Immunoglobulin G/immunoglobulin M autoantibody ratios in incomplete systemic lupus erythematosus

OBJECTIVE

Immunoglobulin G (IgG) autoantibodies in systemic lupus erythematosus (SLE) are considered pathogenic, whereas immunoglobulin M (IgM) autoantibodies may have protective effects. The aim of this study was to identify whether IgG/IgM autoantibody ratios differ between patients with incomplete systemic lupus erythematosus (iSLE), patients with SLE, and healthy controls (HCs), and whether IgG/IgM autoantibody ratios relate to progression from iSLE to SLE.

METHOD

This prospective cohort study included 34 iSLE patients, 41 SLE patients, and 11 HCs. IgG and IgM anti-dsDNA, anti-Ro52, and anti-Ro60 were measured by fluoro-enzyme immunoassay in serum samples obtained at baseline in all groups and in follow-up samples of up to 5 years for iSLE patients. Correlations between IgG/IgM autoantibody ratios, interferon signature, and clinical parameters were also assessed.

RESULTS

At baseline, IgG anti-dsDNA, anti-Ro52, anti-Ro60, and IgM anti-dsDNA were elevated in iSLE and SLE patients. IgG/IgM anti-dsDNA and anti-Ro52 ratios were similar between groups, while IgG/IgM anti-Ro60 ratios were significantly elevated in iSLE and SLE patients compared to HCs. IgG/IgM autoantibody ratios were not correlated with interferon signature or clinical parameters. IgG/IgM ratios at baseline were similar and remained relatively stable during a median follow-up of 18 months in non-progressors and six iSLE patients who progressed to SLE.

CONCLUSION

IgG anti-dsDNA, anti-Ro52, anti-Ro60, and IgM anti-dsDNA were elevated in iSLE and SLE patients, which was not apparent from the respective IgG/IgM ratios only. IgG/IgM autoantibody ratios remained relatively stable over up to 5 years in iSLE non-progressors and six patients who progressed to SLE.

Genetic landscape of pediatric acute liver failure of indeterminate origin

BACKGROUND AND AIMS

Pediatric acute liver failure (PALF) is a life-threatening condition. In Europe, the main causes are viral infections (12%-16%) and inherited metabolic diseases (14%-28%). Yet, in up to 50% of cases the underlying etiology remains elusive, challenging clinical management, including liver transplantation. We systematically studied indeterminate PALF cases referred for genetic evaluation by whole-exome sequencing (WES), and analyzed phenotypic and biochemical markers, and the diagnostic yield of WES in this condition.

APPROACH AND RESULTS

With this international, multicenter observational study, patients (0-18 y) with indeterminate PALF were analyzed by WES. Data on the clinical and biochemical phenotype were retrieved and systematically analyzed.

RESULTS

In total, 260 indeterminate PALF patients from 19 countries were recruited between 2011 and 2022, of whom 59 had recurrent PALF. WES established a genetic diagnosis in 37% of cases (97/260). Diagnostic yield was highest in children with PALF in the first year of life (41%), and in children with recurrent acute liver failure (64%). Thirty-six distinct disease genes were identified. Defects in NBAS (n=20), MPV17 (n=8), and DGUOK (n=7) were the most frequent findings. When categorizing, the most frequent were mitochondrial diseases (45%), disorders of vesicular trafficking (28%), and cytosolic aminoacyl-tRNA synthetase deficiencies (10%). One-third of patients had a fatal outcome. Fifty-six patients received liver transplantation.

CONCLUSIONS

This study elucidates a large contribution of genetic causes in PALF of indeterminate origin with an increasing spectrum of disease entities. The high proportion of diagnosed cases and potential treatment implications argue for exome or in future rapid genome sequencing in PALF diagnostics.

Biallelic known and novel DCDC2 variants in cholestatic liver disease: phenotype-genotype observations in four children

Neonatal sclerosing cholangitis (NSC) is associated with progressing biliary fibrosis often requiring liver transplantation in childhood. Several recent studies have identified variants in DCDC2, encoding doublecortin domain-containing protein 2 (DCDC2), expressed in primary cilia, that accompany syndromic disease and NSC. We report 4 patients with hepatobiliary disease associated with two novel homozygous or compound heterozygous variants in DCDC2. Three patients with protein-truncating variants in DCDC2, expressing no DCDC2, presented with the originally described severe hepatic phenotype in infancy. One patient with a novel homozygous DCDC2 missense variant shows a markedly milder phenotype only manifest in childhood and with retained DCDC2 expression. Concomitant nephronophthisis is present in 3 patients and learning disability in 2. This report widens the phenotypic spectrum of DCDC2-associated hepatobiliary disease. Testing for DCDC2 expression and DCDC2 variants should be included in the evaluation of cholangiopathy of unknown aetiology in childhood as well as in infancy.

