Combining VITEK® 2 with colistin agar dilution screening assist timely reporting of colistin susceptibility

OBJECTIVES

The rise in carbapenem resistance among Gram-negative bacteria has renewed interest in colistin. Recently, the EUCAST-CLSI Polymyxin Breakpoints Working Group declared that broth microdilution (BMD) is the only valid method for colistin susceptibility testing. BMD is not easily incorporated into the routine work of clinical laboratories, and usually this test is incorporated serially, resulting in delayed susceptibility reporting. We tested a strategy of combining VITEK^® 2 with a 2 μg/mL colistin agar dilution (VITEK^® 2/AD) screening plate to improve performance and time to reporting of colistin susceptibility.

METHODS

Colistin susceptibility for 364 clinical isolates was determined by VITEK^® 2/AD and compared with the reference standard BMD according to the ISO 20776-1:2007 and CLSI guidelines. The EUCAST colistin susceptibility breakpoint of ≤2 μg/mL was used. Escherichia coli NCTC 13846 served as quality control strain. Agreement, very major error (VME) and major error rates were determined using ISO 20776-2:2007.

RESULTS

The VME rate for VITEK^® 2 alone was 30.6% (15/49, 95% CI 18.3-45.4%), and was reduced to 10.2% (5/49, 95% CI 3.4-22.2%) using the VITEK^® 2/AD combined testing. The combined testing had categorical agreement with BMD of 97% (354/364, 95% CI 95.0-98.7%), and a major error (ME) rate of 1.6% (5/315, 95% CI 0.5-3.7%). Using the combined testing, even against challenging strains, 349 (95.8%, 95% CI 93.3-97.7%) colistin susceptibility results could be reported, and only 15 isolates required further analysis by BMD.

DISCUSSION

Our method is simple to apply and allows rapid reporting of colistin susceptibility.

Affective versus non-affective first episode psychoses: A longitudinal study

OBJECTIVE

This study aimed to assess (1) whether there were clinical, neuropsychological and functional differences between and within affective and non-affective psychoses at baseline and two years-follow-up and (2) to explore clinical and neuropsychological predictors of psychosocial functioning in the whole sample.

METHOD

This is a subanalysis from a multicentre, naturalistic, longitudinal prospective study ('Phenotype-genotype and environmental interaction. Application of a predictive model in first psychotic episodes'). The sample consisted of 192 patients with a first psychotic episode (FEP): 142 with non-affective psychoses and 50 with affective psychoses. Student t-tests, paired t-tests, Pearson correlations, ANOVAs and regression analyses were performed.

RESULTS

At baseline, the groups differed in perseverative errors (WCST), Premorbid Adjustment Scale (PAS), family history of psychiatric disorder, negative (PANSS) and manic symptoms (YMRS). At two years follow-up, the groups differed in all the PANSS subscales and in depressive symptoms assessed by the MADRS. When the whole sample was considered, the regression model which best explained the estimated variance in functioning at follow-up (41%) was composed by PANSS total score and verbal fluency assessed by the FAS (COWAT).

CONCLUSIONS

We found clinical and neurocognitive differences at baseline which decreased in the follow-up. Reduced performances at baseline in executive functions in combination with symptom severity (PANSS) were predictors of FEP patients' poor functional outcome.

Individual trajectories of cognitive performance in first episode psychosis: a 2-year follow-up study

