Effect of proteinuria at relapse on shear wave velocity assessed using ultrasound elastography in children with idiopathic nephrotic syndrome

PURPOSE

Shear wave velocity (SWV) is an ultrasound elastography technique that provides much information for kidney disease assessment. However, the factors that alter SWV are not fully understood; it is unclear whether the variation in SWV seen in proteinuria associated with disease progression is due to tissue or proteinuria. This study investigated the effect of proteinuria on SWV.

METHODS

This prospective observational study compared SWV at remission with SWV at relapse in children treated for idiopathic nephrotic syndrome (INS) between April 2020 and December 2023. All relapses without oral steroids during the observation period were measured. SWV at remission was defined as the date closest to relapse during which repeated measurements were taken approximately every 3 months after steroid discontinuation.

RESULTS

Eight patients were treated for INS with a median observation period of 21.9 months (11.8-27.1). Of the 15 relapses, five that met the definition were considered for the study. The median interval between the measurement at relapse and remission was 40 days (11-55). SWV was significantly lower at relapse than remission (2.40 ± 0.20 m/s vs. 2.14 ± 0.15 m/s, P < 0.01).

CONCLUSIONS

SWV decreased in the presence of severe proteinuria at relapse compared to the remission measurements. Although more cases need to be studied, the decrease in SWV may reflect the mechanism by which protein leaks into the urine, not just a direct change caused by the presence of proteinuria.

Pathological Factors Affecting the R2* Values of the Kidney in Blood Oxygenation Level-dependent MR Imaging: A Retrospective Study

PURPOSE

Despite the usefulness of blood oxygenation level-dependent (BOLD) MRI in assessing glomerulonephritis activity, its relationship with histological findings remains unclear. Because glomerulonephritis presents multiple complex injury patterns, analysis of each pattern is essential. We aimed to elucidate the relationship between the histological findings of the kidney and BOLD MRI findings in mesangial proliferative glomerulonephritis.

METHODS

Children under 16 years of age diagnosed with mesangial proliferative glomerulonephritis by kidney biopsy at our university hospital between January 2013 and September 2022 were included in this study. Cortical and medullary spin relaxation rate (R2*) values were measured using BOLD MRI at 3T within two weeks before and after the kidney biopsy. The R2* values, including the fluctuations with low-dose oxygen administration, were retrospectively examined in relation to the cortical (mesangial proliferation, endothelial cell proliferation, crescent, sclerosis, and fibrosis) and medullary findings (fibrosis).

RESULTS

Sixteen times kidney biopsies were performed for glomerulonephritis during the study period, and one patient was excluded because of comorbidities; the remaining 14 patients included six boys with a mean age of 11.9 ± 3.5 years at the BOLD examination. None of the patients had medullary fibrosis. Among the kidney tissue parameters, only sclerosis showed a significant correlation with R2* values: medulla with R2* values under atmospheric pressure (r = 0.53, P < 0.05) and cortex with the rate of change in R2* values with low-dose oxygen administration (r = -0.57, P < 0.03). In the multiple regression analysis, only sclerosis was an independent contributor to the change in R2* values with oxygen administration in the cortex (regression coefficient -0.109, P < 0.05).

CONCLUSION

Since the R2* values reflect histological changes in the kidney, BOLD MRI may facilitate the evaluation of mesangial proliferative glomerulonephritis, potentially reducing the patient burden.

USP8 prevents aberrant NF-κB and Nrf2 activation by counteracting ubiquitin signals from endosomes

K63-linked ubiquitin chains attached to plasma membrane proteins serve as tags for endocytosis and endosome-to-lysosome sorting. USP8 is an essential deubiquitinase for the maintenance of endosomal functions. Prolonged depletion of USP8 leads to cell death, but the major effects on cellular signaling pathways are poorly understood. Here, we show that USP8 depletion causes aberrant accumulation of K63-linked ubiquitin chains on endosomes and induces immune and stress responses. Upon USP8 depletion, two different decoders for K63-linked ubiquitin chains, TAB2/3 and p62, were recruited to endosomes and activated the TAK1-NF-κB and Keap1-Nrf2 pathways, respectively. Oxidative stress, an environmental stimulus that potentially suppresses USP8 activity, induced accumulation of K63-linked ubiquitin chains on endosomes, recruitment of TAB2, and expression of the inflammatory cytokine. The results demonstrate that USP8 is a gatekeeper of misdirected ubiquitin signals and inhibits immune and stress response pathways by removing K63-linked ubiquitin chains from endosomes.

Inhibition of cysteine protease disturbs the topological relationship between bone resorption and formation in vitro

INTRODUCTION

Osteoporosis is a global health issue. Bisphosphonates that are commonly used to treat osteoporosis suppress both bone resorption and subsequent bone formation. Inhibition of cathepsin K, a cysteine proteinase secreted by osteoclasts, was reported to suppress bone resorption while preserving or increasing bone formation. Analyses of the different effects of antiresorptive reagents such as bisphosphonates and cysteine proteinase inhibitors will contribute to the understanding of the mechanisms underlying bone remodeling.

MATERIALS AND METHODS

Our team has developed an in vitro system in which bone remodeling can be temporally observed at the cellular level by 2-photon microscopy. We used this system in the present study to examine the effects of the cysteine proteinase inhibitor E-64 and those of zoledronic acid on bone remodeling.

RESULTS

In the control group, the amount of the reduction and the increase in the matrix were correlated in each region of interest, indicating the topological and quantitative coordination of bone resorption and formation. Parameters for osteoblasts, osteoclasts, and matrix resorption/formation were also correlated. E-64 disrupted the correlation between resorption and formation by potentially inhibiting the emergence of spherical osteoblasts, which are speculated to be reversal cells in the resorption sites.

CONCLUSION

These new findings help clarify coupling mechanisms and will contribute to the development of new drugs for osteoporosis.

Glomeruli Count and Arterial Injury in Real-Time Ultrasound-Guided Needle Kidney Biopsy Specimens: Adequacy of Three Approaches for Pig Kidneys

INTRODUCTION

Real-time ultrasound-guided percutaneous kidney biopsy is essential for diagnosis and treatment planning; nonetheless, the optimal puncture approach has yet to be established. In vivo, performing different approaches on the same patient at once is not possible. This study aimed to determine the impact of different approaches on the number of obtained glomeruli and their potential to cause arterial injury using pig kidneys, which are similar to humans.