Comments and illustrations of the WFUMB CEUS liver guidelines: rare congenital vascular pathology

In this overview of vascular changes of the liver, variations in the liver vessels are discussed, in addition to congenital malformations such as Abernethy malformation, patent ductus venosus Arantii and hereditary hemorrhagic telangiectasia (OslerWeber-Rendu disease). Particular attention is paid to focal liver lesions, especially focal nodular hyperplasia (FNH), but also other solid tumours that develop as a result of altered liver vascularisation. The article focuses on the ultrasonic appearances and changes of the liver, depicted in B-mode sonography, Doppler studies and in contrast-enhanced ultrasonography (CEUS). The clinical manifestations of these conditions associated with other organ systems are also highlighted.

AB0347 TREATMENT RESPONSE WITH ABATACEPT PLUS METHOTREXATE TREATMENT FOR RHEUMATOID ARTHRITIS: REAL-WORLD EVIDENCE FROM THE UK

Background

A previous real-world study has reported the characteristics, treatment patterns and clinical outcomes of patients with rheumatoid arthritis (RA) who received abatacept in UK clinical practice.1,2 However, many of the eligible population received abatacept monotherapy rather than as indicated. A subgroup analysis of patients treated with abatacept in combination with methotrexate (ABA + MTX) was therefore undertaken to explore the treatment effect in this specific patient population.

Objectives

Present a subgroup analysis describing the clinical outcomes of patients with RA treated with ABA + MTX in UK real-world clinical practice.

Methods

A multi-centre, retrospective observational study was undertaken in patients with RA treated with abatacept at any line of therapy between 1 January 2013 and 31 December 2017, across four UK centres. Data were collected from patient medical records from index date, defined as the date of first bDMARD initiation, to most recent RA clinic visit, death or end of study (31 December 2017). Clinical outcomes (disease activity and response to treatment) were measured using the 28-joint Disease Activity Score based on erythrocyte sedimentation rate (DAS28-ESR) and European League Against Rheumatism (EULAR) response criteria. Patients that received abatacept outside indication (i.e., without concomitant methotrexate) were retrospectively excluded from the analysis dataset. Statistical analyses for the ABA + MTX subgroup were repeated in line with the methodology previously reported.1,2

Results

This subgroup analysis included 133 patients, of 213 patients included in the original study, with RA that received ABA + MTX (mean age 54.6 years, 77.4% female, 7.5 years mean duration of RA at index date). At index date, 64.8% of patients were positive for both anti-citrullinated protein antibodies (ACPA) and rheumatoid factor (RF), where data were available. In total, 77.8% of patients were categorised with high disease activity at index, with mean DAS28-ESR of 6.2 (SD 1.1).

Irrespective of line of treatment (LOT), patients tended to have a more favourable distribution of good/moderate/no EULAR response when receiving ABA + MTX (31.8%/34.1%/34.1%; n=44) compared with receipt of other bDMARDs (12.7%/36.4%/50.9%; n=55) at 6 months. Similarly, a favourable distribution of good/moderate/no EULAR response in favour of those receiving ABA + MTX compared with other bDMARDs was observed at 12 months (30.6%/41.7%/27.8% versus 20.0%/35.0%/45.0%, respectively).

Patients receiving ABA + MTX remained on treatment for significantly longer than patients in receipt of other bDMARDs as first LOT (median time on treatment 53.4 vs 18.1 months; p<0.01). A similar trend was observed at second LOT, although differences were not statistically significant (median time on treatment 40.1 vs 19.7 months; p =0.08).

Conclusion

Patients with RA who received treatment with any bDMARDs, including ABA + MTX, experienced reduced disease activity. However, those receiving ABA + MTX persisted with treatment significantly longer than when receiving other bDMARDs.

References

[1]Choy, E. et al. Outcomes in rheumatoid arthritis patients treated with abatacept: a UK multi-centre observational study. BMC Rheumatology5, 3, doi:10.1186/s41927-020-00173-0 (2021).

[2]Henning, S. et al. AB0295 CHANGE IN DISEASE ACTIVITY AND TREATMENT RESPONSE AFTER ABATACEPT TREATMENT FOR RHEUMATOID ARTHRITIS: REAL-WORLD EVIDENCE FROM THE UK. Annals of the Rheumatic Diseases79, 1446-1447, doi:10.1136/annrheumdis-2020-eular.1069 (2020).

Acknowledgements

This analysis was supported by Bristol-Myers Squibb.

