AIM: To examine factors influencing percutaneous endoscopic gastrostomy (PEG) uptake and outcomes in motor neuron disease (MND) in a tertiary care centre.
METHODS: Case notes from all patients with a confirmed diagnosis of MND who had attended the clinic at the Repatriation General Hospital between January 2007 and January 2011 and who had since died, were audited. Data were extracted for demographics (age and gender), disease characteristics (date of onset, bulbar or peripheral predominance, complications), date and nature of discussion of gastrostomy insertion, nutritional status [weight measurements, body mass index (BMI)], date of gastrostomy insertion and subsequent progress (duration of survival) and quality of life (QoL) [Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R)]. In addition, the type of clinician initiating the discussion regarding gastrostomy was recorded as Nutritional Support Team (involved in providing nutrition input viz Gastroenterologist, Speech Pathologist, Dietitian) and other (involved in non-nutritional aspects of patient care). Factors affecting placement and outcomes including length of survival, change in weight and QoL were determined.
RESULTS: Case records were available for all 86 patients (49 men, mean age at diagnosis 66.4 years). Thirty-eight patients had bulbar symptoms and 48 had peripheral disease as their presenting feature. Sixty-six patients reported dysphagia. Thirty-one patients had undergone gastrostomy insertion. The major indications for PEG placement were dysphagia and weight loss. Nine patients required immediate full feeding, whereas 17 patients initially used the gastrostomy to supplement oral intake, 4 for medication administration and 1 for hydration. Initially the PEG regime met 73% ± 31% of the estimated total energy requirements, increasing to 87% ± 32% prior to death. There was stabilization of weight in patients undergoing gastrostomy [BMI at 3 mo (22.6 ± 2.2 kg/m2) and 6 mo (22.5 ± 2.0 kg/m2) after PEG placement compared to weight at the time of the procedure (22.5 ± 3.0 kg/m2)]. However, weight loss recurred in the terminal stages of the illness. There was a strong trend for longer survival from diagnosis among MND in PEG recipients with limb onset presentation compared to similar patients who did not undergo the procedure (P = 0.063). Initial discussions regarding PEG insertion occurred earlier after diagnosis when seen by nutrition support team (NST) clinicians compared to other clinicians. (5.4 ± 7.0 mo vs 11.9 ± 13.4 mo, P = 0.028). There was a significant increase in PEG uptake (56% vs 24%, P = 0.011) if PEG discussions were initiated by the NST staff compared to other clinicians. There was no change in the ALSFRS-R score in patients who underwent PEG (pre 34.1 ± 8.6 vs post 34.8 ± 7.4), although in non-PEG recipients there was a non-significant fall in this score (33.7 ± 7.9 vs 31.6 ± 8.8). Four patients died within one month of the procedure, 4 developed bacterial site infection requiring antibiotics and 1 required endoscopic therapy for gastric bleeding. Less serious complications attributed to the procedure included persistent gastrostomy site discomfort, poor appetite, altered bowel function and bloating.
CONCLUSION: Initial discussion with NST clinicians increases PEG uptake in MND. Gastrostomy stabilizes patient weight but weight loss recurs with advancing disease.
Motor neuron disease; Multidisciplinary management; Nutrition support team; Percutaneous endoscopic gastrostomy; Survival
Mosquito-borne alphaviruses such as chikungunya virus and Ross River virus (RRV) are emerging pathogens capable of causing large-scale epidemics of virus-induced arthritis and myositis. The pathology of RRV-induced disease in both humans and mice is associated with induction of the host inflammatory response within the muscle and joints, and prior studies have demonstrated that the host complement system contributes to development of disease. In this study, we have used a mouse model of RRV-induced disease to identify and characterize which complement activation pathways mediate disease progression after infection, and we have identified the mannose binding lectin (MBL) pathway, but not the classical or alternative complement activation pathways, as essential for development of RRV-induced disease. MBL deposition was enhanced in RRV infected muscle tissue from wild type mice and RRV infected MBL deficient mice exhibited reduced disease, tissue damage, and complement deposition compared to wild-type mice. In contrast, mice deficient for key components of the classical or alternative complement activation pathways still developed severe RRV-induced disease. Further characterization of MBL deficient mice demonstrated that similar to C3−/− mice, viral replication and inflammatory cell recruitment were equivalent to wild type animals, suggesting that RRV-mediated induction of complement dependent immune pathology is largely MBL dependent. Consistent with these findings, human patients diagnosed with RRV disease had elevated serum MBL levels compared to healthy controls, and MBL levels in the serum and synovial fluid correlated with severity of disease. These findings demonstrate a role for MBL in promoting RRV-induced disease in both mice and humans and suggest that the MBL pathway of complement activation may be an effective target for therapeutic intervention for humans suffering from RRV-induced arthritis and myositis.
