Risk scores' performance and their impact on operative decision-making in left-sided endocarditis: a cohort study

The accuracy of contemporary risk scores in predicting perioperative mortality in infective endocarditis (IE) remains controversial. The aim is to evaluate the performance of existent mortality risk scores for cardiovascular surgery in IE and the impact on operability at high-risk thresholds. A single-center retrospective review of adult patients diagnosed with acute left-sided IE undergoing surgery from May 2014 to August 2019 (n = 142) was done. Individualized risk calculation was obtained according to the available mortality risk scores: EuroScore I and II, PALSUSE, Risk-E, Costa, De Feo-Cotrufo, AEPEI, STS-risk, STS-IE, APORTEI, and ICE-PCS scores. A cross-validation analysis was performed on the score with the best area under the curve (AUC). The 30-day survival was 96.5% (95%CI 91-98%). The score with worse area under the curve (AUC = 0.6) was the STS-IE score, while the higher was for the RISK-E score (AUC = 0.89). The AUC of the majority of risk scores suggested acceptable performance; however, statistically significant differences in expected versus observed mortalities were common. The cross-validation analysis showed that a large number of survivors (> 75%) would not have been operated if arbitrary high-risk threshold estimates had been used to deny surgery. The observed mortality in our cohort is significantly lower than is predicted by contemporary risk scores. Despite the reasonable numeric performance of the analyzed scores, their utility in judging the operability of a given patient remains questionable, as demonstrated in the cross-validation analysis. Future guidelines may advise that denial of surgery should only follow a highly experienced Endocarditis Team evaluation.

Independent risk factors of mortality in streptococcal infective endocarditis

Background

Streptococcal bloodstream infection (BSI) is a common cause of infective endocarditis (IE), yet prognostic factors for mortality are poorly investigated.

Purpose

To investigate risk factors associated with in-hospital and one-year mortality in streptococcal IE.

Methods

All patients with a streptococcal BSI, from 2008 to 2017, were included in a regional population-based setup. Based on microbiological identification of phylogenetic relationship, streptococcal species were classified into eight main subgroups: Anginosus, Bovis, Mitis, Mutans, Salivarius, Pyogenic, nutritionally variant streptococci, and S. pneumoniae. Data were crosslinked with nationwide registries for identification of demographics, concomitant hospitalization with IE, medical history, seasonal variation, and socioeconomic status. Patients were followed up until death or a maximum of 365 days after admittance, whichever came first. Using a multivariable adjusted Cox proportional hazard analysis, independent risk factors associated with in-hospital and one-year mortality were identified.

Results

Among 6,224 patients with a streptococcal BSI, 435 (7.0%) patients with streptococcal IE (mean age 69.0 (SD 14.8), 66% men) were included. The in-hospital mortality in IE patients was 11% (n=48), while the one-year mortality was 23% (n=100). Patients infected with species from the Bovis group had the lowest crude one-year mortality (13%), while patients infected with the Salivarius group had the highest crude mortality (36%). The proportion of deaths among women with IE were significantly higher than among men, both in-hospital (15% versus 9%, p=0.04) and after one year (29% versus 20%, p=0.02). Further, patients dying within one year had a significantly higher prevalence of ischemic heart disease (IHD) (p=0.02), congestive heart failure (CHF) (p<0.0001), cerebral vascular disease (CVD) (p=0.004), cancer (p=0.04), chronic obstructive pulmonary disease (COPD) (p=0.01), and renal disease (p=0.01) than survivors. In the adjusted analysis, age (Hazard Ratio (HR) 1.03, p=0.036) and renal disease (HR 2.46, p=0.045) were associated with higher in-hospital mortality. Furthermore, three independent significant factors associated with one-year mortality were identified; CHF (HR 2.18 [95% confidence interval (CI) 1.30–3.63]), cancer (HR 1.95 [95% CI 1.01–3.77]), and age (HR 1.03 [95% CI 1.01–1.05]) (Figure 1). However, patients infected with species from the Bovis group, had significantly lower risk of death at one-year (HR 0.30 [95% CI 0.10–0.89]) (Figure 1).

Conclusion

Having a renal disease at the time of IE diagnosis was associated with a higher in-hospital mortality in patients with streptococcal infective endocarditis. Further, congestive heart failure and cancer were associated with a higher one-year mortality, while the Bovis group was associated with a lower one-year mortality.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Zealand University Hospital Roskilde and Helsefonden (20-B-0340) Figure 1. Adjusted risk of one-year mortality

Left atrial strain predicts subclinical atrial fibrillation detected by long-term continuous rhythm monitoring in elderly high-risk individuals

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): he Innovation Fund Denmark (grant no.: 12-135225), The Research Foundation for the Capital Region of Denmark, The Danish Heart Foundation (grant no.: 11-04-R83-A3363-22625 and 18-R125-A8534-22083), Aalborg University Talent Management Programme, Arvid Nilssons Fond, Skibsreder Per Henriksen, R. og Hustrus Fond, and Medtronic

Background

Left atrial (LA) speckle tracking is a novel technique that provides detailed information on atrial function. Its utility for predicting subclinical atrial fibrillation (SCAF) is, however, not well-established.

Purpose

To investigate whether LA speckle tracking measures are associated with SCAF as detected by long-term continuous rhythm monitoring.

Methods

This was an echocardiographic substudy of a randomized controlled clinical trial that enrolled elderly individuals (≥70 years) with a CHADS2-score≥2 to either no intervention or implantation of a loop recorder (Reveal LINQ) to detect SCAF (≥6 minutes). A subset of the participants receiving a loop recorder was included in this analysis. An echocardiographic examination was performed, which included conventional measurements and LA speckle tracking. LA speckle tracking allowed for assessment of reservoir, conduit, and contraction strain. Multivariable proportional hazards Cox regression was applied to adjust for the clinical risk score (CHARGE-AF) and net reclassification index (NRI) was used to assess prognostic improvement of this score. Incidence rate curves were constructed using Poisson models.

Results

Overall, 976 participants were eligible for analysis. Median follow-up time was 3 years (interquartile range: 1.7-4.0 years), during which 284 (29%) were diagnosed with SCAF. The mean age was 74 years, 56% were male, median CHA2DS2-VASc-score was 4. A dilated LA (LA volume≥34ml/m2) was observed in 152 (16%).

