Elevated thrombin generation levels in the left atrial appendage in patients with atrial fibrillation

Introduction

Atrial Fibrillation (AF) is the most common sustained arrhythmia. Thrombus formation in the left atrial appendage (LAA) increases the risk for stroke and systemic embolism in AF patients. The proposed mechanisms for thrombus formation in the LAA are stasis, endothelial dysfunction and local hypercoagulability. The aim of this study was to compare thrombin generation potential in various heart chambers among AF patients.

Material and methods

A prospective cross-sectional study of 47 patients with AF undergoing pulmonary vein isolation (PVI). Blood samples from the femoral vein (FV), right atrium (RA), left atrium (LA) and LAA were collected during the PVI procedures. The Samples were collected before heparin administration. Thrombin generation was assessed by the calibrated automated thrombogram (CAT).

Results

A total of 47 patients (36.2% female, mean age 58.7±13, 59.6% with CHADS-VASc ≥2) were enrolled into the study. The mean endogenous thrombin potentials (ETP) were 1580±558, 1433±540, 1141±611 and 1487±760 in the FV, RA, LA and LAA, respectively (P<0.05). The mean thrombin peak heights were 244±124, 199±102, 139±94 and 195±129 in the FV, RA, LA and LAA, respectively (P<0.05).

A post-hoc pairwise comparison demonstrated elevated thrombin generation in the LAA compared to the LA (P=0.014). Furthermore, LA thrombin generation levels were significantly lower from the FV and RA (P<0.05).

Conclusion

In patients with AF, the LAA has increased thrombotic potential compared to the LA. These findings might explain why the LAA is more predisposed to thrombus formation than the LA.

Funding Acknowledgement

Type of funding sources: None.

POS1254 RISK FACTORS FOR SEVERE COVID-19 INFECTION AMONG PATIENTS WITH AUTOIMMUNE INFLAMMATORY RHEUMATIC DISEASES (AIRD) AND THE IMPACT OF VACCINATIONS - AN ISRAELI, MULTI-CENTER EXPERIENCE

Background

AIRD patients (pts) may be more susceptible to severe COVID19.

Objectives

To determine the risk factors for severe COVID19 and the effect of vaccinations among AIRD pts followed at dedicated rheumatology clinics.

Methods

At the onset of the pandemic, we established a national registry of AIRD pts, diagnosed with COVID19, based on voluntary reporting by the treating rheumatologist. 12 centers from Israel participated in the study. COVID19 was confirmed by a positive SARS CoV2 PCR. The indications for PCR testing were clinical symptoms or close contact with an infected person. Severe illness was defined by SpO2 <94% in room air, respiratory rate of >30 breaths/min, PaO2/FiO2 <300 mm Hg, or lung infiltrates >50% on imaging. The registry included demographic data, AIRD diagnosis and duration, visceral involvement, co-morbidities, immunomodulatory treatment, date of diagnosis and severity of COVID19 disease, management, complications, duration of hospitalization, the dates of the mRNA vaccinations, lab results and outcome. We analyzed data from 1.3.2020 to 30.11.2021

Results

During the study period we experienced 4 outbreaks of COVID19 infection. Initially social distancing, followed by a lockdown were imposed. The low number of cases led to relaxation of the measures. Two more severe outbreaks followed, which triggered 2 new lockdowns. The 3rd outbreak ended almost 2 months after vaccination started (BNT162b2 mRNA COVID19 vaccine). From March 1st 2020 to April 30, 2021, 298 AIRD pts (70.8% females, mean (SD) age 53.3(15.3)) with confirmed COVID19 infection were included. 43.3%(129) had visceral involvement due to the AIRD. 58.7%(175 pts) were on conventional synthetic disease modifying drugs (csDMARDs), 44.6% (133) on biologic/targeted DMARDs and 40% (120) on prednisone. Almost 2/3 of pts had at least one comorbidity.

In a multivariate logistic regression analysis age, AIRD with pulmonary involvement, diabetes and treatment with prednisone, mycophenolate mofetil or JAK inhibitors were associated with hospitalization. Older age, renal and vascular involvement due to the AIRD, and congestive heart failure were associated with higher mortality.

The 4th outbreak occurred 6 months after the introduction of vaccines, with spreading of the delta variant: 110 AIRD pts with COVID19 were recorded. Demographic data, clinical AIRD‘s characteristics, immunomodulatory treatment and comorbidities were similar to the previous outbreaks. However, during the 4th outbreak, the proportion of pts with severe COVID19, the hospitalization and mortality rate were significantly lower as compared to the first 3 outbreaks (15% vs 24%, 27% vs 53%, 6.7% vs 9.1%, respectively). Among COVID19 pts, 25% received a 3rd vaccine dose (booster), 56% contracted infection more than 5 months after the 2nd vaccine dose and 24% were unvaccinated. Most of the pts who received the booster contracted the disease within a week of vaccination. The odds ratio for hospitalization in vaccinated pts compared to unvaccinated was 0.11 (0.01 – 0.63 95% CI, p=0.041) in those vaccinated within the previous 1-5 months, and 0.38 (0.21-0.67 95% CI, p=0.001) in those vaccinated more than 6 months ago. 9 pts died, 5 were more than 6 months after the 2nd mRNA vaccine, 2 were unvaccinated and 1 patient received the booster on the same day of COVID19 diagnosis.

Conclusion

Before the vaccination campaign, the hospitalization and mortality rate in our cohort were similar to the data reported by other registries. COVID19 tends to be more severe, with increased mortality in patients with active AIIRD and visceral involvement (pulmonary, cardiac, renal), advanced age and co-morbidities. The delta outbreak occured 6 months after the implementation of vaccinations and was associated with significantly lower hospitalization and mortality rates, despite the increased aggressiveness of the variant. Vaccination of AIIRD pts with 3 doses of mRNA vaccines protects from severe COVID19 disease, hospitalization, and death.

Acknowledgements

Fadi Kharouf and Tali Eviatar had equal contribution

Disclosure of Interests

None declared

OP0177 IMMUNOGENICITY INDUCED BY TWO AND THREE DOSES OF THE BNT162B2 mRNA VACCINE IN PATIENTS WITH AUTOIMMUNE INFLAMMATORY RHEUMATIC DISEASES AND IMMUNOCOMPETENT CONTROLS: A LONGITUDINAL MULTI-CENTER STUDY

Background

Data on the kinetics of the immune response to SARS-CoV-2 vaccination in patients with autoimmune inflammatory rheumatic diseases (AIIRD) are limited.

Objectives

To evaluate the kinetics of the immune response induced by two and three doses of the BNT162b2 mRNA vaccine in adult patients with AIIRD and immunocompetent controls.

Methods

A prospective multicenter study investigated the antibody response to the BNT162b2 vaccine by serial measurement of serum anti-SARS-CoV-2 S1/S2 IgG titers at the following time points: 2-6 weeks (AIIRD n=720, controls n=122) and six months (AIIRD n=628, controls=116) after the second vaccine dose, and 2-6 weeks after the third vaccine dose (AIIRD n=169, controls n=45). A seropositive response was defined as a detectable anti-S1/S2 IgG titer ≥ 15 BAU/ml. T-cell immune response was evaluated in a sample of patients (n=28) and controls (n=9) by intracellular staining of S-stimulated CD4+ T-cells for TNFα and IFNγ production.