Arthritogenic alphaviruses such as Ross River virus (RRV) and chikungunya virus are transmitted to humans by mosquitoes and cause epidemics of debilitating infectious arthritis and myositis in various areas around the world. Studies in humans and mice indicate that the host inflammatory response is critical for development of RRV-induced arthritis and myositis, and the host complement system, a component of the host inflammatory response, plays an essential role in the development of RRV-induced disease through activation of complement receptor 3 (CR3)-bearing inflammatory cells. Of the three main complement activation pathways, only the lectin pathway activated by mannose binding lectin (MBL) was essential for RRV-induced complement activation, tissue destruction, and disease. Furthermore, we found that levels of MBL were elevated in human patients suffering from RRV-induced polyarthritis and MBL levels correlated with disease severity. Taken together, our data implicates a role for MBL in mediating RRV-induced disease in both humans and mice, and suggests that therapeutic targeting of MBL may be an effective strategy for disease treatment in humans.
MAVIDOS is a randomised, double-blind, placebo-controlled trial (ISRCTN82927713, registered 2008 Apr 11), funded by Arthritis Research UK, MRC, Bupa Foundation and NIHR.
Osteoporosis is a major public health problem as a result of associated fragility fractures. Skeletal strength increases from birth to a peak in early adulthood. This peak predicts osteoporosis risk in later life. Vitamin D insufficiency in pregnancy is common (31% in a recent Southampton cohort) and predicts reduced bone mass in the offspring. In this study we aim to test whether offspring of mothers supplemented with vitamin D in pregnancy have higher bone mass at birth than those whose mothers were not supplemented.
Women have their vitamin D status assessed after ultrasound scanning in the twelfth week of pregnancy at 3 trial centres (Southampton, Sheffield, Oxford). Women with circulating 25(OH)-vitamin D levels 25-100 nmol/l are randomised in a double-blind design to either oral vitamin D supplement (1000 IU cholecalciferol/day, n = 477) or placebo at 14 weeks (n = 477). Questionnaire data include parity, sunlight exposure, dietary information, and cigarette and alcohol consumption. At 19 and 34 weeks maternal anthropometry is assessed and blood samples taken to measure 25(OH)-vitamin D, PTH and biochemistry. At delivery venous umbilical cord blood is collected, together with umbilical cord and placental tissue. The babies undergo DXA assessment of bone mass within the first 14 days after birth, with the primary outcome being whole body bone mineral content adjusted for gestational age and age. Children are then followed up with yearly assessment of health, diet, physical activity and anthropometric measures, with repeat assessment of bone mass by DXA at age 4 years.
As far as we are aware, this randomised trial is one of the first ever tests of the early life origins hypothesis in human participants and has the potential to inform public health policy regarding vitamin D supplementation in pregnancy. It will also provide a valuable resource in which to study the influence of maternal vitamin D status on other childhood outcomes such as glucose tolerance, blood pressure, cardiovascular function, IQ and immunology.
Vitamin D; cholecalciferol; supplementation; trial; osteoporosis; DXA; pregnancy; neonate
AIM: To characterize the effects of age on the mechanisms underlying the common condition of esophageal dysphagia in older patients, using detailed manometric analysis.
METHODS: A retrospective case-control audit was performed on 19 patients aged ≥ 80 years (mean age 85 ± 0.7 year) who underwent a manometric study for dysphagia (2004-2009). Data were compared with 19 younger dysphagic patients (32 ± 1.7 years). Detailed manometric analysis performed prospectively included basal lower esophageal sphincter pressure (BLESP), pre-swallow and nadir LESP, esophageal body pressures and peristaltic duration, during water swallows (5 mL) in right lateral (RL) and upright (UR) postures and with solids. Data are mean ± SE; a P-value < 0.05 was considered significant.
RESULTS: Elderly dysphagic patients had higher BLESP than younger patients (23.4 ± 3.8 vs 14.9 ± 1.2 mmHg; P < 0.05). Pre-swallow LESP was elevated in the elderly in both postures (RL: 1 and 4 s P = 0.019 and P = 0.05; UR: P < 0.05 and P = 0.05) and solids (P < 0.01). In older patients, LES nadir pressure was higher with liquids (RL: 2.3 ± 0.6 mmHg vs 0.7 ± 0.6 mmHg, P < 0.05; UR: 3.5 ± 0.9 mmHg vs 1.6 ± 0.5 mmHg, P = 0.01) with shorter relaxation after solids (7.9 ± 1.5 s vs 9.7 ± 0.4 s, P = 0.05). No age-related differences were seen in esophageal body pressures or peristalsis duration.
