall Inflammation

High density lipoprotein (HDL) concentration is inversely correlated with cardiovascular disease and exerts atheroprotective effects on endothelial (EC) and smooth muscle cells (SMC). Oxidation of LDL (oxLDL) is a well-appreciated driver of atherosclerosis. What is less well known is that HDL can become oxidized (oxHDL) by myeloperoxidase, which may negate its beneficial effects. Further, previous mechanistic studies of HDL were performed on static culture ECs or SMCs that do not take into consideration in vivo hemodynamics; a critical regulator of vascular phenotype. Regional hemodynamics prime EC/SMCs towards either an atheroprotective phenotype or, in regions such as bifurcations, towards an atheroprone, pro-inflammatory phenotype. We assessed the role of the hemodynamic environment in modulating the differential response of vascular cells to human HDL or oxHDL from normal donors. To test this, HDL was added to EC/SMC cocultures primed by atheroprotective or atheroprone shear stresses derived from the human carotid bifurcation or an “Advanced Inflammatory” condition that combines atheroprone shear stress with additional atherogenic factors such as oxLDL and TNFα. In the presence of HDL, ECs under Advanced Inflammatory conditions reduced pro-inflammatory (NFkB Activity, IL6, COX2), and oxidative stress (SOD2), but did not have an effect in baseline atheroprotective and atheroprone conditions. Many of the anti-inflammatory responses of endothelial cells were retained when HDL was oxidized. Conversely, while HDL had minimal effect on SMC gene expression, oxHDL was found to reduced the atheroprotective phenotype by potently inducing oxidative and inflammatory cytokine genes/secreted proteins (IL1B, IL6). Overall, this study illustrates the importance of reproducing relevant in vivo environments in order to understand HDL-mediated mechanisms in vascular biology in vitro. This study supports that oxidation dysfunctionally transforms HDL from an atheroprotective to an inflammatory and intrinsically oxidative particle and might damage otherwise healthy regions of the vasculature. Thus, measurement of circulating HDL without consideration of HDL composition and oxidation may limit its predictive value for cardiovascular risk.

Abstract 73: Atrial Fibrillation-induced Changes in Left Atrial Hemodynamics Directly Impact the Thrombotic Potential of Human Primary Endothelial Cell Cultures

Thrombus formation in the left atrial appendage (LAA) of the heart is a source of stroke risk in patients with atrial fibrillation (Afib). Strategies to prevent thromboembolism from the LAA via restoration of normal rhythm or prevention of clot formation are limited by lack of adequate human surrogate systems that recapitulate the biology ex vivo. Endothelial cell phenotype and function in blood vessels and chambers of the heart are regulated in part by regional hemodynamics. Blood flow shear forces in the LAA are substantially altered during Afib. Thus, we hypothesized that Afib-induced alterations in hemodynamics directly impacts the thrombotic potential of the endothelium in the LAA. To test this, human primary aortic endothelial cell cultures were primed under hemodynamic shear forces simulating the human LAA during normal sinus rhythm for 24 hrs and continued under sinus rhythm or switched to simulate Afib for an additional 24 hrs. Compared to sustained sinus rhythm, Afib hemodynamics suppressed genes (qRTPCR) that define a healthy/quiescent endothelial cell phenotype (e.g. KLF2 and NOS3/eNOS) while inducing the pro-thrombotic gene F3 (tissue factor) and suppressing ADAMSTS13, MMP14 and TIMP2. To determine whether the observed molecular response produced a functional prothrombotic phenotype, hemodynamic primed aortic endothelial cells were exposed to dilute (~27% final concentration) human platelet-free plasma supplemented with Alexa488-labeled human fibrinogen, corn trypsin inhibitor and calcium. Cleavage of fibrinogen to fibrin and concomitant deposition on the endothelium was measured by quantitative confocal microscopy. When exposed to Afib hemodynamics, endothelial cells supported significant fibrin deposition that extended to greater depth (i.e., thicker) on the endothelium compared to sinus rhythm hemodynamics. In conclusion, we show for the first time a direct mechanistic link between changes in LAA hemodynamics associated with development of Afib and functional alterations in the thrombotic potential of the endothelium. This study produced a novel insight enabled by studying potential triggers of thrombosis in a context that more closely mimics the normal and pathological human in vivo environment.