Results

The two-dose vaccine regimen induced a higher humoral response in controls compared to patients, as reflected by the post-vaccination seropositivity rates of 100% vs 84.72%, p<0.0001, and 96.55% vs 74.26%, p<0.0001 at 2-to-6 weeks and at 6 months, respectively. The decline of S1/S2 IgG titers within six months was similar in controls and patients. Following the 3rd vaccine, the seropositivity rate increased to 80.47% and 100% in AIIRD and control groups, p=0.0028, with a significantly higher increase of S1/S2 IgG titers in controls compared with AIIRD patients, 284.09±76.58 vs 219.39±151.55 BAU/ml, p=0.0016. At all-time points, S1/S2 IgG titers were significantly lower in AIIRD patients compared with controls (Figure 1).

We further investigated the impact of therapies on the vaccine‘s immunogenicity (Figure 1). Glucocorticoids (GC) were associated with a significantly lower seropositivity rate and lower S1/S2 IgG titers compared to controls at all time points. Monotherapy with methotrexate (MTX) was associated with a comparable to controls humoral response at all time points. Anti-cytokine biologics (TNFi, IL6i, IL17i) were associated with an initial high seropositivity rate, similar to controls, followed by a steeper decline at 6 months, 79.82% vs 96.55%, p=0.0001, and restoration of seropositivity after the 3rd vaccine dose in all patients. JAKi were associated with a mildly decreased seropositivity rate after the 2nd vaccine dose and similar to controls response after the 3rd vaccine dose. Abatacept was associated with a reduced immunogenicity after the 2nd vaccine dose, but was restored to 100% seropositivity after the 3rd vaccine dose. Rituximab (RTX) significantly blunted the humoral response at all time points, with a seropositivity rate of 42% after the 2nd vaccine dose, 29% at 6 months, and with increase to 40% after the 3rd vaccine dose. A third of the RTX-treated patients who were seronegative after two vaccine doses, seroconverted after the 3rd dose. The multivariate model for predicting the seropositive response to vaccination found that higher S1/S2 IgG titers after the 2nd vaccine dose was associated with a higher seropositivity rate following the 3rd vaccine dose, OR 1.026 (1.008-1.045), p=0.0027, and that treatment with RTX was associated with a 14.3-fold risk for a negative humoral response, p≤0.0001. Cellular immune response, evaluated mainly in RTX treated patients, was preserved prior to and after the 3rd vaccine dose and was similar to controls.

Conclusion

Over a six-month period, the two dose BNTb262 vaccination was associated with a similar extent of waning of the humoral immune response in AIIRD patients and controls. The 3rd vaccine dose restored the response in all controls and in patients treated with MTX monotherapy, anti-cytokine biologics, abatacept, and JAKi. Treatment with GC and RTX was associated with an impaired humoral response at all time points.

Acknowledgements

We would like to thank the statistician Mr Yishai Friedlander and Mr Yoram Neufeld for their valuable assistance.

Disclosure of Interests

None declared

POS1244 THE EFFECT OF SECUKINUMAB ON THE HUMORAL RESPONSE FOLLOWING TWO AND THREE DOSES OF THE BNT162b2 mRNA VACCINE IN PATIENTS WITH SPONDYLOARTHRITIS

Background

Data on the effect of secukinumab on the humoral response to the BNT162b2 mRNA vaccine are limited.

Objectives

We aimed to assess prospectively the humoral response to the BNT162b2 mRNA vaccine in patients with spondyloarthritis (SpA) treated with secukinumab in comparison to immunocompetent controls.

Methods

Patients with psoriatic arthritis (PsA) or ankylosing spondylitis (AS) treated with secukinumab for at least 3 months and immunocompetent controls were vaccinated with two-dose regimen of the BNT162b2 mRNA vaccine. Clinical and laboratory assessments were performed at 2-8 weeks [SpA: 37 on secukinumab, (median age 53% female), 122 controls (median age 53, 51% female)], and 6 months [SpA: 27 on secukinumab, 116 controls] after the second vaccine dose. A subgroup of patients (22 SpA on secukinumab, 45 controls) were evaluated after the third vaccine dose. The seropositive response was defined as a detectable S1/S2 IgG ≥15 binding antibody units (BAU)/ml.

Results

The two-dose vaccine regimen induced a similar immunogenic response in patients and controls reflected by the seropositivity rates of 100% in both groups. After six months, the rate of seropositivity remained as high as 96% in both secukinumab-treated patients and immunocompetent controls. The decline of S1/S2 IgG titer within six months was similar in controls and secukinumab-treated patients, -66.4 (95% CI {-70.9, -39.9}) and -55 BAU/ml (95% CI {-95.42, -36.87)). Following the third vaccine, the seropositivity rate increased to 100 % in both groups. At all-time points, S1/S2 IgG titers were similar in secukinumab treated patients and immunocompetent controls (Figure 1).

Figure 1.

Kinetics of an immunogenic response (S1/S2 IgG titer) to two and three doses of the BNT162b2 mRNA vaccine in SpA patients treated with secukinumab and immunocompetent controls.

Conclusion

SpA patients treated with secukinumab consistently demonstrated an adequate humoral response to the BNT162b2 mRNA vaccination similar to immunocompetent controls, both short-term and within six months after two vaccine doses and after the third vaccine dose.

Acknowledgements

We would like to thank Mr Yishai Friedlander and Mr Yoram Neufeld for their assistance.

Disclosure of Interests

Ori Elkayam: None declared, Tali Eviatar: None declared, Hagit Peleg: None declared, Daphna Paran: None declared, David Levartovsky: None declared, Ilana Kaufman: None declared, Adi Broyde: None declared, Ofir Elalouf: None declared, Ari Polachek: None declared, Joy Feld: None declared, Amir Haddad: None declared, Tal Gazitt: None declared, Muna Elias: None declared, Nizar Hijaze: None declared, Maher Aassi Employee of: Novartis Pharma AG, Erhard Quebe-Fehling Employee of: Novartis Pharma AG, Ivette Alarcon Employee of: Novartis Pharma AG, Sara Pel: None declared, Devy Zisman: None declared, Victoria Furer: None declared

Melanoma secretion of transforming growth factor-β2 leads to loss of epidermal AMBRA1 threatening epidermal integrity and facilitating tumour ulceration

BACKGROUND

For patients with early American Joint Committee on Cancer (AJCC)-stage melanoma the combined loss of the autophagy regulatory protein AMBRA1 and the terminal differentiation marker loricrin in the peritumoral epidermis is associated with a significantly increased risk of metastasis.

OBJECTIVES

The aim of the present study was to evaluate the potential contribution of melanoma paracrine transforming growth factor (TGF)-β signalling to the loss of AMBRA1 in the epidermis overlying the primary tumour and disruption of epidermal integrity.

METHODS

Immunohistochemistry was used to analyse AMBRA1 and TGF-β2 in a cohort of 109 AJCC all-stage melanomas, and TGF-β2 and claudin-1 in a cohort of 30 or 42 AJCC stage I melanomas, respectively, with known AMBRA1 and loricrin (AMLo) expression. Evidence of pre-ulceration was analysed in a cohort of 42 melanomas, with TGF-β2 signalling evaluated in primary keratinocytes.