LA speckle tracking revealed that both LA reservoir strain and contraction strain were univariable predictors of SCAF (HR = 1.05 (1.03-1.06) and HR = 1.07 (1.05-1.10), p < 0.001, per 1% decrease), such that decreasing reservoir and contraction strain were linearly associated with an increased risk of SCAF (figure). LA conduit strain was not a predictor of SCAF. These findings were unchanged after adjusting for the CHARGE-AF score, and both LA strain measures significantly improved the NRI when added to the CHARGE-AF score by 23% and 33%, respectively.

Even in participants with normal LA size, both reservoir and contraction strain were independent predictors of SCAF after multivariable adjustment (HR = 1.03 (1.01-1.05), p = 0.001 and HR = 1.06 (1.04-1.09), p < 0.001, per 1% decrease).

Conclusion

Decreasing left atrial reservoir and contraction strain are independently associated with an increased risk of SCAF as detected by long-term continuous monitoring and provide incremental prognostic value in addition to clinical risk score.

Abstract Figure.

Prevalence of infective endocarditis in streptococcal bloodstream infections is dependent on streptococcal species

Background

Streptococci frequently cause infective endocarditis (IE), yet the prevalence of IE in patients with bloodstream infections (BSIs) caused by different streptococcal species is unknown.

Purpose

To investigate the prevalence of IE in BSIs with different streptococcal species.

Methods

We included all patients with streptococcal BSIs, from 2008 to 2017, in a population-based setup. Based on microbiological identification of phylogenetic relationship, streptococcal species were classified into eight main groups: Anginosus, Bovis, Mitis, Mutans, Salivarius, Pyogenic, S. pneumoniae, and “other streptococci”. Using nationwide registries, we determined the prevalence of IE at streptococcal group level and at species level. In a multivariable logistic regression analysis, we investigated the risk of IE according to streptococcal species with S. pneumoniae as reference and adjusted for age, sex, ≥3 positive blood culture (BC) bottles, native valve disease, prosthetic valve, previous IE, and cardiac device.

Results

In 6,506 cases with streptococcal BSIs (mean age 68.1 years (SD 16.2), 52.8% men), the IE prevalence was 7.1% (95% CI: 6.5–7.8%). For the most common streptococcal species (>5% of BSIs), the IE prevalence was: S. pneumoniae 1.2% (95% CI: 0.8–1.6%), S. dysgalactiae 6.4% (95% CI: 4.9–8.2%), S. pyogenes 1.9% (95% CI: 0.9–3.3%), S. agalactiae 9.1% (95% CI: 6.6–12.1%), S. anginosus 4.8% (95% CI: 3.0–7.3%), and S. mitis/oralis 19.4% (95% CI: 15.6–23.5%) (Figure 1). For moderately common streptococcal species (1–5% of BSIs), the IE prevalence was: S. gallolyticus 30.2% (95% CI: 24.3–36.7%), S. salivarius 5.8% (95% CI: 2.9–10.1%), S. sanguinis 34.6% (95% CI: 26.6–43.3%), S. parasanguinis 10.3% (95% CI: 5.2–17.7), and S. gordonii 44.2% (95% CI: 34.0–54.8%). For uncommon streptococcal species (0.1–1% of BSIs), the highest IE prevalence was in S. mutans with 47.9% (95% CI: 33.3–62.8%). In a multivariable adjusted analysis using S. pneumoniae as a reference, we identified that all species except S. pyogenes were associated with a significantly higher IE risk (Figure 1). The highest associated IE risk was found in S. mutans (OR 81.3, 95% CI: 37.6–176), S. gordonii (OR 80.8, 95% CI: 43.9–149), S. sanguinis (OR 59.1, 95% CI: 32.6–107), S. gallolyticus (OR 31.0, 95% CI: 18.8–51.1), and S. mitis/oralis (OR 31.6, 95% CI: 19.8–50.5) (Figure 1).

Conclusion

The prevalence of IE in streptococcal BSIs is highly species dependent with the lowest IE prevalence observed in S. pneumoniae and S. pyogenes BSIs, whereas S. mutans, S. gordonii, S. sanguinis, S. gallolyticus and S. mitis/oralis had the highest IE prevalence and the highest associated IE risk after adjusting for IE risk factors.

Figure 1. Risk of IE in streptococcal BSIs

Funding Acknowledgement

Type of funding source: Public hospital(s). Main funding source(s): Herlev-Gentofte University Hospital

Age differences in mortality in patients undergoing surgery for infective endocarditis

Background

Infective endocarditis (IE) is associated with high mortality. Surgery may improve survival, but the intercept between benefit and harm is hard to balance and may be closely related to age.

Purpose

To examine the in-hospital and 90-day mortality in patients undergoing surgery for IE and to identify differences between age groups and type of valvular intervention.

Methods

By crosslinking nationwide Danish registries we identified patients with first-time IE undergoing surgical treatment in the period from 2000 to 2017. The study population was grouped in patients <60 years, 60–75 years, and ≥75 years of age. High-risk subgroups by age and surgical valve intervention (mitral vs aortic vs mitral+aortic) during IE admission were examined. Kaplan Meier estimates was used to identify 90-day mortality by age groups and multivariable adjusted Cox proportional hazard analysis was used to examine factors associated with 90-day mortality.

Results

We included 1,767 patients with IE undergoing surgery, 735 patients <60 years (24.1% female), 766 patients 60–75 years (25.8% female), and 266 patients >75 years (36.1% female). The proportion of patients with IE undergoing surgery was 35.3%, 26.9%, and 9.1% for patients <60 years, 60–75 years, and >75 years, respectively. For patients with IE undergoing surgery, the in-hospital mortality was 6.4%, 13.6%, and 20.3% for patients <60 years, 60–75 years, and ≥75 years of age, respectively and mortality at 90 days were 7.5%, 13.9%, and 22.3%, respectively. Factors associated with an increased risk 90-day mortality were: mitral valve surgery and a combination of mitral and aortic valve surgery as compared with isolated aortic valve surgery, patients 60–75 years and >75 years as compared with patients aged <60 years, prosthetic heart valve prior to IE admission, and diabetes, Figure. Patients >75 years undergoing a combination of mitral and aortic valve surgery had an in-hospital mortality of 36.3%.

