Dual-energy x-ray absorptiometry scanner mismatch in follow-up bone mineral density testing

Scanner mismatch occurs frequently with follow-up dual-energy x-ray absorptiometry (DXA) scans. Nearly one-in-five follow-up DXA scans were conducted on non-cross-calibrated scanners (scanner mismatch) and more than a quarter of patients who had a follow-up DXA scan had experienced scanner mismatch.

INTRODUCTION

Detecting significant changes in bone mineral density (BMD) with dual-energy x-ray absorptiometry (DXA) scanners relies on the least significant change (LSC). Results from two different DXA scanners can only be compared, albeit with decreased sensitivity for change, if the LSC between the two scanners has been directly determined through cross-calibration. Performing follow-up DXA scans on non-cross-calibrated scanners (scanner mismatch) has safety and economic implications. This study aims to determine the proportion of scanner mismatch occurring at a population level.

METHODS

All patients who completed at least two DXA scans between 1 April 2009 and 31 December 2018 in the province of Alberta, Canada, were identified using population-based health services databases. Scanner mismatch was defined as a follow-up DXA scan completed on a DXA scanner that differed from and was not cross-calibrated to the previous DXA scanner. Multivariate logistic regression models were used to assess predictive factors that may contribute to scanner mismatch.

RESULTS

A total of 264,866 patients with 470,641 follow-up DXA scans were identified. Scanner mismatch occurred in 18.9% of follow-up DXA scans; 28.7% of patients experienced at least one scanner mismatch. Longer duration between scans (OR 1.25, 95% CI 1.24-1.26) and major osteoporotic fracture history before index scan (OR 1.06, 95% CI 1.03-1.08) increased risk of scanner mismatch. Osteoporosis medication use before index scan (OR 0.89; 95% CI 0.88-0.91), recency of follow-up scans (OR 0.98, 95% CI 0.73-0.98), female sex (OR 0.97, 95% CI 0.94-1.00), and age at last scan (OR 0.99, 95% CI 0.99-1.00) were associated with lower risk of scanner mismatch.

CONCLUSION

Scanner mismatch is a common problem, occurring in one-in-five follow-up DXA scans and affecting more than a quarter of patients. Interventions to reduce this large proportion of scanner mismatch are necessary.

Adopting a systems view of disrupting crisis-driven food insecurity

Objectives

During the COVID crisis, the incidence of food insecurity worsened around the globe. We were reminded that: food insecurity existed before COVID, worsened during this crisis, and will unfortunately be a persistent phenomenon in the post-COVID world. It is evident that to counter this public health threat, systematic changes will need to happen. In this short communication, we introduce the notion of a systems-oriented framework that can guide appropriate actions for us to disrupt future food insecurity crises.

Study design

This short communication identifies preliminary observations based on relevant past studies that documented the impact of COVID-19 on food insecurity, and the researchers’ conceptualization of a framework on how we may address future crisis-driven food insecurity challenges.

Methods

Systems-oriented framework was conceptualized based on preliminary observations in studies that investigated food insecurity during the COVID-19 pandemic.

Results

This short communication explores the notion of a systems-oriented framework as a guide to future action to prevent crisis-driven food insecurity.

Conclusions

The systems-oriented framework emphasizes the importance of action across macro, meso, and micro levels, and synchronization to maximize synergies.

Subcutaneous administration, higher age and lower renal function are associated with erythrocyte methotrexate accumulation in Crohn's disease: a cross-sectional study

Background

Methotrexate is an immunomodulatory drug for patients with Crohn’s disease. Erythrocyte MTX-polyglutamates (MTX-PG_1-5) may be used for therapeutic drug monitoring (TDM) as MTX-PG is thought to mediate MTX’s efficacy. Information on determinants of the concentration of MTX-PG in patients with Crohn’s disease is lacking. We aim to identify clinical and biochemical determinants of the erythrocyte MTX-PG_1-5 and MTX-PG_total concentration in patients with Crohn’s disease.

Methods

Adults with Crohn’s disease on methotrexate treatment who visited the outpatient clinic of Amsterdam UMC were included. Erythrocyte MTX-PGs were measured by tandem mass spectrometry.

Results

Nineteen patients were included, with a median duration of MTX use of 77 months (range 7–202). Twelve patients received MTX monotherapy, whereas 7 patients were on concomitant TNF-α inhibitors. The mean dose of MTX was 15.5 mg (SD ± 2.8) and 12 (63%) patients used subcutaneous MTX. MTX-PG_1-5 were successfully measured in 18 patients, showing substantial variability in concentrations of MTX-PG_total and individual species. The median MTX-PG_total was 117.1 nmol/L (range 46.4–258.7) with preferential accumulation of MTX-PG₃ (43.1 nmol/L, range 15.3–96.1). Patients on subcutaneous compared to oral MTX had higher median MTX-PG_(4,5) levels (55 versus 9 nmol/L, p = 0.01). Higher age (β = 0.71) and lower estimated glomerular filtration rate (β = − 0.52) were associated with a significantly higher MTX-PG_total concentration (R² = 0.60, p = 0.001).

Conclusion

MTX-PG concentrations display a considerable inter-individual variability. Higher MTX-PG accumulation is associated with subcutaneous administration, higher age, and lower renal function in Crohn’s disease patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02439-y.