CONCLUSION: Basal LES pressure is elevated and swallow-induced relaxation impaired in elderly dysphagic patients. Its contribution to dysphagia and the effects of healthy ageing require further investigation.
Dysphagia; Elderly; Esophageal Motility; Lower Esophageal Sphincter; Aging
Glucagon-like peptide-1 (GLP-1) attenuates the glycaemic response to small intestinal nutrient infusion in stress-induced hyperglycaemia and reduces fasting glucose concentrations in critically ill patients with type-2 diabetes. The objective of this study was to evaluate the effects of acute administration of GLP-1 on the glycaemic response to small intestinal nutrient infusion in critically ill patients with pre-existing type-2 diabetes.
Eleven critically ill mechanically-ventilated patients with known type-2 diabetes received intravenous infusions of GLP-1 (1.2 pmol/kg/minute) and placebo from t = 0 to 270 minutes on separate days in randomised double-blind fashion. Between t = 30 to 270 minutes a liquid nutrient was infused intraduodenally at a rate of 1 kcal/min via a naso-enteric catheter. Blood glucose, serum insulin and C-peptide, and plasma glucagon were measured. Data are mean ± SEM.
GLP-1 attenuated the overall glycaemic response to nutrient (blood glucose AUC30-270 min: GLP-1 2,244 ± 184 vs. placebo 2,679 ± 233 mmol/l/minute; P = 0.02). Blood glucose was maintained at < 10 mmol/l in 6/11 patients when receiving GLP-1 and 4/11 with placebo. GLP-1 increased serum insulin at 270 minutes (GLP-1: 23.4 ± 6.7 vs. placebo: 16.4 ± 5.5 mU/l; P < 0.05), but had no effect on the change in plasma glucagon.
Exogenous GLP-1 in a dose of 1.2 pmol/kg/minute attenuates the glycaemic response to small intestinal nutrient in critically ill patients with type-2 diabetes. Given the modest magnitude of the reduction in glycaemia the effects of GLP-1 at higher doses and/or when administered in combination with insulin, warrant evaluation in this group.
Proximal femoral fractures are associated with increased morbidity and mortality. Pre-existing malnutrition and weight loss amongst this patient group is of primary concern, with conventional nutrition support being largely ineffective. The inflammatory response post proximal femoral fracture surgery and the subsequent risk of cachexia may explain the inability of conventional high energy high protein management to produce an anabolic response amongst these patients. Omega-3 fatty acids derived from fish oils have been extensively studied for their anti-inflammatory benefits. Due to their anti-inflammatory properties, the benefit of fish oil combined with individualized nutrition support amongst proximal femoral fracture patients post surgery is an attractive potential therapeutic strategy. The aim of the ATLANTIC trial is to assess the potential benefits of an anti-inflammatory dose of fish oil within the context of a 12 week individualised nutrition program, commencing seven days post proximal femoral fracture surgery.
This randomized controlled, double blinded trial, will recruit 150 community dwelling elderly patients aged ≥65 years, within seven days of surgery for proximal femoral fracture. Participants will be randomly allocated to receive either a 12 week individualized nutrition support program complemented with 20 ml/day anti-inflammatory dose fish oil (~3.6 g eicosapentaenoic acid, ~2.4 g docosahexanoic acid; intervention), or, a 12 week individualized nutrition support program complemented with 20 ml/day low dose fish oil (~0.36 g eicosapentaenoic acid, ~0.24 g docosahexanoic acid; control).
The ATLANTIC trial is the first of its kind to provide fish oil combined with individualized nutrition therapy as an intervention to address the inflammatory response experienced post proximal femoral fracture surgery amongst elderly patients. The final outcomes of this trial will assist clinicians in the development of effective and alternative treatment methods post proximal femoral fracture surgery which may ultimately result in a reduction in systemic inflammation, loss of weight and lean muscle and improvements in nutritional status, mobility, independence and quality of life among elderly patients.
In health, hormones secreted from the gastrointestinal tract have an important role in regulating gastrointestinal motility, glucose metabolism and immune function. Recent studies in the critically ill have established that the secretion of a number of these hormones is abnormal, which probably contributes to disordered gastrointestinal and metabolic function. Furthermore, manipulation of endogenous secretion, physiological replacement and supra-physiological treatment (pharmacological dosing) of these hormones are likely to be novel therapeutic targets in this group. Fasting ghrelin concentrations are reduced in the early phase of critical illness, and exogenous ghrelin is a potential therapy that could be used to accelerate gastric emptying and/or stimulate appetite. Motilin agonists, such as erythromycin, are effective gastrokinetic drugs in the critically ill. Cholecystokinin and peptide YY concentrations are elevated in both the fasting and postprandial states, and are likely to contribute to slow gastric emptying. Accordingly, there is a rationale for the therapeutic use of their antagonists. So-called incretin therapies (glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide) warrant evaluation in the management of hyperglycaemia in the critically ill. Exogenous glucagon-like peptide-2 (or its analogues) may be a potential therapy because of its intestinotropic properties.