RESULTS

Increased tumoral TGF-β2 was significantly associated with loss of peritumoral AMBRA1 (P < 0·05), ulceration (P < 0·001), AMLo high-risk status (P < 0·05) and metastasis (P < 0·01). TGF-β2 treatment of keratinocytes resulted in downregulation of AMBRA1, loricrin and claudin-1, while knockdown of AMBRA1 was associated with decreased expression of claudin-1 and increased proliferation of keratinocytes (P < 0·05). Importantly, we show loss of AMBRA1 in the peritumoral epidermis was associated with decreased claudin-1 expression (P < 0·05), parakeratosis (P < 0·01) and cleft formation in the dermoepidermal junction (P < 0·05).

CONCLUSIONS

Collectively, these data suggest a paracrine mechanism whereby TGF-β2 causes loss of AMBRA1 overlying high-risk AJCC early-stage melanomas and reduced epidermal integrity, thereby facilitating erosion of the epidermis and tumour ulceration.

POS0613 TOCILIZUMAB DECREASES ANGIOGENESIS IN RHEUMATOID ARTHRITIS THROUGH ITS REGULATORY EFFECT ON EMMPRIN/CD147

Background:

Angiogenesis is an important contributor to the development of Rheumatoid arthritis (RA). Tocilizumab (TCZ), an anti-IL-6 receptor antibody, is an immunosuppressant used in the treatment of RA patients, but its effects on angiogenesis and the molecular mechanisms regulating new blood vessel formation are not fully elucidated.

Objectives:

To evaluate the concentrations of pro- and anti-angiogenic factors in serum samples of RA patients, before and after the initiation of TCZ treatment and to explore in an in vitro co-culture system the mechanisms of TCZ action.

Methods:

We evaluated the concentrations of EMMPRIN, VEGF, MMP-9, IL-6, NGAL, endostatin and thrombospondin-1 (Tsp-1) using commercial ELISA kits from 40 RA patients, before and 4 months after the initiation of TCZ treatment. The levels of secreted EMMPRIN, VEGF MMP-9 and Tsp-1 were measured in an in vitro co-culture system of HT1080 fibroblasts and U937 monocytes with and without addition of anti-EMMPRIN blocking antibody. In the tube formation assay serum samples and supernatnats from the co-cultures were added to endothelial layer. Images were obtained after 6 hours of incubation and the number of closed lumens were counted in two separate fields. In the wound assay, supernatants from the co-cultures, with or without the addition of the anti-EMMPRIN antibody were added to the endothelial layer after scratching. The scratch site area was measured immediately and compared to the area after 24 hours of incubation to assess the distance of cell migration.

Results:

Study population included 40 RA patients, 33 (82.5%) females, mean age of 57.5±11.1 years, disease duration of 7.7±5.6 years, and 53.9% positive for rheumatoid factor initiating treatment with TCZ. In this patient cohort, 25/40 (62.5%) patients were classified as “responders” according to EULAR criteria.

Following 4 mounts of treatment, statistically significant reductions in the levels of EMMPRIN/CD147 (p=0.035), without significant changes in serum levels of MMP-9, VEGF, MMP-3 and MMP-7 and of the anti-angiogenetic factors Tsp-1 and endostatin were found. A statistically significant decrease in the ratio between the pro-angiogenic factor EMMPRIN and the anti-angiogenic factor Tsp-1 that was calculated for each patient 4 months after initiating TCZ was found(p=0.031). The decrease in angiogenesis was manifested by the reduced number of closed lumen tube-like structures formed by EaHy926 endothelial cell line after incubation with serum samples 4 months after initiation of TCZ, relative to the number of closed lumens formed prior to TCZ initiation (p=0.007). The ratio between EMMPRIN and Tsp-1 was significantly reduced in the responding patients versus non-responders (p=0.033), while the levels of VEGF, MMP-9, Tsp-1, and EMMPRIN were unchanged.

In vitro, the accumulation of the pro-angiogenic factors EMMRPIN, VEGF and MMP-9 in the supernatants was increased in the co-culture, while the accumulation of the anti-angiogenic factor Tsp-1 was decreased. When EMMPRIN was neutralized with a blocking antibody, supernatants derived from these co-cultures exhibited reduced migration, proliferation, and tube-like structure formation in functional assays.

Conclusion:

Our findings suggest an important role for EMMPRIN in mediating pro-angiogenic signals in RA patients, with EMMPRIN/Tsp-1 ratio serving as a marker of angiogenesis in RA. When administered to RA patients, TCZ in turn, exerts an anti-angiogenic effect through its regulation of EMMRPIN/CD147 levels.

Disclosure of Interests:

None declared

POS0974 IMPROVEMENT IN THE DIAGNOSTIC DELAY OF AXIAL SPONDYLOARTHRITIS, RESULTS FROM REAL WORLD DATA

Background:

Diagnostic delay is a major challenge in axial spondyloarthritis (axSpA) with an extended interval of 8-10 years in Europe and 14 years in the United States between symptom onset and disease diagnosis (1, 2).

Objectives:

To assess the delay in the diagnosis of axSpA over time in a real world axSpA cohort diagnosed in the last 3 decades and to evaluate factors associated with this delay.

Methods:

A cohort of axSpA patients was recruited from a national multicenter registry of inflammatory arthritis. This cohorts’ demographic, clinical and diagnostic variables were studied. The diagnostic delay was defined as the time interval between the year of first symptom and year of diagnosis. The mean and median diagnostic delay were calculated. A survival analysis was performed evaluating the association between the demographic, clinical and diagnostic variables on the diagnostic delay.

Results:

Of the 373 axSpA patients in the registry, 198 (47%) are men. Ankylosing spondylitis fulfilling New York criteria was diagnosed in 73% of the patients. HLA-B*27 positivity was found in 64% of patients. The majority of the patients (63%) reported symptom onset between the age of 21-45, 21% before the age of 21 and 16% after the age of 45. Nine percent were diagnosed before the age of 21, 28% between 21-30, 23% between 31-40, 21% between 41-50 and 18% after the age of 50. One hundred and ten patients were diagnosed before 2000, 133 between 2001-2009 and 130 between 2010-2020. The mean and median delay in diagnosis was 9.1, 6 (±8.4) years when diagnosed before 2000, 5, 4 (±4.1) years when diagnosed 2001-2009, and 2, 1 (±1.5) years when diagnosed 2010-2020, respectively (graph 1). The only variable which was found to be associated with a shorter delay was the interval between symptom onset and first rheumatology consult: HR of 5.86 (4.3-8, p<0.001) if the rheumatology visit was within the first year of symptoms, HR 3.5 (2.4-5, p<0.001) if assessed 2-3 years after symptom onset. Additionally, age <21 at symptom onset was associated with a shorter delay (p=0.005). Sex, type of axSpA (radiographic vs. non radiographic axSpA), level of education, and HLA-B*27 positivity were not associated with a delay in diagnosis.

Conclusion:

Delay in axSpA diagnosis has significantly improved in this real-world cohort during the last decade. The most significant factor associated with a faster diagnosis was the time of the first rheumatology consult relative to symptom onset. Increasing the awareness of disease manifestations and early referral to a rheumatology service can improve the diagnosis delay of axSpA.

References:

[1]Sorensen J, Hetland ML, all departments of rheumatology in D. Diagnostic delay in patients with rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis: results from the Danish nationwide DANBIO registry. Ann Rheum Dis. 2015;74(3):e12.