METHODS

A total of 120 pig kidneys (60 right-sided kidneys and 60 left-sided kidneys) for research were obtained from a slaughterhouse. The specimens were collected from the lower pole on the sagittal plane of the kidney using three different approaches on the same kidney: caudocranial approach, caudal to cranial; craniocaudal approach, cranial to caudal; and vertical approach, through the surface cortex. Five blinded pediatric nephrologists assessed the number of glomeruli and arterial injuries.

RESULTS

Overall, 360 specimens were collected from the kidneys through biopsy using a 16-gauge needle (mean vertical kidney length, 11.2 ± 0.7 cm; mean depth, 3.47 ± 0.23 cm). No significant difference in the incidence of arterial injury was observed between the three approaches (caudocranial vs. craniocaudal vs. vertical approaches: 78% vs. 87% vs. 87%, p = 0.14). In contrast, the vertical approach retrieved significantly more glomeruli than the caudocranial and craniocaudal approaches (caudocranial approach: 7.5 ± 2.8, craniocaudal approach: 7.8 ± 2.7, and vertical approach: 8.9 ± 3.3, p < 0.001).

CONCLUSIONS

Considering its efficacy and safety profile, the vertical approach may be preferred, as more glomeruli can be obtained without increasing the incidence of arterial injury. Although the results cannot be directly extrapolated to humans due to the differences between species, they still offer important insights into the characteristics of each approach.

A Case of Shear Wave Velocity Reflecting the Disease Activity in Glomerulonephritis

Ultrasound elastography can measure tissue elasticity using the shear wave velocity (SWV). Evaluating disease activity with elastography instead of renal biopsy may be less invasive. However, to the best of our knowledge, although there are studies comparing different glomerular diseases using SWV, there are no reports that have measured glomerulonephritis longitudinally from the acute phase of the disease. This study aimed to assess whether SWV reflects disease activity in glomerulonephritis, and we continued to observe children with post-streptococcal acute glomerulonephritis (PSAGN) from the acute phase to over a year later. In this case, a 6-year-old boy diagnosed with PSAGN had impaired renal function, and was admitted and tested. He was placed in a prone resting position and measurements were taken from the back. SWV was measured ≥50 times at each examination, and the mean was calculated when the net amount of effective SWV was ≥50%. The tests were performed once in the acute phase and thrice during the recovery phase for 13 months. SWV was found to be significantly lower in the recovery period than during the disease onset, and continued to stay lower at each test during the recovery period (P < 0.02). In conclusion, this indicated that SWV fluctuated similarly to the disease activity of glomerulonephritis; therefore, we suggest using SWV measurement to estimate the disease activity in glomerulonephritis in children. Although more clinical cases are needed, SWV measurement is a noninvasive and reproducible imaging modality to estimate the disease activity in glomerulonephritis.

Late-gestation prediction of outcome in tricuspid valve dysplasia and Ebstein's anomaly using fetal tricuspid regurgitation waveform analysis

OBJECTIVE

To investigate the criteria, based on fetal TR waveforms in late gestation, to predict biventricular circulation (BV) after birth in cases of tricuspid valve dysplasia (TVD) or Ebstein's anomaly diagnosed during the fetal period.

METHODS

We included 35 consecutive cases diagnosed with TVD or Ebstein's anomaly during the fetal period between January 2008 and December 2021 at Kanagawa Children's Medical Center, Kanagawa, Japan. The maximum velocity and change in pressure over time of tricuspid regurgitation (TR) jet (dP/dt), estimated using TR waveforms obtained during the late-gestation period (gestational age ≥ 28 weeks), were collected from patient records. dP/dt was calculated by dividing the change in estimated right ventricular pressure obtained using Bernoulli's principle by the time taken for the TR maximum velocity to change from one-third to two-thirds of its peak value. The outcome was divided into four categories: BV, single ventricular circulation, neonatal death and fetal death. Patients with BV were included in the BV group, while patients with single ventricular circulation, neonatal death or fetal death were included in the non-BV (NBV) group.

RESULTS

Overall, 19 and 16 patients were included in the BV and NBV groups, respectively. The median TR maximum velocity was 3.3 (range, 2.4-3.6) m/s in the BV group and 1.9 (range, 1.0-3.3) m/s in the NBV group. There were no cases of postnatal BV in fetuses with TR maximum velocity < 2.4 m/s; cases with TR maximum velocity of 2.4-3.3 m/s were observed in both BV and NBV groups. Receiver-operating-characteristics-curve analysis was performed on the 11 patients in the BV group and five patients in the NBV group with a TR maximum velocity of 2.4-3.3 m/s. dP/dt ≥ 350 mmHg/s and TR maximum velocity ≥ 2.9 m/s were identified as criteria for predicting the outcome in such cases. The performance of dP/dt ≥ 350 mmHg/s in predicting BV after birth in fetuses with TVD or Ebstein's anomaly was higher compared to that of TR maximum velocity ≥ 2.9 m/s (sensitivity, 90.9% vs 72.3% and specificity, 80.0% vs 80.0%, respectively).

CONCLUSIONS

In fetuses with TVD or Ebstein's anomaly, the postnatal outcome may be BV or NBV when the TR maximum velocity is 2.4-3.3 m/s. In such cases, by combining the TR maximum velocity with dP/dt ≥ 350 mmHg/s, BV after birth may be predicted with greater accuracy. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Clinical characteristics and outcomes of pheochromocytoma crisis: a literature review of 200 cases

PURPOSE

Pheochromocytoma crisis is a life-threatening endocrine emergency that requires prompt diagnosis and treatment. Because of its rarity, sudden onset, and lack of internationally uniform and validated diagnostic criteria, pheochromocytoma crisis remains to be fully clarified. Therefore, we aimed to describe the clinical characteristics and outcomes of pheochromocytoma crisis through a literature review.

METHODS

We performed a systematic literature search of PubMed/MEDLINE database, Igaku-Chuo-Zasshi (Japanese database), and Google Scholar to identify case reports of pheochromocytoma crisis published until February 5, 2021. Information was extracted and analyzed from the literature that reported adequate individual patient data of pheochromocytoma crisis in English or Japanese. Cases were also termed as pheochromocytoma multisystem crisis (PMC) if patients had signs of hyperthermia, multiple organ failure, encephalopathy, and labile blood pressure.

RESULTS

In the 200 cases of pheochromocytoma crisis identified from 187 articles, the mean patient age was 43.8 ± 15.5 years. The most common symptom was headache (39.5%). The heart was the most commonly damaged organ resulting from a complication of a pheochromocytoma crisis (99.0%), followed by the lungs (44.0%) and the kidney (21.5%). PMC accounted for 19.0% of all pheochromocytoma crisis cases. After excluding 12 cases with unknown survival statuses, the mortality rate was 13.8% (26/188 cases). Multivariable logistic regression analysis revealed that nausea and vomiting were significantly associated with a higher mortality rate.