Individual changes over time in cognition in patients with psychotic disorders have been studied very little, especially in the case of first episode psychosis (FEP). We aimed to establish whether change in individual trajectories in cognition over 2 years of a sample of 159 FEP patients was reliable and clinically significant, using the reliable change index (RCI) and clinically significant change (CSC) methods. We also studied a sample of 151 matched healthy controls. Patients and controls were assessed with a set of neuropsychological tests, as well as premorbid, clinical and functionality measures. We analysed the course of cognitive measures over time, using analysis of variance, and the individual trajectories in the cognitive measures with the regression-based RCI (RCI_SRB) and the CSC. The RCI_SRB showed that between 5.4 and 31.2% of the patients showed deterioration patterns, and between 0.6 and 8.8% showed improvement patterns in these tests over time. Patients showing better cognitive profiles according to RCI_SRB (worsening in zero to two cognitive measures) showed better premorbid, clinical and functional profiles than patients showing deterioration patterns in more than three tests. When combining RCI_SRB and CSC values, we found that less than 10% of patients showed improvement or deterioration patterns in executive function and attention measures. These results support the view that cognitive impairments are stable over the first 2 years of illness, but also that the analysis of individual trajectories could help to identify a subgroup of patients with particular phenotypes, who may require specific interventions.

Cr(III) removal from synthetic and industrial wastewaters by using co-gasification chars of rice waste streams

Blends of rice waste streams were submitted to co-gasification assays. The resulting chars (G1C and G2C) were characterized and used in Cr(III) removal assays from a synthetic solution. A Commercial Activated Carbon (CAC) was used for comparison purposes. The chars were non-porous materials mainly composed by ashes (68.3-92.6% w/w). The influences of adsorbent loading (solid/liquid ratio - S/L) and initial pH in Cr(III) removal were tested. G2C at a S/L of 5 mg L^-1 and an initial pH of 4.50 presented an uptake capacity significantly higher than CAC (7.29 and 2.59 mg g^-1, respectively). G2C was used in Cr(III) removal assays from an industrial wastewater with Cr(III) concentrations of 50, 100 and 200 mg L^-1. Cr(III) removal by precipitation (uptake capacity ranging from 11.1 to 14.9 mg g^-1) was more effective in G2C, while adsorption (uptake capacity of 16.1 mg g^-1) was the main removal mechanism in CAC.

Inverse association between negative symptoms and body mass index in chronic schizophrenia

BACKGROUND

We investigated whether negative symptoms, such as poor motivation or anhedonia, were associated with higher body mass index (BMI) in stable patients with schizophrenia chronically treated with antipsychotic medication.

METHODS

62 olanzapine- or clozapine-treated patients with illness duration of at least four years were selected from an international multicenter study on the characterization of negative symptoms. All participants completed the Brief Negative Symptom Scale (BNSS) and the Positive and Negative Syndrome Scale (PANSS). Bivariate correlations between BMI and negative symptoms (BNSS) were explored, as well as multiple regression analyses. We further explored the association of two principal component factors of the BNSS and BMI. Subsidiary analyses re-modeled the above using the negative symptoms subscale of the PANSS and the EMSLEY factor for negative symptoms for convergent validity.

RESULTS

Lower negative symptoms (BNSS score) were associated with higher BMI (r=-0.31; p=0.015). A multiple regression analysis showed that negative symptoms (BNSS score) and age were significant predictors of BMI (p=0.037). This was mostly driven by the motivation/pleasure factor of the BNSS. Within this second factor, BMI was negatively associated with anhedonia (r=-0.254; p=0.046) and asociality (r=-0.253; p=0.048), but not avolition (r=-0.169; p=0.188). EMSLEY score was positively associated with BNSS (r=0.873, p<0.001), but negatively associated with BMI (r=-0.308; p=0.015). The association between PANSS and BMI did not reach significance (r=-224, p=0.080).

CONCLUSIONS

We conclude that lower negative symptoms were associated with higher BMI (assessed using both the BNSS and EMSLEY) in chronic stable schizophrenia patients, mostly due to lower anhedonia and asociality levels.

Congenital Ocular Motor Apraxia

Purpose

Congenital ocular motor apraxia is a rare disease characterized by defective or absent voluntary and optically induced horizontal saccadic movements. Jerky head movements or thrusts on attempted lateral gaze are a compensatory sign. Most affected children have delayed motor and speech development. Cases associated with systemic diseases, neurologic maldevelopment, metabolic deficits, and chromosomal abnormalities have been described.

Methods

Case report and review of the scientific literature.

