Diagnostic Accuracy of Conjunctival Rt-Pcr in Sars-Cov-2: A Systematic Review and Diagnostic Accuracy Meta-Analysis

PURPOSE

To study the positivity rate of conjunctival realtime polymerase chain reaction (RT-PCR) testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

DESIGN

Systematic review and diagnostic accuracy meta-analysis.

METHODS

MEDLINE and EMBASE were queried using medical subject headings terms. Diagnostic accuracy meta-analyses and forest plots were obtained using the RevMan software.

RESULTS

After deduplication, appraisal of abstract titles and full-text analysis of 1441 articles, 42 articles with 3351 COVID-19 patients were included in this review. Of these, 412 conjunctival swabs/Schirmer paper strips tested positive for SARS-CoV-2 by RT-PCR. The pooled sensitivity of the RT-PCR tests across the 24 studies with laboratory-confirmed COVID-19 patients was 10.3%.

CONCLUSIONS

Only 1 in 10 RT-PCR tests performed on conjunctival swabs were positive for SARS-CoV-2. Although this suggests that SARS-CoV-2 is likely present and detectable in the conjunctiva, this detection method has low diagnostic potential.

Management of adult patients with podocytopathies: an update from the ERA Immunonephrology Working Group

The histopathological lesions, minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) are entities without immune complex deposits which can cause podocyte injury, thus are frequently grouped under the umbrella of podocytopathies. Whether MCD and FSGS may represent a spectrum of the same disease remains a matter of conjecture. Both frequently require repeated high-dose glucocorticoid therapy with alternative immunosuppressive treatments reserved for relapsing or resistant cases and response rates are variable. There is an unmet need to identify patients who should receive immunosuppressive therapies as opposed to those who would benefit from supportive strategies. Therapeutic trials focusing on MCD are scarce, and the evidence used for the 2021 Kidney Disease: Improving Global Outcomes (KDIGO) guideline for the management of glomerular diseases largely stems from observational and pediatric trials. In FSGS, the differentiation between primary forms and those with underlying genetic variants or secondary forms further complicates trial design. This article provides a perspective of the Immunonephrology Working Group (IWG) of the European Renal Association (ERA) and discusses the KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases focusing on the management of MCD and primary forms of FSGS in the context of recently published evidence, with a special emphasis on the role of rituximab, cyclophosphamide, supportive treatment options and ongoing clinical trials in the field.

The effect of a startle-based warning, age, sex, and secondary task on takeover actions in critical autonomous driving scenarios

Introduction: In highly autonomous driving scenarios, it is critical to identify strategies to accelerate reaction times since drivers may take too long to take over control of the vehicle. Previous studies reported that an Acoustic Startling Pre-Stimulus (ASPS, i.e., a loud warning preceding an action) accelerated reaction times in simple ankle flexion exercises.

Methods: In this study, we examined if an ASPS warning leads to shorter takeover reaction times in a sled-simulated evasive swerving maneuver. Twenty-eight participants (seven male adults, seven male teenagers, seven female adults, and seven female teenagers) were instructed to align a marker on the steering wheel with a marker on a lateral post as fast as they could as soon as the lateral sled perturbation (0.75 g) started. Four conditions were examined: with and without an ASPS (105 dB, played 250 ms before sled perturbation for 40 ms), and with and without a secondary task (i.e., texting). A catch trial (ASPS only) was used to minimize anticipation. Human kinematics were captured with an 8-camera 3D motion capture system.

Results: Results showed that the drivers’ hands lifted towards the steering wheel more quickly with the ASPS (169 ± 55 ms) than without (194 ± 46 ms; p = 0.01), and that adult drivers touched the steering wheel quicker with the ASPS (435 ± 54 ms) than without (470 ± 33 ms; p = 0.01). Similar findings were not observed for the teen drivers. Additionally, female drivers were found to lift their hands towards the steering wheel faster than male drivers (166 ± 58 ms vs. 199 ± 36 ms; p = 0.009).

Discussion: Our findings suggest that the ASPS may be beneficial to accelerate driver reaction times during the initiation of a correction maneuver, and that autonomous vehicle warnings may need to be tailored to the age and sex of the driver.