CONCLUSION

Pheochromocytoma can present with different symptomatology, affecting different organ systems. Clinicians should be aware that patients with nausea or vomiting are at a higher risk of death because of pheochromocytoma crisis.

Congenital venous anomalies associated with retrocaval ureter: evaluation using computed tomography

BACKGROUND

Retrocaval ureter is a rare congenital anomaly resulting from anomalous development of inferior vena cava (IVC) and not from anomalous of the ureter. The anomaly always occurs on the right side due to regression of right supracardinal vein and persistence of right posterior cardinal vein. Retrocaval ureter tends to be associated with various vena cava anomalies because of the embryogenesis. We aimed to identify the prevalence of associated congenital venous anomalies (CVA) resulting from cardinal vein development in adults with retrocaval ureter using computed tomography (CT) images.

MATERIALS AND METHODS

The study included 22 adults with retrocaval ureter. We evaluated CT findings and determined the incidence of associated CVA using thin slice data sets from CT scanner with 64 or more detectors. We compared the prevalence of CVA in the retrocaval ureter group (mean age: 57±19 years) and in the control group of 6189 adults with normal ureter (mean age: 66±14 years).

RESULTS

In the retrocaval ureter group, 4 adults (18.2 %) had CVA including double IVC, right double IVC, preisthmic IVC with horseshoe kidney, and preaortic iliac confluence. One of 2 adults with preaortic iliac confluence had right double right IVC. In the control group, 49 adults (0.79%) had CVA including 37 double IVCe, 11 left IVCe, and 1 IVC interruption azygos continuation. Fifteen horseshow kidneys were found. The prevalence of associated CVA in the retrocaval ureter group was higher than that in the control group (p<0.001).

CONCLUSIONS

Retrocaval ureter is frequently associated with CVA. Various CVA with retrocaval ureter could happen because of abnormal development of not only the right posterior or supra cardinal vein but also other cardinal veins.

Fluctuation of R2* values in blood oxygenation level-dependent MRI during acute and remission phases of IgA vasculitis with nephritis in children

PURPOSE

Noninvasive assessment of the kidney using blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) has progressed remarkably; indications have expanded to include the evaluation of glomerulonephritis. However, no longitudinal measurements from acute to post-treatment remission phases have been reported. Hence, this study aimed to investigate spin relaxation rate (R2*) values during acute and remission phases in children with glomerulonephritis.

MATERIALS AND METHODS

All pediatric patients with IgA vasculitis with nephritis (IgAVN) diagnosed between January 2014 and October 2021 and requiring renal biopsy were retrospectively reviewed; four patients who were observed from onset to remission were included in this study. In total, eight MRIs were performed in the acute and remission phases, and R2* values and fluctuations induced by low-dose oxygen administration were determined from 10 echoes using a 1.5 T MRI system with 4.76-47.6 ms echo times and a 153 ms repetition time.

RESULTS

The median age of patients undergoing MRI was 8.5 years in the acute phase and 13.9 years in the remission phase. R2* values of the acute phase were higher than those of the remission phase; however, the difference was not significant (cortex; p = 0.32 and medulla; p = 0.052). Oxygen administration did not cause fluctuations in the R2* values in the cortex or medulla during the acute phase (cortex; p = 0.67 and medulla; p = 0.76); however, in the remission phase, the R2* values in the cortex and medulla significantly decreased due to low-dose oxygen administration (cortex; p < 0.01 and medulla; p < 0.01).

CONCLUSION

The fluctuation in R2* values observed during different phases of IgAVN indicates that BOLD MRI may be used to assess disease activity. Therefore, we propose BOLD MRI with low-dose oxygen administration as a noninvasive method to evaluate the activity of glomerulonephritis.

Effects of diurnal variation of bile acids by meal on cyclosporine A absorption

BACKGROUND

Stabilizing blood levels with microemulsified cyclosporine A (CsA), administered in many pediatric kidney diseases, is important for effective immunosuppression and reduced nephrotoxicity. CsA is affected by total bile acids (TBAs); however, no reports have simultaneously measured both. We aimed to elucidate the hypothesized relationship between TBA levels and diurnal variation in CsA in children.

METHODS

We retrospectively reviewed the medical records of children who were taking oral CsA for the treatment of kidney diseases between January 2016 and July 2021. They consumed four balanced meals and snacks during the day. CsA and TBA were measured twice, in pairs, before and at 0.5, 1, 1.5, 2, 3, and 4 h after oral administration in the morning and evening, and the four-h area under curve (AUC)_0-4 of CsA and trough-to-peak ratio (TPR) of TBA were compared.

RESULTS

Fifty-eight pairs were measured in total; 12 children had idiopathic nephrotic syndrome and 4 children had immunoglobulin A vasculitis with nephritis. The median age at measurement was 7.5 years and the dose of CsA was 3.8 mg/kg/day. The AUC_0-4 (ng·h/mL) was significantly lower in the evening than in the morning (1,669 vs. 1,451, P < 0.001). The TPR of TBA was significantly higher in the evening than in the morning (0.14 vs. 0.25, P < 0.001).

CONCLUSIONS

The low AUC_0-4 and slow TBA secretion observed in the evening may be due to pediatric-specific dietary rhythms; thus, snack timing should be considered in children for stabilizing CsA levels.

Calculation of an Enhanced A_{1g} Symmetry Mode Induced by Higgs Oscillations in the Raman Spectrum of High-Temperature Cuprate Superconductors

In superconductors the Anderson-Higgs mechanism allows for the existence of a collective amplitude (Higgs) mode which can couple to eV light mainly in a nonlinear Raman-like process. The experimental nonequilibrium results on isotropic superconductors have been explained going beyond the BCS theory including the Higgs mode. Furthermore, in anisotropic d-wave superconductors strong interaction effects with other modes are expected. Here we calculate the Raman contribution of the Higgs mode from a new perspective, including many-body Higgs oscillations effects and their consequences in conventional, spontaneous Raman spectroscopy. Our results suggest a significant contribution to the intensity of the A_{1g} symmetry Raman spectrum in d-wave superconductors. In order to test our theory, we predict the presence of measurable characteristic oscillations in THz quench-optical probe time-dependent reflectivity experiments.