AIM: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance signals.
METHODS: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the pattern of proximal jejunal fluid bolus movement over a 14 cm-segment. Each subject was given 34 boluses of normal saline (volume from 1 to 30 mL) via the feeding tube placed immediately above the proximal margin of the studied segment. A bolus-induced impedance event occurred if there was > 12% impedance drop from baseline, over ≥ 3 consecutive segments within 10 s of bolus injection. A minor or major impedance event was defined as a duration of impedance drop < 60 s or ≥ 60 s, respectively.
RESULTS: The minimum volume required for a detectable SI impedance event was 2 mL. A direct linear relationship between the SI bolus volume and the occurrence of impedance events was noted until SI bolus volume reached 10 mL, a volume which always produced an impedance flow event. There was a moderate correlation between the bolus volume and the duration of impedance drop (r = 0.63, P < 0.0001) and the number of propagated channels (r = 0.50, P < 0.0001). High volume boluses were associated with more major impedance events (≥ 10 mL boluses = 63%, 3 mL boluses = 17%, and < 3 mL boluses = 0%, P = 0.02).
CONCLUSION: Bolus volume had an impact on the type and length of propagation of SI impedance events and a threshold of 2 mL is required to produce an event.
Bolus volume; Health; Impedance; Luminal flow; Small intestine
The objective of this study was to assess the impact of a landmark annular lesion model on our understanding of the etiopathogenesis of IVD degeneration and to appraise current IVD repairative strategies. A number of studies have utilised the Osti sheep model since its development in 1990. The experimental questions posed at that time are covered in this review, as are significant recent advances in annular repair strategies. The ovine model has provided important spatial and temporal insights into the longitudinal development of annular lesions and how they impact on other discal and paradiscal components such as the NP, cartilaginous end plates, zygapophyseal joints and vertebral bone and blood vessels. Important recent advances have been made in biomatrix design for IVD repair and in the oriented and dynamic culture of annular fibrochondrocytes into planar, spatially relevant, annular type structures. The development of hyaluronan hydrogels capable of rapid in situ gelation offer the possibility of supplementation of matrices with cells and other biomimetics and represent a significant advance in biopolymer design. New generation biological glues and self-curing acrylic formulations which may be augmented with slow delivery biomimetics in microcarriers may also find application in the non-surgical repair of annular defects. Despite major advances, significant technical challenges still have to be overcome before the biological repair of this intractable connective tissue becomes a realistic alternative to conventional surgical intervention for the treatment of chronic degenerate IVDs.
Annular injury; Annular remodelling/repair; Intervertebral disc degeneration; Intervertebral disc repair; Rim lesions; Perlecan
Delayed gastric emptying occurs frequently in critically ill patients and has the potential to adversely affect both the rate, and extent, of nutrient absorption. However, there is limited information about nutrient absorption in the critically ill, and the relationship between gastric emptying (GE) and absorption has hitherto not been evaluated. The aim of this study was to quantify glucose absorption and the relationships between GE, glucose absorption and glycaemia in critically ill patients.
Studies were performed in nineteen mechanically-ventilated critically ill patients and compared to nineteen healthy subjects. Following 4 hours fasting, 100 ml of Ensure, 2 g 3-O-methyl glucose (3-OMG) and 99mTc sulphur colloid were infused into the stomach over 5 minutes. Glucose absorption (plasma 3-OMG), blood glucose levels and GE (scintigraphy) were measured over four hours. Data are mean ± SEM. A P-value < 0.05 was considered significant.
Absorption of 3-OMG was markedly reduced in patients (AUC240: 26.2 ± 18.4 vs. 66.6 ± 16.8; P < 0.001; peak: 0.17 ± 0.12 vs. 0.37 ± 0.098 mMol/l; P < 0.001; time to peak; 151 ± 84 vs. 89 ± 33 minutes; P = 0.007); and both the baseline (8.0 ± 2.1 vs. 5.6 ± 0.23 mMol/l; P < 0.001) and peak (10.0 ± 2.2 vs. 7.7 ± 0.2 mMol/l; P < 0.001) blood glucose levels were higher in patients; compared to healthy subjects. In patients; 3-OMG absorption was directly related to GE (AUC240; r = -0.77 to -0.87; P < 0.001; peak concentrations; r = -0.75 to -0.81; P = 0.001; time to peak; r = 0.89-0.94; P < 0.001); but when GE was normal (percent retention240 < 10%; n = 9) absorption was still impaired. GE was inversely related to baseline blood glucose, such that elevated levels were associated with slower GE (ret 60, 180 and 240 minutes: r > 0.51; P < 0.05).