[2]Deodhar A, Mittal M, Reilly P, Bao Y, Manthena S, Anderson J, et al. Ankylosing spondylitis diagnosis in US patients with back pain: identifying providers involved and factors associated with rheumatology referral delay. Clin Rheumatol. 2016;35(7):1769-76.

Graph 1.

The improvement in the delay in diagnosis of axial spondyloarthropathy over the last 3 decades

Disclosure of Interests:

None declared.

POS0147 ANALYSIS OF VENOUS THROMBOEMBOLIC RISK AMONG PSORIATIC ARTHRITIS PATIENTS

Background:

Psoriatic arthritis (PsA) is a chronic, immune-mediated, systemic inflammatory arthritis associated with comorbidities including metabolic syndrome, cardiovascular risk factors and cardiovascular disease (CVD).

Objectives:

To evaluate the prevalence of venous thromboembolism (VTE) in a PsA patient cohort using a large health care provider database.

Methods:

A large health care provider database serving 4.7 million healthcare subscribers was interrogated for an adult patient cohort who were newly diagnosed with PsA between January 2005 (start date) and 31 December 2018 with date of diagnosis considered the index date. A risk set was employed to randomly select 4 controls without PsA as a comparator group to the PsA cohort matched by age, sex, ethnic group, and index date. Both groups were followed from the index date until the first occurrence of VTE event, death, or end of follow-up 31 December 2019, whichever came first. Marginal model with robust covariant estimate counting for the matching was used to estimate the crude and adjusted hazard ratio (HR) for the association between PsA and VTE. Within the group of PSA patients, Cox proportional hazard regression models was used to calculate the risk of having VTE given demographic variables, SES, smoking, selected comorbidities, and conventional vs biologic disease modifying anti-rheumatic drugs (c/bDMARD). Continuous variables were summarized with mean ± standard deviation, and categorical variables were presented as numbers and proportions. All tests were 2-sided; p values of < = 0.05 were considered statistically significant. All data were analyzed using SPSS, 24 (IBM SPSS Statistics for Windows, version 24.0, 2016, Armonk, NY) and SAS, 9.4 (SAS institute Inc, Cary, NC).

Results:

The PsA cohort consisted of 5,275 patients, 53.2% females with mean age of 51.66 ±15.41. The control group consisted of 21,011 subjects matched for age and sex. In relation to the control group, the PsA cohort had a higher SES (25.1% vs 23.4%, p<0.0001), higher tobacco use (42.2% vs.39.6% p<0.0001) and obesity (33.5% vs 25.8%, p<0.0001). The study group had a statistically significant higher incidence of diabetes (33.8% vs 26.2%, p<0.0001), IHD (10.3% vs 8.6%, p<0.0001), CHF (2.2% vs 1.6%, p=0.004), hypertension (30.1% vs 26.2%, p<0.0001), CVA/TIA (4.6% vs 3.9%, p=0.024) and vascular disease (3.7% vs 3.0%, p=0.005). There were 62 patients (1.2%) diagnosed with VTE in the PsA group as opposed to 176 patients (0.8%) in the control group (p=0.023, HR=1.397, CI 1.05-1.87). The mean age of patients diagnosed with VTE was higher in the PsA group relative to controls (64.90± 13.20 vs 51.54 ± 15.41, respectively, p<0.0001), with higher age, BMI>30, cancer, IHD, vascular disease, and previous VTE found to be associated with VTE in the PsA group relative to controls in both univariate and multivariate analyses. The higher prevalence of VTE in PsA patients relative to controls did not remain statistically significant in multivariate analysis following adjustment for risk factors. Within the PsA group, patients with VTE were more often of older age and with past history of VTE. Both cDMARD and bDMARD were not associated with increased risk of VTE among PsA patients.

Conclusion:

The prevalence of VTE was higher in PsA group compared to the general population, but after adjustment for comorbidities and risk factors, it no longer remained statistically significant. Among PsA patients, age and previous history of VTE were associated with increased risk of VTE. Addressing VTE risk in the management of patients with PsA is recommended especially in the era of Janus kinase inhibitors.

Disclosure of Interests:

None declared

LB0003 IMMUNOGENICITY AND SAFETY OF THE BNT162b2 mRNA COVID-19 VACCINE IN ADULT PATIENTS WITH AUTOIMMUNE INFLAMMATORY RHEUMATIC DISEASES AND GENERAL POPULATION: A MULTICENTER STUDY

Background:

Vaccination represents a cornerstone in mastering the COVID-19 pandemic. Data on immunogenicity, efficacy, and safety of the novel BNT162b2 mRNA vaccine in patients with autoimmune inflammatory rheumatic diseases (AIIRD) are limited.

Objectives:

To investigate the immunogenicity, efficacy, and safety of the BNT162b2 mRNA vaccine in patients with AIIRD compared to the general population.

Methods:

A prospective multicenter study investigated immunogenicity, efficacy, and safety of the two-dose regimen BNT162b2 mRNA vaccine in adult patients with AIIRD including rheumatoid arthritis (RA), psoriatic arthritis (PsA), axial spondyloarthropathy (axSpA), systemic lupus erythematosus (SLE), connective tissues diseases (CTD), systemic vasculitides, and idiopathic inflammatory myositis (IIM), compared to control subjects without rheumatic diseases or immunosuppressive therapies. Serum IgG antibody levels against SARS-CoV-2 spike S1/S2 proteins were measured 2 - 6 weeks after the second vaccine dose. Seropositivity was defined as IgG ≥15 binding antibody units (BAU)/ml. Post-vaccination efficacy defined as post-vaccination COVID-19 infection and safety were assessed. Pre- and post- vaccination disease activity indices were assessed as appropriate for each disease.

Results:

A total of 686 AIIRD patients and 121 controls participated into the study. AIIRD patients were significantly older than controls, mean age±SD 56.76±14.88 vs 50.76±14.68, respectively, p<0.0001. A total of 95.2% (n=653) AIIRD patients were treated with immunomodulatory medications.

The seropositivity rate was 86% (n=590) in patients with AIIRD compared to 100% in controls (p <0.0001) The level of the S1/S2 antibodies was significantly reduced in AIIRD patients compared to controls (mean± SD 132.9±91.7 vs 218.6±82.06, P<0.0001). In patients with PsA, AxSpA, SLE, and LVV, the seropositive rate was above 90%. In RA, the seropositive rate was 82.1% and the lowest seropositive rate (<40%) was observed in patients with AAV and IIM.

Anti-CD20 significantly impaired the vaccine’s immunogenicity, with the lowest seropositivity rate of 39%. The use of GC, mycophenolate mofetil (MMF), and abatacept was associated with a significantly lower rate of seropositivity (Figure 1). MTX significantly reduced the seropositivity in patients treated with MTX monotherapy and in combinations with other treatments (92% and 84%, respectively), although at a lesser magnitude than anti-CD20, MMF, and abatacept. More than 97% of patients treated with anti-cytokine therapies including TNFi, interleukin-17 and interleukin-6 inhibitors had an appropriate immunogenic response when used as monotherapy. The combination of TNFi with MTX significantly reduced the rate of seropositivity to 93%, p=0.04. Age over 65 years, a diagnosis of RA, IIM, ANCA-associated vascilitis, and treatment with GC, MMF, anti-CD20, and abatacept were associated with a reduced likelihood of seropositivity.

Figure 1.

Seropositivity rate by immunosuppressive treatment.