Cyclosporine A C1.5 monitoring reflects the area under the curve in children with nephrotic syndrome: a single-center experience

BACKGROUND

The currently used single-monitoring method for drug-blood-level evaluation in cyclosporine A (CsA) treatment for nephrotic syndrome (NS) was established through hourly measurements based on adult organ transplantation. However, the pharmacokinetics may differ due to different concomitant medications, age, and conditions. This study was conducted to determine the measurement timing that best reflects the CsA area under the curve (AUC) in pediatric NS.

METHODS

This retrospective study included children aged 2-14 years who were started on CsA treatment for idiopathic NS during 2013-2020. AUC_0-4 was calculated from 7 points, before and 0.5, 1, 1.5, 2, 3, and 4 h after administration. Mean values at each timing were compared with age-dependent different drug forms. Correlation between AUC_0-4 and measurement timing was analyzed.

RESULTS

There were 13 patients (11 boys) whose median age during testing was 7.3 years, and the total number of measurements was 94. The highest timing of CsA concentrations was found in C₁ 59.6%. The content liquid used at younger ages had a faster absorption time to peak value and lower blood concentration than those of capsules. Among the significant correlations observed, AUC_0-4 and C_1.5 showed the strongest significant correlation coefficient (r = 0.93, P < 0.001).

CONCLUSION

In pediatric NS, CsA metabolism may be faster than that in previous organ transplantation. Compared with C₂, C_1.5 monitoring may result in better disease control as it can best reflect the AUC_0-4 and peak values associated with side effects, which are indicators of therapeutic efficacy.

Dopaminergic restoration of prefrontal cortico-putaminal network in gene therapy for aromatic l-amino acid decarboxylase deficiency

Aromatic l-amino acid decarboxylase (AADC) is an essential dopamine-synthesizing enzyme. In children with AADC deficiency, the gene delivery of AADC into the putamen, which functionally interacts with cortical regions, was found to improve motor function and ameliorate dystonia. However, how the restoration of dopamine in the putamen in association with cortico-putaminal networks leads to therapeutic effects remains unclear. Here, we examined neuroimaging data of eight patients with AADC deficiency (five males and three females, age range 4-19 years) who received the AADC gene therapy of the bilateral putamen in an open-label phase 1/2 study. Using high-resolution positron emission tomography with a specific AADC tracer, 6-[¹⁸F]fluoro-l-m-tyrosine (FMT), we showed that FMT uptake increased in the broad area of the putamen over the years. Then, with the structural connectivity-based parcellation of the putaminal area, we found that motor improvement is associated with dopaminergic restoration of the putaminal area that belongs to the prefrontal cortico-putaminal network. The prefrontal area dominantly belongs to the frontoparietal control network, which contributes to cognitive-motor control function, including motor initiation and planning. The results suggest that putaminal dopamine promotes the development of an immature motor control system, particularly in the human prefrontal cortex that is primarily affected by AADC deficiency.

P–192 Efficacy of postponement of intracytoplasmic sperm injection timing after spindle visualization for Metaphase I oocytes

Study question

Does postponement of intracytoplasmic sperm injection (ICSI) timing after spindle visualization for Metaphase I (MI) oocytes improve developmental outcomes of embryos?

Summary answer

Postponement of ICSI timing after spindle visualization for MI oocytes improves blastocyst utility rates.

What is known already

Immature oocytes are generally considered poor developmental outcomes. Meanwhile, the timing of ICSI adjusted by using spindle visualization can improve clinically utilized embryos and live birth rates, but these outcomes remain inferior to those of mature oocytes. In in vitro maturation culture, nuclear maturation is thought to occur before the completion of cytoplasmic maturation, and in immature oocytes, synchronization of nuclear and cytoplasmic maturation may be insufficient for ICSI immediately after spindle visualization.

Study design, size, duration

Data for this retrospective cohort study were obtained 672 oocytes retrieved under mild stimulation cycles using letrozole, in patients aged younger than 39 years between April 2017 and October 2020.Written informed consent was obtained from all patients. This study was approved by the institutional review board.

Participants/materials, setting, methods

As a control group, 464 MetaphaseIIoocytes that underwent ICSI immediately after visualization of the spindle were used. In group A, 103 MI oocytes underwent ICSI immediately after the first polar body release and spindle visualization, and in group B, 105 oocytes underwent ICSI 2–3 hours after spindle visualization. The primary outcomes were fertilization rates, degeneration, cleavage, embryo blastocyst formation, and utility rates. Outcomes were compared among the three groups.

Main results and the role of chance

The baseline fertilization rates of each group (control, A, B) were 82.3% (382/464), 73.8% (76/103), and 83.8% (88/105), respectively. The rate was significantly lower in group A than in the control group (P &lt; 0.05), and also tended to be lower in group A than in group B, although the difference was not significant. There was no significant difference in abnormal fertilization rates, oocyte degeneration rates, cleavage rates, and blastocyst formation rates among the three groups. [control, A, B: abnormal fertilization rate: 4.3% (20/464), 8.7% (9/103), 4.8% (5/105); oocyte degeneration rates: 3.0% (14/464), 1.9% (2/103), 3.8% (4/105); cleavage rates: 95.6% (307/321), 93.8% (61/65), 98.7% (74/75); blastocyst formation rates: 58.6% (177/302), 51.7% (31/60), 55.4% (41/74), respectively]. The blastocyst utility rates of control group and group B were significantly higher than in group A [41.7% (126/302), 45.9% (34/74), 26.7% (16/60), respectively] (P &lt; 0.05). There were no significantly different outcomes between the control group and group B.

Limitations, reasons for caution

The optimal timing of ICSI for MI oocyte cannot be determined by the presence or absence of spindles. In addition, the postponement duration we set was based on reports which reported on final oocyte maturation, and further investigation is needed to establish the optimal ICSI timing for MI oocytes.

Wider implications of the findings: In MI oocytes, postponement of ICSI timing after spindle visualization is essential for synchronization of the nucleus and cytoplasmic maturation.

Trial registration number

none

P–609 The chances of one live birth rates after first ART cycle in minimal stimulation cycle IVF with letrozole only and natural cycle IVF

Study question

Are one live birth rates (LBRs) similar in minimal stimulation cycle IVF with letrozole only and natural cycle IVF for the first ART cycle?

Summary answer

LBRs after first ART cycle in minimal stimulation cycle IVF with letrozole only are superior to natural cycle IVF.