In critically ill patients; (i) the rate and extent of glucose absorption are markedly reduced; (ii) GE is a major determinant of the rate of absorption, but does not fully account for the extent of impaired absorption; (iii) blood glucose concentration could be one of a number of factors affecting GE.
Hyperglycaemia occurs frequently in the critically ill, affects outcome adversely, and is exacerbated by enteral feeding. Furthermore, treatment with insulin in this group is frequently complicated by hypoglycaemia. In healthy patients and those with type 2 diabetes, exogenous glucagon-like peptide-1 (GLP-1) decreases blood glucose by suppressing glucagon, stimulating insulin and slowing gastric emptying. Because the former effects are glucose-dependent, the use of GLP-1 is not associated with hypoglycaemia. The objective of this study was to establish if exogenous GLP-1 attenuates the glycaemic response to enteral nutrition in patients with critical illness induced hyperglycaemia.
Seven mechanically ventilated critically ill patients, not previously known to have diabetes, received two intravenous infusions of GLP-1 (1.2 pmol/kg/min) and placebo (4% albumin) over 270 minutes. Infusions were administered on consecutive days in a randomised, double-blind fashion. On both days a mixed nutrient liquid was infused, via a post-pyloric feeding catheter, at a rate of 1.5 kcal/min between 30 and 270 minutes. Blood glucose and plasma GLP-1, insulin and glucagon concentrations were measured.
In all patients, exogenous GLP-1 infusion reduced the overall glycaemic response during enteral nutrient stimulation (AUC30–270 min GLP-1 (2077 ± 144 mmol/l min) vs placebo (2568 ± 208 mmol/l min); P = 0.02) and the peak blood glucose (GLP-1 (10.1 ± 0.7 mmol/l) vs placebo (12.7 ± 1.0 mmol/l); P < 0.01). The insulin/glucose ratio at 270 minutes was increased with GLP-1 infusion (GLP-1 (9.1 ± 2.7) vs. placebo (5.8 ± 1.8); P = 0.02) but there was no difference in absolute insulin concentrations. There was a transient, non-sustained, reduction in plasma glucagon concentrations during GLP-1 infusion (t = 30 minutes GLP-1 (90 ± 12 pmol/ml) vs. placebo (104 ± 10 pmol/ml); P < 0.01).
Acute, exogenous GLP-1 infusion markedly attenuates the glycaemic response to enteral nutrition in the critically ill. These observations suggest that GLP-1 and/or its analogues have the potential to manage hyperglycaemia in the critically ill.
Australian New Zealand Clinical Trials Registry number: ACTRN12609000093280.
Using a highly sensitive quantitative RT-PCR method for the measurement of CYP11B1 (11β-hydroxylase) and CYP11B2 (aldosterone synthase) mRNAs, we previously demonstrated that CYP11B2 expression in the central nervous system (CNS) is subject to regulation by dietary sodium. We have now quantified the expression of these genes in the CNS of male Wistar Kyoto (WKY) rats in response to systemic ACTH infusion, dexamethasone infusion, and to adrenalectomy. CYP11B1 and CYP11B2 mRNA levels were measured in total RNA isolated from the adrenal gland and discrete brain regions using real-time quantitative RT-PCR. ACTH infusion (40 ng/day for 7 days, N=8) significantly increased CYP11B1 mRNA in the adrenal gland, hypothalamus, and cerebral cortex compared with animals infused with vehicle only. ACTH infusion decreased adrenal CYP11B2 expression but increased expression in all of the CNS regions except the cortex. Dexamethasone (10 μg/day for 7 days, N=8) reduced adrenal CYP11B1 mRNA compared with control animals but had no significant effect on either gene's expression in the CNS. Adrenalectomy (N=6 per group) significantly increased CYP11B1 expression in the hippocampus and hypothalamus and raised CYP11B2 expression in the cerebellum relative to sham-operated animals. This study confirms the transcription of CYP11B1 and CYP11B2 throughout the CNS and demonstrates that gene transcription is subject to differential regulation by ACTH and circulating corticosteroid levels.
Cholecystokinin (CCK) and peptide YY (PYY) are released in response to intestinal nutrients and play an important physiological role in regulation of gastric emptying (GE). Plasma CCK and PYY concentrations are elevated in critically ill patients, particularly in those with a history of feed intolerance. This study aimed to evaluate the relationship between CCK and PYY concentrations and GE in critical illness.
GE of 100 mL of Ensure® meal (106 kcal, 21% fat) was measured using a 13C-octanoate breath test in 39 mechanically ventilated, critically ill patients (24 males; 55.8 ± 2.7 years old). Breath samples for 13CO2 levels were collected over the course of 4 hours, and the GE coefficient (GEC) (normal = 3.2 to 3.8) was calculated. Measurements of plasma CCK, PYY, and glucose concentrations were obtained immediately before and at 60 and 120 minutes after administration of Ensure.