Disclosure of Interests

Ernest Choy Speakers bureau: Abbvie, Amgen, Bristol Myer Squibbs, Chugai Pharma, Eli Lilly, Galapagos, Gilead, Janssen, Novartis, Pfizer, Regeneron, Roche, Sanofi, and UCB, Consultant of: Abbvie, Amgen, Biogen, Biocon, Chugai Pharma, Eli Lilly, Gilead, Janssen, Merck Serono, Novartis, Pfizer, Regeneron, Roche, R-Pharm and Sanofi, Grant/research support from: Bio-Cancer, Biogen, Novartis, Pfizer, Roche, Sanofi and UCB, Sadie Henning Shareholder of: Bristol Myers Squibb, Employee of: Yes, Bristol Myers Squibb, Marie Brazil Shareholder of: Bristol Myers Squibb, Employee of: Currently an employee of Bristol Myers Squibb, Kevin Pollock Shareholder of: Yes - Bristol Myers Squibb, Speakers bureau: Yes - Merck Sharp & Dohme and Glaxo Smith Kline, Consultant of: Yes - Merck Sharp & Dohme, Employee of: Yes – currently employed by Bristol Myers Squibb, Lara Groves Grant/research support from: I am an employee of Health Economics and Outcomes Research Ltd., Cardiff, UK, who received fees from Bristol Myers Squibb in relation to this study, Daniel Sugrue Grant/research support from: I am an employee of Health Economics and Outcomes Research Ltd., Cardiff, UK, who received fees from Bristol Myers Squibb in relation to this study, John Houghton Grant/research support from: I am an employee of Health Economics and Outcomes Research Ltd., Cardiff, UK, who received fees from Bristol Myers Squibb in relation to this study

Hepatic artery reconstruction using an operating microscope in pediatric liver transplantation-Is it worth the effort?

INTRODUCTION

In pediatric liver transplantation (pLT), hepatic artery thrombosis (HAT) is associated with inferior transplant outcome. Hepatic artery reconstruction (HAR) using an operating microscope (OM) is considered to reduce the incidence of HAT.

METHODS

HAR using an OM was compared to a historic cohort using surgical loupes (SL) in pLT performed between 2009 and 2020. Primary endpoint was the occurrence of HAT. Secondary endpoints were 1-year patient and graft survival determined by Kaplan-Meier analysis and complications. Multivariate analysis was used to identify independent risk factors for HAT and adverse events.

RESULTS

A total of 79 pLTs were performed [30 (38.0%) living donations; 49 (62.0%) postmortem donations] divided into 23 (29.1%) segment 2/3, 32 (40.5%) left lobe, 4 (5.1%) extended right lobe, and 20 (25.3%) full-size grafts. One-year patient and graft survival were both 95.2% in the OM group versus 86.2% and 77.8% in the SL group (p = .276 and p = .077). HAT rate was 0% in the OM group versus 24.1% in the SL group (p = .013). One-year patient and graft survival were 64.3% and 35.7% in patient with HAT, compared to 93.9% and 92.8% in patients with no HAT (both p < .001). Multivariate analysis revealed HAR with SL (p = .022) and deceased donor liver transplantation (DDLT) (p = .014) as independent risk factors for HAT. The occurrence of HAT was independently associated with the need for retransplantation (p < .001) and biliary leakage (p = .045).

CONCLUSION

In pLT, the use of an OM is significantly associated to reduce HAT rate, biliary complications, and graft loss and outweighs the disadvantages of delayed arterial perfusion and prolonged warm ischemia time (WIT).

Feasibility of percutaneous endoscopic gastrostomy insertion in children receiving peritoneal dialysis

BACKGROUND

Peritoneal dialysis (PD) is the preferred dialysis modality for paediatric patients with end-stage kidney disease. Frequently, malnutrition is encountered. Percutaneous endoscopic gastrostomy (PEG) is the preferred mode of feeding because of its minimal invasive mode of placement and easy handling in daily life. However, reports of a high risk for early post-interventional peritonitis hampered this procedure during PD and controlled studies on the benefit of peri-interventional management to prevent peritonitis are lacking. Here, we report the safety profile of PEG insertion among a cohort of children on PD by using a prophylactic antibiotic and antifungal regimen as well as modification of the PD programme.

METHODS

We performed a single-centre analysis of paediatric PD patients receiving PEG placement between 2015 and 2020. Demographic data, peri-interventional prophylactic antibiotic and antifungal treatment as well as modification of the PD programme were gathered and the incidence of peritonitis within a period of 28 days after PEG was calculated.

RESULTS

Eight PD patients (median weight 6.7 kg) received PEG insertion. Antibiotic and antifungal prophylaxis were prescribed for median time of 4.0 and 5.0 days, respectively. After individual reduction of PD intensity, all patients continued their regular PD programme after a median of 6 days. One patient developed peritonitis within 24 h after PEG insertion and simultaneous surgery for hydrocele.

CONCLUSIONS

Applying an antibiotic and antifungal prophylactic regime as well as an adapted PD programme may reduce the risk for peritonitis in paediatric PD patients who receive PEG procedure.