Conclusion

In patients undergoing surgery for IE, a stepwise increase in 90-day mortality was seen for age groups, highest among patients >75 years with a 90-day mortality of more than 20%. Patients undergoing mitral and combined mitral and aortic valve surgery as compared to isolated aortic valve surgery were associated with a higher mortality. These findings may be of importance for the management strategy of patients with IE.

Mortality risk

Funding Acknowledgement

Type of funding source: None

P3665Prevalence of infective endocarditis in patients with positive blood cultures: a Danish nationwide study

Background

Increasing attention has been given to the risk of infective endocarditis (IE) in patients with certain blood stream infections (BSI). Previous studies have been conducted on selected patient cohorts, yet unselected data are sparse.

Purpose

To investigate the nationwide prevalence of diagnosed IE in BSIs with bacteria typically associated with IE.

Methods

By crosslinking nationwide registries from 2010–2016, we identified patients with BSIs typically associated with IE: Enterococcus faecalis, Staphylococcus, Streptococcus spp., and coagulase negative staphylococci (CoNS) and examined the concurrent IE prevalence. A trend test was used to examine temporal changes in the prevalence of IE.

Results

In total 60,119 BSIs, distributed with 15,407, 16,790, and 27,922 BSIs were identified in the periods of 2010–2011, 2012–2013, and 2014–2016, respectively.

Patients with E. Faecalis had the highest prevalence of diagnosed IE (16.3%) followed by S. aureus (10.2%), Streptococcus spp. (7.3%), and CoNS (1.6%) (Figure). During the study period, the prevalence of IE among patients with E. faecalis increased significantly (p=0.003), Male patients had higher prevalence of IE for all microorganisms investigated compared with females. A significant increase in the prevalence of IE was seen for E. faecalis, Streptococcus spp., and CoNS with increasing age.

Percent with endocarditis

Conclusion

For E. faecalis BSI, 1 in 6 had IE, for S. aureus BSI 1 in 10 had IE, and for Streptococcus spp. 1 in 14 had IE. Our results support screening for IE in patients with E. faecalis, S. aureus, or Streptococcus spp. BSI in order to offer appropriate therapy.

P2756Risk of stroke subsequent to infective endocarditis: a nationwide study

Background

Patients with infective endocarditis (IE) are at high risk of cerebral embolization, however little is known about the risk of stroke subsequent to IE in patients with stroke during IE admission.

Purpose

To investigate the risk of stroke after discharge of IE in patients with stroke during IE admission compared with patients without stroke during IE admission.

Methods

Using Danish nationwide registries we identified non-surgically treated patients with IE discharged alive, in the period 1996–2016. The study population was grouped in 1) patients with stroke during IE admission and 2) patients without stroke during IE admission. Crude cumulative risk of stoke were calculated using the Aalen-Johansen estimator accounting for death as a competing risk. Multivariable adjusted Cox proportional hazard analysis was used to compare the associated risk of stroke between groups. We identified differentials in the associated risk of stroke during follow-up between groups (p=0.006 for interaction with time), and follow-up was split into 0–1 year and 1–5 years time periods.

Results

We identified 4,284 patients with IE, 239 patients (5.6%) with stroke during IE admission (median age: 71.9 years, 58.2% males), and 4,045 patients (94.4%) without stroke during IE admission (median age 69.7 years, 64.8% males). The crude cumulative risk of stroke within 1 year of follow-up is shown in Figure Panel A, and with 1 to 5 years of follow-up in Figure Panel B. In multivariable adjusted analyses, the associated risk of stroke was higher in patients with stroke during IE admission within a follow-up period of 1 year, HR 3.21 (95% CI: 1.66–6.20) compared with patients without stroke during IE admission. From 1 to 5 years of follow-up, we identified no difference in the associated risk of stroke between groups, HR 0.91 (95% CI: 0.33–2.50).

Cumulative incidence of stroke

Conclusion

Non-surgically treated patients with IE who had a stroke during IE admission were at significantly higher associated risk of subsequent stroke – although not significant beyond 1 year after discharge from IE. These findings underline the need for identification of causes and mechanisms of recurrent strokes after IE to develop preventive means.

P3663Prevalence of infective endocarditis in patients with a left-sided heart valve prosthesis: a nationwide study

Background

Increasing attention has been given to patients with blood stream infection (BSI) and the concurrent prevalence of infective endocarditis (IE). However, there exist a gap in knowledge on the prevalence of IE among patients with a left-sided heart valve prosthesis and BSI.

Purpose

To examine the prevalence between different BSI and IE in patients with a left-sided heart valve prosthesis.

Methods

By linking Danish nationwide registries, we were able to identify patients with a left-sided prosthetic heart valve and first-time BSI of interest (Enterococcus faecalis, Staphylococcsus aureus, streptococci species (spp.), and coagulase negative staphylococci [CoNS]) in the period of 2010–2016. Concurrent admission for IE was identified from the Danish National Patient Registry in a period of up to 14 days after the BSI.

Results

A total of 1,465 patients with BSI were included (1,319 patients with an aortic valve prosthesis [82.6% bioprosthetic] and 146 patients with a mitral valve prosthesis [48.6% bioprosthetic]). Among the included patients, 244 had E. faecalis (median age: 78.3 years, 77.0% male), 301 had S. aureus (median age: 76.9 years, 69.1% male), 401 had streptococci spp. (median age: 78.0 years, 69.1% male) and 519 had CoNS (median age: 76.4 years, 64.2% male). The percentage of patients with a diagnosis of IE in relation to the BSI was 44.3%, 33.6%, 34.4%, and 7.9% for E. faecalis, S. aureus, streptococci spp., and CoNS, respectively. No difference in the overall results was seen by type of valve prosthesis, sex, or age group.

Percentage of patients with endocarditis

Conclusion

In patients with a left-sided heart valve prosthesis, IE was diagnosed in almost half of the patients with E. faecalis, in 1/3 with S. aureus or streptococci spp. and in 1 in 12 with CoNS BSI. Future studies may try to explain why some microbes are more likely to cause prosthetic heart valve endocarditis, than others are.