POS0411 COMPARISON OF MTX-POLYGLUTAMATE ACCUMULATION PROFILES IN PERIPHERAL BLOOD MONONUCLEAR CELLS AND ERYTHROCYTES DURING 6 MONTHS MTX-THERAPY IN THE METHOTREXATE MONITORING (MeMo) TRIAL

Background

Optimal dosing of methotrexate (MTX) in rheumatoid arthritis (RA) remains challenging. To this end, monitoring of intracellular MTX polyglutamates (MTX-PGs) in red blood cells (RBCs) has been investigated as a potential marker of MTX (non-)response, with contradictory results. As enucleated, non-proliferative cells, mature RBCs lack regulated folate metabolism and are devoid of folylpolyglutamate synthetase (FPGS) activity catalyzing the conversion of MTX to MTX-PGs. Therefore, it has been argued that analysis of MTX-PG in immune-effector cells, represented by peripheral blood mononuclear cells (PBMCs), would be more relevant. However, no prospective study has been performed measuring MTX-PG levels in PBMCs nor in comparison with RBCs.

Objectives

To investigate the pharmacokinetics of MTX-PG accumulation in RBCs and PBMCs in newly diagnosed RA patients in the early phase of MTX treatment.

Methods

In a clinical prospective cohort study (Methotrexate Monitoring (NTR7149)), RA patients were administered MTX op to 25 mg/week, as described before. (1) At 1, 2, 3 and 6 months after start of therapy, blood was collected and RBCs were isolated by centrifugation and PBMCs after Ficoll density gradient centrifugation. MTX-PG1-6 concentrations in these cells were analyzed using a UPLC-MS/MS method with including custom-made stable isotopes of MTX-PG1-6 as internal standards. (2) UPLC-MS/MS measurements for MTX-PG1-6 were performed with a Waters Acquity BEH C18 column coupled to an AB Sciex 6500+ with the ESI operating on the positive mode. MTX dosing and concomitant treatments were in conformity with clinical practice. (3)

Results

46 consecutive patients were included in this study; 76% female, mean age: 57.8 years, mean baseline DAS28-ESR: 3.5, as described before. (1) Mean dosage was 10.5 mg (SD: 1.5) at baseline, 16.3 mg (2.5) at month 1, 22.7 mg (4.5) at month 2, 19.5 mg (6.3) at month 3 and 19.1 mg (6.2) at month 6.

MTX-PG accumulation in PBMCs and RBCs revealed a disparate profile in both MTX-PG distribution and absolute accumulation levels (Figure 1A/B). Remarkably, MTX-PG distribution in PBMCs was mainly composed of MTX-PG1 (58%), and to a lesser extent MTX-PG2 (27%) and MTX-PG3 (15%). Longer chain MTX-PG4-6 were also detectable in PBMCs, but at lower levels (mean: 4.0 – 6.7 fmol/10^6 cells) than MTX-PG1-3. Moreover, this MTX-PG distribution profile in PBMCs remained constant over a MTX therapy period of 6 months (Figure 1A). The RBC MTX-PG accumulation profile shows mainly MTX-PG1 and lower levels of MTX-PG2-6 at 1 month after the start of therapy. After 3 months of therapy, MTX-PG3 is the main PG-moiety with also MTX-PG4,5,6 being detected. This profile is largely similar after 6 months of therapy. With respect to total intracellular MTX-PG1-6 accumulation, PBMCs had significantly (p<0.001) 10-20-fold higher levels than RBCs at all analyzed time points (Figure 1A/B). Total MTX-PG1-6 levels in RBCs and PBMCs at all time points were weakly correlated (r=0.41, p<0.01) (Figure 1C).

Figure 1.

Individual MTX-PG concentrations in PBMCs (A) and RBCs (B) during the first 6 months of MTX administration (note the different scaling of the y-axes). At 6 months, 36 patients were still on MTX treatment. Panel (C): Spearman’s correlation plot of total MTX-PGs in RBCs versus PBMCs of all time points.

The disparate MTX-PG accumulation and distribution profiles in PBMCs versus RBCs of RA patients may be associated with the shorter life span of PBMCs and the low FPGS activity in RBCs. (4)

No significant relation between MTX-PGs and DAS28 was found (data not shown).

Conclusion

This study shows that in newly diagnosed RA patients starting MTX therapy, MTX-PG concentrations in PBMCs are significantly 10-20-fold higher than in RBCs over a period of 6 months, with a disparate MTX-PG distribution profile in PBMCs (highest: MTX-PG1) than RBCs (highest: MTX-PG3).

References

[1]RCF Hebing, Arthr Rheum (2021)

[2]E den Boer, Anal Bioanal Chem (2013)

[3]J Smolen, Ann Rheum Dis (2020)

[4]IB Muller, Ther Drug Monit (2019)

Acknowledgements

Acknowledgements: We would like to thank all participating patients and Pfizer (grant 53233663 / WI230458), AmsterdamUMC (AI&II extension grant) and NVKC (Noyons grant 2018)

Disclosure of Interests

Renske Hebing Grant/research support from: Pfizer (grant 53233663 / WI230458), NVKC (Netherlands Society for Clinical Chemistry, Noyons grant 2018) and AmsterdamUMC (extension grant), Marry Lin: None declared, Eduard Struys: None declared, Sohaila Mahmoud: None declared, Ittai Muller: None declared, Sandra Heil: None declared, Pieter Griffioen: None declared, WIllem Lems: None declared, Bart van den Bemt Speakers bureau: Pfizer, UCB, Sanofi-Aventis, Galapagos, Amgen and Eli Lilly, Michael Nurmohamed Grant/research support from: Pfizer grant 53233663 / WI230458, Gerrit Jansen: None declared, Robert De Jonge Grant/research support from: NVKC (Netherlands Society for Clinical Chemistry, Noyons grant)

AB0061 PHARMACOKINETICS OF METHOTREXATE POLYGLUTAMATES IN PERIPHERAL BLOOD MONONUCLEAR CELLS OF RA PATIENTS IS SIMILAR AFTER SUBCUTANEOUS OR ORAL ADMINISTRATION IN THE METHOTREXATE MONITORING (MeMo) TRIAL

Background

Pharmacokinetics of methotrexate (MTX) after oral and subcutaneous administration to RA patients differs: MTX levels in plasma and MTX-polyglutamate (MTX-PG) accumulation in erythrocytes are higher during equidosed subcutaneous compared to oral MTX treatment. (1,2) No data are available whether administration route of MTX differentially impacts the intracellular concentrations of MTX-PGs in peripheral blood mononuclear cells (PBMCs) during MTX therapy.