Results

The authors describe the ophthalmologic, pediatric, and neurologic evaluations and follow-up of a child with impaired horizontal saccades, jerky head movements, and delayed motor and speech development.

Conclusions

Congenital ocular motor apraxia is an uncommon disorder of ocular motility. Even so, ophthalmologists should be aware of the developmental delay and the other associated conditions, in order to grant the patients the multidisciplinary assistance they often require.

MR imaging biomarkers for evaluating therapeutic effects shortly after near infrared photoimmunotherapy

Near infrared photoimmunotherapy (NIR-PIT) is a new cancer treatment that combines the specificity of antibodies for targeting tumors with the toxicity induced by photon absorbers after irradiation with NIR light. The purpose of this study was to determine if MR imaging can detect changes in the MR properties of tumor within several hours of NIR-PIT. A431 cells were injected subcutaneously in the right and left dorsi of 12 mice. Six days later, the mice were injected with a photon absorber, IR700, conjugated to panitumumab, an antibody targeting epidermal growth factor receptor. One day later, only right sided tumor was exposed to NIR light (treated tumor). MRI was performed 1 day before and 1-2 hours after NIR-PIT using gadofosveset for six mice and gadopentetate dimeglumine for another six mice. T2 relaxation times, the apparent diffusion coefficient (ADC) for the following combinations of b-values: 0-1000, 200-1000 and 500-1000 s/mm2 and enhancement indices were compared before and after NIR-PIT using a two-sided paired t-test. For treated tumors, T2 relaxation time increased after NIR-PIT (p < 0.01) and all three ADC values decreased after NIR-PIT (p < 0.01). Moreover, the enhancement area under the curve (AUC) using gadofosveset increased after NIR-PIT (p = 0.02). In conclusion, prolongation of T2, reductions in ADC and increased enhancement using gadofosveset are seen within 2 hours of NIR-PIT treatment of tumors. Thus, MRI can be a useful imaging biomarker for detecting early therapeutic changes after NIR-PIT.

What Are We Missing? False-Negative Cancers at Multiparametric MR Imaging of the Prostate

Purpose To characterize clinically important prostate cancers missed at multiparametric (MP) magnetic resonance (MR) imaging. Materials and Methods The local institutional review board approved this HIPAA-compliant retrospective single-center study, which included 100 consecutive patients who had undergone MP MR imaging and subsequent radical prostatectomy. A genitourinary pathologist blinded to MP MR findings outlined prostate cancers on whole-mount pathology slices. Two readers correlated mapped lesions with reports of prospectively read MP MR images. Readers were blinded to histopathology results during prospective reading. At histopathologic examination, 80 clinically unimportant lesions (<5 mm; Gleason score, 3+3) were excluded. The same two readers, who were not blinded to histopathologic findings, retrospectively reviewed cancers missed at MP MR imaging and assigned a Prostate Imaging Reporting and Data System (PI-RADS) version 2 score to better understand false-negative lesion characteristics. Descriptive statistics were used to define patient characteristics, including age, prostate-specific antigen (PSA) level, PSA density, race, digital rectal examination results, and biopsy results before MR imaging. Student t test was used to determine any demographic differences between patients with false-negative MP MR imaging findings and those with correct prospective identification of all lesions. Results Of the 162 lesions, 136 (84%) were correctly identified with MP MR imaging. Size of eight lesions was underestimated. Among the 26 (16%) lesions missed at MP MR imaging, Gleason score was 3+4 in 17 (65%), 4+3 in one (4%), 4+4 in seven (27%), and 4+5 in one (4%). Retrospective PI-RADS version 2 scores were assigned (PI-RADS 1, n = 8; PI-RADS 2, n = 7; PI-RADS 3, n = 6; and PI-RADS 4, n = 5). On a per-patient basis, MP MR imaging depicted clinically important prostate cancer in 99 of 100 patients. At least one clinically important tumor was missed in 26 (26%) patients, and lesion size was underestimated in eight (8%). Conclusion Clinically important lesions can be missed or their size can be underestimated at MP MR imaging. Of missed lesions, 58% were not seen or were characterized as benign findings at second-look analysis. Recognition of the limitations of MP MR imaging is important, and new approaches to reduce this false-negative rate are needed. ^© RSNA, 2017 Online supplemental material is available for this article.