Regulation of the cytochrome P450 epoxyeicosanoid pathway is associated with distinct histologic features in pediatric non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a significant health burden in obese children for which there is currently no specific therapy. Preclinical studies indicate that epoxyeicosanoids, a class of bioactive lipid mediators that are generated by cytochrome P450 (CYP) epoxygenases and inactivated by the soluble epoxide hydrolase (sEH), play a protective role in NAFLD. We performed a comprehensive lipidomics analysis using liver tissue and blood samples of 40 children with NAFLD. Proteomics was performed to determine CYP epoxygenase and sEH expressions. Hepatic epoxyeicosanoids significantly increased with higher grades of steatosis, while their precursor PUFAs were unaltered. Concomitantly, total CYP epoxygenase activity increased while protein level and activity of sEH decreased. In contrast, hepatic epoxyeicosanoids showed a strong decreasing trend with higher stages of fibrosis, accompanied by a decrease of CYP epoxygenase activity and protein expression. These findings suggest that the CYP epoxygenase/sEH pathway represents a potential pharmacologic target for the treatment of NAFLD.

Gene-Dose Effect of MEFV Gain-of-Function Mutations Determines ex vivo Neutrophil Activation in Familial Mediterranean Fever

Familial Mediterranean fever (FMF) is caused by mutations within the Mediterranean fever (MEFV) gene. Disease severity depends on genotype and gene dose with most serious clinical courses observed in patients with M694V homozygosity. Neutrophils are thought to play an important role in the initiation and perpetuation of inflammatory processes in FMF, but little is known about the specific characteristics of these cells in FMF patients. To further characterize neutrophilic inflammatory responses in FMF and to delineate gene–dose effects on a cellular level, we analyzed cytokine production and activation levels of isolated neutrophils derived from patients and subjects with distinct MEFV genotypes, as well as healthy and disease controls. Serum levels of interleukin-18 (IL-18) (median 11,485 pg/ml), S100A12 (median 9,726 ng/ml), and caspase-1 (median 394 pg/ml) were significantly increased in patients with homozygous M694V mutations. Spontaneous release of S100A12, caspase-1, proteinase 3, and myeloperoxidase (MPO) was restricted to ex vivo cultured neutrophils derived from patients with two pathogenic MEFV mutations. IL-18 secretion was highest in patients with two mutations but also increased in neutrophils from healthy heterozygous MEFV mutation carriers, exhibiting an ex vivo gene–dose effect, which was formerly described by us in patients' serum. CD62L (l-selectin) was spontaneously shed from the surface of ex vivo cultured neutrophils [median of geometric mean fluorescence intensity (gMFI) after 5 h: 28.8% of the initial level]. While neutrophils derived from healthy heterozygous mutation carriers again showed a gene–dose effect (median gMFI: 67.1%), healthy and disease controls had significant lower shedding rates (median gMFI: 83.6 and 82.9%, respectively). Co-culture with colchicine and/or stimulation with adenosine triphosphate (ATP) and lipopolysaccharide (LPS) led to a significant increase in receptor shedding. Neutrophils were not prevented from spontaneous shedding by blocking IL-1 or the NLRP3 inflammasome. In summary, the data demonstrate that ex vivo cultured neutrophils derived from FMF patients display a unique phenotype with spontaneous release of high amounts of IL-18, S100A12, MPO, caspase-1, and proteinase 3 and spontaneous activation as demonstrated by the loss of CD62L. Neutrophilic activation seems to be independent from IL-1 activation and displays a gene–dose effect that may be responsible for genotype-dependent phenotypes.

AB0295 CHANGE IN DISEASE ACTIVITY AND TREATMENT RESPONSE AFTER ABATACEPT TREATMENT FOR RHEUMATOID ARTHRITIS: REAL-WORLD EVIDENCE FROM THE UK

Background:

Patients with moderate to severe active rheumatoid arthritis (RA) may be treated with biological disease-modifying antirheumatic drugs (bDMARDs), such as abatacept, after treatment failure with conventional synthetic DMARDs (csDMARDs). Abatacept has shown equivalent efficiency with other targeted therapies for RA in clinical trials and network meta-analyses. However, there is limited real-world evidence on patient outcomes associated with abatacept treatment in UK routine clinical practice.

Objectives:

To describe the clinical outcomes of RA patients treated with abatacept in UK real-world clinical practice.

Methods:

A multi-centre, retrospective observational study was undertaken in RA patients treated with abatacept at any line of therapy (LOT). Data were extracted from medical records at four UK hospitals. Patients aged 18 years or older who received abatacept between 1 January 2013 and 31 December 2017 were included. The index date was the date of first bDMARD initiation, with follow-up from index date to latest RA clinic visit, death or 31 December 2017, whichever occurred first.

Clinical outcomes (disease activity and response to treatment) were measured using the 28-joint Disease Activity Score based on erythrocyte sedimentation rate (DAS28-ESR) and European League Against Rheumatism (EULAR) response criteria1-3.

Results:

The study included 213 patients (mean age 55.2 years, 71.4% female, 7.0 years mean duration of RA at index date). Where ACPA and RF status were recorded, 66.1% of patients were anti-citrullinated protein antibodies (ACPA) and rheumatoid factor (RF) positive at index. Mean DAS28-ESR at index was 6.2 (SD 1.0) and 80.9% of patients were categorised with high disease activity.