Abstract 310: GLP-1 Cleavage Product (9-36)-NH2 Exerts Pro-survival Effects on Smooth Muscle Cells in Advanced Inflammatory Hemodynamic Conditions

Glucagon-like peptide-1(GLP-1), an incretin hormone, has been shown to have atheroprotective effects on the cardiovascular system in animal models of atherosclerosis and diabetes, and in several clinical trials. These beneficial effects are presumed to occur through active GLP-1 (7-36)-NH2/(7-37), and its receptor GLP-1R; however, within minutes GLP-1 (7-36)-NH2/(7-37) becomes cleaved and inactivated by DPP4 into its smaller metabolite, GLP-1 (9-36)-NH2(9-37). It still remains unclear how GLP-1 (7-36)-NH2/(7-37), its metabolites, and GLP-1R provide beneficial vascular effects. We sought to elucidate the role of GLP-1 on vessel wall health using a novel in vitro human surrogate system that cocultures human endothelial (EC) and smooth muscle cells (SMCs) and applies human hemodynamics from the carotid bifurcation, a site prone to developing atherosclerosis, combined with other atherogenic factors (oxidized LDL, TNFα). Though, we found GLP-1R to be highly expressed in ECs and SMCs from both healthy and advanced inflammatory vascular environments, atheroprotective effects from the addition of GLP-1 (7-36)-NH2 or (9-36)-NH2 acted primarily on SMCs. In SMCs from atherogenic hemodynamic conditions, GLP-1 (7-36)-NH2 reduced NFkB activity and increased the anti-oxidant response protein, HO-1, via GLP-1R. A novel finding was that the cleaved metabolite, GLP-1 (9-36)-NH2, elicited the same response. Though GLP-1 (9-36)-NH2 did not alter downstream inflammatory gene expression, the NFkB-dependent pathways converged on pro-survival signaling since the metabolite GLP-1 (9-36)-NH2 uniquely decreased apoptotic signaling, including cleaved Caspase-3. These same responses were not seen with cleavage-resistant forms of GLP-1 (7-36)-NH2, but were rescued by adding back the cleavage product, (9-36)-NH2_further illustrating the distinct role of GLP-1 (9-36)-NH2 in promoting cell survival. This suggests future therapeutics would benefit by combining native GLP-1 along with its cleavage product, GLP-1 (9-36)-NH2. These findings demonstrate the novel effect of native GLP-1 and its cleavage-products on vessel wall health and provide new insights into creating more effective GLP-1 therapeutics for treatment of atherosclerosis and diabetes.

Oseltamivir and inhaled zanamivir as influenza prophylaxis in Thai health workers: a randomized, double-blind, placebo-controlled safety trial over 16 weeks

OBJECTIVES

Long-term chemoprophylaxis using neuraminidase inhibitors may be needed during influenza epidemics but safety data are limited to several weeks. We sought to assess the tolerability of oseltamivir and zanamivir as primary prophylaxis over 16 weeks.

METHODS

We conducted a parallel group, double blind, 2 (active drug) :1 (placebo) randomized trial of oral oseltamivir/placebo or inhaled zanamivir/placebo over 16 weeks in healthy, Thai hospital professionals at two Bangkok hospitals. The primary endpoint was study withdrawal due to drug-related (possibly, probably, definitely) serious or adverse events (AEs) graded ≥ 2.

RESULTS

Recruited subjects numbered 129 oseltamivir/65 placebo and 131 zanamivir/65 placebo. A total of 102 grade ≥ 2 AEs were reported or detected in 69 subjects: 23/129 (17.8%) versus 15/65 (23.1%) (P=0.26), and 23/131 (17.6%) versus 8/65 (12.3%) (P=0.28). Intercurrent infections/fevers [26/102 (25.5%)], abnormal biochemistry [25/102 (24.5%)] and gastrointestinal symptoms [18/102 (17.6%)] were the most frequently reported AEs. There were no drug-related study withdrawals. Eight serious AEs were all due to intercurrent illnesses. Laboratory, lung function and ECG parameters were similar between drugs and placebos.

CONCLUSIONS

Oseltamivir and zanamivir were well tolerated in healthy hospital professionals. Both drugs can be recommended for primary influenza prophylaxis for up to 16 weeks.

