Extended interval dosing of natalizumab in multiple sclerosis

BACKGROUND

Natalizumab (NTZ), a monoclonal antibody to human α4β1/β7 integrin, is an effective therapy for multiple sclerosis (MS), albeit associated with progressive multifocal leukoencephalopathy (PML). Clinicians have been extending the dose of infusions with a hypothesis of reducing PML risk. The aim of the study is to evaluate the clinical consequences of reducing NTZ frequency of infusion up to 8 weeks 5 days.

METHODS

A retrospective chart review in 9 MS centres was performed in order to identify patients treated with extended interval dosing (EID) regimens of NTZ. Patients were stratified into 3 groups based on EID NTZ treatment schedule in individual centres: early extended dosing (EED; n=249) every 4 weeks 3 days to 6 weeks 6 days; late extended dosing (LED; n=274) every 7 weeks to 8 weeks 5 days; variable extended dosing (n=382) alternating between EED and LED. These groups were compared with patients on standard interval dosing (SID; n=1093) every 4 weeks.

RESULTS

17% of patients on SID had new T2 lesions compared with 14% in EID (p=0.02); 7% of patients had enhancing T1 lesions in SID compared with 9% in EID (p=0.08); annualised relapse rate was 0.14 in the SID group, and 0.09 in the EID group. No evidence of clinical or radiographic disease activity was observed in 62% of SID and 61% of EID patients (p=0.83). No cases of PML were observed in EID group compared with 4 cases in SID cohort.

CONCLUSIONS

Dosing intervals up to 8 weeks 5 days did not diminish effectiveness of NTZ therapy. Further monitoring is ongoing to evaluate if the risk of PML is reduced in patients on EID.

A prospective view of animal and human Fasciolosis

Fasciolosis, a food-borne trematodiasis, results following infection with the parasites, Fasciola hepatica and Fasciola gigantica. These trematodes greatly affect the global agricultural community, infecting millions of ruminants worldwide and causing annual economic losses in excess of US $3 billion. Fasciolosis, an important zoonosis, is classified by WHO as a neglected tropical disease with an estimated 17 million people infected and a further 180 million people at risk of infection. The significant impact on agriculture and human health together with the increasing demand for animal-derived food products to support global population growth demonstrate that fasciolosis is a major One Health problem. This review details the problematic issues surrounding fasciolosis control, including drug resistance, lack of diagnosis and the threat that hybridization of the Fasciola species poses to future animal and human health. We discuss how these parasites may mediate their long-term survival through regulation and modulation of the host immune system, by altering the host immune homeostasis and/or by influencing the intestinal microbiome particularly in respect to concurrent infections with other pathogens. Large genome, transcriptome and proteomic data sets are now available to support an integrated One Health approach to develop novel diagnostic and control strategies for both animal and human disease.

Use of a consumer market activity monitoring and feedback device improves exercise capacity and activity levels in COPD

COPD is associated with a gradual decline in physical activity, which itself contributes to a worsening of the underlying condition. Strategies that improve physical activity levels are critical to halt this cycle. Wearable sensor based activity monitoring and persuasive feedback might offer a potential solution. However it is not clear just how much intervention might be needed in this regard - i.e. whether programmes need to be tailored specifically for the target clinical population or whether more simple activity monitoring and feedback solutions, such as that offered in consumer market devices, might be sufficient. This research was carried out to investigate the impact of 4 weeks of using an off the shelf consumer market activity monitoring and feedback application on measures of physical activity, exercise capacity, and health related quality of life in a population of 10 Stage I and II COPD patients. Results demonstrate a significant and positive effect on exercise capacity (measured using a 6-minute walk test) and activity levels (measured in terms of average number of steps per hour) yet no impact on health related quality of life (St Georges Respiratory Disease Questionnaire).

Smartphone derived movement profiles to detect changes in health status in COPD patients - A preliminary investigation

Over 3.2 million people in the UK alone have the lung disease Chronic Obstructive Pulmonary Disease. Identifying when COPD patients are at risk of an exacerbation is a major problem and there is a need for smart solutions that provide us with a means of tracking patient health status. Smart-phone sensor technology provides us with an opportunity to automatically monitor patients. With sensors providing the ability to measure aspects of a patient's daily life, such a motion, methods to interpret these signals and infer health related information are needed. In this work we aim to investigate the feasibility of utilizing motion sensors, built within smartphones, to measure patient movement and to infer the health related information about the patient. We perform experiments, based on 7 COPD patients using data collected over a 12 week period for each patient, and identify a measure to distinguish between periods when a patient feels well Vs periods when a patient feels unwell.