GE was delayed in 64% (25/39) of the patients. Baseline plasma CCK (8.5 ± 1.0 versus 6.1 ± 0.4 pmol/L; P = 0.045) and PYY (22.8 ± 2.2 versus 15.6 ± 1.3 pmol/L; P = 0.03) concentrations were higher in patients with delayed GE and were inversely correlated with GEC (CCK: r = -0.33, P = 0.04, and PYY: r = -0.36, P = 0.02). After gastric Ensure, while both plasma CCK (P = 0.03) and PYY (P = 0.02) concentrations were higher in patients with delayed GE, there was a direct relationship between the rise in plasma CCK (r = 0.40, P = 0.01) and PYY (r = 0.42, P < 0.01) from baseline at 60 minutes after the meal and the GEC.
In critical illness, there is a complex interaction between plasma CCK, PYY, and GE. Whilst plasma CCK and PYY correlated moderately with impaired GE, the pathogenetic role of these gut hormones in delayed GE requires further evaluation with specific antagonists.
Arthritogenic alphaviruses, including Ross River virus (RRV) and chikungunya virus, are mosquito-borne viruses that cause significant human disease worldwide, including explosive epidemics that can result in thousands to millions of infected individuals. Similar to infection of humans, infection of C57BL/6 mice with RRV results in severe monocytic inflammation of bone, joint, and skeletal muscle tissues. We demonstrate here that the complement system, an important component of the innate immune response, enhances the severity of RRV-induced disease in mice. Complement activation products were detected in the inflamed tissues and in the serum of RRV-infected wild-type mice. Furthermore, mice deficient in C3 (C3−/−), the central component of the complement system, developed much less severe disease signs than did wild-type mice. Complement-mediated chemotaxis is essential for many inflammatory arthritides; however, RRV-infected wild-type and C3−/− mice had similar numbers and composition of inflammatory infiltrates within hind limb skeletal muscle tissue. Despite similar inflammatory infiltrates, RRV-infected C3−/− mice exhibited far less severe destruction of skeletal muscle tissue. In addition to these studies, complement activation was also detected in synovial fluid from RRV-infected patients. Taken together, these findings indicate that complement activation occurs in the tissues of humans and mice infected with RRV and suggest that complement plays an essential role in the effector phase, but not the inductive phase, of RRV-induced arthritis and myositis.
Infection can occur after any spinal procedure that violates the disc and although it is not common, the potential consequences are serious. Treatment of discitis is not always successful and the key to management is prevention. Intradiscal prophylaxis with antibiotic is routinely used in spinal surgery, but there is a limited understanding of how well antibiotics can enter the avascular disc after intravenous injection. An in vivo ovine study to optimise prophylactic and parenteral treatment of discitis is described to assess the effectiveness of cephazolin in preventing and treating infection. The concentration of cephazolin was measured in disc tissue from normal and degenerate sheep discs to determine if cephazolin can enter the disc and if disc degeneration affects antibiotic uptake. Fourteen sheep were deliberately inoculated with bacteria to induce discitis. Eight sheep (“prophylaxis” group) were given either a 0, 1, 2 or 3 g dose of prophylactic cephazolin before inoculation while the remaining sheep (“treatment” group) were treated with cephazolin commencing 7 days after inoculation for 21 days at a dose of 50 mg/kg/day. Histopathology and radiography were used to assess the effect of the different treatments. Cephazolin was given 30 min prior to sacrifice and the intradiscal concentration was measured by biochemistry. In the “prophylaxis” group all doses of antibiotic provided some protection against infection, although it was not dose dependent. In the “treatment” group discitis was confirmed radiologically and histologically in all animals from 2 weeks onwards. Biochemical assay confirmed that antibiotic is distributed throughout the disc but was present in higher concentration in the anulus fibrosus than the nucleus pulposus. This study demonstrated that whilst the incidence of iatrogenic discitis can be reduced by antibiotic prophylaxis, it could not be abolished in all incidences with a broad-spectrum antibiotic such as cephazolin. Furthermore, antibiotics were ineffective at preventing endplate destruction once an intradiscal inoculum was established.
Cephazolin; Discitis; Prophylaxis; Treatment; Intervertebral disc
Disturbed gastric emptying (GE) occurs commonly in critically ill patients. Admission diagnoses are believed to influence the incidence of delayed GE and subsequent feed intolerance. Although patients with burns and head injury are considered to be at greater risk, the true incidence has not been determined by examination of patient groups of sufficient number. This study aimed to evaluate the impact of admission diagnosis on GE in critically ill patients.