Phamerator: a bioinformatic tool for comparative bacteriophage genomics

BACKGROUND

Bacteriophage genomes have mosaic architectures and are replete with small open reading frames of unknown function, presenting challenges in their annotation, comparative analysis, and representation.

RESULTS

We describe here a bioinformatic tool, Phamerator, that assorts protein-coding genes into phamilies of related sequences using pairwise comparisons to generate a database of gene relationships. This database is used to generate genome maps of multiple phages that incorporate nucleotide and amino acid sequence relationships, as well as genes containing conserved domains. Phamerator also generates phamily circle representations of gene phamilies, facilitating analysis of the different evolutionary histories of individual genes that migrate through phage populations by horizontal genetic exchange.

CONCLUSIONS

Phamerator represents a useful tool for comparative genomic analysis and comparative representations of bacteriophage genomes.

Drowning associated pneumonia: a descriptive cohort

PURPOSE

Pneumonia is the most common infectious complication of drowning. Pneumonia is potentially life threatening and should be treated by effective antibiotic therapy. However the risk factors, microbiological causes, diagnostic approach and appropriate therapy for pneumonia associated with drowning are not well described. The microbiological ecology of the body of water where immersion occurred could be of import. The aim of this study was to report on microorganisms involved in pneumonia associated with drowning and out of hospital cardiac arrest after successful cardiopulmonary resuscitation. Additionally, we retrieved and undertook microbiological analysis on samples of water from our local river.

METHODS

This retrospective study included all patients having suffered an out of hospital cardiac arrest due to drowning and admitted to our tertiary care academic hospital between 2002 and 2010. Data concerning bacteriological lung samples (tracheal aspirate or bronchoalveolar lavage) at admission were reported and compared to bacteriological samples obtained from our local river (the river Seine).

RESULTS

A total of thirty-seven patients were included in the study. Lung samples were obtained for twenty-one of these patients. Lung samples were positive in nineteen cases, with a high frequency of multi-drug resistant bacteria. Samples from the Seine River found microorganisms similar to those found in drowning associated pneumonia.

CONCLUSIONS

Drowning associated pneumonia can be due to multi drug resistant bacteria. When treating drowning associated pneumonia, antibiotics should be effective against bacteria similar to those found in the body of water where immersion occurred.

Do clinicians consider the results of the BinaxNOW Streptococcus pneumoniae urinary antigen test when adapting antibiotic regimens for pneumonia patients?

The BinaxNOW Streptococcus pneumoniae urinary antigen test is a rapid and reliable immunochromatographic test (ICT) for the identification of a pneumococcal aetiology of pneumonia. The aim of this study was to evaluate the attitude of clinicians in their everyday practice towards prescription of the ICT and the impact of its results on the adaptation of the antibiotic therapy when pneumonia is suspected. From October 2007 to March 2008, we prospectively evaluated 541 consecutive inpatients for whom the ICT was performed in our institution. Of the 541 patients evaluated, only 233 (43%) were suspected by the treating physicians to have a pneumonia, 58 of whom had a positive ICT result. Among these 58 patients, four (7%) and 26 (45%), respectively, were treated with amoxycillin monotherapy before and after the ICT result had been obtained (p <10(-4)). Although a positive ICT result led to a rise in the proportion of patients treated with amoxycillin alone, a large number continued to be treated with broader-spectrum antibiotics. These results suggest that prescription monitoring of the ICT should be implemented along with encouragement to adhere more strictly to treatment guidelines.

Corynebacterium jeikeium pacemaker infection associated with antineutrophil cytoplasmic antibodies: a single positive blood culture could be sufficient for diagnosis

Corynebacterium jeikeium, a member of the non-diphtheria corynebacteria, has been rarely reported as being responsible for cardiovascular-device infection. Here, we report what is believed to be the first case of C. jeikeium pacemaker infection associated with the presence of proteinase-3 antineutrophil cytoplasmic antibodies. The diagnosis was established based on the positivity of a single positive blood culture and led to pacemaker extraction. This observation highlights the difficulty in the diagnosis of cardiac-device infection in the presence of a single positive blood culture with a fastidious microorganism that could be considered as a contaminant. It also underscores the need for device extraction to ensure healing.