Objectives

To investigate the pharmacokinetics of MTX-PGs in PBMCs of newly diagnosed RA patients receiving oral or subcutaneous MTX in the early phase (1, 2, 3 and 6 months) of MTX treatment.

Methods

In a clinical prospective cohort study (MeMo study (NTR7149)), RA patients were

administered oral (n=24) or subcutaneous (n=22) MTX up to 25 mg MTX/week, as described before. (1) At 1, 2, 3 and 6 months after the start of therapy, PBMCs were isolated via Ficoll density gradient centrifugation. Individual MTX-PG forms (MTX-PG1-6) in PBMCs were analyzed by a UPLC-MS/MS method including custom-made stable isotopes of MTX-PG1-6 as internal standards (3). UPLC-MS/MS measurements of the PBMCs were performed with a Waters Acquity BEH C18 column coupled to an AB Sciex 6500+ with the ESI operating on the positive mode. Dosing, concomitant treatments and DAS28-ESR assessments were in conformity with clinical practice. (4)

Results

46 consecutive patients were included in this study; 76% female, mean age: 57.8 years, BMI: 25.8, smokers: 20%, mean baseline DAS28-ESR: 3.5, as described before. (1) MTX dose at baseline was 10.5 mg (SD: 1.5) for both groups, 15.4 mg (4.4) and 16.8 mg (1.8) at 1 month, 22.8 mg (3.9) and 22.4 mg (5.2) at 2 months, 20.1 mg (6.3) and 20.8 mg (5.6) at 3 months, and 19.7 mg (6.1) and 18.5 mg (6.7) at 6 months for oral and subcutaneous use, respectively. MTX-PG analyses in PBMCs for individual and total MTX-PGs revealed no significant differences between oral and subcutaneous administration groups at 1, 2, 3, and 6 months (Figure 1). Linear regression of LN transformed MTX-PG levels in PBMCs and administration route, corrected for age, baseline DAS28, smoking, BMI, eGFR and MTX dose, showed a trend towards higher MTX-PG levels in PBMCs after subcutaneous MTX administration compared to oral administration (data not shown). MTX-PG distribution in PBMCs was mainly composed of MTX-PG1 (58%), and to a lesser extent MTX-PG2 (27%) and MTX-PG3 (15%). Longer chain MTX-PGs beyond MTX-PG4 were detectable in PBMCs, but at levels lower than MTX-PG1-3 (mean: 4.0 – 6.7 fmol/106 cells). Total MTX-PG accumulation in PBMCs was approximately 10-20 fold higher than in erythrocytes. PBMC accumulation was rather stable, whereas RBC MTX-PG accumulation increased between 1 to 3 months to reach a plateau (Figure 1).

Figure 1.

Loess regression of MTX-PG concentrations in PBMCs (MTX-PG1-3) and RBCs (MTX-PG1-6) of RA patients during the first 6 months of oral or subcutaneous MTX administration. At 6 months, 18 patients using oral and 18 patients using subcutaneous MTX were still continuing MTX treatment. Means (lines) and SE (grey areas) are depicted.

Conclusion

This study demonstrated that MTX-PG accumulation in PBMCs early on in the MTX treatment of RA patients was not significantly different between oral or subcutaneous MTX administration routes.

References

[1]RCF Hebing et al, Arthritis Rheum (2021); 60:339-348

[2]M Hoekstra et al, J Rheumatol (2004); 31:645-8

[3]E Den Boer et al, Anal Bioanal Chem (2013); 405: 1673-1681

[4]J Smolen et al, Ann Rheum Dis (2020); 79:685-699

Acknowledgements

We would like to thank all participating patients and Pfizer (grant 53233663 / WI230458), NVKC (Noyons grant) and AmsterdamUMC (AI&II extension grant).

Disclosure of Interests

Renske Hebing Grant/research support from: Pfizer, grant number 53233663 / WI230458, Amsterdam UMC (AI&II extension grant), NVKC (Netherlands Society for Clinical Chemistry, Noyons grant), Marry Lin: None declared, Eduard Struys: None declared, Sohaila Mahmoud: None declared, Ittai Muller: None declared, WIllem Lems: None declared, Bart van den Bemt Speakers bureau: Pfizer, UCB, Sanofi-Aventis, Galapagos, Amgen and Eli Lilly, Gerrit Jansen: None declared, Robert De Jonge Grant/research support from: NVKC (Netherlands Society for Clinical Chemistry, Noyons grant), Michael Nurmohamed Grant/research support from: Pfizer grant

Correlation of KMT2 family mutations with molecular characteristics and prognosis in colorectal cancer

BACKGROUND

Lysine methyltransferase 2 (KMT2) family proteins methylate lysine 4 on histone H3 (H3K4) to promote genome accessibility and transcription. Dysregulation or mutation of KMT2 family have been observed frequently in various types of human cancers. Colorectal cancer is the third most common cancer worldwide. However, few studies have evaluated the role of KMT2 family mutations in colorectal cancer. The present study aimed to explore the impact of KMT2 family mutations on clinicopathological, molecular characteristics and prognosis in colorectal cancer.