What is known already

The addition of letrozole to gonadotropins in ovarian stimulation (OS) may reduce the risk of OHSS, but there is no significant difference were reported in ongoing pregnancy rate or number of oocytes retrieved in the letrozole + FSH group compared to the FSH only. No differences were also reported in clinical pregnancy rates or number of mature oocytes in the additional of letrozole in an GnRH antagonist protocol group compared to the GnRH antagonist group. There are no previous study comparing LBRs after first ART cycle in minimal stimulation cycle IVF with letrozole and natural cycle IVF.

Study design, size, duration

Data for this retrospective cohort study were obtained 643 women, 30–39 years of age started their first ART cycle at one private fertility clinic between January 2016- December 2019.

Participants/materials, setting, methods

A total of 643 women were scheduled their first oocyte retrieval cycle. 118 women started with letrozole (LE) and 525 women started natural cycle (NC). The main strategy for OS in our center is minimal stimulation and natural cycle IVF. Patients consulted with gynecologists to determine their treatment plan based on patients’ preference or their menstrual cycle. All pregnancies generated from oocyte retrieval during the first IVF cycle including fresh and frozen-thaw cycles were registered.

Main results and the role of chance

The number of retrieved oocytes and the normal fertilization rates were significantly higher in the LE than NC (4.4 vs 3.4, 77.6% vs 71.1%), p &lt; 0.05 respectively). There was no significant difference in the clinical pregnancy rates (CPRs) per embryo transfer (ET) (fresh cleavage stage ET: 32.9% vs 28.0%, frozen-thaw blastocyst ET: 39.4% vs 44.9% ns). However, the CPRs and LBRs per oocyte retrieval (OR) were significantly higher in the LE group (39.0% vs 28.6, 33.9% vs 21.9%, p &lt; 0.05 respectively). In a subsequent regression analyses, LBRs per OR of LE was significantly higher than NC as well. (adjusted OR = 1.63 (95% CI: 1.02–2.58, p = 0.041).

Limitations, reasons for caution

The strength of the present study was the use of a large cohort of women who underwent minimal stimulation IVF with letrozole only. Although our results are promising, limited by retrospective cohort study. These interpretations prompted the need for a perspective cohort study to evaluate the efficacy of letrozole.

Wider implications of the findings: When comparing minimal stimulation IVF with letrozole only and natural cycle IVF, we found significantly higher LBRs per OR in minimal stimulation IVF with letrozole only, despite similar CPRs per ET.

Trial registration number

none

Impaired Consciousness in a Coronavirus Disease 2019 Patient Caused by Low Serum Sodium: A Case Report

A 30 year-old man with a high fever (37.5°C-40°C), vomiting, slurred speech, and mild cognitive impairment was admitted to our Emergency Department. He had traveled from Spain to the UK on business at the end of February 2020. A nasopharyngeal swab was positive by RT-PCR for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but a cerebrospinal fluid (CSF) sample was negative. His neurological abnormalities recovered completely on saline infusion to normalize his low serum sodium level. Although neurological abnormalities in patients with COVID-19 are rare, it is important to distinguish the etiologies including encephalitis, meningitis, or merely electrolyte abnormalities.

FRI0172 THE INFLUENCE OF CALCINEURIN INHIBITORS ON DEVELOPMENT OF CANCER IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS: A RETROSPECTIVE OBSERVATIONAL STUDY IN THE LUNA REGISTRY

Background:

It has been reported that the incidence of cancer in patients with systemic lupus erythematosus (SLE) is higher than that in healthy individuals, but the findings are inconsistent1. In the transplantation field, a few studies indicated an association between the use of immunosuppressants and an increased risk of cancer2. Calcineurin inhibitors (CNIs), which include cyclosporine and tacrolimus, have been used for >30 years to treat renal and extrarenal manifestations of SLE, but the effects of exposure to CNIs among SLE patients have not been established.

Objectives:

We investigated the incidence of various cancers (including cervical dysplasia) among SLE patients registered in the LUpus registry of NAtionwide institution (LUNA). We also investigate whether the registrants’ exposure to CNIs increased the risk of cancer.

Methods:

We calculated the standardized incidence ratio (SIR) of cancer among SLE patients based on the age-standardized incidence rate of cancer reported by Japan’s Ministry of Health, Labour and Welfare. A multivariate analysis of the risk of cancer was performed using the covariates of age, smoking history, CNI treatment history, maximum steroid dose in the past, and Systemic Lupus International Collaboration Clinics/American College of Rheumatology Damage Index [SDI]) value (excluding the occurrence of cancer) at the time of the patient’s registration.

Results:

We studied 714 patients (663 females; 88.9%).The median age at registry was 44 [interquartile range (IQR): 35–56] years. The median past max. steroid dose was 40 mg/day (IQR: 30–60 mg/day), and the SDI at registration was 1 (IQR 0–2). Smoking history was present in 248 patients (34.9%), and 53 patients (7.4%) experienced cancer complications. Gynecologic malignancies accounted for 71% of all cancers, including 12 cervical dysplasia cases. The standardized incidence rate of cancer in these SLE patients was 1.46 (95%CI: 1.07–1.85, p<0.01). The multivariate analysis showed that a CNI treatment history was not a risk factor for the development of cancer (OR 1.76, 95%CI: 0.63–4.88, p=0.30). After the covariance was adjusted for the propensity score, the risk of cancer in the CNIs group was not increased compared to the non-CNIs group (adjusted OR 2.46, 95%CI: 0.68–8.91, p=0.20).

Conclusion:

The incidence of cancer in SLE was higher in the LUNA cohort than in the general population. Our results suggest that CNI treatment for individuals with SLE is not a risk factor for the development of cancer.

References:

[1]Ladouceur A. et.al, Expert Rev Clin Immunol. 2018 Oct;14(10):793-802.

[2]Gutierrez-Dalmau A. et.al, Drugs 2007;67(8):1167-98.

Disclosure of Interests:

None declared

AB0387 TREATMENT STATUS FOR OSTEOPOROSIS IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS: CROSS-SECTIONAL ANALYSIS FROM A LUPUS REGISTRY OF NATIONWIDE INSTITUTIONS (LUNA)

Background:

Osteoporosis is one of the most important adverse effects of glucocorticoids in patients with systemic lupus erythematosus (SLE). Because osteoporosis is accelerated by chronic kidney disease (CKD), more attention should be paid to the treatment for osteoporosis in SLE patients with CKD. Many treatment options for osteoporosis have emerged recently, but treatment status in patients with SLE is not elucidated.

Objectives:

The purpose of this study is to elucidate the treatment status for osteoporosis in patients with SLE among the CKD stages.