There were no post-vaccination symptomatic cases of COVID-19 among AIIRD patients and one mild case in the control group. Major adverse events in AIIRD patients included death (n=2) several weeks after the second vaccine dose, non-disseminated herpes zoster (n=6), uveitis (n=2), and pericarditis (n=1). Post-vaccination disease activity remained stable in the majority of patients.

Conclusion:

Vaccination with the BNTb262 vaccine resulted in an adequate immunogenic response with an acceptable safety profile in the majority of patients with AIIRD. Treatment with GC, rituximab, MMF, and abatacept may impair BNT162b2-induced immunogenicity. Postponing administration of rituximab, when clinically feasible, seems to be reasonable to improve vaccine-induced immunogenicity. Holding treatment with abatacept and MMF may be considered on an individual basis.

Disclosure of Interests:

None declared

Thrombin generation's role in predicting coronary disease severity

BACKGROUND

Thrombin, a key enzyme of the clotting system, is involved in thrombus formation, platelet activation, and atherosclerosis, thereby possessing a central role in the pathogenesis of ischemic heart disease. Studies have shown an association between thrombin generation (TG) and cardiovascular morbidity and mortality, but results have been equivocal. Our aim was to study the predictive ability of TG assay in evaluating coronary stenosis severity.

METHODS

In this prospective study we recruited patients with acute coronary syndrome (ACS) or acute chest pain (without evidence of myocardial injury) planned for coronary angiography. Thrombin generation was evaluated by Calibrated Automated Thrombogram (CAT) prior to angiography. Primary end points were significant coronary stenosis and the Syntax I score evaluated by coronary angiography.

RESULTS

From April 2018 through September 2019, we recruited 128 patients. In the primary analysis there was no significant association between TG and significant coronary stenosis nor between TG and syntax I score, however, there was a positive correlation between peak height and troponin peak (Spearman correlation coefficient 0.194, P-value = 0.035). In sub-group analysis, the chest pain group bare no association between TG and coronary stenosis. In unstable angina group there was an association between peak height and significant coronary stenosis (P-value = 0.029), and in non ST-elevation myocardial infarction group, TG values possessed a relatively good predictive ability of significant coronary stenosis (area under the receiver operating characteristic curve of ~65%) and a positive correlation between both lag time and ttpeak with the syntax I score was noticed (Spearman correlation coefficient 0.31, P-value = 0.099 and Spearman correlation coefficient 0.37, P-value = 0.045 respectively).

CONCLUSION

In patients with acute chest pain, TG values, evaluated by CAT, do not predict severity of coronary stenosis, nor do they possess prognostic value. Yet, in ACS patients, TG may have the ability to predict coronary disease severity.

Low venous thromboembolism incidence in high risk medical patients in an Israeli hospital. Can risk assessment be extrapolated to different populations?

BACKGROUND

Guidelines recommend venous thromboembolism (VTE) prophylaxis in hospitalized medical patients with Padua prediction score (PPS) ≥4 points. This recommendation is based on the high risk of symptomatic VTE observed among these patients in the Italian PPS derivation study, and the fivefold risk reduction with VTE-prophylaxis. This study aims to assess the incidence of VTE in high risk medical patients in a medium sized hospital in Israel.

METHOD

In this retrospective cohort study, data was collected of all medical patients hospitalized between January and June 2014. Patients were classified into low and high risk groups according to their PPS score, and according to whether they received anticoagulant thromboprophylaxis for VTE. Patients were further randomly selected to compare high risk patients that did or did not receive anticoagulant thromboprophylaxis. We further compared VTE incidence in high and low risk patients not treated with thromboprophylaxis. A search was conducted for diagnoses of venous thromboembolism and death during hospitalization and the following 90 days.

RESULTS

568 high risk patients (PPS ≥4 points) were included, 284 treated with prophylactic anticoagulation and 284 not. There were no VTE events in either group. There was no difference in mortality. A total of 642 non anticoagulated patients were randomly selected, 474 low risk and 168 high risk. There were no VTE events in either group.

CONCLUSIONS

The risk of VTE appears to be very low in our study, suggesting that among medical patients with PPS ≥4, the risk of VTE may differ dramatically between populations.

Appetite and ghrelin levels in iron deficiency anemia and the effect of parenteral iron therapy: A longitudinal study

BACKGROUND

Iron deficiency anemia (IDA) is associated with decreased appetite. The ghrelin hormone is one of the major regulators of appetite.

OBJECTIVES

To evaluate appetite and ghrelin levels in patients with IDA, and to investigate the change in appetite and ghrelin following intravenous iron therapy.

METHODS

A total of 56 IDA patients and 51 controls were included in the study. Both appetite and ghrelin were assessed at baseline and following intravenous iron therapy. These were assessed at corresponding time intervals in the control group. Appetite was assessed by the SNAQ score (Simplified Nutritional Appetite Questionnaire) and fasting ghrelin levels were assessed by acylated ghrelin (AG), unacylated ghrelin (UAG) and their respective ratio AG/UAG.

RESULTS

IDA patients had significantly lower SNAQ scores, yet higher AG levels and higher AG/UAG ratios compared to healthy controls; the mean SNAQ scores were 12.56 ± 3.45 and 16.1 ± 2, respectively (P<0.01); the median AG levels were 57.5 pg/ml and 43 pg/ml respectively (P = 0.007); and the median AG/UAG ratios were 0.48 and 0.25 respectively (P = 0.04). On multivariate linear regression analysis, IDA remained independently associated with decreased SNAQ score (β = -0.524, P<0.001) and increased acylated ghrelin (β = 0.289, P = 0.013). After IDA was treated, SNAQ scores increased significantly by a mean of 2 points. AG and AG/UAG ratios decreased significantly by a mean of -18.44 pg/ml and -0.2 respectively. The control group showed no significant change in SNAQ scores or ghrelin at corresponding time intervals.

CONCLUSIONS

IDA patients have a reduced appetite and paradoxically elevated ghrelin hormone activity compared to healthy controls. Treating IDA enhances appetite and lowers ghrelin levels. Future studies are needed to explore the mechanism of this paradoxical ghrelin activity.

Author Correction: Phenological shifts alter the seasonal structure of pollinator assemblages in Europe

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Phenological shifts alter the seasonal structure of pollinator assemblages in Europe

Pollinators play an important role in terrestrial ecosystems by providing key ecosystem functions and services to wild plants and crops, respectively. The sustainable provision of such ecosystem functions and services requires diverse pollinator communities over the seasons. Despite evidence that climate warming shifts pollinator phenology, a general assessment of these shifts and their consequences on pollinator assemblages is still lacking. By analysing phenological shifts of over 2,000 species, we show that, on average, the mean flight date of European pollinators shifted to be 6 d earlier over the last 60 yr, while their flight period length decreased by 2 d. Our analysis further reveals that these shifts have probably altered the seasonal distribution of pollination function and services by decreasing the overlap among pollinators' phenologies within European assemblages, except in the most northeastern part of Europe. Such changes are expected to decrease the functional redundancy and complementarity of pollinator assemblages and, therefore, might alter the performance of pollination function and services and their robustness to ongoing pollinator extinctions.