Trajectories of alcohol consumption following liver transplantation

Any use of alcohol in the years following liver transplantation (LTX) approaches 50% of patients transplanted for alcoholic liver disease (ALD). We collected detailed prospective data on alcohol consumption following LTX for ALD to investigate ongoing patterns of use. Using trajectory modeling we identified four distinct alcohol use trajectories. One group had minimal use over time. Two other groups developed early onset moderate-to-heavy consumption and one group developed late onset moderate use. These trajectories demonstrate that alcohol use varies based on timing of onset, quantity and duration. Using discriminant function analysis, we examine characteristics of recipient's pre-LTX alcohol histories and early post-LTX psychological stressors to identify the profile of those at risk for these specific trajectories. We discuss the relevance of these findings to clinical care and preliminarily to outcomes.

[Bacteriological study of ethmoid specimens from patients with nasal polyposis after ethmoidal surgery]

OBJECTIVE

To compare the bacteriological and clinical findings in ethmoid specimens from patients with nasal polyposis after radical ethmoidal surgery.

PATIENTS AND METHODS

From June to November 2008, 60 patients were prospectively included. For each patient, two samples for each ethmoidal cavity were taken. Aerobic and anaerobic bacterial cultures and fungal cultures were processed and the antibiotic susceptibility was evaluated for each isolated bacterial strain.

RESULTS

Pathogenic bacteria were isolated in 48 patients (80%) including predominantly Staphylococcus aureus (60%) or a Gram-negative bacterium. The microorganisms were nearly all susceptible to antibiotics, including the aminoglycosides. No correlation between the presence of pathogenic bacteria and the clinical status of the patients was found.

CONCLUSION

In this study, a great number of patients was colonized with pathogenic bacteria. However, the presence of pathogenic bacteria was not correlated with the clinical status of the patients.

Complex physiological traits as biomarkers of the sub-lethal toxicological effects of pollutant exposure in fishes

Complex physiological traits, such as routine aerobic metabolic rate or exercise performance, are indicators of the functional integrity of fish that can reveal sub-lethal toxicological effects of aquatic pollutants. These traits have proved valuable in laboratory investigations of the sub-lethal effects of heavy metals, ammonia and various xenobiotics. It is not known, however, whether they can also function as biomarkers of the complex potential range of effects upon overall functional integrity caused by exposure to mixtures of chemicals in polluted natural environments. The current study used portable swimming respirometers to compare exercise performance and respiratory metabolism of fish exposed in cages for three weeks to either clean or polluted sites on three urban European river systems: the river Lambro, Milan, Italy; the rivers Blythe, Cole and Tame, Birmingham, UK; and the river Amstel, Amsterdam, The Netherlands. The UK and Italian rivers were variously polluted with high levels of both bioavailable heavy metals and organics, and the Amstel by mixtures of bioavailable organics at high concentrations. In both the UK and Italy, indigenous chub (Leuciscus cephalus) exposed to clean or polluted sites swam equally well in an initial performance test, but the chub from polluted sites could not repeat this performance after a brief recovery interval. These animals were unable to raise the metabolic rate and allocate oxygen towards exercise in the second trial, an effect confirmed in successive campaigns in Italy. Swimming performance was therefore a biomarker indicator of pollutant exposure in chub exposed at these sites. Exposure to polluted sites on the river Amstel did not affect the repeat swimming performance of cultured cloned carp (Cyprinus carpio), indicating either a species-specific tolerance or relative absence of heavy metals. However, measurements of oxygen uptake during swimming revealed increased rates of routine aerobic metabolism in both chub and carp at polluted sites in all of the rivers studied, indicating a sub-lethal metabolic loading effect. Therefore, the physiological traits of exercise performance and metabolic rate have potential as biomarkers of the overall sub-lethal toxic effects of exposure to complex mixtures of pollutants in rivers, and may also provide insight into why fish do not colonize some polluted environments.