METHODS

A total of 316 colorectal cancer patients were enrolled; tumor tissue and matched peripheral blood samples were collected and subjected to targeted sequencing with a panel of 1021 cancer-related genes. The association of clinical pathological features and molecular characteristics in patients were then analyzed. The cBioPortal dataset was used for investigating the KMT2 family mutations data and their correlation with clinical outcomes.

RESULTS

The overall mutation frequencies of KMT2A-D were 9.5%, 0.5%, 13%, and 13%, respectively, which were more often present at right-sided primary and earlier stage tumors. KMT2A-D mutations are associated with enhanced genomic instability, including a higher level of microsatellite instability (MSI-H) and tumor mutational burden (TMB-H). In addition, our results highlight the co-occurring gene mutations within the Wnt signaling, ERBB2/4, TGF-β superfamily pathway, and PI-3-kinase pathway in KMT2-mutant colorectal cancer. KMT2 family mutations were predictive biomarker for better overall survival in metastatic colorectal cancer.

CONCLUSIONS

Collectively, we identified that KMT2 family mutations were correlated with higher-TMB and higher-MSI, thus resulting in a better outcome for colorectal cancer patients.

Efficacy and safety of combination therapy with vildagliptin and metformin vs. metformin monotherapy for Type 2 Diabetes Mellitus therapy: a meta-analysis

OBJECTIVE

The aim is to assess the comparative efficacy and safety of combination therapy with vildagliptin and metformin vs. metformin monotherapy in the treatment of type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

We searched on PubMed, Cochrane Library, Web of Science, and Embase databases for randomized controlled trials (RCTs) of combination therapy with vildagliptin and metformin vs. metformin monotherapy in patients with T2DM published up to 30 February 2021. The Cochrane tool and Revman 5.3 software was used to assess the risk of bias and conducted the meta-analysis in the included RCTs. Evidence level was assessed by the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach.

RESULTS

A total of 11 RCTs and 8533 patients were included. For the efficacy, we found that combination therapy with vildagliptin and metformin (dose of metformin ≥1500mg/d) had a significantly higher reduction in hemoglobin A1c (HbA1c) [mean differences (MD)= -0.59, 95% CI (-0.28, -0.16), p<0.00001] and fasting plasma glucose (FPG) level [MD= -0.82, 95% CI (-1.09, -0.56), p<0.00001] than combination therapy with vildagliptin and metformin (dose of metformin <1500 mg/d). Vildagliptin plus metformin as combination therapy reduced body weight loss ratio [MD=0.22, 95% CI (0.17, 0.27), p<0.00001] when compared with metformin monotherapy. In terms of safety, the vildagliptin plus metformin as combination therapy did not increase risk of total adverse events (AEs) [RR=0.98, 95% CI (0.94,1.02), p=0.29], however there were significant statistical difference and did not increase the risk of diarrhea [RR=0.55, 95% CI (0.40, 0.76), p=0.0003] and Gastrointestinal (GI) disorders [RR=0.72, 95% CI (0.58, 0.91), p=0.006], but significantly increased risk of dizziness [RR=1.41, 95% CI (1.06, 1.88), p=0.02] when compared with metformin monotherapy.

CONCLUSIONS

Compared with metformin, vildagliptin combined with metformin could significantly reduce FPG, HbA1c and body weight. When the dose of metformin in the combination group of vildagliptin and metformin is ≥1500mg/d, the results showed significant reduction in HbA1c and FPG. In addition, it had no risk of increase in total AEs, diarrhea, and GI disorders, but had significant risk of increase in dizziness. GRADE showed that the quality of evidence had high certainty in FPG and moderate certainty in HbA1c, body weight and all AEs.

Use of real-time artificial intelligence in detection of abnormal image patterns in standard sonographic reference planes in screening for fetal intracranial malformations

OBJECTIVES

To develop and validate an artificial intelligence system, the Prenatal ultrasound diagnosis Artificial Intelligence Conduct System (PAICS), to detect different patterns of fetal intracranial abnormality in standard sonographic reference planes for screening for congenital central nervous system (CNS) malformations.

METHODS

Neurosonographic images from normal fetuses and fetuses with CNS malformations at 18-40 gestational weeks were retrieved from the databases of two tertiary hospitals in China and assigned randomly (ratio, 8:1:1) to training, fine-tuning and internal validation datasets to develop and evaluate the PAICS. The system was built based on a real-time convolutional neural network (CNN) algorithm, You Only Look Once, version 3 (YOLOv3). An image dataset from a third tertiary hospital was used to further validate, externally, the performance of the PAICS and to compare its performance with that of sonologists with different levels of expertise. Furthermore, a prospective video dataset was employed to evaluate the performance of the PAICS in a real-time scan scenario. The diagnostic accuracy, sensitivity, specificity and area under the receiver-operating-characteristics curve (AUC) were calculated to assess the performance of the PAICS and to compare this with the performance of sonologists with different levels of experience.

RESULTS

In total, 43 890 images from 16 297 pregnancies and 169 videos from 166 pregnancies were used to develop and validate the PAICS. The system achieved excellent performance in identifying 10 types of intracranial image pattern, with macro- and microaverage AUCs, respectively, of 0.933 (95% CI, 0.798-1.000) and 0.977 (95% CI, 0.970-0.985) for the internal validation image dataset, 0.902 (95% CI, 0.816-0.989) and 0.898 (95% CI, 0.885-0.911) for the external validation image dataset and 0.969 (95% CI, 0.886-1.000) and 0.981 (95% CI, 0.974-0.988) in the real-time scan setting. The performance of the PAICS was comparable to that of expert sonologists in terms of macro- and microaverage accuracy (P = 0.863 and P = 0.775, respectively), sensitivity (P = 0.883, P = 0.846) and AUC (P = 0.891, P = 0.788), but required significantly less time (0.025 s per image for PAICS vs 4.4 s for experts, P < 0.001).