Tumor Lysis Syndrome in Chronic Lymphocytic Leukemia: A Rare Case Report from Nephrology

Patient: Female, 89

Final Diagnosis: Tumor lysis syndrome (TLS)

Symptoms: Dyspnea

Medication: Steriods

Clinical Procedure: HD

Specialty: Nephrology

Calibrated Automated Thrombogram During Pregnancy in Unexplained Recurrent Miscarriages: A Pilot Study

BACKGROUND

Recurrent miscarriages are associated with a high prevalence of thrombophilia. Use of a calibrated automated thrombogram (CAT) can serve as a universal test for thrombophilia.

OBJECTIVES

To examine whether thrombin generation measured by CAT is elevated during the first trimester in women with unexplained recurrent miscarriages.

METHODS

This study comprised 25 pregnant women with recurrent pregnancy loss referred for thrombophilia screening and treated with low-molecular-weight heparin (LMWH). Thrombin generation parameters were measured in women who had miscarriages or live births and who were diagnosed as positive or negative for thrombophilia.

RESULTS

Of the pregnancies, 76% resulted in live birth and 24% ended in miscarriages. Among the women, 76% were positive for thrombophilia. Thrombin generation parameters between pregnancies that ended in miscarriage compared to live births were not significantly different, and CAT parameters failed to predict pregnancy outcome. Although the CAT parameters demonstrated a trend toward a hypercoagulable state in women with thrombophilia, there was no statistical significance (P > 0.05).

CONCLUSIONS

Women with unexplained pregnancy loss demonstrated similar thrombin generation in the first trimester, regardless of the pregnancy outcome. CAT parameters failed to predict pregnancy outcome in women with recurrent unexplained pregnancy loss. Our results should be interpreted with caution due to the small number of participants.

Epidermal autophagy and beclin 1 regulator 1 and loricrin: a paradigm shift in the prognostication and stratification of the American Joint Committee on Cancer stage I melanomas

BACKGROUND

The updated American Joint Committee on Cancer (AJCC) staging criteria for melanoma remain unable to identify high-risk stage I tumour subsets.

OBJECTIVES

To determine the utility of epidermal autophagy and beclin 1 regulator 1 (AMBRA1)/loricrin (AMLo) expression as a prognostic biomarker for AJCC stage I cutaneous melanoma.

METHODS

Peritumoral AMBRA1 expression was evaluated in a retrospective discovery cohort of 76 AJCC stage I melanomas. AMLo expression was correlated with clinical outcomes up to 12 years in two independent powered, retrospective validation and qualification cohorts comprising 379 AJCC stage I melanomas.

RESULTS

Decreased AMBRA1 expression in the epidermis overlying primary melanomas in a discovery cohort of 76 AJCC stage I tumours was associated with a 7-year disease-free survival (DFS) rate of 81·5% vs. 100% survival with maintained AMBRA1 (P < 0·081). Following an immunohistochemistry protocol for semi-quantitative analysis of AMLo, analysis was undertaken in validation (n = 218) and qualification cohorts (n = 161) of AJCC stage I melanomas. Combined cohort analysis revealed a DFS rate of 98·3% in the AMLo low-risk group (n = 239) vs. 85·4% in the AMLo high-risk cohort (n = 140; P < 0·001). Subcohort multivariate analysis revealed that an AMLo hazard ratio (HR) of 4·04 [95% confidence interval (CI) 1·69-9·66; P = 0·002] is a stronger predictor of DFS than Breslow depth (HR 2·97, 95% CI 0·93-9·56; P = 0·068) in stage IB patients.

CONCLUSIONS

Loss of AMLo expression in the epidermis overlying primary AJCC stage I melanomas identifies high-risk tumour subsets independently of Breslow depth. What's already known about this topic? There is an unmet clinical need for biomarkers of early-stage melanoma. Autophagy and beclin 1 regulator 1 (AMBRA1) is a proautophagy regulatory protein with known roles in cell proliferation and differentiation, and is a known tumour suppressor. Loricrin is a marker of epidermal terminal differentiation. What does this study add? AMBRA1 has a functional role in keratinocyte/epidermal proliferation and differentiation. The combined decrease/loss of peritumoral AMBRA1 and loricrin is associated with a significantly increased risk of metastatic spread in American Joint Committee on Cancer (AJCC) stage I tumours vs. melanomas, in which peritumoral AMBRA1 and loricrin are maintained, independently of Breslow depth. What is the translational message? The integration of peritumoral epidermal AMBRA1/loricrin biomarker expression into melanoma care guidelines will facilitate more accurate, personalized risk stratification for patients with AJCC stage I melanomas, thereby facilitating stratification for appropriate follow-up and informing postdiagnostic investigations, including sentinel lymph node biopsy, ultimately resulting in improved disease outcomes and rationalization of healthcare costs.

Predictive capacity of prodromal symptoms in first-episode psychosis of recent onset

BACKGROUND

Both the nature and number of a wide range of prodromal symptoms have been related to the severity and type of psychopathology in the psychotic phase. However, at present there is an incomplete picture focused mainly on the positive pre-psychotic dimension.

AIM

To characterize the prodromal phase retrospectively, examining the number and nature of prodromal symptoms as well as their relationship with psychopathology at the onset of first-episode psychosis.

METHODS

Retrospective study of 79 patients experiencing a first-episode psychosis of less than 1 year from the onset of full-blown psychosis. All patients were evaluated with a comprehensive battery of instruments including socio-demographic and clinical questionnaire, IRAOS interview, PANSS, stressful life events scale (PERI) and WAIS/WISC (vocabulary subtest). Bivariate associations and multiple regression analysis were performed.

RESULTS

Regression models revealed that several prodromal dimensions of IRAOS (delusions, affect, language, behaviour and non-hallucinatory disturbances of perception) predicted the onset of psychosis, with positive (22.4% of the variance) and disorganized (25.6% of the variance) dimensions being the most widely explained.

CONCLUSION

In addition to attenuated positive symptoms, other symptoms such as affective, behavioural and language disturbances should also be considered in the definitions criteria of at-high-risk people.

Enhanced thrombin generation in patients with arterial hypertension

BACKGROUND

Arterial hypertension is associated with greater risk of cardiovascular diseases and thrombotic complications, suggesting that hypertension is a prothrombotic state.

OBJECTIVES

To investigate the relationship between arterial hypertension and thrombin generation, and between blood pressure level and thrombin generation in hypertensive patients.

METHODS

A total of 165 hypertensive patients and 47 healthy adults controls were include in the study. Thrombin generation was assessed in both groups by the Calibrated Automated Thrombogram (CAT) method. Ambulatory blood pressure monitoring (ABPM) was also performed for all patients in the hypertensive group.

RESULTS

Hypertensive patients had significantly higher levels of ETP and peak heights compared to healthy controls; means of ETP 1720.6 ± 267 and 1544.7 ± 302, respectively (P < 0.001) and means of peak height were 297.26 ± 48 and, 273 ± 53, respectively (P < 0.001). On multivariate linear regression analysis, hypertension remained independently associated with increased ETP (β = 0.185, P = 0.047). Analysis restricted to the hypertensive group with ABPM measurement showed statistically significant correlations between all measures of diastolic blood pressure (DBP) and ETP, and multivariate analysis showed that awake DBP was significantly associated with ETP (β = 0.194 for each 1-mm Hg increase in awake DBP, P = 0.012). Furthermore, hypertensive patients with cardiovascular complications had statistically elevated levels of peak height compared to hypertensive patients without cardiovascular complications.