Methods:

Using data from lupus registry of nationwide institutions (LUNA), a cross-sectional analysis was performed. We firstly described treatment status for osteoporosis in all enrolled patients. Secondary, treatment status for osteoporosis was compared among CKD stages. Finally, bone damage in Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) was compared among CKD stages.

Results:

The median age (interquartile range [IQR]) of enrolled 917 patients was 44 (34- 57) years and 809 patients (88%) were female. CKD stages were follows: CKD stage 1, 234 (26%); CKD stage 2, 465 (51%); CKD stage 3, 189 (21%); CKD stage 4, 9 (1%); CKD stage 5, 16 (2%). Median (IQR) age, female sex, and median (IQR) previous maximum dose of prednisolone in patients with and without CKD (≥CKD stage 3) were 56 (46.5-66) and 41 (32-50), 191 (89%) and 615 (88%), and 40 (30-60) and 40 (30-55) mg/day, respectively. Bisphosphonate was administered in 388 (42%) patients, vitamin D supplements in 448 (49%), Ca supplements in 36 (4%), denosumab in 20 (2%) and teriparatide in 14 (2%), respectively. Of enrolled patients, any treatment for osteoporosis was not administered in 226 (25%) patients. In spite of more frequent bone damage in patients with CKD compared to those without CKD (15% vs 10%, p=0.036), treatment status did not differ between patients with and without CKD (bisphosphonate: 41% vs 46%, p=0.29; vitamin D supplements: 50% vs 44%, p=0.14).

Conclusion:

About a quarter of patients with SLE did not take any treatment for osteoporosis. Treatment for osteoporosis might be strengthened to prevent bone damage in SLE patients with CKD.

Disclosure of Interests:

KEN-EI SADA Speakers bureau: I received speaker’s fee from GSK and Astra Zeneca K.K., Keigo Hayashi: None declared, Yosuke ASANO: None declared, Yu Katayama: None declared, Sumie Hiramatsu Asano: None declared, Keiji Ohashi: None declared, Michiko Morishita: None declared, Haruki Watanabe: None declared, Mariko Narazaki: None declared, Yoshinori Matsumoto: None declared, Nobuyuki Yajima: None declared, Ryusuke Yoshimi: None declared, Yasuhiro Shimojima: None declared, Shigeru Ono: None declared, Hiroshi Kajiyama: None declared, Kunihiro Ichinose: None declared, Shuzo Sato: None declared, Michio Fujiwara: None declared, Jun Wada: None declared

AB0413 INVESTIGATION OF THE ASSOCIATION OF CARDIOVASCULAR EVENTS AND ANTI- SS-A ANTIBODIES AS RISK OF DEVELOPMENT IN PATIENTS WITH LUPUS NEPHRITIS FROM THE LUNA REGISTRY: A CROSS-SECTIONAL STUDY

Background:

Cardiovascular disease(CVD) has been identified as a major cause of morbidity and mortality in patients with lupus nephritis(LN)1) 2). There is a clear causal relationship between the onset of neonatal lupus (cardiac complications) and SS-A antibodies3) 4), but no association has been reported in adults. In recent years, there have been reports from overseas that suggest the association between CVD and anti-SS-A antibody in adult systemic lupus erythematosus (SLE) patients5) 6). So far, no studies have not been reported to evaluate the relationship between anti-SS-A antibody and the risk of developing CVD in LN in a large cohort of patients with SLE in Japan.

Objectives:

The aim of this study was to evaluate the association between anti-SS-A antibody and the risk of developing CVD in LN patients using a multicenter registration study [Lupus registry of nationwide institution (LUNA)] in Japan.

Methods:

We identified 931 patients diagnosed with SLE in the Lupus registry of nationwide institution (LUNA), and further identified 275 LN patients with known the presence or absence of both development of CVD and presence of anti-SS-A antibody. We defined the exposure factor as anti-SS-A antibody, and the outcome as CVD. SELENA-SLEDAI score (at diagnosis), eGFR <60%, HbA1c, BMI, and steroid pulse treatment history were used as confounding factors and we analyzed using logistic regression analysis.

Results:

We found 68 patients (24.7%) complicated with CVD, including percarditis (7.3%), cerebrovascular disorder (6.2%), peripheral Arterial Disease (6.2%), Ischemic heart disease (2.9%),venous thromboembolism (2.9%),pulmonary hypertension (1.5%), vulvular heart disease (1.1%), and cardiomyopathy (0.4%). In univariate analysis, there was no significant difference in the occurrence of CVD depending on the presence or absence of anti-SS-A antibody (p = 0.32), and the results of multivariate analysis showed no significant difference in anti-SS-A antibody [p = 0.23, odds: 0.41, 95% confidence interval (0.09-1.89)].

Conclusion:

The association between anti-SS-A antibody and the development of CVD in LN patients in Japan has not been identified.

References:

[1]Lupus. 2000;9(3):166-9

[2]Arthritis Rheum.2019 Mar;71(3):403-410,

[3]J Intern Med 265:653-662, 2009

[4]Nat Clin Pract Rheumatol 5:139-148, 2009

[5]Ann Rheum Dis 1990;49:627-629

[6]Chest. 2018 Jan;153(1):143-151. Doi:

Disclosure of Interests:

None declared

Author Correction: Forearc carbon sink reduces long-term volatile recycling into the mantle

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

P6415Combined assessment of contrast-enhanced ultrasound of carotid plaque and carotid intima-media thickness improves the prediction of future coronary events in patients with coronary artery disease

Background

This study examined whether combined ultrasound assessment of plaque size and intraplaque neovascularization in the carotid artery had an additive effect for predicting coronary events in patients with coronary artery disease (CAD).

Methods

CEUS of the carotid plaques using perfluorobutane microbubbles as an ultrasound contrast agent and Ultrasound assessment of carotid plaque maximum intima-media thickness (max IMT) was performed in 221 patients with CAD and carotid plaque IMT over 2mm. Intraplaque neovascularization was identified on the basis of microbubbles within the carotid plaque and graded as: G0, not visible; G1, moderate; or G2, extensive microbubbles. All study patients were followed up prospectively for 5 years or until the occurrence of a cardio-vascular event.