Fasciola hepatica tegumental antigens indirectly induce an M2 macrophage-like phenotype in vivo

The M2 subset of macrophages has a critical role to play in host tissue repair, tissue fibrosis and modulation of adaptive immunity during helminth infection. Infection with the helminth, Fasciola hepatica, is associated with M2 macrophages in its mammalian host, and this response is mimicked by its excretory-secretory products (FhES). The tegumental coat of F. hepatica (FhTeg) is another major source of immune-modulatory molecules; we have previously shown that FhTeg can modulate the activity of both dendritic cells and mast cells inhibiting their ability to prime a Th1 immune response. Here, we report that FhTeg does not induce Th2 immune responses but can induce M2-like phenotype in vivo that modulates cytokine production from CD4(+) cells in response to anti-CD3 stimulation. FhTeg induces a RELMα expressing macrophage population in vitro, while in vivo, the expression of Arg1 and Ym-1/2 but not RELMα in FhTeg-stimulated macrophages was STAT6 dependent. To support this finding, FhTeg induces RELMα expression in vivo prior to the induction of IL-13. FhTeg can induce IL-13-producing peritoneal macrophages following intraperitoneal injection This study highlights the important role of FhTeg as an immune-modulatory source during F. hepatica infection and sheds further light on helminth-macrophage interactions.

Relatives' matched with staff's experience of the moment of death in a tertiary referral hospital

BACKGROUND

Although the majority of deaths occur in hospital it has been suggested that dying in hospital is largely a negative experience.

AIM

To explore the experience of relatives and staff of patients dying in hospital using qualitative grounded theory.

METHODS

Patients receiving palliative care were identified who were likely to die in hospital. Family members were met by the researcher prior to the patient's death. The ward nurse and doctor (excluding palliative care team) most involved at that time were interviewed within 48 h of the death. The family were interviewed 2 weeks later. Interviewees described their experience of the patient's dying and death. Recruitment and thematic analysis of interviews occurred concurrently.

RESULTS

Twelve triads over 6 months (relative, nurse and doctor) were interviewed in relation to 12 patients. Dying patients and families need a guide to attend to their needs. Every detail is remembered by the family who take up residence in the hospital. Families value acts of kindness by staff. Hospital may offer benefits for the dying patient and family. However, there are gaps in care identified by families and staff. After death is critical time for the family. Junior doctors are often uncertain of their role, expressing grief and guilt. Young nurses inexperienced in care of dying patients value support and guidance by senior colleagues.

CONCLUSION

Leadership from nursing and medical staff is required for seamless provision of competent and compassionate care at this life changing time for grieving families.

IL-25 and innate lymphoid cells induce pulmonary fibrosis (P4357)

Disease conditions associated with pulmonary fibrosis are progressive and have a poor long-term prognosis with irreversible changes in airway architecture leading to marked morbidity and mortalities. Currently there are limited effective therapeutics for pulmonary fibrosis due to an inadequate understanding of the pathogenic process and underlying mechanisms. We now show that in human idiopathic pulmonary fibrosis (IPF) the cytokine interleukin (IL)-25 positively correlates with periostin a marker human pulmonary fibrosis, and the presence of IL-13-producing type 2 innate lymphoid cells (ILC2) in the lung. Using murine models of pulmonary fibrosis we demonstrate an essential role for IL-25-elicited ILC2 in the generation of pulmonary collagen deposition, independent of an adaptive T cell response. Furthermore, we define a mechanism whereby IL-25 evokes ILC2 to induce pulmonary fibrosis via the alternative activation of macrophages in the lung. Collectively, we present a new innate mechanism for the generation of pulmonary fibrosis, via IL-25 and ILC2 that occurs independently of T cell-mediated antigen-specific immune responses. These results indicate that IL-25 and ILC2 are potential therapeutic targets for the treatment of human fibrotic diseases where antigen-independent damage responses may magnify the disease.

Modest elevation in BNP in asymptomatic hypertensive patients reflects sub-clinical cardiac remodeling, inflammation and extracellular matrix changes

