Comparison of suspected and confirmed internal EVD-related infections: a prospective multi-centre U.K. observational study

Background

Diagnosis of internal external ventricular drain (EVD)-related infections (iERI) is an area of diagnostic difficulty. Empiric treatment is often initiated on clinical suspicion. There is limited guidance around antimicrobial management of confirmed versus suspected iERI.

Methods

Data on patients requiring EVD insertion were collected from 21 neurosurgical units in the United Kingdom from 2014 to 2015. Confirmed iERI was defined as clinical suspicion of infection with positive cerebrospinal fluid (CSF) culture and/or Gram stain. Cerebrospinal fluid, blood, and clinical parameters and antimicrobial management were compared between the 2 groups. Mortality and Modified Rankin Scores were compared at 30 days post-EVD insertion.

Results

Internal EVD-related infection was suspected after 46 of 495 EVD insertions (9.3%), more common after an emergency insertion. Twenty-six of 46 were confirmed iERIs, mostly due to Staphylococci (16 of 26). When confirmed and suspected infections were compared, there were no differences in CSF white cell counts or glucose concentrations, nor peripheral blood white cell counts or C-reactive protein concentrations. The incidence of fever, meningism, and seizures was also similar, although altered consciousness was more common in people with confirmed iERI. Broad-spectrum antimicrobial usage was prevalent in both groups with no difference in median duration of therapy (10 days [interquartile range {IQR}, 7–24.5] for confirmed cases and 9.5 days [IQR, 5.75–14] for suspected, P = 0.3). Despite comparable baseline characteristics, suspected iERI was associated with lower mortality and better neurological outcomes.

Conclusions

Suspected iERI could represent sterile inflammation or lower bacterial load leading to false-negative cultures. There is a need for improved microbiology diagnostics and biomarkers of bacterial infection to permit accurate discrimination and improve antimicrobial stewardship.

Am I Autistic? Utility of the Girls Questionnaire for Autism Spectrum Condition as an Autism Assessment in Adult Women

This study aimed to explore the structure of a modified version of the Girls Questionnaire for Autism Spectrum Condition (GQ-ASC; Attwood et al. 2011) to test its utility as an autism screening measure for adult women. We recruited 672 cisgender and trans women aged between 18 and 72 online. The sample contained 350 autistic women (M age = 36.21, standard deviation [SD] = 10.10) and 322 nonautistic women (M age = 34.83, SD = 9.93), screened using the Autism Quotient. A principal component analysis and parallel analysis revealed a five-component solution that accounted for 40.40% of the total variance. The extracted components appear to be consistent with what is known about the way girls and women display their autistic traits and interpreted as (1) Imagination and play: Describes interest in fantasy, fiction, and reflection on the quality and content of imaginative play in childhood. (2) Camouflaging: Describes effortful attempts to reduce the visibility of autistic traits. (3) Sensory sensitivities: Describes sensory processing hyper- and hyposensitivities across various modalities. (4) Socializing: Describes barriers to social understanding and participation. (5) Interests: Describes age-advanced and nonstereotypically feminine interests. We observed significant differences between autistic and nonautistic women across all extracted components, and the total score. A receiver operating characteristic analysis indicated an excellent level of discrimination. When applying a cutoff score of 57, the GQ-ASC correctly identified 80.0% of cases. The modified GQ-ASC is an effective and highly discriminant screening tool for use in adult autistic women. It provides valuable insight into the shared features and experiences of this underrecognized and underrepresented subset of the autistic community.

Lay summary

Why was this study done?: A lot of autistic women do not get an accurate or timely autism diagnosis. We know that when they do receive an autism diagnosis, they often feel stronger in their identity and feel more confident in advocating for their needs. We wanted to find a quick and easy way for professionals to work out which women should be referred for an autism assessment. We also wanted to help autistic women who do not want to have an assessment done feel confident in self-identifying as autistic.What did the researchers do?: We changed the wording of an autism questionnaire that was designed for younger girls, and had 350 adult autistic cisgender and trans women aged between 18 and 71 years complete it. We looked at answers in a way that told us which questions were most useful for telling apart autistic women and nonautistic women.What were the results of the study?: We found that a number of questions were grouped together into different areas that were common for autistic women. These areas were as follows: (1)Imagination and play: Questions about interest in fantasy, fiction, and imaginative play in childhood.(2)Camouflaging: Questions about acting in certain ways to try to hide autistic traits.(3)Sensory sensitivities: Questions about feeling undersensitive or oversensitive to things such as touch, small, taste, and noise.(4)Socializing: Questions about feeling confused in social situations, and finding it difficult to join in.(5)Interests: Questions about interests that are not common for children who are the same age, and interests that are not common for many girls.What do these findings add to what was already known?: There are a lot of ideas about autism that do not always apply to autistic women. These findings will hopefully help professionals and nonexperts understand autistic women better.What are potential weaknesses in the study?: We do not know if any of the 350 autistic women who completed the survey have an intellectual disability, and we do not know if having an intellectual disability will change the results of the study. This is something that will be interesting to look into in the future.How will these findings help autistic adults now and in the future?: The findings of our study can help doctors and mental health professionals work out which women should be assessed for autism. Our findings may also help to change attitudes about who can be autistic, and what autism looks like.