Positive replication and linkage disequilibrium mapping of the chromosome 21q22.1 malaria susceptibility locus

Four cytokine receptor genes are located on Chr21q22.11, encoding the alpha and beta subunits of the interferon-alpha receptor (IFNAR1 and IFNAR2), the beta subunit of the interleukin 10 receptor (IL10RB) and the second subunit of the interferon-gamma receptor (IFNGR2). We previously reported that two variants in IFNAR1 were associated with susceptibility to malaria in Gambians. We now present an extensive fine-scale mapping of the associated region utilizing 45 additional genetic markers obtained from public databases and by sequencing a 44 kb region in and around the IFNAR1 gene in 24 Gambian children (12 cases/12 controls). Within the IFNAR1 gene, a newly studied C --> G single-nucleotide polymorphism (IFNAR1 272354c-g) at position -576 relative to the transcription start was found to be more strongly associated with susceptibility to severe malaria. Association was observed in three populations: in Gambian (P=0.002), Kenyan (P=0.022) and Vietnamese (P=0.005) case-control studies. When all three studies were combined, using the Mantel-Haenszel test, the presence of IFNAR1 -576G was associated with a substantially elevated risk of severe malaria (N=2444, OR=1.38, 95% CI: 1.17-1.64; P=1.7 x 10(-4)). This study builds on previous work to further highlight the importance of the type-I interferon pathway in malaria susceptibility and illustrates the utility of typing SNPs within regions of high linkage disequilibrium in multiple populations to confirm initial positive associations.

Identification and analysis of functional elements in 1% of the human genome by the ENCODE pilot project

We report the generation and analysis of functional data from multiple, diverse experiments performed on a targeted 1% of the human genome as part of the pilot phase of the ENCODE Project. These data have been further integrated and augmented by a number of evolutionary and computational analyses. Together, our results advance the collective knowledge about human genome function in several major areas. First, our studies provide convincing evidence that the genome is pervasively transcribed, such that the majority of its bases can be found in primary transcripts, including non-protein-coding transcripts, and those that extensively overlap one another. Second, systematic examination of transcriptional regulation has yielded new understanding about transcription start sites, including their relationship to specific regulatory sequences and features of chromatin accessibility and histone modification. Third, a more sophisticated view of chromatin structure has emerged, including its inter-relationship with DNA replication and transcriptional regulation. Finally, integration of these new sources of information, in particular with respect to mammalian evolution based on inter- and intra-species sequence comparisons, has yielded new mechanistic and evolutionary insights concerning the functional landscape of the human genome. Together, these studies are defining a path for pursuit of a more comprehensive characterization of human genome function.

Identification of higher-order functional domains in the human ENCODE regions

It has long been posited that human and other large genomes are organized into higher-order (i.e., greater than gene-sized) functional domains. We hypothesized that diverse experimental data types generated by The ENCODE Project Consortium could be combined to delineate active and quiescent or repressed functional domains and thereby illuminate the higher-order functional architecture of the genome. To address this, we coupled wavelet analysis with hidden Markov models for unbiased discovery of "domain-level" behavior in high-resolution functional genomic data, including activating and repressive histone modifications, RNA output, and DNA replication timing. We find that higher-order patterns in these data types are largely concordant and may be analyzed collectively in the context of HeLa cells to delineate 53 active and 62 repressed functional domains within the ENCODE regions. Active domains comprise approximately 44% of the ENCODE regions but contain approximately 75%-80% of annotated genes, transcripts, and CpG islands. Repressed domains are enriched in certain classes of repetitive elements and, surprisingly, in evolutionarily conserved nonexonic sequences. The functional domain structure of the ENCODE regions appears to be largely stable across different cell types. Taken together, our results suggest that higher-order functional domains represent a fundamental organizing principle of human genome architecture.

Unsupervised segmentation of continuous genomic data

The advent of high-density, high-volume genomic data has created the need for tools to summarize large datasets at multiple scales. HMMSeg is a command-line utility for the scale-specific segmentation of continuous genomic data using hidden Markov models (HMMs). Scale specificity is achieved by an optional wavelet-based smoothing operation. HMMSeg is capable of handling multiple datasets simultaneously, rendering it ideal for integrative analysis of expression, phylogenetic and functional genomic data.

AVAILABILITY

http://noble.gs.washington.edu/proj/hmmseg

In vitro-clinical correlations for amphotericin B susceptibility in AIDS-associated cryptococcal meningitis

Reliable measures of antifungal drug susceptibility are needed. We tested the susceptibility of Cryptococcus neoformans from patients treated with amphotericin B. In vitro susceptibility employed a modified broth macrodilution method. We demonstrate a strong correlation between the quantitative measures of in vitro amphotericin B susceptibility and the quantitative response observed in patients.