Irrespective of LOT, changes in DAS28-ESR (where recorded) from LOT initiation among patients treated with abatacept versus other bDMARDs were -1.59 vs -1.56 (LS mean (SE): -0.04; 95% CI: -0.45,0.38; p=0.86) at 6 months and -1.98 vs -1.42 (LS mean (SE): -0.56; 95% CI: -1.04,-0.07; p=0.03) at 12 months, respectively. Table 1 shows that compared with other bDMARDs, patients treated with abatacept at any LOT experienced good response to treatment at 6 months (22.8%, n= 21/92 vs 15.9%, n= 24/151) and 12 months (27.9%, n= 17/61 vs 20.5%, n= 24/117) according to EULAR criteria.

Table1.

Treatment response at 6 and 12 months after initiation of any LOT*

EULAR response6 months12 monthsAbatacept,n = 92Other bDMARDs,n = 151Abatacept,n = 61Other bDMARDs,n = 117Good21 (22.8%)24 (15.9%)17 (27.9%)24 (20.5%)Moderate38 (41.3%)60 (39.7%)22 (36.1%)40 (34.2%)None33 (35.9%)67 (44.4%)22 (36.1%)53 (45.3%)

n = number of unique LOTs in which a patient has both a DAS28-ESR collected at initiation and 6 and/or 12 months (a patient may be included in this analysis multiple times)

Patients who received abatacept remained on treatment for significantly longer than patients who received other bDMARDs at LOT1 (median 53.4 vs 17.4 months; p<0.01) (Figure 1) and at LOT2 (median 40.1 vs 17.1 months; p<0.01).

Figure 1.

Time on treatment from first LOT initiation, abatacept versus other bDMARDs

Conclusion:

RA patients who received bDMARDs, including abatacept, experienced reduced disease activity. These findings are comparable with those from a European, multicentre, observational study on patients receiving abatacept4. The mechanisms associated with such clinical benefit should be elucidated in future research.

References:

[1]Prevoo et al. Arthritis Rheum 1995;38:44–8.

[2]Fransen & van Riel. Clin Exp Rheumatol 2005;23:S93–9.

[3]van Gestel et al. Arthritis Rheum 1998;41:1845–50.

[4]Alten et al. Clin Rheumatol (2019) 38: 1413.

Acknowledgments:

Yusuf Patel

Srinivasan Venkatachalam

James Maxwell

Usman Farooqui

Kevin Pollock

Disclosure of Interests:

Sadie Henning Shareholder of: Sadie Henning is a shareholder for Bristol-Myers Squibb Pharmaceuticals Ltd., Employee of: Sadie Henning is employed by Bristol-Myers Squibb Pharmaceuticals Ltd., Lara Groves Grant/research support from: Lara Groves is an employee of Health Economics and Outcomes Research Ltd., Cardiff, UK, who received fees from Bristol-Myers Squibb Pharmaceuticals Ltd in relation to this study., Michael Hurst Grant/research support from: Michael Hurst is an employee of Health Economics and Outcomes Research Ltd., Cardiff, UK, who received fees from Bristol-Myers Squibb Pharmaceuticals Ltd in relation to this study., Daniel Sugrue Grant/research support from: Daniel Sugrue is an employee of Health Economics and Outcomes Research Ltd., Cardiff, UK, who received fees from Bristol-Myers Squibb Pharmaceuticals Ltd in relation to this study., Jason Gordon Grant/research support from: Jason Gordon is an employee of Health Economics and Outcomes Research Ltd., Cardiff, UK, who received fees from Bristol-Myers Squibb Pharmaceuticals Ltd in relation to this study., Ernest Choy Grant/research support from: Amgen, Bio-Cancer, Chugai Pharma, Ferring Pharmaceuticals, Novimmune, Pfizer, Roche, UCB, Consultant of: AbbVie, Amgen, AstraZeneca, Biogen, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Chelsea Therapeutics, Chugai Pharma, Daiichi Sankyo, Eli Lilly, Ferring Pharmaceuticals, GlaxoSmithKline, Hospita, Ionis, Janssen, Jazz Pharmaceuticals, MedImmune, Merck Sharp & Dohme, Merrimack Pharmaceutical, Napp, Novartis, Novimmune, ObsEva, Pfizer, R-Pharm, Regeneron Pharmaceuticals, Inc., Roche, SynAct Pharma, Sanofi Genzyme, Tonix, UCB, Speakers bureau: Amgen, Boehringer Ingelheim, Bristol-Myers Squibb, Chugai Pharma, Eli Lilly, Hospira, Merck Sharp & Dohme, Novartis, Pfizer, Regeneron Pharmaceuticals, Inc., Roche, Sanofi-Aventis, UCB

0603 Divided Attention Steering Simulator Compared to Other Daytime Sleepiness Tests in Sleep Apnea

Introduction

Sleep apnea is often associated with daytime sleepiness. A test which may be similar to driving situations is the divided attention steering Simulator (DASS) as a surrogate for testing sleepiness at the wheel. In this study we compared DASS parameters against Epworth sleepiness score (ESS) and psychomotor vigilance test (PVT) in subjects with sleep apnea.