Result

During the follow-up period, 53 coronary events (9 cardiac deaths, 44 ACSs) were occurred. Multivariate Cox hazards analysis showed that max IMT and CEUS grade were independent predictors of coronary events (HR 1.59, 95% CI 1.15–2.21 p=0.005 and HR 2.26, 95% CI 1.52–3.36 p<0.01) that were independent of age, gender, diabetes and LDL-C levels. C-statistics for logistic models predicting future coronary events using conventional risk factors with or without the addition of max IMT alone, CEUS grade alone, and both max IMT and CEUS grade in combination (area under the ROC curve; 0.55,0.61,0.69 and 0.71, respectively). The addition of the plaque enhanced intensity to traditional risk factors resulted in net reclassification improvement (NRI) and integrated discrimination improvement (IDI) (NRI 0.42, p=0.002; and IDI 0.04, p=0.002).

CEUS grade and ROC curve for 3models

Conclusions

Combined ultrasound assessment of carotid plaque IMT and intraplaque neovascularization has an additive value on the prediction of coronary events.

Gene therapy improves motor and mental function of aromatic l-amino acid decarboxylase deficiency

In patients with aromatic l-amino acid decarboxylase (AADC) deficiency, a decrease in catecholamines and serotonin levels in the brain leads to developmental delay and movement disorders. The beneficial effects of gene therapy in patients from 1 to 8 years of age with homogeneous severity of disease have been reported from Taiwan. We conducted an open-label phase 1/2 study of population including adolescent patients with different degrees of severity. Six patients were enrolled: four males (ages 4, 10, 15 and 19 years) and one female (age 12 years) with a severe phenotype who were not capable of voluntary movement or speech, and one female (age 5 years) with a moderate phenotype who could walk with support. The patients received a total of 2 × 10¹¹ vector genomes of adeno-associated virus vector harbouring DDC via bilateral intraputaminal infusions. At up to 2 years after gene therapy, the motor function was remarkably improved in all patients. Three patients with the severe phenotype were able to stand with support, and one patient could walk with a walker, while the patient with the moderate phenotype could run and ride a bicycle. This moderate-phenotype patient also showed improvement in her mental function, being able to converse fluently and perform simple arithmetic. Dystonia disappeared and oculogyric crisis was markedly decreased in all patients. The patients exhibited transient choreic dyskinesia for a couple of months, but no adverse events caused by vector were observed. PET with 6-[¹⁸F]fluoro-l-m-tyrosine, a specific tracer for AADC, showed a persistently increased uptake in the broad areas of the putamen. In our study, older patients (>8 years of age) also showed improvement, although treatment was more effective in younger patients. The genetic background of our patients was heterogeneous, and some patients suspected of having remnant enzyme activity showed better improvement than the Taiwanese patients. In addition to the alleviation of motor symptoms, the cognitive and verbal functions were improved in a patient with the moderate phenotype. The restoration of dopamine synthesis in the putamen via gene transfer provides transformative medical benefit across all patient ages, genotypes, and disease severities included in this study, with the most pronounced improvements noted in moderate patients.

Improvement of driver active interventions during automated driving by displaying trajectory pointers-A driving simulator study

Objective: The handover of vehicle control from automated to manual operation is a critical aspect of interaction between drivers and automated driving systems (ADS). In some cases, it is possible that the ADS may fail to detect an object. In this event, the driver must be aware of the situation and resume control of the vehicle without assistance from the system. Consequently, the driver must fulfill the following 2 main roles while driving: (1) monitor the vehicle trajectory and surrounding traffic environment and (2) actively take over vehicle control if the driver identifies a potential issue along the trajectory. An effective human-machine interface (HMI) is required that enables the driver to fulfill these roles. This article proposes an HMI that constantly indicates the future position of the vehicle. Methods: This research used the Toyota Dynamic Driving Simulator to evaluate the effect of the proposed HMI and compares the proposed HMI with an HMI that notifies the driver when the vehicle trajectory changes. A total of 48 test subjects were divided into 2 groups of 24: One group used the HMI that constantly indicated the future position of the vehicle and the other group used the HMI that provided information when the vehicle trajectory changed. The following instructions were given to the test subjects: (1) to not hold the steering wheel and to allow the vehicle to drive itself, (2) to constantly monitor the surrounding traffic environment because the functions of the ADS are limited, and (3) to take over driving if necessary. The driving simulator experiments were composed of an initial 10-min acclimatization period and a 10-min evaluation period. Approximately 10 min after the start of the evaluation period, a scenario occurred in which the ADS failed to detect an object on the vehicle trajectory, potentially resulting in a collision if the driver did not actively take over control and manually avoid the object. Results: The collision avoidance rate of the HMI that constantly indicated the future position of the vehicle was higher than that of the HMI that notified the driver of trajectory changes, χ² = 6.38, P < .05. The steering wheel hands-on and steering override timings were also faster with the proposed HMI (t test; P < .05). Conclusions: This research confirmed that constantly indicating the position of the vehicle several seconds in the future facilitates active driver intervention when an ADS is in operation.

Preoperative oral care and effect on postoperative complications after major cancer surgery

Background

Improving patients' oral hygiene is an option for preventing postoperative pneumonia that may be caused by aspiration of oral and pharyngeal secretions. Whether preoperative oral care by a dentist can decrease postoperative complications remains controversial. A retrospective cohort study was undertaken to assess the association between preoperative oral care and postoperative complications among patients who underwent major cancer surgery.

Methods

The nationwide administrative claims database in Japan was analysed. Patients were identified who underwent resection of head and neck, oesophageal, gastric, colorectal, lung or liver cancer between May 2012 and December 2015. The primary outcomes were postoperative pneumonia and all-cause mortality within 30 days of surgery. Patient background was adjusted for with inverse probability of treatment weighting using propensity scoring.

Results

Of 509 179 patients studied, 81 632 (16·0 per cent) received preoperative oral care from a dentist. A total of 15 724 patients (3·09 per cent) had postoperative pneumonia and 1734 (0·34 per cent) died within 30 days of surgery. After adjustment for potential confounding factors, preoperative oral care by a dentist was significantly associated with a decrease in postoperative pneumonia (3·28 versus 3·76 per cent; risk difference − 0·48 (95 per cent c.i. −0·64 to−0·32) per cent) and all-cause mortality within 30 days of surgery (0·30 versus 0·42 per cent; risk difference − 0·12 (−0·17 to −0·07) per cent).

Conclusion

Preoperative oral care by a dentist significantly reduced postoperative complications in patients who underwent cancer surgery.