Properties of chars from the gasification and pyrolysis of rice waste streams towards their valorisation as adsorbent materials

Rice straw (RS), rice husk (RH) and polyethylene (PE) were blended and submitted to gasification and pyrolysis processes. The chars obtained were submitted to textural, chemical, and ecotoxic characterisations, towards their possible valorisation. Gasification chars were mainly composed of ashes (73.4-89.8wt%), while pyrolysis chars were mainly composed of carbon (53.0-57.6wt%). Silicon (Si) was the major mineral element in all chars followed by alkaline and alkaline-earth metal species (AAEMs). In the pyrolysis chars, titanium (Ti) was also a major element, as the feedstock blends contained high fractions of PE which was the main source of Ti. Gasification chars showed higher surface areas (26.9-62.9m²g^-1) and some microporosity, attributed to porous silica. On the contrary, pyrolysis chars did not present a porous matrix, mainly due to their high volatile matter content. The gasification bed char produced with 100% RH, at 850°C, with O₂ as gasification agent, was selected for further characterization. This char presented the higher potential to be valorised as adsorbent material (higher surface area, higher content of metal cations with exchangeable capacity, and lowest concentrations of toxic heavy metals). The char was submitted to an aqueous leaching test to assess the mobility of chemical species and the ecotoxic level for V. fischeri. It was observed that metallic elements were significantly retained in the char, which was attributed mainly to its alkaline character. This alkaline condition promoted some ecotoxicity level on the char eluate that was eliminated after the pH correction.

International trends in clozapine use: a study in 17 countries

OBJECTIVE

There is some evidence that clozapine is significantly underutilised. Also, clozapine use is thought to vary by country, but so far no international study has assessed trends in clozapine prescribing. Therefore, this study aimed to assess clozapine use trends on an international scale, using standardised criteria for data analysis.

METHOD

A repeated cross-sectional design was applied to data extracts (2005-2014) from 17 countries worldwide.

RESULTS

In 2014, overall clozapine use prevalence was greatest in Finland (189.2/100 000 persons) and in New Zealand (116.3/100 000), and lowest in the Japanese cohort (0.6/100 000), and in the privately insured US cohort (14.0/100 000). From 2005 to 2014, clozapine use increased in almost all studied countries (relative increase: 7.8-197.2%). In most countries, clozapine use was highest in 40-59-year-olds (range: 0.6/100 000 (Japan) to 344.8/100 000 (Finland)). In youths (10-19 years), clozapine use was highest in Finland (24.7/100 000) and in the publicly insured US cohort (15.5/100 000).

CONCLUSION

While clozapine use has increased in most studied countries over recent years, clozapine is still underutilised in many countries, with clozapine utilisation patterns differing significantly between countries. Future research should address the implementation of interventions designed to facilitate increased clozapine utilisation.

Metabolic syndrome or glucose challenge in first episode of psychosis?

Patients with schizophrenia exhibit a reduced life expectancy. Although unhealthy lifestyle or suicide risk plays a role, the main causes are diverse medical conditions such as cardiovascular diseases, type 2 diabetes mellitus and metabolic syndrome. Albeit pharmacological secondary side effects might also trigger previous conditions, studies in naïve patients reflect diverse anomalies at the onset. Patients with a first episode of psychosis, display a wide scope of metabolic abnormalities, ranging from normality till pathological values depending on the parameters studied. We attempted to evaluate the metabolic syndrome and glycemic homeostasis in a subset of antipsychotic-naïve patients with a first episode of non-affective psychosis. Patients (n = 84) showed a similar prevalence of metabolic syndrome compared with a matched control sample (n = 98) (6% vs 4%, P = 0.562), while glucose homeostasis values differed significantly (14% vs. 5%, P = 0.034). Our results suggest that metabolic syndrome is not a useful clinical condition to be evaluated in patients before pharmacological treatment. Abnormal glycemic homeostasis at the onset of the disease requires specific diagnostic tools and preventive measures in order to avoid future cardiovascular events. New strategies must be implemented in order to evaluate the cardiovascular risk and subsequent morbidity in patients at the onset of the disease.