Healthcare communication distress scale: Pilot factor analysis and validity

OBJECTIVE

To develop psychometrically an evidence-based, patient-centred measure of patient-practitioner communication. We explored the underlying constructs of a self-report questionnaire measuring adult patients' enduring perceptions of their emotional experiences when communicating with primary healthcare practitioners.

METHODS

A cross-sectional on-line survey included 16 items from a piloted questionnaire, as well as existing measures of generalised anxiety, psychological distress, and body vigilance. Exploratory factor analysis and hierarchical multiple regression were used to explore underlying constructs in an Australian sample (N = 220).

RESULTS

A 6-item communication distress factor and a 3-item environmental arousal factor were supported, indicating good face validity and internal consistency. Bivariate correlations support convergent and discriminant validity for both factors. Hierarchical analysis exploring predictors of communication distress included sex, age, and chronic condition status; and scores on body vigilance, anxiety, distress, and environmental arousal in healthcare. Environmental arousal was the most important significant predictor of communication distress.

CONCLUSION

The patient communication questionnaire can be developed into a brief scale to measure patient distress associated with engaging with, and communicating in, healthcare settings.

PRACTICE IMPLICATIONS

A brief self-report measure to identify patients' communication distress and environmental arousal could assist in clinical practice and provide useful data in healthcare communication research.

Comparison of ventricular drain location and infusion test in hydrocephalus

OBJECTIVES

Suspected cerebrospinal fluid shunt (CSF) dysfunction in hydrocephalic patients poses a diagnostic uncertainty. The clinical picture can be non-specific and CT imaging alone is not always pathognomonic. Infusion tests are an increasingly used investigation for real-time hydrodynamic assessment of shunt patency. We report the correlation between infusion test results with the quality of ventricular drain placement on CT scans in a large retrospective group of hydrocephalic patients.

MATERIALS & METHODS

Three hundred and six infusion test results performed in 200 patients were correlated with 306 corresponding CT head scans. Nominal logistic regression was used to correlate shunt catheter position on CT imaging to patency of ventricular drain as determined by infusion tests.

RESULTS

Infusion test results of shunt patency are statistically congruent with the analysis of shunt catheter position on CT head scans. Catheter tips completely surrounded by either parenchyma or CSF on CT imaging are strongly associated with evidence of occlusion or patency from infusion tests, respectively (χ² = 51.68, P < 0.0001, n = 306 and χ² = 31.04, P < 0.0001, n = 306).

CONCLUSIONS

The most important anatomical factor for shunt patency is the catheter tip being completely surrounded by CSF. Infusion tests provide functional and reliable assessment of shunt patency in vivo and are strongly correlated with the position of the ventricular catheter on CT imaging.

Intracranial pressure, its components and cerebrospinal fluid pressure-volume compensation

Clinical measurement of intracranial pressure (ICP) is often performed to aid diagnosis of hydrocephalus. This review discusses analysis of ICP and its components' for the investigation of cerebrospinal fluid (CSF) dynamics. The role of pulse, slow and respiratory waveforms of ICP in diagnosis, prognostication and management of hydrocephalus is presented. Two methods related to ICP measurement are listed: an overnight monitoring of ICP and a constant-rate infusion study. Due to the dynamic nature of ICP, a 'snapshot' manometric measurement of ICP is of limited use as it might lead to unreliable results. Therefore, monitoring of ICP over longer time combined with analysis of its waveforms provides more detailed information on the state of pressure-volume compensation. The infusion study implements ICP signal processing and CSF circulation model analysis in order to assess the cerebrospinal dynamics variables, such as CSF outflow resistance, compliance of CSF space, pressure amplitude, reference pressure, and CSF formation. These parameters act as an aid tool in diagnosis and prognostication of hydrocephalus and can be helpful in the assessment of a shunt malfunction.