P2754Streptococcal infective endocarditis: distribution of species and their prognosis

Background

Infective endocarditis (IE) is frequently caused by streptococcal species. However, there is limited knowledge about the relationship between different streptococcal species and IE, and their associated outcomes.

Purpose

To examine the prevalence of streptococci at species level in IE, and to relate these different species to outcomes.

Methods

From 2002–2012 we prospectively collected consecutive patients with IE admitted to two tertiary heart centres covering a catchment area of 2.4 million people. The registry comprises 915 IE patients, 366 (40%) with streptococcal IE. Based on phylogenetic relationship, streptococcal species were classified into seven main groups: Mitis, Bovis, Mutans, Anginosus, Salivarius, Pyogenic and Nutritionally Variant Streptococcus (NVS). Classification at species level was not possible in 51 patients, who were excluded. Complications and prognosis of streptococcal IE were compared between the subgroups, and at species level.

Results

We included 315 patients with streptococcal IE. Mean age was 63 (IQR 52–76) years, and most were men (67%). A total of 115 patients (37%) had a previous heart valve disease, 58 (18%) had a prosthetic valve, 22 (7%) had previously had IE and 29 (9%) had a cardiac electronic device. With 148 episodes (47%) the Mitis group was the most common cause of IE. Other frequent groups were the Pyogenic group and the Bovis group, accounting for 66 (21%) and 51 (16%) of the cases, respectively. Surgery was carried out in 55% (n=173) of all cases. Patients infected with S. pneumoniae or S. agalactiae had a significantly higher rate of surgery, 72.2% (n=13) and 71.9% (n=23) respectively, whereas the Bovis group had a significantly lower rate, 35.5% (n=18) (p=0.048). The aortic valve was infected in 137 patients (43.5%), mitral valve in 105 patients (33.3%) and both valves were infected in 53 patients (16.8%). Twenty patients (6.3%) had right-sided IE, including pacemaker lead IE. There was no significant difference between the species subgroups regarding type of infected valve. Embolization and osteitis were observed in 76 (24.1%) and 30 (9.5%) patients, respectively. There was no significant difference between the species groups, as was the case with mortality: 23 patients (7.3%) died in-hospital and the one-year mortality was 16% (n=50).

Distribution of streptococcal IE

Conclusion

Species of the Mitis group were the most frequent Streptococci causing IE. Patients infected with S. pneumonia or S. agalactiae had significantly higher rate of surgery, and patients infected with S. bovis group had lower rate of surgery. There was no significant difference in rate of complications such as abscesses, embolization, osteitis or mortality between the streptococcal species.

Acknowledgement/Funding

Supported by grants from Herlev-Gentofte University Hospital Research Foundation

Dual redundant sequencing strategy: Full-length gene characterisation of 1056 novel and confirmatory HLA alleles

The high‐throughput department of DKMS Life Science Lab encounters novel human leukocyte antigen (HLA) alleles on a daily basis. To characterise these alleles, we have developed a system to sequence the whole gene from 5′‐ to 3′‐UTR for the HLA loci A, B, C, DQB1 and DPB1 for submission to the European Molecular Biology Laboratory – European Nucleotide Archive (EMBL‐ENA) and the IPD‐IMGT/HLA Database. Our workflow is based on a dual redundant sequencing strategy. Using shotgun sequencing on an Illumina MiSeq instrument and single molecule real‐time (SMRT) sequencing on a PacBio RS II instrument, we are able to achieve highly accurate HLA full‐length consensus sequences. Remaining conflicts are resolved using the R package DR2S (Dual Redundant Reference Sequencing). Given the relatively high throughput of this strategy, we have developed the semi‐automated web service TypeLoader, to aid in the submission of sequences to the EMBL‐ENA and the IPD‐IMGT/HLA Database. In the IPD‐IMGT/HLA Database release 3.24.0 (April 2016; prior to the submission of the sequences described here), only 5.2% of all known HLA alleles have been fully characterised together with intronic and UTR sequences. So far, we have applied our strategy to characterise and submit 1056 HLA alleles, thereby more than doubling the number of fully characterised alleles. Given the increasing application of next generation sequencing (NGS) for full gene characterisation in clinical practice, extending the HLA database concomitantly is highly desirable. Therefore, we propose this dual redundant sequencing strategy as a workflow for submission of novel full‐length alleles and characterisation of sequences that are as yet incomplete. This would help to mitigate the predominance of partially known alleles in the database.

T cell receptor repertoires after adoptive transfer of expanded allogeneic regulatory T cells

Regulatory T cell (T_reg ) therapy has been exploited in autoimmune disease, solid organ transplantation and in efforts to prevent or treat graft-versus-host disease (GVHD). However, our knowledge on the in-vivo persistence of transfused T_reg is limited. Whether T_reg transfusion leads to notable changes in the overall T_reg repertoire or whether longevity of T_reg in the periphery is restricted to certain clones is unknown. Here we use T cell receptor alpha chain sequencing (TCR-α-NGS) to monitor changes in the repertoire of T_reg upon polyclonal expansion and after subsequent adoptive transfer. We applied TCR-α-NGS to samples from two patients with chronic GVHD who received comparable doses of stem cell donor derived expanded T_reg . We found that in-vitro polyclonal expansion led to notable repertoire changes in vitro and that T_reg cell therapy altered the peripheral T_reg repertoire considerably towards that of the infused cell product, to different degrees, in each patient. Clonal changes in the peripheral blood were transient and correlated well with the clinical parameters. We suggest that T cell clonotype analyses using TCR sequencing should be considered as a means to monitor longevity and fate of adoptively transferred T cells.

Abundant cytomegalovirus (CMV) reactive clonotypes in the CD8(+) T cell receptor alpha repertoire following allogeneic transplantation

Allogeneic stem cell transplantation is potentially curative, but associated with post-transplantation complications, including cytomegalovirus (CMV) infections. An effective immune response requires T cells recognizing CMV epitopes via their T cell receptors (TCRs). Little is known about the TCR repertoire, in particular the TCR-α repertoire and its clinical relevance in patients following stem cell transplantation. Using next-generation sequencing we examined the TCR-α repertoire of CD8(+) T cells and CMV-specific CD8(+) T cells in four patients. Additionally, we performed single-cell TCR-αβ sequencing of CMV-specific CD8(+) T cells. The TCR-α composition of human leucocyte antigen (HLA)-A*0201 CMVpp65- and CMVIE -specific T cells was oligoclonal and defined by few dominant clonotypes. Frequencies of single clonotypes reached up to 11% of all CD8(+) T cells and half of the total CD8(+) T cell repertoire was dominated by few CMV-reactive clonotypes. Some TCR-α clonotypes were shared between patients. Gene expression of the circulating CMV-specific CD8(+) T cells was consistent with chronically activated effector memory T cells. The CD8(+) T cell response to CMV reactivation resulted in an expansion of a few TCR-α clonotypes to dominate the CD8(+) repertoires. These results warrant further larger studies to define the ability of oligoclonally expanded T cell clones to achieve an effective anti-viral T cell response in this setting.