Methods

In 16 healthy subjects without sleep disorders and in 38 patients with sleep apnea, we tested daytime sleepiness and Performance using different methodologies. We applied the DASS twice, the PVT twice, the testbattery for attentional Performance (TAP), and the MSLT during one day after polysomnography.

Results

Sleep apnea patients had a longer response time according to DASS (p&lt;0.05) and a larger average deviation from midline of the road (p&lt;0.05) and left the road more frequently (p&lt;0.05). Response time in DASS correlated well with PVT (p&lt;0.001). We found no significant association between ESS and DASS parameters. We no correlation between MSLT sleep latency and DASS parameters.

Conclusion

The DASS is very well to mirror reaction time as determined by PVT. However, the DASS does not reflect sleepiness as determined by MSLT or ESS. The study confirms the finding that reaction time testing, even using different tools, does not relate very well with perceived subjective sleepiness by ESS nor by objective sleepiness as assessed by multiple sleep latency test. Different measures do form a complex Picture which might lead to falling asleep when driving. All tests do show some limitations regarding this assessment.

Support

This study was supported by Charite University funds.

Outcome after pediatric liver transplantation for staged abdominal wall closure with use of biological mesh-Study with long-term follow-up

Abdominal wall closure after pediatric liver transplantation (pLT) in infants may be hampered by graft-to-recipient size discrepancy. Herein, we describe the use of a porcine dermal collagen acellular graft (PDCG) as a biological mesh (BM) for abdominal wall closure in pLT recipients. Patients <2 years of age, who underwent pLT from 2011 to 2014, were analyzed, divided into definite abdominal wall closure with and without implantation of a BM. Primary end-point was the occurrence of postoperative abdominal wall infection. Secondary end-points included 1- and 5-year patient and graft survival and the development of abdominal wall hernia. In five out of 21 pLT recipients (23.8%), direct abdominal wall closure was achieved, whereas 16 recipients (76.2%) received a BM. BM removal was necessary in one patient (6.3%) due to abdominal wall infection, whereas no abdominal wall infection occurred in the no-BM group. No significant differences between the two groups were observed for 1- and 5-year patient and graft survival. Two late abdominal wall hernias were observed in the BM group vs none in the no-BM group. Definite abdominal wall closure with a BM after pLT is feasible and safe when direct closure cannot be achieved with comparable postoperative patient and graft survival rates.

Early Exchange Transfusion to Treat Neonates With Gestational Alloimmune Liver Disease: An 11-Year Cohort Study

OBJECTIVES

Exchange transfusion (ET) and intravenous immunoglobulin are potentially life-saving treatment options in newborns with gestational alloimmune liver disease (GALD). Since 2008, early ET has been the standard of care for symptomatic neonates with suspected GALD in our unit. The present study's aim was to investigate the outcomes of this approach.

METHODS

From 2008 to 2018, all neonates who received ET for suspected GALD were identified, and their clinical course and outcomes were analyzed in a descriptive cohort study. In survivors, liver function parameters before ET and maximum values after ET and at discharge were compared.

RESULTS

During the 11-year period, 12 infants received ET for suspected GALD at a median (range) chronological age of 11 (1-23) days and gestational age of 38 (32-40) weeks. Signs of impaired liver function, most frequently postnatal hypoglycemia, hyperferritinemia, direct hyperbilirubinemia, and coagulopathy, were present in all infants. Survival without a liver transplant in the overall cohort was 10 of 12 (83.3%) and 7 of 9 (78%) in those fulfilling the criteria of acute liver failure. Two patients died, one of them after liver transplantation. Direct bilirubin typically increased after ET, even in survivors. All survivors recovered and were discharged from the pediatric hepatology outpatient clinic after 8 (3-11) months of follow-up.

CONCLUSIONS

In newborns with suspected GALD, a limited diagnostic work-up followed by early ET may lead to favorable outcomes. More data are required to develop an evidence-based clinical approach to GALD.

Single-Pass Albumin Dialysis in the Treatment of Children with Liver Failure

BACKGROUND AND AIMS

Acute and acute on chronic liver failure are life-threatening conditions, and bridging to transplantation is complicated by a paucity of suitable organs for children. While different modalities of extracorporeal liver support exist, their use in children is complicated by a large extracorporeal volume, and data on their use in children is limited. The aim of this analysis was to investigate the efficacy and safety of single-pass albumin dialysis (SPAD) in children with liver failure.

METHODS

Retrospective medical chart review of pediatric patients with liver failure treated with SPAD. The decrease in hepatic encephalopathy (HE) and the serum levels of bilirubin and ammonia were measured to determine efficacy. Adverse events were documented to assess safety.