CONCLUSIONS

Hypertensive patients possess enhanced thrombin generation compared healthy controls. Diastolic blood pressure level is independently correlated with increased thrombin generation in hypertensive patients. These findings suggest that arterial hypertension is a prothrombotic state.

Portal Vein Thrombosis and Thrombocytopenia in Eosinophilic Granulomatosis with Polyangiitis: A Paradox?

A 36-year-old woman with eosinophilic granulomatosis with polyangiitis (EGPA) presented with necrotic skin lesions and pulmonary infiltrates. There was eosinophilic vasculitis on skin biopsy, and substantial tissue eosinophilia in her bone marrow. She had unexplained worsening thrombocytopenia, which prompted a thrombophilia work-up. However, abnormalities in liver enzymes led to the extraordinary finding of portal vein thrombosis. Thrombocytopenia resolved with treatment with low molecular weight heparin. This case highlights the risk of hypercoagulability in eosinophilia specifically, and in EGPA. We suggest that thrombosis should be ruled out in all cases of EGPA.

Morphology in Multilayer Blown Films of Polypropylene and Ethylene-Octene Copolymer Blends

In this work the microstructure of multilayer blown films consisting of a core layer placed between two external ones is studied. The core layer is a blend with 70 ° (w/w) of a homopolypropylene PP and 30 ° of a metallocene-catalyzed ethylene-octene copolymer mEOC (LLDPE or VLDPE), whereas the external symmetrical layers are composed of LLDPE or they have the same composition as the core layer. The PP and PE crystalline phases formed during the film blowing were investigated by thermal analysis, mechanical properties, TEM morphology and X-ray diffraction pole figures. These films successfully combine the high mechanical strength of PP with the quasi-isotropic behavior of blown PE. Multilayer film containing PP/mEOC blends, particularly blends of PP70/LLDPE30, show better balanced tensile properties when compared at crossed directions. The presence of VLDPE in the blends shifts downwards the melting and crystallization temperatures and crystallinity of PP. X-Ray pole figures suggest the occurrence of epitaxial crystallization of the PE phase upon the PP crystals in these PP/mEOC blend films.

Efecto de los cultivos autóctonos en la producción de Paio, un embutido curado tradicional portugués

En los países mediterráneos, como Portugal, los embutidos curados tradicionales son muy apreciados. A menudo se siguen fabricando en pequeñas unidades de procesamiento, de acuerdo con los procedimientos tradicionales. Los objetivos del presente estudio fueron evaluar el efecto de diferentes cultivos iniciadores y su concentración óptima, para reducir la carga microbiana y las aminas biogénicas en productos finales, con el objetivo de mejorar la seguridad de los embutidos sin deteriorar la aceptación sensorial. pH, aw, perfil microbiológico, aminas biogénicas, análisis del perfil de color y textura fueron evaluados. Las cepas y las concentraciones a utilizar, se seleccionaron en base a resultados previos: Staphylococcus xylosus, Lactobacillus sakei y una cepa de levadura a una concentración de 106 ufc / g de masa de carne cada una, se añadió 0,25% de dextrosa. Siempre se utilizó un lote control sin cultivos iniciadores. Los valores de aw fueron menores en los embutidos inoculados. En general, los valores de pH fueron ligeramente superiores en los embutidos inoculados. El tratamiento con L. sakei solo fue el más efectivo en la reducción del nivel de contaminación con L. monocytogenes, sin embargo este efecto parece perderse en cultivos mixtas. La inoculación, disminuyó generalmente el contenido de putrescina, de cadaverina y de tiramina. La inoculación de levadura parece contribuir al color más oscuro de los Paios. Con respecto a la textura, el Paio control demostró valores más altos de la dureza.

Adición de vinagre para prolongar la vida útil de la cabeça de xara

Cabeça de xara es un producto de carne listos para comer, cuya producción es muy característica en el Alentejo, una región de Portugal. Es una galantina que generalmente se moldea en forma de paralelepípedo. Se elabora con varias carnes obtenidas de la raza porcina Alentejana y criada en la misma región, cabezas de cerdo deshuesadas, lengua y tejido conectivo, a la que se le añade una serie de condimentos como sal, perejil, vino y pimienta. Este trabajo se pretende poner a prueba la viabilidad de añadir vinagre con el fin de aumentar la vida útil de la cabeça de xara, mediante la reducción de la microbiota contaminante responsables del deterioro, así como el control del patógeno Listeria monocytogenes. Tres lotes independientes fueron producidos y con composición proximal parecida, se evaluó pH, aw, parámetros microbiológicos y contenido de aminas biogénicas. El análisis sensorial se realizó también durante todo el período de almacenamiento. No se encontraron diferencias significativas entre las muestras control y vinagre en cuanto a la composición proximal de cabeça de xara. Como era de esperar, el pH fue menor en las muestras con vinagre, sin embargo se observaron diferencias en aw entre los dos tratamientos. L. monocytogenes estuvo presente desde el primer mes sólo en un lote, en el tratamiento control. Sin embargo, es inhibida por la adición de vinagre de vino hasta el tercer mes de almacenamiento, donde L. monocytogenes está presente pero por debajo del límite establecido en el Reglamento 2073/2005. La presencia de vinagre redujo significativamente el contenido de aminas biógenicas, en particular cadaverina, putrescina y tiramina, durante todo el período de almacenamiento. En cuanto a la evaluación sensorial, el sabor a vinagre fue evaluado por los panelistas de manera negativa.

Widespread hybridization within mound-building wood ants in Southern Finland results in cytonuclear mismatches and potential for sex-specific hybrid breakdown

Hybridization and gene flow between diverging lineages are increasingly recognized as common evolutionary processes, and their consequences can vary from hybrid breakdown to adaptive introgression. We have previously found a population of wood ant hybrids between Formica aquilonia and F. polyctena that shows antagonistic effects of hybridization: females with introgressed alleles show hybrid vigour, whereas males with the same alleles show hybrid breakdown. Here, we investigate whether hybridization is a general phenomenon in this species pair and analyse 647 worker samples from 16 localities in Finland using microsatellite markers and a 1200-bp mitochondrial sequence. Our results show that 27 sampled nests contained parental-like gene pools (six putative F. polyctena and 21 putative F. aquilonia) and all remaining nests (69), from nine localities, contained hybrids of varying degrees. Patterns of genetic variation suggest these hybrids arise from several hybridization events or, instead, have backcrossed to the parental gene pools to varying extents. In contrast to expectations, the mitochondrial haplotypes of the parental species were not randomly distributed among the hybrids. Instead, nests that were closer to parental-like F. aquilonia for nuclear markers preferentially had F. polyctena's mitochondria and vice versa. This systematic pattern suggests there may be underlying selection favouring cytonuclear mismatch and hybridization. We also found a new hybrid locality with strong genetic differences between the sexes similar to those predicted under antagonistic selection on male and female hybrids. Further studies are needed to determine the selective forces that act on male and female genomes in these newly discovered hybrids.

[Decontamination of organophosphorus compounds: Towards new alternatives]

Organophosphorus coumpounds (OP) are toxic chemicals mainly used for agricultural purpose such as insecticides and were also developed and used as warfare nerve agents. OP are inhibitors of acetylcholinesterase, a key enzyme involved in the regulation of the central nervous system. Chemical, physical and biological approaches have been considered to decontaminate OP. This review summarizes the current and emerging strategies that are investigated to tackle this issue with a special emphasis on enzymatic remediation methods. During the last decade, many studies have been dedicated to the development of biocatalysts for OP removal. Among these, recent reports have pointed out the promising enzyme SsoPox isolated from the archaea Sulfolobus solfataricus. Considering both its intrinsic stability and activity, this hyperthermostable enzyme is highly appealing for the decontamination of OP.