A retrospective review of patient demographics, diagnosis, intensive care unit (ICU) admission details, GE, and enteral feeding was performed on an unselected cohort of 132 mechanically ventilated patients (94 males, 38 females; age 54 ± 1.2 years; admission Acute Physiology and Chronic Health Evaluation II [APACHE II] score of 22 ± 1) who had undergone GE assessment by 13C-octanoic acid breath test. Delayed GE was defined as GE coefficient (GEC) of less than 3.20 and/or gastric half-emptying time (t50) of more than 140 minutes.
Overall, 60% of the patients had delayed GE and a mean GEC of 2.9 ± 0.1 and t50 of 163 ± 7 minutes. On univariate analysis, GE correlated significantly with older age, higher admission APACHE II scores, longer length of stay in ICU prior to GE measurement, higher respiratory rate, higher FiO2 (fraction of inspired oxygen), and higher serum creatinine. After these factors were controlled for, there was a modest relationship between admission diagnosis and GE (r = 0.48; P = 0.02). The highest occurrence of delayed GE was observed in patients with head injuries, burns, multi-system trauma, and sepsis. Delayed GE was least common in patients with myocardial injury and non-gastrointestinal post-operative respiratory failure. Patients with delayed GE received fewer feeds and stayed longer in ICU and hospital compared to those with normal GE.
Admission diagnosis has a modest impact on GE in critically ill patients, even after controlling for factors such as age, illness severity, and medication, which are known to influence this function.
Delayed gastric emptying and feed intolerance occur frequently in the critically ill. In these patients, gastric motor responses to nutrients are disturbed. Peptide YY (PYY) slows gastric emptying. The aim of this study was to determine fasting and nutrient-stimulated plasma PYY concentrations and their relationship to cholecystokinin (CCK) in critically ill patients.
Studies were performed in 19 unselected mechanically ventilated critically ill patients (12 males; 48 ± 7 years old) in a randomised, single-blind fashion. Subjects received a 60-minute duodenal infusion of Ensure® at either 1 or 2 kcal/minute. Blood samples were collected at baseline and at 20, 40, 60, and 180 minutes following commencement of the nutrient infusion for the measurement of plasma PYY and CCK concentrations (using radioimmunoassay). Patient data were compared to 24 healthy subjects (17 males; 43 ± 2 years old).
Fasting PYY concentration was higher in patients (P < 0.05), particularly in those with feed intolerance (P < 0.05). Plasma PYY concentrations were higher in patients during nutrient infusion (area under the curve [AUC] at 1 kcal/minute: 2,265 ± 718 versus 1,125 ± 138 pmol/l.min, P < 0.05; at 2 kcal/minute: 2,276 ± 303 versus 1,378 ± 210 pmol/l.min, P = 0.01) compared to healthy subjects. The magnitude of PYY elevation was greater in patients during the 1 kcal/minute infusion (AUC: 441 ± 153 versus 186 ± 58 pmol/l.min, P < 0.05), but not the 2 kcal/minute infusion. Fasting and nutrient-stimulated plasma CCK concentrations were higher in patients (P < 0.05). There was a relationship between plasma PYY and CCK concentrations during fasting (r = 0.52, P < 0.05) and nutrient infusion (r = 0.98, P < 0.0001).
In critical illness, both fasting and nutrient-stimulated plasma PYY concentrations are elevated, particularly in patients with feed intolerance, in conjunction with increased CCK concentrations.
The significant advances achieved in the care of children with cancer have been the result of carefully conducted clinical trials in international cooperative group settings. Specialized biological testing of tumour specimens is now an essential component of risk and treatment assignment for many childhood cancers. Thus, the appropriate collection and handling of tumour specimens is crucial to maintaining and further advancing the excellent outcomes that we have achieved. We recommend that all children with a strongly suspected malignancy, or cases in which the situation is unclear, be discussed with a paediatric oncologist before obtaining a tumour specimen. When a tumour is discovered incidentally at surgery, we recommend that the tumour be placed in a saline-soaked gauze and a paediatric pathologist or oncologist contacted immediately. Further progress in understanding and treating childhood cancer is intimately linked to basic studies of biology, translational research and determining the role of biological markers in risk stratification. Early and careful collaboration between front-line physicians and tertiary care oncology specialists is essential to the continuing success of treatment of children with cancer.
Paediatric cancer; Pathology
Problem A retrospective audit of surveillance for Barrett's oesophagus 1996-2001 identified the need to improve adherence to guidelines for the endoscopic surveillance of patients with Barrett's oesophagus.
Design Prospective audit of the effect of disseminating guidelines in 2002. Prospective audit of the effect of introducing local guidelines and Barrett's oesophagus surveillance officers, 2003-2005.