Everyday social and conversation applications of theory-of-mind understanding by children with autism-spectrum disorders or typical development

Children with autism-spectrum disorders (ASD) often fail laboratory false-belief tests of theory of mind (ToM). Yet how this impacts on their everyday social behavior is less clear, partly owing to uncertainty over which specific everyday conversational and social skills require ToM understanding. A new caregiver-report scale of these everyday applications of ToM was developed and validated in two studies. Study 1 obtained parent ratings of 339 children (85 with autism; 230 with Asperger's; 24 typically-developing) on the new scale and results revealed (a) that the scale had good psychometric properties and (b) that children with ASD had significantly more everyday mindreading difficulties than typical developers. In Study 2, we directly tested links between laboratory ToM and everyday mindreading using teacher ratings on the new scale. The sample of 25 children included 15 with autism and 10 typical developers aged 5-12 years. Children in both groups who passed laboratory ToM tests had fewer everyday mindreading difficulties than those of the same diagnosis who failed. Yet, intriguingly, autistic ToM-passers still had more problems with everyday mindreading than younger typically-developing ToM-failers. The possible roles of family conversation and peer interaction, along with ToM, in everyday social functioning were considered.

Three-dimensional cerebrospinal fluid flow within the human ventricular system

Cerebrospinal fluid (CSF) is a Newtonian fluid and can, therefore, be modelled using computational fluid dynamics (CFD). Previous modelling of the CSF has been limited to simplified geometric models. This work describes a geometrically accurate three dimensional (3D) computational model of the human ventricular system (HVS) constructed from magnetic resonance images (MRI) of the human brain. It is an accurate and full representation of the HVS and includes appropriately positioned CSF production and drainage locations. It was used to investigate the pulsatile motion of CSF within the human brain. During this investigation CSF flow rate was set at a constant 500 ml/day, to mimic real life secretion of CSF into the system, and a pulsing velocity profile was added to the inlets to incorporate the effect of cardiac pulsations on the choroid plexus and their subsequent influence on CSF motion in the HVS. Boundary conditions for the CSF exits from the ventricles (foramina of Magendie and Lushka) were found using a "nesting" approach, in which a simplified model of the entire central nervous system (CNS) was used to examine the effects of the CSF surrounding the ventricular system (VS). This model provided time varying pressure data for the exits from the VS nested within it. The fastest flow was found in the cerebral aqueduct, where a maximum velocity of 11.38 mm/s was observed over five cycles. The maximum Reynolds number recorded during the simulation was 15 with an average Reynolds number of the order of 0.39, indicating that CSF motion is creeping flow in most of the computational domain and consequently will follow the geometry of the model. CSF pressure also varies with geometry with a maximum pressure drop of 1.14 Pa occurring through the cerebral aqueduct. CSF flow velocity is substantially slower in the areas that are furthest away from the inlets; in some areas flow is nearly stagnant.

Sustaining the cocoon: the emotional inoculation produced by complementary therapies in palliative care

The aim of this study is to explore, from a medical sociological perspective, the use of complementary therapies by palliative care nurses. This paper shows how the conceptual vocabulary developed by Giddens [Giddens A. (1990) The Consequences of Modernity. Polity Press, Cambridge; Giddens A. (1991) Modernity and Self-Identity. Polity Press, Cambridge] relating to trust, ontological security, existential anxiety and the importance of protective cocoons, facilitates understanding of the use of complementary therapies in palliative care. This is a qualitative study based on semi-structured interviews. During analysis both thematic content and narrative form of the interviews are scrutinized. Analysis shows that the concepts Giddens developed enable the use of complementary therapies to be seen in new ways. In particular, they facilitate the application of a complementary therapy being seen as an emotional inoculation. Similar to the emotional inoculation Giddens speaks about, an infant receiving from its caretaker in childhood which enables a child to have a protective cocoon which it carries round with it throughout life and can draw on when faced with difficulties, the application of a complementary therapy in palliative care can be seen in terms of a booster injection being received by an adult, from their professional caretaker, in time of particular need. This injection sustains a person's protective cocoon at a time of vulnerability.

The chimeric protein tyrosine kinase ETV6-NTRK3 requires both Ras-Erk1/2 and PI3-kinase-Akt signaling for fibroblast transformation