Microscopic Investigation into the Electric Field Effect on Proximity-Induced Magnetism in Pt

Electric field effects on magnetism in metals have attracted widespread attention, but the microscopic mechanism is still controversial. We experimentally show the relevancy between the electric field effect on magnetism and on the electronic structure in Pt in a ferromagnetic state using element-specific measurements: x-ray magnetic circular dichroism (XMCD) and x-ray absorption spectroscopy (XAS). Electric fields are applied to the surface of ultrathin metallic Pt, in which a magnetic moment is induced by the ferromagnetic proximity effect resulting from a Co underlayer. XMCD and XAS measurements performed under the application of electric fields reveal that both the spin and orbital magnetic moments of Pt atoms are electrically modulated, which can be explained not only by the electric-field-induced shift of the Fermi level but also by the change in the orbital hybridizations.

Extensive first-principles molecular dynamics study on Li encapsulation into C60 and its experimental confirmation

The aim of increasing the production ratio of endohedral C₆₀ by impinging foreign atoms against C₆₀ is a crucial matter of the science and technology employed towards industrialization of these functional building block materials. Among these endohedral fullerenes, Li⁺@C₆₀ exhibits a wide variety of physical and chemical phenomena and has the potential to be applicable in areas spanning the medical field to photovoltaics. However, currently, Li⁺@C₆₀ can be experimentally produced with only ∼1% ratio using the plasma shower method with a 30 eV kinetic energy provided to the impinging Li⁺ ion. From extensive first-principles molecular dynamics simulations, it is found that the maximum production ratio of Li⁺@C₆₀ per hit is increased to about 5.1% (5.3%) when a Li⁺ ion impinges vertically on a six-membered ring of C₆₀ with 30 eV (40 eV) kinetic energy, although many C₆₀ molecules are damaged during this collision. On the contrary, when it impinges vertically on a six-membered ring with 10 eV kinetic energy, the production ratio remains at 1.3%, but the C₆₀ molecules are not damaged at all. On the other hand, when the C₆₀ is randomly oriented, the production ratio reduces to about 3.7 ± 0.5%, 3.3 ± 0.5%, and 0.2 ± 0.03% for 30 eV, 40 eV, and 10 eV kinetic energy, respectively. Based on these observations we demonstrate the possibility of increasing the production ratio by fixing six-membered rings atop C₆₀ using the Cu(111) substrate or UV light irradiation. In order to assess the ideal experimental production ratio, the ⁷Li solid NMR spectroscopy measurement is also performed for the multilayer randomly oriented C₆₀ sample irradiated by Li⁺ using the plasma shower method combined with inductively coupled plasma atomic emission spectroscopy (ICP-AES). Time-of-flight mass spectroscopy measurements are also performed to cross check whether Li⁺@C₆₀ molecules are produced in the sample. The resulting experimental estimate, 4% for 30 eV incident kinetic energy, fully agrees with our simulation results mentioned above, suggesting the consistency and accuracy of our simulations and experiments.

Clinical Results of Accelerated Hypofractionated Radiotherapy for Central-Type Small Lung Tumours

Purpose: We evaluated the efficacy and toxicity of accelerated hypofractionated radiotherapy (AHYPOF-RT) for central-type small lung tumours. Methods: Between November 2006 and January 2015, 40 patients with central-type small lung tumours underwent AHYPOF-RT delivered using 10 MV X-rays and a coplanar 3-field technique. The number of fractions ranged from 24 to 28, with a fraction size of 2.5–3 Gy. A total dose of 69–75 Gy to the isocentre of the planning target volume was administered to each patient. Cumulative survival and local control rates were calculated using the Kaplan–Meier method. Results: The 27 men and 13 women enrolled in the study had a median age of 79 years (range: 60−87 years). The tumour stage was T1a in 9 patients, T1b in 17 patients, and T2a in 14 patients, with a median size of 26.5 cm (range: 11–49 cm). The median follow-up period was 23 months. A complete response was achieved in 3 patients (7.5%), and a partial response, in 17 patients (42.5%). The overall 2-year and 3-year local control rates were 87.3% and 81.8% respectively; the 2-year and 3-year overall survival rates were 78.9% and 66.7% respectively. Grade 3 pneumonitis occurred in 3 patients; no other severe adverse events (≥grade 3) were observed in any patient. Conclusions: Accelerated hypofractionated radiotherapy using a fraction size of 2.5–3 Gy was highly safe and can be a more effective treatment option than conventional radiotherapy for patients with central-type small lung tumours.

Exploratory Analysis of Associations Between Postmarketing Safety Events and Approved Doses of New Drugs in Japan

While efficient and less onerous for the industry, the globalization of clinical drug development may lead to limited efforts to optimize drugs for regional conditions. We examined the association between clinical development pathways, approved doses, and postmarketing safety risks in Japan for 135 new molecular entities approved between 2004 and 2011. The risk of drug‐related deaths seemed higher when pharmaceutical companies chose exactly the same dose as in the United States, even after conducting Japanese dose‐ranging studies. We also found a positive association with drug‐related deaths when the review process was expedited and when Japanese dose‐ranging studies were not conducted for nonexpedited drugs. Our findings suggest that the decisions on regional dose settings and the choice of global clinical development pathways are associated in ways that may influence the postmarketing outcomes in the target populations.

Randomized clinical trial of 24 versus 72 h antimicrobial prophylaxis in patients undergoing open total gastrectomy for gastric cancer

BACKGROUND

Open total gastrectomy carries a high risk of surgical-site infection (SSI). This study evaluated the non-inferiority of antimicrobial prophylaxis for 24 compared with 72 h after open total gastrectomy.

METHODS

An open-label, randomized, non-inferiority study was conducted at 57 institutions in Japan. Eligible patients were those who underwent open total gastrectomy for gastric cancer. Patients were assigned randomly to continued use of β-lactamase inhibitor for either 24 or 72 h after surgery. The primary endpoint was the incidence of SSI, with non-inferiority based on a margin of 9 percentage points and a 90 per cent c.i. The secondary endpoint was the incidence of remote infection.

RESULTS

A total of 464 patients (24 h prophylaxis, 228; 72 h prophylaxis, 236) were analysed. SSI occurred in 20 patients (8·8 per cent) in the 24-h prophylaxis group and 26 (11·0 per cent) in the 72-h group (absolute difference -2·2 (90 per cent c.i. -6·8 to 2·4) per cent; P < 0·001 for non-inferiority). However, the incidence of remote infection was significantly higher in the 24-h prophylaxis group.

CONCLUSION

Antimicrobial prophylaxis for 24 h after total gastrectomy is not inferior to 72 h prophylaxis for prevention of SSI. Shortened antimicrobial prophylaxis might increase the incidence of remote infection. Registration number: UMIN000001062 ( http://www.umin.ac.jp).