In asymptomatic subjects B-type natriuretic peptide (BNP) is associated with adverse cardiovascular outcomes even at levels well below contemporary thresholds used for the diagnosis of heart failure. The mechanisms behind these observations are unclear. We examined the hypothesis that in an asymptomatic hypertensive population BNP would be associated with sub-clinical evidence of cardiac remodeling, inflammation and extracellular matrix (ECM) alterations. We performed transthoracic echocardiography and sampled coronary sinus (CS) and peripheral serum from patients with low (n = 14) and high BNP (n = 27). Peripheral BNP was closely associated with CS levels (r = 0.92, p<0.001). CS BNP correlated significantly with CS levels of markers of collagen type I and III turnover including: PINP (r = 0.44, p = 0.008), CITP (r = 0.35, p = 0.03) and PIIINP (r = 0.35, p = 0.001), and with CS levels of inflammatory cytokines including: TNF-α (r = 0.49, p = 0.002), IL-6 (r = 0.35, p = 0.04), and IL-8 (r = 0.54, p<0.001). The high BNP group had greater CS expression of fibro-inflammatory biomarkers including: CITP (3.8±0.7 versus 5.1±1.9, p = 0.007), TNF-α (3.2±0.5 versus 3.7±1.1, p = 003), IL-6 (1.9±1.3 versus 3.4±2.7, p = 0.02) and hsCRP (1.2±1.1 versus 2.4±1.1, p = 0.04), and greater left ventricular mass index (97±20 versus 118±26 g/m², p = 0.03) and left atrial volume index (18±2 versus 21±4, p = 0.008). Our data provide insight into the mechanisms behind the observed negative prognostic impact of modest elevations in BNP and suggest that in an asymptomatic hypertensive cohort a peripheral BNP measurement may be a useful marker of an early, sub-clinical pathological process characterized by cardiac remodeling, inflammation and ECM alterations.

Peroxiredoxin: a central player in immune modulation

Peroxiredoxins (Prx) are a family of anti-oxidants that protect cells from metabolically produced reactive oxygen species (ROS). The presence of these enzymes in the secretomes of many parasitic helminths suggests they provide protection against ROS released by host immune effector cells. However, we recently reported that helminth-secreted Prx also contribute to the development of Th2-responses via a mechanism involving the induction of alternatively activated macrophages. In this review, we discuss the role helminth Prx may play in modulating the immune responses of their hosts.

Paraoxonase 1 arylesterase activity and mass are reduced and inversely related to C-reactive protein in patients on either standard or home nocturnal hemodialysis

Human serum paraoxonase (PON1) activity is reduced in standard hemodialysis (SHD) (4 hours, 3 days/week) patients. Home nocturnal hemodialysis (HNHD) (8 hours, 6 days/week), provides a greater dialysis dose resulting in a greater clearance of metabolites. Whether improvements in the metabolic milieu of HNHD patients results in different PON1 activity levels compared to SHD patients is unclear. We determined serum PON1 mass and arylesterase activities in a group of HNHD patients and compared them to SHD patients and a group of healthy controls (HC).

PATIENTS AND METHODS

We measured PON1 arylesterase activity and mass, C-reactive protein (CRP), cystatin C, total and high-density lipoprotein (HDL) cholesterol, triglycerides, apolipoproteins A-I and B in 15 HNHD, 15 SHD and 15 HC participants.

RESULTS

PON1 arylesterase activity (p < 0.001) and mass (p < 0.05) were significantly higher in HC participants compared to SHD and HNHD participants, although no significant differences were noted between HD groups. CRP (p < 0.05) was significantly higher in SHD compared to HC participants and there were no significant differences noted between HD groups. Cystatin C (p < 0.001) was significantly different among the 3 groups. There were no significant differences noted in any lipoprotein parameters among the groups. PON1 activity (r = -0.636, p < 0.001) and mass (r = -0.425, p = 0.019) were inversely correlated with CRP in HD patients.

CONCLUSION

PON1 is reduced in HNHD patients compared to HC subjects, independent of the concentration of HDL cholesterol. Within subjects on HD, the combination of increased CRP and reduced PON1 may identify subjects at a high risk for cardiovascular complications.

Validation of the confusion assessment method in the palliative care setting

The Confusion Assessment Method (CAM) is widely used in the palliative care setting despite the fact that its performance in this population has not been validated. The aim of the study was to determine the sensitivity and specificity of the CAM when used by Non-Consultant Hospital Doctors (NCHDs) working in a specialist palliative care unit. A pilot phase was performed in which NCHDs received a 1-hour training session based on the original CAM training manual. 32 patients underwent 33 assessments in the pilot phase but the sensitivity of the CAM was only 0.5 (0.22-0.78) and specificity was 1.0 (0.81-1.0). An 'enhanced' training programme was devised that took place over two 1-hour sessions and involved case-based learning focused on the areas where the NCHDs were experiencing difficulty. 52 patients underwent 54 assessments in the main phase of the study and the performance of the CAM improved significantly. Sensitivity was 0.88 (0.62-0.98) and specificity was 1.0 (0.88-1.0). The results suggest that the CAM is a valid screening tool for delirium in the palliative care setting but its performance is dependent on the skill of the operator. NCHDs require a certain standard of training before becoming proficient in its use.