Setting Two general hospitals in Australia, 2002-5. All adult patients diagnosed with Barrett's oesophagus were included.
Key measures for improvement Proportions of patients in a Barrett's oesophagus surveillance programme who had appropriate time intervals between follow-up endoscopies and who had appropriate numbers of biopsies collected at endoscopy.
Strategies for change Local guidelines were laid down. Surveillance coordinators for Barrett's oesophagus were introduced to manage the process according to a clinical protocol designed for each patient.
Effects of change Disseminating guidelines had little effect on practice. Six months after surveillance coordinators were introduced, adherence to the planned surveillance interval increased from 17% to 92% and the number of endoscopies at which sufficient biopsies were collected increased from 45% to 83%. These changes have been maintained.
Lessons learnt Disseminating guidelines and results of an audit on endoscopic surveillance in Barrett's oesophagus had no effect on practice. Introducing coordinators who proactively managed the process greatly improved adherence to guidelines.
18-hydroxycortisol (18-OHF) and 18-oxocortisol (18oxo-F) are derivatives of cortisol found in Primary Aldosteronism but whose origin and regulation in normal subjects is uncertain. 18-OHF can be synthesised by zona fasciculata 11-β hydroxylase; 18-oxoF can only be produced by zona glomerulosa aldosterone synthase (AS). Stably transfected cell lines expressing either CYP11B1 (11β-hydroxylase) or CYP11B2 (AS) were incubated with cortisol and other substrates over a range of concentrations. Both enzymes could synthesise 18-OHF from cortisol but only AS could synthesise 18-oxoF. AS was more efficient than 11β-hydroxylase at 18-hydroxylation. The apparent Km of AS for cortisol was estimated to be 2.6μM. In 5 patients with adrenal insufficiency maintained on hydrocortisone, urinary free cortisol and cortisone levels were high; 18-oxoF was detectable in all patients and 18-hydroxycortisol in 3. It is likely that the 18-oxygenated steroids were synthesised from circulating cortisol, either in the zona glomerulosa or at extra-adrenal sites. In 8 male volunteers, dexamethasone treatment decreased urinary excretion rates of free cortisol, cortisone, 18-OHF and 18-oxoFl, confirming dependence of 18-oxygenated steroid levels on cortisol availability. In both groups, hydrocortisone administration resulted in detectable levels of 18-OHF and raised levels of 18-oxoF. There was close correlation between 18-oxoF and cortisol excretion during hydrocortisone administration in normal subjects (r=0.86, p<0.001).
These data show, for the first time, that 18-OHF and 18oxoF can be synthesised from circulating cortisol. The close correlation between 18-oxoF and cortisol suggests that 18-oxoF is normally produced by the action of aldosterone synthase utilising circulating cortisol as a substrate. Although 18OHF can be synthesized using circulating cortisol as substrate, our data suggest this is normally produced in the zona fasciculata by 11β-hydroxylase from locally available cortisol.
To investigate whether light drinking in pregnancy is associated with adverse child mental health and academic outcomes.
Using data from the prospective, population-based Avon Longitudinal Study of Parents and Children (ALSPAC), we investigated the associations between light drinking in pregnancy (<1 glass per week in the first trimester) and child mental health (using both parent and teacher rated Strengths and Difficulties Questionnaires (SDQs)) and academic outcomes based on Key Stage 2 examination results at age 11 years.
11-year-old children from ALSPAC with parent (n=6587) and teacher (n=6393) completed SDQs and data from Key Stage 2 examination results (n=10 558).
39% of women had consumed <1 glass per week and 16% ≥1 glass per week of alcohol during the first trimester (45% abstaining). After adjustment, relative to abstainers, there was no effect of light drinking on teacher-rated SDQ scores or examination results. In girls, although there was a suggestion of worse outcomes (adjusted regression coefficient=0.38; 95% CI 0.01 to 0.74) on the parent-rated total SDQ score in those exposed to light drinking compared to abstainers, no dose–response relationship was evident.
Although the pattern of findings involving parent ratings for girls exposed to light drinking is consistent with earlier findings from this cohort, the overall lack of any adverse effects of light drinking is similar to findings from other recent cohort studies. Light drinking in pregnancy does not appear to be associated with clinically important adverse effects for mental health and academic outcomes at the age of 11 years.
Epidemiology; Child Psychiatry
ABO blood groups were determined in 404 patients who had cardiac surgery for heart disease; 136 of these patients had rheumatic valvular heart disease and 268 had congenital heart disease. The incidence of each ABO blood group was compared to a control series of 2171 patients by means of the ϰ2 test. There was no statistical difference in the incidence of ABO blood group when patients with congenital and rheumatic valvular heart disease were compared with the control group.