RESULTS

Nineteen pediatric patients with a median age of 25.5 months and a median body weight of 11.9 kg were treated with SPAD between January 2011 and March 2018. Total bilirubin (p < 0.001) and ammonia (p = 0.02) significantly decreased after treatment with SPAD. As clinical outcome parameter, HE significantly improved (p = 0.001). Twelve patients were bridged successfully to liver transplantation. In all patients, 71 SPAD sessions were run. Clotting in the dialysis circuit was observed in 49% of all sessions. Heparin and citrate were used for anticoagulation and were significantly superior to dialysis without any anticoagulation (p= 0.03). Transfusion of packed blood cells (57%) and catecholamine therapy (49%) were frequently necessary.

CONCLUSIONS

Treatment with SPAD was effective in detoxification, as measured by significant improvement of HE and clearance from surrogate laboratory parameters.

Genetic determinants of steatosis and fibrosis progression in paediatric non-alcoholic fatty liver disease

BACKGROUND AND AIMS

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children and adolescents today. In comparison with adult disease, paediatric NAFLD may show a periportal localization, which is associated with advanced fibrosis. This study aimed to assess the role of genetic risk variants for histological disease pattern and severity in childhood NAFLD.

METHODS

We studied 14 single nucleotide polymorphisms (SNP) in a cohort of 70 adolescents with biopsy-proven NAFLD. Genotype was compared to an adult control cohort (n = 200) and analysed in relation to histological disease severity and liver tissue proteomics.

RESULTS

Three of the 14 SNPs were significantly associated with paediatric NAFLD after FDR adjustment, rs738409 (PNPLA3, P = 2.80 × 10^-06 ), rs1044498 (ENPP1, P = 0.0091) and rs780094 (GCKR, P = 0.0281). The severity of steatosis was critically associated with rs738409 (OR=3.25; 95% CI: 1.72-6.52, FDR-adjusted P = 0.0070). The strongest variants associated with severity of fibrosis were rs1260326, rs780094 (both GCKR) and rs659366 (UCP2). PNPLA3 was associated with a portal pattern of steatosis, inflammation and fibrosis. Proteome profiling revealed decreasing levels of GCKR protein with increasing carriage of the rs1260326/rs780094 minor alleles and downregulation of the retinol pathway in rs738409 G/G carriers. Computational metabolic modelling highlighted functional relevance of PNPLA3, GCKR and UCP2 for NAFLD development.

CONCLUSIONS

This study provides evidence for the role of PNPLA3 as a determinant of portal NAFLD localization and severity of portal fibrosis in children and adolescents, the risk variant being associated with an impaired hepatic retinol metabolism.

UVA-induced DNA double-strand breaks result from the repair of clustered oxidative DNA damages

UVA (320-400 nm) represents the main spectral component of solar UV radiation, induces pre-mutagenic DNA lesions and is classified as Class I carcinogen. Recently, discussion arose whether UVA induces DNA double-strand breaks (dsbs). Only few reports link the induction of dsbs to UVA exposure and the underlying mechanisms are poorly understood. Using the Comet-assay and γH2AX as markers for dsb formation, we demonstrate the dose-dependent dsb induction by UVA in G(1)-synchronized human keratinocytes (HaCaT) and primary human skin fibroblasts. The number of γH2AX foci increases when a UVA dose is applied in fractions (split dose), with a 2-h recovery period between fractions. The presence of the anti-oxidant Naringin reduces dsb formation significantly. Using an FPG-modified Comet-assay as well as warm and cold repair incubation, we show that dsbs arise partially during repair of bi-stranded, oxidative, clustered DNA lesions. We also demonstrate that on stretched chromatin fibres, 8-oxo-G and abasic sites occur in clusters. This suggests a replication-independent formation of UVA-induced dsbs through clustered single-strand breaks via locally generated reactive oxygen species. Since UVA is the main component of solar UV exposure and is used for artificial UV exposure, our results shine new light on the aetiology of skin cancer.

The ground state phase diagram of the diluted ferromagnetic Kondo-lattice model

We investigate the existence of several (anti-)ferromagnetic phases in the diluted ferromagnetic Kondo-lattice model, i.e. ferromagnetic coupling of local moment and electron spin. To do this we use a coherent potential approximation (CPA) with a dynamical alloy analogy. For the CPA we need effective potentials, which we obtain first from a mean-field approximation. To improve this treatment we use in the next step a more appropriate moment conserving decoupling approach and compare the two methods. The different magnetic phases are modeled by defining two magnetic sub-lattices. As a result we present zero-temperature phase diagrams according to the important model parameters and different dilutions.