Robotic System for MRI-guided Focal Laser Ablation in the Prostate

MRI-conditional robotic platforms have proved to be an effective approach for image guided interventions. In this study, a computer-assisted, pneumatically-actuated robot was designed, built, and tested for MRI-guided prostate cancer focal laser ablation (FLA). The robotic manipulator provides two active planar degrees of freedom (DoFs) by using a customized CoreXY frame, and one passive rotational DoF. A remote insertion mechanism improves the surgical workflow by keeping the patients inside the scanner during needle insertion. The robotic manipulator was tested in a 3T MR scanner to evaluate its MR compliance, and the results demonstrated that the signal-to-noise ratio (SNR) variation was less than 8%. The in-scanner template positioning accuracy test demonstrated that the manipulator achieves high targeting accuracy with a mean error of 0.46 mm and a standard deviation of 0.25mm. Phantom studies have shown that the needle insertion accuracy of the manipulator is within 2mm (Mean = 1.7mm, StD = 0.2mm).

Adding value to gasification and co-pyrolysis chars as removal agents of Cr3

The present work aims to assess the efficiency of chars, obtained from the gasification and co-pyrolysis of rice wastes, as adsorbents of Cr³⁺ from aqueous solution. GC and PC chars, produced in the gasification and co-pyrolysis, respectively, of rice husk and polyethylene were studied. Cr³⁺ removal assays were optimised for the initial pH value, adsorbent mass, contact time and Cr³⁺ initial concentration. GC showed a better performance than PC with about 100% Cr³⁺ removal, due to the pH increase that caused Cr precipitation. Under pH conditions in which the adsorption prevailed (pH<5.5), GC presented the highest uptake capacity (21.1mg Cr³⁺ g^-1 char) for the following initial conditions: 50mg Cr³⁺ L^-1; pH 5; contact time: 24h;L/S ratio: 1000mLg^-1. The pseudo-second order kinetic model showed the best adjustment to GC experimental data. Both the first and second order kinetic models fitted well to PC experimental data. The ion exchange was the dominant phenomenon on the Cr³⁺ adsorption by GC sample. Also, this char significantly reduced the ecotoxicity of Cr³⁺ solutions for the bacterium Vibrio fischeri. GC char proved to be an efficient material to remove Cr³⁺ from aqueous solution, without the need for further activation.

Ferumoxytol as an intraprostatic MR contrast agent for lymph node mapping of the prostate: a feasibility study in non-human primates

Background A variety of magnetic resonance (MR) lymphographic agents have been proposed for mapping the lymph nodes draining the prostate. Purpose To investigate the feasibility of using ferumoxytol (an FDA-approved iron oxide agent) for lymph node mapping of the prostate on imaging (MRI) in a non-human primate (NHP) Macaque model. Material and Methods Four NHPs weighing 5-13 kg underwent injection of ferumoxytol after a needle was introduced transrectally under MRI guidance into the prostate using a commercially available intrarectal MRI biopsy guide. Ferumoxytol was administered at dosage in the range of 0.15-0.75 mg Fe/kg in a fixed injection volume of 0.2 mL. T1-weighted MRI was performed at 3 T starting immediately and extending at least 45 min post-injection. Two readers evaluated the images in consensus. The NHPs tolerated the ferumoxytol injections at all doses with no evident side effects. Results It was determined that the lowest dose of 0.15 mg Fe/kg produced the best outcome in terms of lymph node visualization and draining nodes were reliably visualized at this dose and volume. Conclusion Thus, MRI with intraprostatic injection of ferumoxytol may be considered an effective T1 contrast agent for prospective mapping of lymph nodes draining the prostate and, thus, for attempted sentinel lymph node identification in prostate cancer. Large clinical trials to determine safety and efficacy are needed.