CONCLUSIONS

Both in the image dataset and in the real-time scan setting, the PAICS achieved excellent diagnostic performance for various fetal CNS abnormalities. Its performance was comparable to that of experts, but it required less time. A CNN algorithm can be trained to detect fetal CNS abnormalities. The PAICS has the potential to be an effective and efficient tool in screening for fetal CNS malformations in clinical practice. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Thyrotoxic periodic paralysis associated with Graves’ disease: a case series

Summary

Thyrotoxic periodic paralysis (TPP) is a rare condition characterised by acute onset hypokalaemia and paralysis which most commonly affects men of Asian descent between the ages of 20 and 40 years (1, 2). It has been reported in approximately 2% of patients with thyrotoxicosis in China and Japan (1, 2, 3). Hypokalaemia in TPP results from a massive intracellular shift of potassium induced by the thyroid hormone sensitisation of Na⁺/K⁺-ATPase (4). Treatment of TPP includes prevention of this shift by using beta-blockade, rapid potassium replacement and treatment of the underlying hyperthyroidism. We present two cases of TPP with differing outcomes. In the first case, a 33-year-old Filipino gentleman presented to our emergency department (ED) with a 3-month history of recurrent proximal lower limb weakness. Serum potassium was 2.2 mmol/L (3.3–5.1) and he was given i.v. potassium replacement. Thyroid function tests (TFTs) and thyroid antibodies were consistent with Graves thyrotoxicosis. He was discharged home on carbimazole and remains well controlled on long-term medical therapy. In the second case, a 22-year-old Malaysian gentleman presented to our ED with new-onset bilateral lower limb painless paralysis. Serum potassium was 1.9 mmol/L with TFTs demonstrating Graves thyrotoxicosis. He was treated with i.v. potassium replacement and discharged home on carbimazole and propranolol. He represented to the hospital on two further occasions with TPP and was advised to consider total thyroidectomy given his refractory Graves’ disease. These cases highlight the importance of prompt recognition of this rare life-threatening complication of Graves’ disease, especially in patients of Asian descent.

Learning points

Evaluation of different late left ventricular remodeling definitions for predicting long-term outcomes in acute myocardial infarction patients undergoing percutaneous coronary intervention

Background

Late left ventricular remodeling (LLVR) after the index acute myocardial infarction (AMI) is a common complication, and is associated with poor outcome. However, the optimal definition of LLVR has been debated because of its different incidence and influence on prognosis. At present, there are limited data regarding the influence of different LLVR definitions on long-term outcomes in AMI patients undergoing percutaneous coronary intervention (PCI).

Purpose

To explore the impact of different definitions of LLVR on long-term mortality, re-hospitalization or an urgent visit for heart failure, and identify which definition was more suitable for predicting long-term outcomes in AMI patients undergoing PCI.

Methods

We prospectively observed 460 consenting first-time AMI patients undergoing PCI from January 2012 to December 2018. LLVR was defined as a ≥20% increase in left ventricular end-diastolic volume (LVEDV), or a &gt;15% increase in left ventricular end-systolic volume (LVESV) from the initial presentation to the 3–12 months follow-up, or left ventricular ejection fraction (LVEF) &lt;50% at follow up. These parameters of the cardiac structure and function were measuring through the thoracic echocardiography. The association of LLVR with long-term prognosis was investigated by Cox regression analysis.

Results

The incidence rate of LLVR was 38.1% (n=171). The occurrence of LLVR according to LVESV, LVEDV and LVEF definition were 26.6% (n=117), 31.9% (n=142) and 11.5% (n=51), respectively. During a median follow-up of 2 years, after adjusting other potential risk factors, multivariable Cox regression analysis revealed LLVR of LVESV definition [hazard ratio (HR): 2.50, 95% confidence interval (CI): 1.19–5.22, P=0.015], LLVR of LVEF definition (HR: 16.46, 95% CI: 6.96–38.92, P&lt;0.001) and LLVR of Mix definition (HR: 5.86, 95% CI: 2.45–14.04, P&lt;0.001) were risk factors for long-term mortality, re-hospitalization or an urgent visit for heart failure. But only LLVR of LVEF definition was a risk predictor for long-term mortality (HR: 6.84, 95% CI: 1.98–23.65, P=0.002).

Conclusions

LLVR defined by LVESV or LVEF may be more suitable for predicting long-term mortality, re-hospitalization or an urgent visit for heart failure in AMI patients undergoing PCI. However, only LLVR defined by LVEF could be used for predicting long-term mortality.

Funding Acknowledgement

Type of funding sources: None. Association Between LLVR and outcomesKaplan-Meier Estimates of the Mortality

Predictive value of neutrophil percentage-to-albumin ratio for contrast-associated acute kidney injury in patients without chronic kidney disease undergoing elective percutaneous coronary intervention

Background

Although previous studies have demonstrated that neutrophil and albumin are biomarkers of inflammation and malnutrition, which are highly related with contrast-associated acute kidney injury (CA-AKI). However, there has been no study investigated the combined evaluation of neutrophil and albumin in predicting CA-AKI.

Purpose

To explore the predictive value of neutrophil percentage-to-albumin ratio (NPAR) for CA-AKI in patients undergoing elective percutaneous coronary intervention (PCI).

Methods

We prospectively observed 5083 consenting patients without chronic kidney disease (CKD) undergoing elective PCI from January 2012 to December 2018. NPAR was calculated as neutrophil percentage numerator divided by serum albumin concentration. CA-AKI was defined as an increase in serum creatinine (SCr) ≥50% or 0.3 mg/dL within 48 hours after contrast medium exposure. The association between NPAR and CA-AKI was investigated by logistic regression analysis. The area under the receiver-operating characteristic curve (AUC), continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were calculated to make comparison for CA-AKI prediction.