Therapy in a subtropical climate for children with cerebral palsy. Evidence of physical and psychosocial effects?

AIM

To assess a possible therapeutic effect in children and adolescents with cerebral palsy of a habilitation programme in a warm sunny climate.

METHODS

Fifty-seven children and adolescents with cerebral palsy, all integrated with normal functioning children through mainstream schooling, received an individualized four-week habilitation programme at a habilitation centre in Lanzarote in the Canary Islands. They were clinically assessed before and after treatment, and again after three and six months. The clinical tests included gross motor function measure (GMFM) and the paediatric evaluation of disability inventory (PEDI). Mental health and self-esteem were assessed by using the youth self report (YSR), the child behaviour checklist (CBCL) and the Harter's self-perception profile. We also used focus-group interviews on all 57 parents by the end of the treatment period.

RESULTS

The study revealed some improvements in the level of physical performance. The most striking finding, however, was the lasting effect on behavioural and emotional parameters and the children's self-esteem.

CONCLUSION

Training in a warm climate may explain some of this positive effect. However, based on the focus-group interviews and its quantitative findings a more plausible explanation may be the interaction in a social setting with others in a similar situation.

Detection of a gypsy-like sequence in the genome of the cat flea Ctenocephalides felis (Bouché 1835)

The gypsy virus of Drosophila melanogaster is the first identified retrovirus of insects. Its infectious properties have been reported, and it is able to cause diverse mutations of the phenotype in the fruit fly. As a typical endogenous retrovirus, it is transmitted vertically as part of the host genome, but horizontal transmission has also been shown for the D. melanogaster gypsy virus. Using polymerase chain reaction with degenerate primers designed from the gypsy element of Drosophila subobscura, a gypsy-like sequence was amplified from the genome of the cat flea Ctenocephalides felis in a pool of laboratory and field strains. High identities with other gypsy-like sequences of Drosophila spp. can be detected. In contrast to some of these gypsy sequences, the 410-bp fragment of C. felis possesses two deletions, which are localised in the env gene region. Because of these deletions and the lack of virus particles in C. felis, the criteria for host infectivity are not fulfilled. Nevertheless, the general detection of a gypsy-like sequence in C. felis and the capability of the ectoparasite to act as transmitter of viral diseases can be of importance for the cat flea's position in the epidemiology of diseases, which are accompanied by a higher rate of mutation.

Detection of cerebral embolic signals in patients with systemic lupus erythematosus

BACKGROUND

Involvement of the CNS in systemic lupus erythematosus (SLE) is caused by several pathogenic mechanisms including cerebral embolism.

AIM

To measure the frequency of microembolic signals (MES) by using transcranial Doppler (TCD) ultrasound and to assess their association with cerebral infarction, neuropsychological dysfunction, and biochemical, sonographic and clinical variables in an unselected group of patients with SLE.

METHODS

A 1-h TCD recording from the middle cerebral artery was carried out in 55 patients with SLE having a mean age of 46 (SD 13) years. MRI of the brain, carotid artery ultrasonography with intima-media thickness and atherosclerotic plaque assessments were carried out in addition to a broad biochemical and clinical assessment. All patients underwent a neuropsychological assessment.

RESULTS

Of the 55 patients, MES were detected in 5 (9%) and cerebral infarcts were found in 9 (18%). A significant association was found between MES and cerebral infarcts and considerably more neuropsychological deficits were found in MES-positive patients compared with the negative group. MES were not associated with other clinical, sonographic and biochemical factors believed to be associated with cerebral embolism.

CONCLUSIONS

Cerebral embolism may be one of the important mechanisms responsible for the high prevalence of cerebrovascular events and the neuropsychological deficits observed in patients with SLE. Although the number of MES-positive patients was small, the lack of a significant association between MES and other known risk factors for MES suggests a complex pathogenesis for the embolisation in these patients.

The impact of nurses' opinion of client behaviour and level of social functioning on the amount of time they spend with clients

The impact of nurses' opinion of client behaviour and level of social functioning on the amount of time they spend with clients For people afflicted with different kinds of psychiatric disorder, suffering is a common denominator. The time the nurses spend with psychiatric clients may mirror their attitudes towards and feelings for these clients. The aim of this study was to investigate the connections between the time spent together and the nurses' opinion of client behaviour and social functioning in community-based psychiatry. In this quantitative study, 29 clients were assessed by 30 nurses, who answered the Global Assessment of Functioning Scale (GAF) and the Positive and Negative Syndrome Scale (PANSS). At the same time, 11,200 non-participant observations of clients were registered using the Patient Activity Classification (PAC) to investigate how they spent their time at two psychiatric group dwellings. The PAC instrument revealed that clients spent an average of 60.8% of time alone, while only 20% of their daily time was spent with the nurses. Based on a factor analysis, indices were made by setting cut-off points for the PANSS and the GAF scores, and four small groups of clients were generated: a relatively high level of social functioning and a low degree of psychiatric symptoms (A); a relatively high level of social functioning and a high degree of psychiatric symptoms (B); a low level of social functioning and a low degree of psychiatric symptoms (C); and, finally, a low level of social functioning and a high degree of psychiatric symptoms (D). The clients judged as having a low level of social functioning in combination with high degrees of psychiatric symptoms, that is, the most vulnerable and dependent individuals, receive less staff attention (18%) and are the clients who spend the most time alone (71.4%). It might be possible to interpret the results of this study in the light of a process of dehumanization.