Nanocrystalline hydroxyapatite for bone repair: an animal study

Abstract Hydroxyapatite has become the most common material to replace bone or to guide its regeneration. Nanocrystalline hydroxyapatite suspension had been introduced in the clinical use recently under the assumption that small dimension of crystals could improve resorption. We studied the resorption and osteointegration of the nanocrystalline hydroxyapatite Ostim in a rabbit model. The material was implanted either alone or in combination with autogenic or allogenic bone into distal rabbit femora. After survival time of 2, 4, 6, 8 and 12 weeks the implants had been evaluated by light and electron microscopy. We observed a direct bone contact as well as inclusion into soft tissue. But we could observe no or only marginal decay and no remarkable resorption in the vast majority of implants. In situ the nanocrystalline material mostly formed densely packed agglomerates which were preserved once included in bone or connective tissue. A serious side effect was the initiation of osteolysis in the femora far from the implantation site causing extended defects in the cortical bone.

A case of cerebral Whipple's disease initially presenting with isolated focal myoclonus

Neurological manifestations in Whipple's disease are highly variable and tend to occur at later stages of the disease. However, isolated, focal neurological symptoms are reported to be rare. Here we describe the successful treatment of a case of cerebral Whipple's disease initially presenting solely with isolated myoclonic jerks of the left hand and forearm evolving to a segmental myoclonus at a later stage. Additionally, we present - to our knowledge - a novel treatment by administration of immunomodulatory therapy (IVIg) in addition to established antibiotics.

Task- and EEG-correlated analyses of BOLD MRI responses to eyes opening and closing

Variations of a subject's vigilance may pose a severe confound during functional brain mapping. Here, we focused on BOLD MRI responses to eyes opening and closing in complete darkness and the associated changes in the EEG's alpha frequency band (Berger's effect) as a possible approach to this problem. In awake subjects, BOLD MRI activation patterns were positively correlated to eyes opening and negatively to alpha power. In contrast, activation patterns of subjects with diminished wakefulness as determined by alpha band analysis were negatively correlated to eyes opening. We conclude that a control of the subjects' state of wakefulness must be of prime concern for functional MRI, especially for paradigms which allow for a free shift of vigilance.

Evaluation of cerebral perfusion deficit in stroke patients using new transcranial contrast imaging CPS technology--preliminary results

BACKGROUND AND PURPOSE

Contrast-enhanced transcranial duplex sonography can be used to examine cerebral perfusion. This technique, however, is still faced with methodological problems. The aim of the present study is to evaluate cerebral perfusion deficit after administration of the contrast agent SonoVue in acute stroke patients using new contrast imaging software.

METHODS

Ten subjects (6 male stroke patients and 4 healthy volunteers), were examined using transcranial duplex sonography (Acuson Sequoia 512 Ultrasound System) after a bolus injection of the contrast agent SonoVue. The transcranial examination was performed using transient response harmonic grey scale imaging with refill kinetics. The Sequoia ultrasonographic system was equipped with a new contrast harmonic imaging software "Cadence contrast pulse sequencing technology" (CPS). Triggered images with the mechanical index (MI) at 1.1 as well as continuous registration with MI at 0.28 were used for the evaluation of time intensity curves in several regions of interest. The sonographically imaged hypoperfused areas were compared with findings from MR imaging.

RESULTS

In all healthy volunteers, the contrast-enhanced signal could be recognized well in the ipsi- and also in the contralateral hemisphere up to the skull crown. In stroke patients, the perfusion deficit in the area of the MCA could be detected ipsilaterally in all subjects using triggered registration. Additionally, the area of MCA infarction could also be visualized in two patients using contralateral insonation. The low MI continuous imaging was successful in three patients. For all patients, the ischaemic region corresponded well in shape and size with the findings from MR imaging.

CONCLUSIONS

CPS enhances the possibility of perfusion-imaging in cerebral microcirculation and of perfusion-deficit-imaging in patients with cerebral ischaemia. Further studies with a larger number of patients should be carried out to improve this method.

Simultaneous recordings of visual evoked potentials and BOLD MRI activations in response to visual motion processing

Visual motion processing in humans was studied by simultaneous 32-channel electroencephalography (EEG) recordings of visual evoked potentials and BOLD MRI activations at 2.9 T. The paradigms compared three different random dot patterns (12 s duration) with stationary random dots (18 s) or with each other. The stimuli represented pattern reversal (500 ms switches between two stationary patterns), motion onset (200 ms of starfield motion followed by 1000 ms of stationary dots) and motion reversal (reversal of moving starfield directions every 1000 ms). Whereas motion-evoked visual potentials, and in particular the N2 component in occipito-temporal channels, were most prominent for motion onset, the most extended BOLD MRI activations and strongest signal changes in V5/MT+ were obtained in response to motion reversal. These apparently contradictory findings most likely reflect different physiological aspects of the neural activity associated with visual motion processing. For example, desynchronized activity of subpopulations of cortical neurons inside V5/MT+ is expected to attenuate visual evoked potentials in scalp recordings while continuously driving metabolic demands that lead to sustained BOLD MRI responses. The understanding of the physiological correlates and neural processes underlying either technique is fundamental to exploring fully the potential of combined EEG-MRI for studying human brain function at both high temporal and spatial resolution.