Pharmacogenetic study of antipsychotic induced acute extrapyramidal symptoms in a first episode psychosis cohort: role of dopamine, serotonin and glutamate candidate genes

This study investigated whether the risk of presenting antipsychotic (AP)-induced extrapyramidal symptoms (EPS) could be related to single-nucleotide polymorphisms (SNPs) in a naturalistic cohort of first episode psychosis (FEP) patients. Two hundred and two SNPs in 31 candidate genes (involved in dopamine, serotonin and glutamate pathways) were analyzed in the present study. One hundred and thirteen FEP patients (43 presenting EPS and 70 non-presenting EPS) treated with high-potency AP (amisulpride, paliperidone, risperidone and ziprasidone) were included in the analysis. The statistical analysis was adjusted by age, gender, AP dosage, AP combinations and concomitant treatments as covariates. Four SNPs in different genes (DRD2, SLC18A2, HTR2A and GRIK3) contributed significantly to the risk of EPS after correction for multiple testing (P<1 × 10(-4)). These findings support the involvement of dopamine, serotonin and glutamate pathways in AP-induced EPS.

The impact of cognitive reserve in the outcome of first-episode psychoses: 2-year follow-up study

The concept of cognitive reserve (CR) suggests that the premorbid intelligence quotient (IQ), years of education and leisure activities provide more efficient cognitive networks and therefore allow a better management of some conditions associated to cognitive impairment. Fifty-two DSM-IV diagnosed FEP subjects were matched with 41 healthy controls by age, gender and parental socio-economic status. All subjects were assessed clinically, neuropsychologically and functionally at baseline and after a two-year follow-up. To assess CR at baseline, three proxies have been integrated: premorbid IQ, years of education-occupation and leisure activities. Higher CR was associated with better cognitive, functional and clinical outcomes at baseline. The CR proxy was able to predict working memory, attention, executive functioning, verbal memory and global composite cognitive score accounting for 48.9%, 19.1%, 16.9%, 10.8% and 14.9% respectively of the variance at two-year follow-up. CR was also significantly predictive of PANSS negative scale score (12.5%), FAST global score (13.4%) and GAF (13%) at two-year follow-up. In addition, CR behaved as a mediator of working memory (B=4.123) and executive function (B=3.298) at baseline and of working memory (B=5.034) at 2-year follow-up. An additional analysis was performed, in order to test whether this mediation could be attributed mainly to the premorbid IQ. We obtained that this measure was not enough by itself to explain this mediation. CR may contribute to neuropsychological and functional outcome. Specific programs addressed to improve cognition and functioning conducted at the early stages of the illness may be helpful in order to prevent cognitive and functional decline.

Optimal high b-value for diffusion weighted MRI in diagnosing high risk prostate cancers in the peripheral zone

PURPOSE

To retrospectively determine the optimal b-value(s) of diffusion-weighted imaging (DWI) associated with intermediate-high risk cancer in the peripheral zone (PZ) of the prostate.

MATERIALS AND METHODS

Forty-two consecutive patients underwent multi b-value (16 evenly spaced b-values between 0 and 2000 s/mm² ) DWI along with multi-parametric MRI (MP-MRI) of the prostate at 3 Tesla followed by trans-rectal ultrasound/MRI fusion guided targeted biopsy of suspicious lesions detected at MP-MRI. Computed DWI images up to a simulated b-value of 4000 s/mm² were also obtained using a pair of b-values (b = 133 and 400 or 667 or 933 s/mm² ) from the multi b-value DWI. The contrast ratio of average intensity of the targeted lesions and the background PZ was determined. Receiver operator characteristic curves and the area under the curve (AUCs) were obtained for separating patients eligible for active surveillance with low risk prostate cancers from intermediate-high risk prostate cancers as per the cancer of the prostate risk assessment (CAPRA) scoring system.