Result

The incidence of CA-AKI was 5.6% (n=286). The median NPAR was 14.9 (13.0–17.1). According to the receiver operating characteristic curves (ROC), the best cut-off value of NPAR for predicting CA-AKI was 15.7 with 66.8% sensitivity and 61.9% specificity (C statistic=0.679; 95% CI, 0.666–0.691). NPAR displayed higher AUC value in comparison to neutrophil percentage (p&lt;0.001), but not albumin (P=0.063), as a predictor of CA-AKI. However, NPAR significantly improved the prediction of CA-AKI in the continuous NRI and IDI over neutrophil percentage (NRI: 0.353, 95% CI: 0.234–0.472, P&lt;0.001; IDI: 0.017, 95% CI: 0.010–0.024, p&lt;0.001) and albumin (NRI: 0.141, 95% CI: 0.022–0.260, P=0.020; IDI: 0.009, 95% CI: 0.003–0.015, p=0.003) alone. After adjusting for potential confounding risk factors of CA-AKI, multivariable logistic analysis showed that NPAR &gt;15.7 was a strong independent predictor of CA-AKI (OR=1.998, 95% CI, 1.511–2.643, p&lt;0.001).

Conclusion

NPAR is an independent predictor of CA-AKI, which significantly improved the prediction of CA-AKI over neutrophil and albumin alone in patients without CKD undergoing elective PCI.

Funding Acknowledgement

Type of funding sources: None. ROC for NPAR to predict CA-AKIPredictors of CA-AKI

The De-Ritis ratio is associated with contrast-associated acute kidney injury in patients undergoing elective percutaneous coronary intervention

Background

Preoperative liver dysfunction has been demonstrated as a poor prognostic factor after major surgery. Recent researches discovered that an increased De-Ritis ratio (aspartate aminotransferase-to-alanine aminotransferase ratio) reflects the liver dysfunction and was associated with adverse cardiovascular and renal outcomes. However, there is a lack of data exploring the predictive value of the De-Ritis ratio on contrast-associated acute kidney injury (CA-AKI) in patients undergoing elective percutaneous coronary intervention (PCI).

Purpose

To evaluate the predictive value of the De-Ritis ratio for CA-AKI in patients undergoing elective PCI.

Methods

We conducted a prospective, observational study with 5780 consenting patients undergoing elective PCI from January 2012 to December 2018. CA-AKI was defined as an increase in serum creatinine (SCr) ≥50% or 0.3 mg/dL within 48 hours after contrast medium exposure. The relationship between the De-Ritis ratio and CA-AKI was investigated by logistic regression analysis. The predictive utility of the De-Ritis ratio was determined and compared using the area under the receiver-operating characteristic curve (AUC).

Result

CA-AKI developed in 363 (6.3%) patients. The median De-Ritis ratio was 1.00 (0.77–1.33). The De-Ritis ratio showed an AUC of 0.636 (95% confidence interval (CI): 0.624–0.649; P&lt;0.001) in predicting CA-AKI, which was significantly greater than aspartate aminotransferase (AST) (AUC: 0.636 vs 0.589, p=0.015) and alanine aminotransferase (ALT) (AUC: 0.636 vs 0.506, p&lt;0.001). The best cut-off value of the De-Ritis ratio for predicting CA-AKI was 1.30 with 47.1% sensitivity and 74.7% specificity. Multivariable logistic analysis showed that the De-Ritis ratio &gt;1.30 was a remarkable independent predictor of CA-AKI (OR=1.757, 95% CI, 1.385–2.229, p&lt;0.001) even after adjusting for other CA-AKI risk factors.

Conclusion

The De-Ritis ratio is an independent risk factor for predicting CA-AKI in patients undergoing elective PCI.

Funding Acknowledgement

Type of funding sources: None. ROC for De-Ritis ratio to predict CA-AKIPredictors of CA-AKI

[Drug-resistant gene polymorphisms in Plasmodium falciparum isolated from Bioko Island, Equatorial Guinea in 2018 and 2019]

OBJECTIVE

To investigate the genetic polymorphisms of Plasmodium falciparum multidrug resistance protein 1 (PfMDR1), chloroquine resistance transporter (PfCRT) and Kelch 13 (PfK13) genes in Bioko Island, Equatorial Guinea, so as to provide insights into the development of the malaria control strategy in local areas.

METHODS

A total of 85 peripheral blood samples were collected from patients with Plasmodium falciparum infections in Bioko Island, Equatorial Guinea in 2018 and 2019, and genomic DNA was extracted. The PfMDR1, PfCRT and PfK13 genes were amplified using a nested PCR assay. The amplification products were sequenced, and the gene sequences were aligned.

RESULTS

There were no mutations associated with artemisinin resistance in PfK13 gene in Bioko Island, Equatorial Guinea, while drug-resistant mutations were detected in PfMDR1 and PfCRT genes, and the proportions of PfMDR1_N86Y, PfMDR1_Y184F and PfCRT_K76T mutations were 35.29% (30/85), 72.94% (62/85) and 24.71% (21/85), respectively.

CONCLUSIONS

There are mutations in PfMDR1, PfCRT and PfK13 genes in P. falciparum isolates from Bioko Island, Equatorial Guinea.

P–412 Low serum hCG levels adjusted for the hCG trigger dose in fresh cycles may be associated with a poor clinical pregnancy rate of FET cycles

Study question

Is there any association between serum human chorionic gonadotropin (hCG) levels after trigger at previous fresh cycles and pregnancy outcomes of frozen-thawed embryo transfer (FET) cycles?