Judging the other: psychiatric nurses' attitudes towards identified inpatients as measured by the semantic differential technique

Nurses' attitudes towards psychiatric patients can be expressed in terms of either a symptom-oriented approach or a personhood-focused approach where the latter is characterized by the ambition to establish a genuine and lasting relationship, while the former places the emphasis on correcting 'defective' patient behaviour. To study whether previous typologies found in a qualitative in-depth interview study exist in a larger quantitative investigation and, if so, to identify and describe a structure for the nurses' attitudes connected to each of the identified typologies. Six psychiatric group dwellings and six acute psychiatric hospital wards participated in the study. In all, 2700 assessments of 163 patients were sent out to 160 respondents and 2436 answers were returned, that is, the external dropout rate was 9.8%. The semantic differential technique was used. This is a method for quantifying the meaning that is attached to an identified phenomenon through series of bipolar pairs of adjectives. The scale has 57 bipolar pairs of adjectives, which estimates an unknown number of dimensions of nurses' attitudes towards an identified patient. The respondents' answers were analysed through entropy-based measures of association combined with structural plots. The analysis revealed that the four typologies existed as a delimited group, especially the groups of 'good' and 'evil' patients, while the 'crazy' and 'invisible' patients existed in a more blurred form. The analysis also revealed that the two groups, 'good' and 'evil', were connected to the nurses' ethical and aesthetic attitude structure, while the 'crazy' patients were linked to the cognitive structure and the 'invisible' patients to the empathetic structure. The study indicates that the two typologies, 'good' and 'evil', could be seen as each other's antithesis and, together with the other two typologies, 'crazy' and 'invisible', they touched upon a structure of the nurses' attitudes that was closely connected to a negative view of the patient except in one case -'the good' patients, which was probably based on his/her exterior symptoms.

Demonstration of multiple novel glycoforms of the stem cell survival factor CCg

We have investigated the presence of different glycoforms of cystatin C secreted by adult hippocampal rat-derived stem/progenitor cells (AHPs) into conditioned medium. A glycosylated form of cystatin C (CCg) has been identified previously in conditioned medium from AHPs as an autocrine/paracrine cofactor. Fibroblast growth factor-2 (FGF2) requires cooperation with CCg to support AHP survival at low density in vitro. The purpose of the present study was to investigate further if cystatin C consists of one glycoform or if several different glycoforms are secreted by AHPs in vitro. The presence of the glycoforms was studied using enzymatic deglycosylation in conjunction with gel electrophoresis and Western blotting. The glycoforms of cystatin C were isolated with a combination of gel electrophoresis and electroelution, yielding the intact glycoforms in liquid phase before enzymatic deglycosylation. Our results revealed several novel glycoforms, in contrast to previous publication. The results suggest that N- and O-linked glycans with sialic acid are attached to cystatin C. Furthermore, we have demonstrated that all glycoforms are present in conditioned medium after only 48 hr of culturing and that all nestin-positive AHPs are immunopositive against cystatin C. These findings suggest secretion of the glycoforms by cultured AHPs.

Clinical mass spectrometry in neuroscience. Proteomics and peptidomics

In this review we discuss the merits and drawbacks with the use of proteomic and peptidomic strategies for identification of proteins and peptides in their multidimensional interactions in complex biological processes. The progress in proteomics and peptidomics during the last years offer us new challenges to study changes in the protein and peptide synthesis. These strategies also offer new tools to follow post-translational modifications and other disturbed chemical processes that may be indicative of pathophysiological alteration(s). Furthermore these techniques can contribute to improvements in the diagnosis and therapy of neurodegenerative diseases, such as Alzheimer's disease, and psychiatric diseases, as depression and post traumatic stress disorders. We also consider different practical aspects of the applications of mass spectrometry in clinical neuroscience, illustrated by example from our laboratories. The new proteomic and peptidomic strategies will further enable the progress for clinical neuroscience research.

Brain cysts associated with mutation in the Aristaless related homeobox gene, ARX

The novel Aristaless related homeobox gene, ARX, is widely expressed in the brain and is thought to play a key role in the regulation of brain development. Neurological phenotypes caused by ARX mutations have recently started to unfold. We describe a 72 year old man with X-linked mental retardation due to a 24 bp duplication mutation in exon 2 of the ARX gene. Cerebral MRI showed bilateral cystic-like cavities in both the cerebral and cerebellar hemispheres. No retraction or expansion in neighbouring parenchyma was observed, there was no history of acute neurological impairment, and no risk factors for cerebrovascular disease were found. The lesions appeared to be congenital and represented benign developmental cysts, possibly caused by the ARX mutation.

Reliability and cultural applicability of the Greek version of the International Personality Disorders Examination

BACKGROUND

The International Personality Disorders Examination (IPDE) constitutes the proposal of the WHO for the reliable diagnosis of personality disorders (PD). The IPDE assesses pathological personality and is compatible both with DSM-IV and ICD-10 diagnosis. However it is important to test the reliability and cultural applicability of different IPDE translations.

METHODS

Thirty-one patients (12 male and 19 female) aged 35.25 +/- 11.08 years, took part in the study. Three examiners applied the interview (23 interviews of two and 8 interviews of 3 examiners, that is 47 pairs of interviews and 70 single interviews). The phi coefficient was used to test categorical diagnosis agreement and the Pearson Product Moment correlation coefficient to test agreement concerning the number of criteria met.

RESULTS

Translation and back-translation did not reveal specific problems. Results suggested that reliability of the Greek translation is good. However, socio-cultural factors (family coherence, work environment etc) could affect the application of some of the IPDE items in Greece. The diagnosis of any PD was highly reliable with phi >0.92. However, diagnosis of non-specific PD was not reliable at all (phi close to 0) suggesting that this is a true residual category. Diagnosis of specific PDs were highly reliable with the exception of schizoid PD. Diagnosis of antisocial and Borderline PDs were perfectly reliable with phi equal to 1.00.

CONCLUSIONS

The Greek translation of the IPDE is a reliable instrument for the assessment of personality disorder but cultural variation may limit its applicability in international comparisons.

Subcutaneous infiltration with ammonium sulphate 10% does not prolong the local anaesthetic duration of lidocaine in humans

BACKGROUND

The aim of the present study was to investigate whether a solution of ammonium sulphate and lidocaine had a prolonged duration of action compared with lidocaine alone after subcutaneous infiltration in human volunteers.