Reversibility of delirium in terminally ill patients and predictors of mortality

In this study, factors related to reversibility and mortality in consecutive cases of Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) delirium [n = 121] occurring in palliative care patients were evaluated. Delirium was assessed with the revised Delirium Rating Scale (DRS-R98) and Cognitive Test for Delirium (CTD). Patients were followed until recovery from delirium or death. In all, 33 patients (27%) recovered from delirium before death. Mean time until death was 39.7 +/- 69.8 days in patients with reversible delirium [n = 33] versus 16.8 +/- 10.0 days in those with irreversible delirium [n = 88; P < 0.01]. DRS-R98 and CTD scores were higher in irreversible delirium (P < 0.001) with greater disturbances of sleep, language, long-term memory, attention, vigilance and visuospatial ability. Irreversible delirium was associated with greater disturbance of CTD attention and higher DRS-R98 visuospatial function. Survival time was predicted by CTD score (P < 0.001), age (P = 0.01) and organ failure (P = 0.01). Delirium was not necessarily a harbinger of imminent death. Less reversible delirium involved greater impairment of attention, vigilance and visuospatial function. Survival time is related to age, severity of cognitive impairment and evidence of organ failure.

Risk factors for the development of cephalic arch stenosis

PURPOSE

The creation of a vascular access is necessary in hemodialysis patients, including those with marginal vessels. Upper arm fistulae are attractive due to the ease of creation and of achieving high access flow rates. Cephalic arch stenosis (CAS) can lead to failure of upper arm fistulae and is increasingly identified. We hypothesized that CAS is promoted by high blood flow rates, brachiocephalic fistulae, and an angle of cephalic vein insertion approaching 90 degrees.

METHODS

All patients requiring a fistulogram between January 2004 and May 2006 had surveillance fluoroscopy of the central veins. Demographic, clinical and laboratory parameters were collected and the angle of the cephalic vein insertion measured by 3 blinded independent observers.

RESULTS

Fifty-eight patients had fistulograms and CAS was detected in 18 subjects. Significant differences between the CAS and non-CAS groups were brachiocephalic fistula site (p = 0.046), access flow (mL/min) (p = 0.012), and absence of diabetes (p = 0.03). Univariate predictors of CAS include access flow (per 100 mL/min) (p = 0.042), platelet count (p = 0.031) and calcium-phosphate product (p = 0.026). The relationship of brachiocephalic site and CAS was confounded by access flow [(per 100 mL/min)*brachiocephalic fistula site (p = 0.016)] and fistula age [brachiocephalic fistula site*fistula age (p = 0.017)]. In multivariate analysis, renovascular disease, calcium-phosphate product, platelet count and access flow (per 100 mL/min)*brachiocephalic fistula predicted CAS (p < 0.001, Negelkerke's R-Square = 0.55). The angle of insertion of the cephalic vein was not predictive for CAS.

CONCLUSIONS

CAS may be a long-term consequence of high blood flow rates. The interaction of access flow and brachiocephalic fistula supports the hypothesis that high flow through a brachiocephalic fistula promotes CAS. The multiple factors influencing cephalic arch remodeling require further research.

The Role of the Kidney in Blood Volume Regulation: The Kidney as a Regulator of the Hematocrit

The kidney plays a pivotal role in the regulation of blood volume by controlling the plasma volume and red blood cell (RBC) mass. Further, it is proposed that the kidney coordinates the relative volumes of these 2 blood components and in so doing regulates the hematocrit. This novel function as proposed is a functional concept whereby the kidney does not simply produce erythropoietin, but that the kidney regulates the hematocrit is termed the critmeter function. The kidney is unique in that it can indirectly report on blood volume as a tissue oxygen signal. It is proposed that the kidneys detect small changes in tissue oxygen tension for erythropoietin production at the critmeter, a functional unit of marginal oxygen tension within the kidneys. As the production of erythropoietin is modulated by angiotensin II, the renin-angiotensin system entrains the production of erythropoietin as part of the effector signals of the feedback loop of blood volume regulation. Collectively, the consideration of these points generates a paradigm shift in our understanding of blood volume regulation in that the role of the kidney may be expanded from simply "producing" erythropoietin to regulating the hematocrit. Further, this concept broadens the scope of the traditionally identified effector mechanisms of plasma volume regulation to include the modulation of erythropoietin production and hence RBC mass. The inclusion of both plasma volume and RBC mass as factors targeted by the effector signals recapitulates that whole blood volume is sensed and reported in the afferent signals. In summary, distinct sensing and effector mechanisms for regulating the volume of the two components of whole blood (plasma and red cell mass) are recognized. The coupling of the regulation of these 2 components of blood volume is highlighted.