Summary answer

Low adjusted serum hCG level after hCG trigger at fresh cycles is negatively associated with clinical pregnancy rates (CPR) of hormone replacement treatment-FET (HRT-FET). What is known already: Literature showed that low serum hCG levels after the same dose of hCG trigger was associated with reduced pregnancy outcomes of the fresh cycles. However, the relationship between hCG levels after trigger at fresh cycles and pregnancy outcomes of FET cycles remains unknown.

Study design, size, duration

This matched retrospective study was conducted at a Reproductive Medicine Center between 2016 and 2018. Subjects performing HRT-FET cycles, whose previous fresh cycles used a bolus of hCG alone or a bolus of GnRHa combined with hCG for trigger were included. A total of 186 HRT-FET cycles with complete data was included for the final analysis.

Participants/materials, setting, methods

The study population was grouped into women with intramuscular injection of hCG prior to secretory transformation (hCG group, n = 93) and a comparison group (control group, n = 93) of women without hCG addition matched for patients’ age and duration of infertility. At the previous fresh cycles, serum hCG levels were measured 12 hours later after hCG trigger (defined as the “hCG+12 h” timepoint), and were adjusted for doses (defined as adjusted hCG levels). Main results and the role of chance: For patients achieving clinical pregnancy, the adjusted hCG level significantly increased (P &lt; 0.05). Meanwhile, the ROC curve also showed a significantly predictive value of adjusted serum hCG levels at the “hCG+12 h” timepoint for CPR in HRT- FET cycles (AUC=0.626, 95%CI: 0.512–0.740) and the optimal hCG threshold proposed by ROC for CPR was 46.31 mIU/mL with sensitivity of 71.4% and specificity of 56.9%. For all patients, the CPR in hCG group was significantly higher than that in control group (61.3% vs. 44.1%). Furthermore, all cycles were then divided into four groups based on the injection of hCG prior to secretory transformation in HRT-FET cycles and this cut-off value of hCG levels at the “hCG+12 h” timepoint. For patients with adjusted hCG levels ≤46.31 mIU/mL, the CPR was significantly improved in hCG group compared with control group (61.1% vs. 29.3%). But for patients with adjusted hCG levels &gt;46.31 mIU/mL, no statistically significant difference was observed between the hCG and control group (61.4% vs. 55.8%).

Limitations, reasons for caution

Although the results achieved statistically significant, the sample size was relatively small, which limits our ability to draw a definitive conclusion. The reason of the small sample size may be that to reduce the risk of OHSS, doctors would give preference to trigger with GnRH agonist in our center.

Wider implications of the findings: Adjusted serum hCG levels might represent a potential factor to guide adequate support in the subsequent HRT-FET cycles. Meanwhile, for patients with low adjusted serum hCG levels, intramuscular hCG injection prior to secretory transformation may be a good compensation way to rescue pregnancy impair in the subsequent HRT-FET cycles.

Trial registration number

N/A.

[Study of B10 cells in the pathogenesis of the interaction between chronic obstructive pulmonary disease and periodontal disease]

Objective: To determine the ratio of ingerleukin(IL)-10 secreting regulatory B cells (B10 cells) and the levels of IL-10 in peripheral blood of periodontitis patients with or without chronic obstructive pulmonary disease (COPD), and to explore the function of B10 cells in the pathogenesis of the interaction between COPD and periodontitis. Methods: Forty-five periodontitis patients and healthy people were recruited and divided into three groups: COPD group, COPD+periodontitis group and health controls with 15 people in each group. Peripheral blood samples were collected to determine the B10 population. Another group of 93 periodontitis patients and healthy people were also collected and divided into the same 3 groups with 31 people in each group. Peripheral blood samples were collected to determine the cytokine IL-10. Results: After stimulation with lipopolysaccharide (LPS)+phorbol-12-myristate13-acetate+ionomycin+brefeldin A (PIB) for 5 h, the ratio of B10 in COPD+periodontitis group [(0.44±0.11)%] was significantly lower than that in the control group [(0.63±0.14)%] and periodontitis group [(0.62±0.13)%] (P<0.01), respectively. The ratio of B10 cells showed no significant difference between periodontitis group and healthy control group (P>0.05). After stimulation with LPS+PIB for 48 h, the ratio of B10 cells in COPD+periodontitis group [(7.59±1.33)%] was significantly lower than that in the periodontitis group [(10.14±2.02)%] and the healthy controls [(11.80±1.71)%] (P<0.01), respectively. The ratio of B10 cells in periodontitis group was significantly lower than that in the healthy controls (P<0.05). The levels of IL-10 in periodontitis group [(2.55±0.61) ng/L] and COPD+periodontitis group [(1.95±0.45) ng/L] were significantly lower than that in the control group [(3.96±1.15) ng/L] (P<0.01) respectively. Moreover, the level of IL-10 in COPD+periodontitis group was significantly lower than that in the periodontitis group (P<0.01). Conclusions: The dysfunction of immune system caused by the decreased proportion of B10 cells might be involved in the pathological process of COPD promoted by periodontitis.

[Protein Disulfide Bonds Detected by Tagging with High Molecular Weight Maleimide Derivative]

Disulfide bridges are essential for maintaining the structure and function of proteins. Traditionally, studies of the disulfide bonds require expensive equipment and high purity of the protein sample, therefore, the development of simpler techniques is warranted. Here, were present a novel protocol for the detection of disulfide bonds in proteins, which is based on the labeling reduced disulfide bridges with a high molecular weight (HMW) maleimide derivative. After irreversible blocking of free thiol groups of proteins, the labeling of new thiols released from disulfide bridges with a high-molecular-weight (HMW) maleimide derivative is performed. To confirm localization of cysteines involved in the formation of disulfide bonds, cysteine mutagenesis was conducted. For validation, aquaporin 5 (AQP5) and transient receptor potential cation channel subfamily V member 4 (TRPV4) proteins were tagged with FLAG (DYKDDDDK) on N-termini. Increase in MW of the target proteins from immunoblot indicated the presence of disulfide bonds. No bands with increased MW were detected in AQP5, while TPRV4 cysteines at disulfide bridges-constituting positions 639, 645, 652, 660, 770 were detected and confirmed by cysteine mutagenesis. These data indicate that the proposed technique is feasible and effective for the detection of protein disulfide bonds.