METHODS

In a double-blind, randomised, controlled trial 12 male volunteers had either 4 ml lidocaine 1% (40 mg) or a solution of 4 ml ammonium sulphate 10% and lidocaine 1% (40 mg) subcutaneously infiltrated in corresponding skin areas on the right and left calf. The duration of the local anaesthetic action of the test medications was assessed 1-6 h after the infiltrations using thresholds to mechanical (von Frey hairs) and thermal stimulation (heat detection thresholds: HDT, and heat pain detection thresholds: HPDT), and by calculation of areas under the curve (AUC) for electronic visual analogue scale (VAS) pain ratings (sampled at 2 Hz) during a heat stimulation on the test areas for 30 s with a 45 degrees C warm thermode.

RESULTS

At no assessment were thresholds to mechanical or thermal stimulation increased in favour of ammonium sulphate treated legs compared with control legs. On the contrary, HPDT were significantly lower in ammonium sulphate treated legs than control legs at the 3 h and 4 h assessment after infiltration (P<0.02). Similarly, the AUC for the VAS ratings was significantly higher in treatment legs compared with control legs 2 h and 3 h after infiltration (P<0.05).

CONCLUSION

No improvement in local anaesthetic duration of ammonium sulphate 10% plus lidocaine 1% compared with lidocaine 1% alone was demonstrated early after subcutaneous infiltration in human volunteers.

Effect of long-term oxygen therapy on cognitive and neurological dysfunction in chronic obstructive pulmonary disease

The aim of this study was to assess effect of long-term oxygen therapy (LTOT) on the function of central and autonomic nervous system in patients with hypoxaemic chronic obstructive pulmonary disease (COPD). A battery of neuropsychological tests was used together with the Short Test of Mental Status in addition to transcranial Doppler ultrasonography, and five cardiovascular tests as well as a questionnaire on autonomic function. Ten COPD patients, 4 males and 6 females, with a mean age of 65.9 +/- 7.3 (SD) years, were studied at the beginning and after 3 months of LTOT. At start PaO2 was 6.7 +/- 1.1 kPa without oxygen and 9.9 +/- 1.5 kPa after 3 months with oxygen. Our results demonstrate that neuropsychological function, cerebral blood flow velocity and autonomic function were positively influenced after 3 months of LTOT although the changes did not reach statistical significance. The COPD patients were cognitively impaired as compared to age-matched healthy controls. Our findings were consistent with the previous notion of improvement of hypoxic cognitive dysfunction by LTOT.

Transcallosal approach to the third ventricle: normative morphometric data based on magnetic resonance imaging scans, with special reference to the fornix and forniceal insertion

OBJECTIVE

The ability to visualize median-sagittal brain structures by magnetic resonance imaging (MRI) improves the planning for surgical removal of lesions located in and around the third ventricle. The transcallosal approach is the most appropriate path to the anterior part of the third ventricle. The present study was undertaken to obtain normative morphometric data, derived from sagittal MRI scans, which are necessary for operation planning that takes into account the surgical microanatomy and landmarks encountered during this approach.

METHODS

The morphometric evaluation was performed on 72 median-sagittal MRI scans. The surface landmarks for the corridor were the two points, P5 and P7, located 5 and 7 cm anterior to the central sulcus, respectively. With these two points on the cortical surface as references, a variety of measurements were made to provide quantitative information about distances between brain structures encountered during the surgical approach. In addition, various parameters were determined to characterize the different shapes of the fornix and the different types of forniceal insertion.

RESULTS

The following measurements (means) were obtained: 1) the distance between P5/P7 and the cingulate sulcus was 25.76 mm (range, 17.113-42.73 mm) with reference to P5, and 25.41 mm (range, 12.91-36.29 mm) with reference to P7; 2) the distance between the cingulate sulcus and the corpus callosum was 12.91 mm (range, 7.19-22.60 mm) with reference to P5, and 12.92 mm (range, 6.75-23.37 mm) with reference to P7; 3) the height of the corpus callosum was 6.22 mm (range, 3.07-9.00 mm) with reference to P5, and 6.92 mm (range, 3.50-13.57 mm) with reference to P7; 4) the distance between the anterior commissure and the foramen of Monro was 6.78 mm (range, 1.86-14.57 mm), independent of P5 and P7; 5) the distance between the lower margin of the corpus callosum and the upper insertion point of the fornix was 12.44 mm (range, 2.71-26.13 mm) with reference to P5, and 13.34 mm (range, 3.74-27.58 mm) with reference to P7; 6) the distance between the lower margin of the corpus callosum and the lower insertion point of the fornix was 18.08 mm (range, 9.47-29.71 mm) with reference to P5, and 18.58 mm (range, 10.48-30.40 mm) with reference to P7; and 7) the distance between the lower margin of the corpus callosum and the anterior commissure was 23.46 mm (range, 11.98-32.70 mm) with reference to P5, and 22.89 mm (range, 11.05-33.04 mm) with reference to P7. Four different insertion types between the fornix and the corpus callosum were noted and classified.

CONCLUSION

Morphometric data concerning the surrounding structures of the third ventricle have received very little attention in the literature. This morphometric study permitted definition of the surgical corridor to the third ventricle by preserving important anatomic structures such as the motor strip, genu of the corpus callosum, forniceal commissure (hippocampal commissure), anterior commissure, and forniceal columns. The detailed morphometric data obtained on median-sagittal MRI scans of the brain structures involved in the transcallosal interforniceal and/or transcallosal transforaminal approach allow for exact planning of the surgical approach.

Contrast enhanced pulsed Doppler and colour-coded duplex studies of the cranial vasculature

INTRODUCTION

The aim of this study was to assess the effect of Albunex, a vascular contrast agent based on albumin-coated air microbubbles, on pulsed Doppler and colour-coded duplex sonography of the cranial vasculature.

METHODS

Twenty healthy male volunteers received intravenous injections of contrast in single doses ranging from 0.08 to 0.30 ml/kg. Pulsed wave Doppler sonography examination and colour-coded duplex sonography were carried out in the right internal carotid artery (ICA) and middle cerebral artery (MCA) before and after i.v. contrast. The relative intensity increase of the Doppler signal was measured in decibels.