Development and validation of a bioanalytical method using automated solid-phase extraction and LC-UV for the simultaneous determination of lumefantrine and its desbutyl metabolite in plasma

A bioanalytical method for the determination of lumefantrine (LF) and its metabolite desbutyl-lumefantrine (DLF) in plasma by solid-phase extraction (SPE) and liquid chromatography has been developed. Plasma proteins were precipitated with acetonitrile:acetic acid (99:1, v/v) containing a DLF analogue internal standard before being loaded onto a octylsilica (3 M Empore) SPE column. Two different DLF analogues were evaluated as internal standards. The compounds were analysed by liquid chromatography UV detection on a SB-CN (250 mm x 4.6 mm) column with a mobile phase containing acetonitrile-sodium phosphate buffer pH (2.0; 0.1 M) (55:45, v/v) and sodium perchlorate 0.05 M. Different SPE columns were evaluated during method development to optimise reproducibility and recovery for LF, DLF and the two different DLF analogues. The within-day precisions for LF were 6.6 and 2.1% at 0.042 and 8.02 microg/mL, respectively, and for DLF 4.5 and 1.5% at 0.039 and 0.777 microg/mL, respectively. The between-day precisions for LF were 12.0 and 2.9% at 0.042 and 8.02 microg/mL, respectively, while for DLF 0.7 and 1.2% at 0.039 and 0.777 microg/mL, respectively. The limit of quantification was 0.024 and 0.021 microg/mL for LF and DLF, respectively. Different amounts of lipids in plasma did not affect the absolute recovery of LF or DLF.

The effects of acclimation to reversed seasonal temperatures on the swimming performance of adult brown trout Salmo trutta

Adult brown trout (Salmo trutta) were acclimatised to and maintained at seasonal temperatures (5 degrees C in winter; 15 degrees C in summer) and acclimated to reversed seasonal temperatures (15 degrees C in winter; 5 degrees C in summer) while exposed to the natural (i.e. seasonally variable) photoperiod. The mean critical swimming speeds (U(crit)) of animals acclimatised to the seasonal temperatures were similar, but more than 30% greater than those for fish acclimated to the reversed seasonal temperatures. The lower values of U(crit) that accompanied acclimation to reversed seasonal temperatures appeared largely to result from the inability of white muscle to function maximally, since the concentrations of lactate and ammonia in white muscle of fish swum to U(crit) at reversed seasonal temperatures were significantly lower than those in fish swum at seasonal temperatures. These observations, together with biochemical and morphometric attributes of muscle tissue, suggest that swimming ability is influenced, at least in part, by seasonal factors other than temperature. These data have important implications for the design of experiments using fish that experience predictable, usually seasonal, changes in their natural environment (temperature, dissolved oxygen, changes in water levels, etc.).

Minor physical anomalies are not increased in the offspring of mothers with systemic lupus erythematosus

OBJECTIVE

To determine the incidence and type of minor physical anomalies (MPAs) in infants born to mothers with systemic lupus erythematosus (SLE).

METHODS

Each trimester, pregnant women with SLE were assessed for disease activity, prescribed drug use, and exposure to tobacco, alcohol, and illicit drugs through a self reported questionnaire. Infant examinations were performed on 30/39 (77%) live births in women with SLE and the incidence of MPAs determined.

RESULTS

2/30 (7%) patients had three or more MPAs; 4 (13%) had two; 7 (23%) had one; and 17 (57%) had none. One in three women reported alcohol, tobacco, and illicit drug use. Facial anomalies were the most common MPAs. The relative risk and 95% confidence interval for any MPA were 2.05 (0.99 to 4.26) for tobacco use; 1.95 (0.92 to 4.11) for alcohol use; 1.36 (0.165 to 11.23) for maternal disease flare; 0.63 (0.27 to 1.47) for prednisone use; and 0.72 (0.21 to 2.44) for aspirin use.

CONCLUSION

13/30 (43%) infants had minor anomalies-a similar incidence to that of the general population. Counselling for preventable self reported exposure is advisable in addition to counselling specifically for lupus management during pregnancy.