AB0251 INCREASED ACCUMULATION OF ERYTHROCYTE METHOTREXATE POLYGLUTAMATES DURING EARLY PHASE SUBCUTANEOUS VERSUS ORAL METHOTREXATE TREATMENT OF RHEUMATOID ARTHRITIS PATIENTS

Background:

Optimal dosing of methotrexate (MTX) for individual rheumatoid arthritis (RA) patients to achieve adequate disease control is an ongoing challenge. Assessment of erythrocyte MTX-polyglutamates (PGs) levels has been employed as a tool to monitor clinical response of RA patients in the first 3-12 months of treatment and MTX-PG2-4 and total MTX-PGs were associated with a lower DAS28 over 9 months.1 However, data from earlier time points, MTX-PG6 and per route of administration are unavailable.

Objectives:

To investigate the pharmacokinetics and -dynamics of erythrocyte MTX-PG accumulation in RA patients receiving oral or subcutaneous MTX in the early phase (1, 2, and 3 months) of MTX treatment initiation.

Methods:

In a clinical prospective cohort study (MeMo study (NTR7149)), newly diagnosed RA patients were administered oral (n=24) or subcutaneous (n=22) MTX, mostly according to the COBRA-light schedule (start 10 mg MTX, increased to 25 mg MTX in 8 weeks). At 1, 2, and 3 months after start of therapy, blood was collected and individual MTX-PGs (MTX-PG1 – MTX-PG6) were analyzed in erythrocytes at a minimal detection limit of 1 nmol/L, using a validated UHPLC-MS/MS method with labeled internal standards.1 Dosing, concomitant treatments and DAS28-ESR assessments were in conformity with clinical practice. Adverse events were recorded.

Results:

46 consecutive patients were included in this study; 76% female, mean age: 57.8 years, BMI: 25.8, 20% smokers, mean baseline DAS28-ESR: 3.5. Notwithstanding marked interpatient variability, patients starting subcutaneous MTX had accumulated significantly higher (approximately 2-fold) long chain MTX-PGs (MTX-PG4-6) when compared to patients in the oral MTX group at 1 and 2 months (Figure 1A, Table 1). Similarly, MTX-PG1-6 and MTX-PG3 accumulation were higher in subcutaneous MTX-users at month 1 (p=0.022 and p=0.011) compared to the oral group (median 68.6 nmol/L (IQR:40.5) vs 51.9 (55.6) and 17.4 (11.1) vs 11.2 (15.6), respectively (Figure 1B, Table 1).

Table 1.

Linear regression of MTX-PG levels and administration route, corrected for age, baseline DAS28, smoking, BMI, eGFR and MTX dose.

monthß (P-value)1ß (P-value)2ß (P-value)3MTX-PG1-61.65 (0.022)1.51 (0.073)1.30 (0.233)MTX-PG1,21.13 (0.599)1.19 (0.470)1.12 (0.623)MTX-PG31.75 (0.011)1.51 (0.071)1.19 (0.439)MTX-PG4-61.97 (0.036)2.04 (0.033)1.55 (0.136)

Mean MTX dose at baseline was 10.5mg (SD 1.5) for both groups, 15.4 (4.4) and 16.8 (1.8) at 1 month and 22.8 (3.9) and 22.4 (5.2) at 2 months for oral and subcutaneous use respectively.

DAS28 decreased with 1.6 in the oral group and 1.1 in the subcutaneous group (p=0.382). With and without corrections for age, baseline DAS28, eGFR, MTX dose (1 month before sampling), smoking and BMI, no significant relation between MTX-PG concentrations and DAS28 was observed during the first 3 months of treatment.

43 patients reported any side effect, mostly headache and dizziness, which was similar in both groups and uncorrelated with MTX-PG levels.

No association was found between MTX-PG1 levels and number of days between timing of blood withdrawal and last administration.

Figure 1.

Erythrocyte long chain MTX-PG(A) and total MTX-PG(B) accumulation in RA patients of the first 3 months of oral(C) or subcutaneous(D) MTX administration. At 3 months, 18 patients using oral and 18 patients using subcutaneous MTX were still continuing MTX treatment. Medians and IQR are depicted.

Conclusion:

This study shows the feasibility of measuring erythrocyte MTX-PGs early on in the treatment of RA patients with MTX and demonstrated significantly higher accumulation of MTX-PGs following subcutaneous versus oral MTX administration. Early phase erythrocyte MTX-PG analyses may hold potential for positioning in optimizing individual patient MTX dose scheduling.

References:

[1]de Rotte MC, et al. Methotrexate polyglutamates in erythrocytes are associated with lower disease activity in patients with rheumatoid arthritis. Ann Rheum Dis 2015(74):408-14.

Acknowledgements:

We would like to thank all participating patients and Pfizer (grant 53233663 / WI230458).

Disclosure of Interests:

Renske Hebing Grant/research support from: Pfizer, Ittai Muller: None declared, Marry Lin: None declared, Sohaila Mahmoud: None declared, Sandra Heil: None declared, WIllem Lems: None declared, Michael Nurmohamed: None declared, Robert De Jonge: None declared, Gerrit Jansen: None declared