RESULTS

Transpulmonary passage of contrast occurred in sufficient amounts to enhance the intensity of the Doppler signal significantly, but the duration of this effect was short. Contrast enhancement also improved visualization of both the ICA and MCA in all subjects. For the transcranial examinations, this resulted in visualization of a greater length of the middle cerebral arteries and additional vessels in the Circle of Willis.

CONCLUSIONS

These results confirm that contrast enhancement can significantly improve the quality of Doppler examination and colour-coded duplex sonography of both the intracranial and extracranial vessels. However, the use of Albunex in neurosonology will be of limited value due to its relatively short duration.

Progressive pseudobulbar paresis, early choreiform movements, and later rigidity: appearance in two sets of dizygotic twins in the same family

In a family with two sets of dizygotic twins, three, possibly all four, siblings were affected by the same disorder. The parents were unrelated and the illness seemed limited to one generation. Onset was in the early to mid-20s with tics and choreiform movements, dysarthria, and dysphagia. Two twins had epilepsy. There was a marked dyscoordination of bulbar musculature reminiscent of pseudobulbar paresis. Involuntary movements were prominent during the first years, but then disappeared and were replaced by an akinetic-rigid parkinsonian appearance in the late stage. The intellect remained largely intact. Tendon reflexes were reduced. Varying degrees of peripheral nerve changes were seen. Two patients died after 22-24 years from causes indirectly related to the main illness. Marked degenerative changes were found in the caudate nucleus and putamen. Acanthocytes in significant numbers could not be detected in peripheral blood. Lipoproteinelectrophoresis was normal. Creatine kinase levels were moderately raised in one patient, normal in the others. Although certain clinical resemblances exist with neuroacanthocytosis, the exact nosologic status of the disorder has not been determined.

Intrinsic balancing in reconstruction of the tetraplegic hand

This article reviews 183 hand reconstructions in 135 consecutive tetraplegic patients. Comparisons were made between 103 extrinsic reconstructions with intrinsic balancing procedures and 80 extrinsic reconstructions without intrinsic balancing procedures. Extrinsic reconstructions (tendon transfers and tenodesis in the forearm muscles) were augmented by intrinsic reconstructive procedures (tendon transfers or tenodesis to improve the intrinsic balance of the fingers) in patients exhibiting digital imbalance. Intrinsic procedures included primarily the flexor digitorum superficialis (FDS) lasso procedure or the intrinsic tenodesis procedure. The patients were stratified by level of spinal cord injury and by type of extrinsic and intrinsic reconstruction. Hands reconstructed with intrinsic balancing versus without intrinsic balancing, as well as intrinsic balancing using a FDS lasso procedure versus an intrinsic tenodesis procedure, were compared with patients with the same level of spinal cord function. Patients who underwent reconstructions with intrinsic balancing had more grip strength, by an average of 13-26 N, than those who did not undergo intrinsic balancing. When different intrinsic procedures were compared, there was improvement in grip strength and function in activities of daily living for all hands, but there was no significant difference between FDS lasso or intrinsic tenodesis procedures. The indications for intrinsic balancing during extrinsic reconstruction are developed into treatment algorithms based on the senior author's surgical experience. The authors recommended that digital intrinsic procedures be included in hand reconstruction for tetraplegic patients exhibiting intrinsic imbalance to help improve digital function and provide increased grip strength.

Cervicocranial artery dissection. Detection by Doppler ultrasound and MR angiography

PURPOSE

To evaluate pulsed Doppler ultrasound and MR angiography (MRA) in the diagnosis of cervicocranial dissection.

MATERIAL AND METHODS

Fourteen patients with cervicocranial artery dissection were examined over a 3-year period. Twelve patients had dissection of the extracranial part of the internal carotid artery, and 2 had vertebral artery dissection. All patients were examined with pulsed Doppler ultrasound. In addition, all patients had conventional angiography (n = 9) and/or MR imaging including MRA (n = 9).

RESULTS

Doppler ultrasound disclosed unspecific abnormalities in 11 of 14 dissected vessels; 3 patients had false-negative Doppler findings. MRA showed vessel abnormalities in 9 of 9 patients; 2 vessels were occluded, and 7 vessels had changes typical of dissection (double lumen and/or string sign). Twelve patients had follow-up examinations with pulsed Doppler ultrasound (n = 12), conventional angiography (n = 3), and MRA/MR (n = 11). Follow-up Doppler showed complete or partial normalization in 6 of 9 patients, all confirmed by either angiography or MRA.

CONCLUSION

Our findings suggest that Doppler ultrasound may be used in follow-up of pathologic Doppler findings in known dissections, and that MRA may replace angiography in the confirmative diagnosis of cervicocranial dissection.

Assessment of the ophthalmic artery as a collateral to the cerebral circulation. A comparison of transorbital Doppler ultrasonography and regional cerebral blood flow measurements

The role of the ophthalmic artery (OA) as a collateral to the cerebral circulation in carotid occlusive disease is somewhat controversial. The aim of this study was to assess the importance of this collateral by comparing the results of transorbital Doppler ultrasonography and regional cerebral blood flow measurements using SPECT and Xenon-133 inhalation in 41 patients with unilateral high-grade internal carotid artery occlusive disease. Both measurements were performed under basal conditions and after the intravenous administration of 1 g acetazolamide to test cerebral vasoreactivity. Based on the direction of OA flow, the patients could be divided into three groups. In Group 1 (n = 16) with anterograde OA flow before and after acetazolamide, baseline rCBF values did not differ significantly between the two sides, or from those of the controls. The side-to-side asymmetry of the response to acetazolamide was also normal. In Group 2 (n = 11) where the OA flow was anterograde or "0 flow" before, but became retrograde after acetazolamide, rCBF was significantly reduced on the symptomatic compared to the non-symptomatic side under basal conditions. However, the increase in rCBF after acetazolamide was within normal limits. In Group 3 (n = 14) the OA flow was reversed both under basal conditions and after the vasodilatory stimulus. Baseline rCBF was significantly lower (p < 0.05) on the symptomatic side compared to the non-symptomatic, and the asymmetry became even greater (p < 0.001) after acetazolamide. Our findings demonstrate that the OA may be an important collateral pathway in patients with ICA occlusive disease, and contribute to the cerebral perfusion reserve in the case of compromised blood supply.