There is increasing interest in the potential role of the NTRK family of neurotrophin receptors in human neoplasia. These receptor protein tyrosine kinases (PTKs) are well-known mediators of neuronal cell survival and differentiation, but altered NTRK signaling has also been implicated in mesenchymal, hematopoietic, and epithelial malignancies. We recently identified a novel gene fusion involving one of the neurotrophin receptor genes, NTRK3, in the pediatric solid tumor, congenital fibrosarcoma. In these tumors (and subsequently demonstrated in several other human malignancies), a t(12;15)(p13;q25) rearrangement fuses the 3' portion of the ETV6 gene with exons encoding the PTK domain of NTRK3. The resulting ETV6-NTRK3 fusion protein functions as a chimeric PTK with potent transforming activity. However, previous studies failed to detect interactions between ETV6-NTRK3 and molecules known to link wild-type NTRK3 to its two major effector pathways, namely the Ras-Raf1-Mek1-Erk1/2 mitogenic pathway or the phosphatidylinositol 3'-kinase pathway leading to activation of the AKT survival factor. Therefore, it remains unknown whether ETV6-NTRK3 transformation involves altered NTRK3 signaling. We now report that ETV6-NTRK3 expression in NIH3T3 cells leads to constitutive activation of Mek1 and Akt, as well as to constitutively high expression of cyclin D1. ETV6-NTRK3-induced soft agar colony formation was almost completely abolished by inhibition of either the Ras-Raf1-Mek1-Erk1/2 or the phosphatidylinositol 3'-kinase-Akt pathway. Moreover, this inhibition dramatically reduced expression of cyclin D1. Our results indicate that ETV6-NTRK3 transformation involves a link between known NTRK3 signaling pathways and aberrant cell cycle progression and that Mek1 and Akt activation act synergistically to mediate these effects.

The effects of cue level, hypnotizability, and state instruction on responses to leading questions

Two sessions were conducted in which independent groups of 86 high- and 85 low-susceptible subjects, responding individually under waking or hypnotic instruction, answered high- and low-cued leading questions about a video event that depicted shooting at an airport. The two sessions were separated by 1 week, and the same questions were asked in both sessions. It was predicted that highly susceptible subjects responding under hypnotic instruction would show the most evidence of accepting false information via strongly cued leading questions. Results showed general effects for leading questions and level of susceptibility but no firm support for the involvement of hypnosis. Data are discussed in terms of both the linguistic and social factors that appear to have operated on subjects in the study, results overall highlight the strong influence of level of susceptibility on subjects' acceptance of false information.

A novel flow cytometric method for measuring protein digestion within the phagocytic vacuole of polymorphonuclear neutrophils

When rhodamine is attached to albumin at a high molar ratio its fluorescence is quenched but fluorescence is released when the protein is digested and the dye released. Using this observation it is possible to measure protein digestion within the phagocytic vacuole of neutrophils. The assay is simple, rapid and measures digestion even in the presence of abnormal phagocytosis.

Measurement of tumour reactive antibody and antibody conjugate by competition, quantitated by flow cytofluorimetry

Binding of unlabelled monoclonal antibody preparations has been assessed by competition at saturation with fluorochrome labelled homologous antibody for binding to antigen bearing target cells. The extent of competition was measured by quantitative flow cytofluorimetry, and simple mathematical procedures have been developed to allow the interpretation of competition data in terms of antibody binding activity. In the system studied, non-specific (non-competitive) fluorescence was minimal, but an iterative method to calculate its contribution to the measured signal is given. This approach has the advantage that the antibody preparation to be tested does not need to be labelled or modified; this is particularly important when evaluating the binding activity of therapeutic antibody conjugates. Comparison with a well characterized standard antibody preparation provides a rapid, sensitive and accurate quality control procedure. This test is also simple to perform, requiring only the mixing of labelled and unlabelled antibodies with target cells, a single incubation, followed by analysis without washing of the target cells.

Perturbational effects of inorganic cations on human erythrocyte membranes

The perturbational effects of monovalent and divalent cations on human erythrocyte membranes were analyzed by examining their influence on kinetic and structural characteristics of trinitrobenzenesulfonic acid (TNBS) incorporation into the amino groups of protein and phospholipid structural components. The stimulatory effects of monovalent cations on TNBS incorporation, which were size-independent and attributed to nonspecific membrane alterations resulting from ionic strength factors, contrasted with the more pronounced stimulatory properties of divalent cations which were markedly size-dependent. These stimulatory effects of cations on TNBS incorporation were associated with alterations not only in rate but also in activation energy in incorporation. Changes in activation energy produced by divalent cations paralleled their ability to perturb membrane protein components and probably reflected changes in probe permeation. The rate of TNBS incorporation exhibited a dependence on divalent cation ionic radius which paralleled ion-induced perturbations in the labelling of the membrane amino phospholipid phosphatidylethanolamine. Divalent cations differed both in the relative extent and in the characteristics of protein and phospholipid perturbation. Alkaline earth cations behaved as a rather homogeneous group while Ni++, Co++ and Mn++ constituted a second heterogeneous group. The influence of monovalent and divalent cations on the hemolytic behavior of intact erythrocytes paralleled their effects on TNBS incorporation into isolated membranes rather closely. It is suggested that TNBS incorporation may provide a valuable means of analyzing functionally relevant cation-induced alterations in biological membranes in general.