Area deprivation predicts lung function independently of education and social class

The cross-sectional association between socioeconomic status (at both the individual and area-based level) and lung function, as measured by forced expiratory volume in one second, in a large population-based cohort was investigated. The study population consisted of 22,675 males and females aged 39-79 yrs. They were recruited from the general community in Norfolk, UK using general practice age/sex registers, as part of the European Prospective Investigation into Cancer (EPIC-Norfolk). It was found that being in a manual occupational social class, having no educational qualifications and living in a deprived area all independently predicted significantly lower lung function, even after controlling for smoking habit. The influence of area-deprivation on lung function, independent of individual socioeconomic status and of individual smoking habit, suggests that apart from targeting individuals who are at high-risk, such as smokers, environmental determinants also need to be examined when considering measures to improve respiratory health.

Vitamin C and the risk of developing inflammatory polyarthritis: prospective nested case-control study

OBJECTIVE

To investigate whether, there is an association between consumption of fruit and vegetables and dietary antioxidants and the risk of developing inflammatory polyarthritis (IP).

METHODS

In a prospective, population based, nested case-control study of residents of Norfolk, UK, men and women aged 45-74 years were recruited, between 1993 and 1997 through general practice age-sex registers to the Norfolk arm of the European Prospective Investigation of Cancer (EPIC-Norfolk). Dietary intake was assessed at baseline using 7 day diet diaries. Seventy three participants who went on to develop IP between 1993 and 2001 and were registered by the Norfolk Arthritis Register (NOAR) were identified. Incident cases of IP, assessed by general practitioners, fulfilled the criteria of two or more swollen joints, persisting for a minimum of 4 weeks. Each case of IP was matched for age and sex with two controls free of IP.

RESULTS

Lower intakes of fruit and vegetables, and vitamin C were associated with an increased risk of developing IP. Those in the lowest category of vitamin C intake, compared with the highest, increased their risk of developing IP more than threefold, adjusted odds ratio (OR) with 95% confidence intervals (CI) 3.3 (95% CI 1.4 to 7.9). Weak inverse associations between vitamin E and beta-carotene intake and IP risk were found.

CONCLUSION

Patients with IP (cases) consumed less fruit and vitamin C than matched controls, which appeared to increase their risk of developing IP. The mechanism for this effect is uncertain. Thus similar studies are necessary to confirm these results.

Abdominal obesity and respiratory function in men and women in the EPIC-Norfolk Study, United Kingdom

Poor respiratory function and obesity are associated with all-cause and cardiovascular disease mortality. Obese persons may also have impaired lung function, but the mechanism is unclear. The authors investigated the relation between abdominal pattern of obesity and respiratory function in the European Prospective Investigation into Cancer and Nutrition-Norfolk (EPIC-Norfolk) cohort in Norfolk, United Kingdom. This analysis included 9,674 men and 11,876 women aged 45-79 years with no known preexisting serious illness who had complete anthropometric and respiratory function measures obtained at a health visit between 1993 and 1997. Waist:hip ratio was used to assess abdominal obesity, and forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC), obtained by spirometry, were used to assess respiratory function. Both FEV1 and FVC were linearly and inversely related across the entire range of waist:hip ratio in both men and women. This relation persisted after adjustment for age, body mass index, cigarette smoking, social class, physical activity index, prevalent bronchitis/emphysema, and prevalent asthma. The association remained significant among nonobese nonsmokers without preexisting respiratory disease. In the general adult population, abdominal fat deposition may play a role in the impairment of respiratory function among the abdominally obese.

Occupational social class, educational level and area deprivation independently predict plasma ascorbic acid concentration: a cross-sectional population based study in the Norfolk cohort of the European Prospective Investigation into Cancer (EPIC-Norfolk)

OBJECTIVE

To investigate the independent association between three different measures of socioeconomic status and plasma ascorbic acid level.

DESIGN

Cross-sectional population based study.

SETTING AND PARTICIPANTS

20 292 men and women aged 39-79 y who participated in the EPIC-Norfolk study.

RESULTS

Individuals in manual social classes, who had no educational qualifications or those who lived in the most deprived areas had significantly lower levels of plasma ascorbic acid compared to those in nonmanual social classes, with at least O-level qualifications or who lived in less deprived areas. The magnitude of effect for each measure of socioeconomic status was greater in current smokers compared to current nonsmokers.

CONCLUSION

Education and social class were stronger predictors of differences in ascorbic acid levels, an indicator of dietary health behaviour, than a deprivation index based on the Townsend score. This suggests that education could be particularly important in influencing large socioeconomic differentials in health related behaviours and potentially, health outcomes in the UK.