RESULTS

The AUC first increased then decreased with the increase in b-values reaching maximum at b = 1600 s/mm² (0.74) with no statistically significant different AUC of DWI with b-values 1067-2000 s/mm² . The AUC of computed DWI increased then decreased with the increase in b-values reaching a maximum of 0.75 around b = 2000 s/mm² . There was no statistically significant difference between the AUC of optimal acquired DWI and either of optimal computed DWI.

CONCLUSION

The optimal b-value for acquired DWI in differentiating intermediate-high from low risk prostate cancers in the PZ is b = 1600 s/mm² . The computed DWI has similar performance as that of acquired DWI with the optimal performance around b = 2000 s/mm² .

LEVEL OF EVIDENCE

4 J. Magn. Reson. Imaging 2017;45:125-131.

Cognition and psychopathology in first-episode psychosis: are they related to inflammation?

BACKGROUND

Cognitive deficits are present from the onset of psychosis and are considered a core feature of the disorder. Increasing evidence suggests that cognitive function is associated with inflammatory processes. This study evaluated the association between cognition and inflammatory biomarkers in first-episode psychosis (FEP), in order to identify cognitive phenotypes from inflammatory expression profiles.

METHOD

A case-control study of 92 FEP patients and 80 matched controls was used. Neurocognitive assessment, including verbal ability, sustained attention, verbal memory, working memory and executive function, was performed. The expression of pro- and anti-inflammatory mediators of the main intracellular inflammatory pathway was measured in peripheral blood mononuclear cells and plasma.

RESULTS

FEP patients performed worse in all cognitive domains compared to controls and had higher expression of pro-inflammatory mediators and lower expression of anti-inflammatory mediators. In the FEP group, cognition and psychopathology were associated with inflammation. Hierarchical regression analysis showed that association between the anti-inflammatory prostaglandin 15d-PGJ2 and sustained attention on one hand, and COX-2 expression and executive function on the other, were statistically significant.

CONCLUSIONS

Our study provides evidence for an association between anti-inflammatory biomarkers and cognition in FEP. The identification of a subgroup of patients based on these measures could be useful to guide treatment programmes by providing tools to select a personalized treatment approach, but longitudinal studies are needed before. In the future, establishment of biomarkers linked to cognition would be useful to monitor the course of cognitive impairment, but substantially more data will be required. Determination of IκBα, the inhibitory protein of the pro-inflammatory transcription factor NFκB, could be useful in early phases to assess clinical severity.

Malignant catatonia and neuroleptic malignant syndrome: How different/similar are they?

Introduction

Catatonia is a neuropsychiatric syndrome that appears in medical, neurological or psychiatric conditions. There are presentation variants: “malignant catatonia” (MC) subtype shares many characteristics with the neuroleptic malignant syndrome (NMS), possibly reflecting common pathophysiology.

Objectives/methods

We present a clinical vignette and review the literature available on online databases about MC/NMS.

Results

We present a man, 41-years-old, black ethnicity, with no relevant medical history. He had two previous episodes compatible with brief psychosis, the last one in 2013, and a history of adverse reactions to low doses of antipsychotics. Since the last episode he was asymptomatic on olanzapine 2.5 mg id. He acutely presented to the Emergency Room with mutism, negativism, immobility and delusional speech, similar to the previous episodes mentioned and was admitted to a psychiatric infirmary, where his clinical condition worsened, showing muscle rigidity, hemodynamic instability, leukocytosis, rhabdomyolysis and fever. Supportive care was provided, olanzapine was suspended and electroconvulsive therapy (ECT) was initiated. After two months, he was discharged with no psychotic symptoms. He is still under ECT and no antipsychotic medication was reintroduced.