The Prevalence of Thrombophilia in Women With Recurrent Fetal Loss and Outcome of Anticoagulation Therapy for the Prevention of Miscarriages

OBJECTIVE

To estimate the prevalence of thrombophilia in women with recurrent miscarriages and to assess the effect of antithrombotic therapy.

DESIGN

A retrospective cohort study between the years 2004 and 2010.

SETTING

A hypercoagulation community clinic in northern Israel.

PATIENTS

Four hundred ninety pregnant women referred for thrombophilia screening.

MAIN OUTCOME MEASURES

Screening results for thrombophilia and antithrombotic treatment with enoxaparin, aspirin, or both and pregnancy outcomes.

RESULTS

The most common thrombophilia in our study group was factor V Leiden mutation with a prevalence of 20.9% followed by protein S deficiency with a prevalence of 19%. Live birth rate was higher in the group of women who received enoxaparin regardless of whether a specific thrombophilia could be found. This finding was more pronounced in women who had ≥4 miscarriages.

CONCLUSION

The prevalence of thrombophilia was higher in our study group than in the general population. Furthermore, treatment with enoxaparin might improve the rate of live births in women with or without evidence of thrombophilia, especially in women with ≥4 miscarriages.

[Enzymes for disrupting bacterial communication, an alternative to antibiotics?]

Quorum sensing (QS) is used by bacteria to communicate and synchronize their actions according to the cell density. In this way, they produce and secrete in the surrounding environment small molecules dubbed autoinducers (AIs) that regulate the expression of certain genes. The phenotypic traits regulated by QS are diverse and include pathogenicity, biofilm formation or resistance to anti-microbial treatments. The strategy, aiming at disrupting QS, known as quorum quenching (QQ), has emerged to counteract bacterial virulence and involves QS-inhibitors (QSI) or QQ-enzymes degrading AIs. Differently from antibiotics, QQ aims at blocking cell signaling and does not alter bacterial survival. This considerably decreases the selection pressure as compared to bactericide treatments and may reduce the occurrence of resistance mechanisms. QQ-enzymes are particularly appealing as they may disrupt molecular QS-signal without entering the cell and in a catalytic way. This review covers several aspects of QQ-based medical applications and the potential subsequent emergence of resistance is discussed.

Role of antibiotics for treatment of inflammatory bowel disease

Inflammatory bowel disease is thought to be caused by an aberrant immune response to gut bacteria in a genetically susceptible host. The gut microbiota plays an important role in the pathogenesis and complications of the two main inflammatory bowel diseases: Crohn’s disease (CD) and ulcerative colitis. Alterations in gut microbiota, and specifically reduced intestinal microbial diversity, have been found to be associated with chronic gut inflammation in these disorders. Specific bacterial pathogens, such as virulent Escherichia coli strains, Bacteroides spp, and Mycobacterium avium subspecies paratuberculosis, have been linked to the pathogenesis of inflammatory bowel disease. Antibiotics may influence the course of these diseases by decreasing concentrations of bacteria in the gut lumen and altering the composition of intestinal microbiota. Different antibiotics, including ciprofloxacin, metronidazole, the combination of both, rifaximin, and anti-tuberculous regimens have been evaluated in clinical trials for the treatment of inflammatory bowel disease. For the treatment of active luminal CD, antibiotics may have a modest effect in decreasing disease activity and achieving remission, and are more effective in patients with disease involving the colon. Rifamixin, a non absorbable rifamycin has shown promising results. Treatment of suppurative complications of CD such as abscesses and fistulas, includes drainage and antibiotic therapy, most often ciprofloxacin, metronidazole, or a combination of both. Antibiotics might also play a role in maintenance of remission and prevention of post operative recurrence of CD. Data is more sparse for ulcerative colitis, and mostly consists of small trials evaluating ciprofloxacin, metronidazole and rifaximin. Most trials did not show a benefit for the treatment of active ulcerative colitis with antibiotics, though 2 meta-analyses concluded that antibiotic therapy is associated with a modest improvement in clinical symptoms. Antibiotics show a clinical benefit when used for the treatment of pouchitis. The downsides of antibiotic treatment, especially with recurrent or prolonged courses such as used in inflammatory bowel disease, are significant side effects that often cause intolerance to treatment, Clostridium dificile infection, and increasing antibiotic resistance. More studies are needed to define the exact role of antibiotics in inflammatory bowel diseases.

Pattern of Blood Pressure Response in Patients With Severe Asymptomatic Hypertension Treated in the Emergency Department

Severe asymptomatic hypertension (SAH) is a common cause of emergency department (ED) visits. Despite recommendations against using short-acting blood pressure (BP)-lowering drugs in the ED, it is still a common practice. The authors characterized BP response in the ED utilizing 24-hour ambulatory BP monitoring (ABPM). Patients with SAH who were not admitted to the hospital were recruited. All patients underwent 24-hour ABPM. A total of 21 patients (14 females) with a mean age of 58±16 years were studied. BP decreased from 199±16/101±17 mm Hg to 154±34/83±23 mm Hg after 5 hours but then rose to 174±25/94±17 mm Hg after 19 hours. In 17 patients, systolic BP was ≥180 mm Hg after 6.7±5.3 hours. Two patients experienced severe hypotension (systolic BP <90 mm Hg). Thus, data from a single site in Israel support the current recommendations for management of SAH in the ED.

Neutrophil to lymphocyte ratio and risk of a first episode of stroke in patients with atrial fibrillation: a cohort study

BACKGROUND

The neutrophil to lymphocyte ratio (NLR) is associated with increased risk of cardiovascular morbidity and mortality. We aimed to assess the association between NLR and first episode of stroke in patients with atrial fibrillation.

METHODS

Using the computerized database of the largest HMO in Israel, we identified a cohort of adults, aged 20 years or older, with atrial fibrillation diagnosed before 1 January 2012. Eligible subjects had no prior stroke or TIA, were not on anticoagulants at baseline, and had at least one blood cell count performed in 2011. The cohort (32,912 subjects) was followed for the first event of stroke or TIA until 31 December 2012.

RESULTS

Overall 981 subjects developed stroke during a follow-up of 30,961 person-years (stroke rate, 3.17 per 100 person-years). The incidence rate of stroke increased across NLR quartiles: 2.27, 2.72, 3.26 and 4.54 per 100 person-years, respectively. Cox proportional hazard regression analysis adjusting for the individual CHA2 DS2 -VASc score risk factors showed that, compared with the lowest NLR quartile, the HR for stroke was 1.11 (95% CI, 0.91-1.35), 1.25 (1.03-1.51) and 1.56 (1.29-1.88) for the second, third and highest quartile, respectively. On stratified analysis, NLR refined the risk of stroke across all CHA2 DS2 -VASc score strata. Adding NLR to the CHA2 DS2 -VASc score increased the AUC from 0.627 (95% CI, 0.612-0.643) to 0.635 (0.619-0.651) (P = 0.037).

CONCLUSIONS

The neutrophil to lymphocyte ratio is directly associated with the risk of stroke in patients with atrial fibrillation. Future studies are needed to replicate these findings.