Discussion/conclusion

Many studies suggest that clinical or laboratory tests do not distinguish MC from NMS and that they are the same entity. These two conditions are life-threatening and key to treatment is a high suspicion level. There is no specific treatment; supportive care and stopping involved medications are the most widely used measures. ECT is a useful alternative to medication.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

BDNF and NGF Signalling in Early Phases of Psychosis: Relationship With Inflammation and Response to Antipsychotics After 1 Year

Previous studies have indicated systemic deregulation of the proinflammatory or anti-inflammatory balance in individuals with first-episode psychosis (FEP) that persists 12 months later. To identify potential risk/protective factors and associations with symptom severity, we assessed possible changes in plasma levels of neurotrophins (brain-derived neurotrophic factor [BDNF] and nerve growth factor [NGF]) and their receptors in peripheral blood mononuclear cells (PBMCs). Expression of the 2 forms of BDNF receptors (active TrkB-FL and inactiveTrkB-T1) in PBMCs of FEP patients changed over time, TrkB-FL expression increasing by 1 year after diagnosis, while TrkB-T1 expression decreased. The TrkB-FL/TrkB-T1 ratio (hereafter FL/T1 ratio) increased during follow-up in the nonaffective psychosis group only, suggesting different underlying pathophysiological mechanisms in subgroups of FEP patients. Further, the expression of the main NGF receptor, TrkA, generally increased in patients at follow-up. After adjusting for potential confounders, baseline levels of inducible isoforms of nitric oxide synthase, cyclooxygenase, and nuclear transcription factor were significantly associated with the FL/T1 ratio, suggesting that more inflammation is associated with higher values of this ratio. Interestingly, the FL/T1 ratio might have a role as a predictor of functioning, a regression model of functioning at 1 year suggesting that the effect of the FL/T1 ratio at baseline on functioning at 1 year depended on whether patients were treated with antipsychotics. These findings may have translational relevance; specifically, it might be useful to assess the expression of TrkB receptor isoforms before initiating antipsychotic treatment in FEPs.

Comparison of calculated and acquired high b value diffusion-weighted imaging in prostate cancer

PURPOSE

To determine whether the performance of calculated high b value diffusion-weighted images (DWI) derived from regular lower b value DWI using exponential diffusion decay models (intravoxel incoherent motion = IVIM and diffusional kurtosis = DK) is comparable to acquired high b value DWI in prostate cancer detection.

MATERIALS AND METHODS

One hundred six patients underwent diagnostic multiparametric prostate MRI at 3T using an endorectal coil. Five b value (b = 0, 188, 375, 563, 750 s/mm(2)) DWI and high b value (b = 0, 1000 and 2000 s/mm(2)) DWI were acquired. Calculated high b value (b = 1000 s/mm(2) and b = 2000 s/mm(2)) DWI were derived from the DWI dataset using DK and IVIM models. Calculated and acquired high b value DWI images were compared for lesion visibility and image quality by two experienced radiologists (1 and 6 years of experience). GEE with Wald test was used to compare the image quality among the four calculated high b value DWI by comparing the proportion of lesions in each model which were comparable to the acquired images. This comparison was done for all lesions and by lesion location (PZ or CG; low apical/anterior or apical/mid/base)

RESULTS

More lesions were visible on acquired b = 2000 s/mm(2) compared to b = 1000 s/mm(2) DWI. Calculated high b value DWI using the IVIM model had approximately the same number of lesions as acquired high b value DWI, whereas the DK model had fewer lesions than acquired images. The image quality of calculated high b value DWI was comparable to that of acquired images, and the highest quality images were obtained with b1000IVIM. The image quality of calculated b1000IVIM was the same as that of acquired DWI in apical/mid/base (98%) locations and comparable in low apical and anterior (95.4%) locations. The image quality of calculated b2000IVIM was inferior in both apical/mid/base (86.2%) locations and comparable in low apical and anterior (83.9%) locations.

CONCLUSION

Calculated high b value DWI obtained using IVIM model has same lesion visibility as that of acquired DWI. The image quality of calculated high b value DWI relative to corresponding acquired DWI decreases with increase in b value.