Repositioning forward-leaning vehicle occupants with a pre-pretensioner belt and a startle-based warning in pre-crash scenarios

OBJECTIVE

Pre-pretensioner (PPT) seatbelts have been found to be effective in controlling vehicle occupants' motion response to disturbances in optimally positioned occupants, but it is not clear how the PPT performs when the occupant is initially forward leaning. Previous work demonstrated that an acoustic startling pre-stimulus (ASPS) reduced trunk out-of-position in sled-simulated pre-crash maneuvers. Therefore, the aim of this study was to determine if coupling the PPT with the ASPS could reduce the needed magnitude and rate of belt tension of the PPT to reposition forward leaning occupants to their optimal position within the seatbelt.

METHODS

Sixteen belt-restrained adult human volunteers (8 males and 8 females) restrained by a 3-point seatbelt on a vehicle seat in a forward leaning posture on a sled simulating pre-crash braking (approx. 1 g of maximum acceleration and 0.3 s duration) were exposed to sled perturbations with three belt configurations (low and high force PPT and no PPT), and two warning conditions (ASPS and no-ASPS). Head and trunk positions were extracted from the 3D motion-capture data. Repeated measure ANOVAs were used to understand the effect of sex, PPT, ASPS, and repetition on head and trunk positions. A survival analysis was also performed to understand the probability of the occupants moving rearward in the different conditions.

RESULTS

The probability of the head and trunk to move rearward from the initial position was greater with the PPT than without the PPT (p = 0.01) and with the high force level than the low force level (p = 0.01). The interaction effect of ASPS x PPT showed that with no PPT, there was a greater probability for the head to move rearward from the initial position with ASPS than without ASPS (p < 0.03). The trunk shows a similar trend to the head, but the ASPS vs no-ASPS differences were not statistically significant (p = 0.06). No sex differences were found.

CONCLUSIONS

The PPT, particularly the high level, may be an effective countermeasure on its own to reduce trunk and head out-of-position in forward leaning postures in pre-crash scenarios. The ASPS reduced the occupants' head forward position when the PPT was not available.

COVID-19 in Patients with Glomerular Disease: Follow-Up Results from the IRoc-GN International Registry

Background

The acute and long-term effects of severe acute respiratory syndrome coronavirus 2 infection in individuals with GN are still unclear. To address this relevant issue, we created the International Registry of COVID-19 infection in GN.

Methods

We collected serial information on kidney-related and -unrelated outcomes from 125 GN patients (63 hospitalized and 62 outpatients) and 83 non-GN hospitalized patients with coronavirus disease 2019 (COVID-19) and a median follow-up period of 6.4 (interquartile range 2.3-9.6) months after diagnosis. We used logistic regression for the analyses of clinical outcomes and linear mixed models for the longitudinal analyses of eGFR. All multiple regression models were adjusted for age, sex, ethnicity, and renin-angiotensin-aldosterone system inhibitor use.

Results

After adjustment for pre-COVID-19 eGFR and other confounders, mortality and AKI did not differ between GN patients and controls (adjusted odds ratio for AKI=1.28; 95% confidence interval [CI], 0.46 to 3.60; P=0.64). The main predictor of AKI was pre-COVID-19 eGFR (adjusted odds ratio per 1 SD unit decrease in eGFR=3.04; 95% CI, 1.76 to 5.28; P<0.001). GN patients developing AKI were less likely to recover pre-COVID-19 eGFR compared with controls (adjusted 6-month post-COVID-19 eGFR=0.41; 95% CI, 0.25 to 0.56; times pre-COVID-19 eGFR). Shorter duration of GN diagnosis, higher pre-COVID-19 proteinuria, and diagnosis of focal segmental glomerulosclerosis or minimal change disease were associated with a lower post-COVID-19 eGFR.

Conclusions

Pre-COVID-19 eGFR is the main risk factor for AKI regardless of GN diagnosis. However, GN patients are at higher risk of impaired eGFR recovery after COVID-19-associated AKI. These patients (especially those with high baseline proteinuria or a diagnosis of focal segmental glomerulosclerosis or minimal change disease) should be closely monitored not only during the acute phases of COVID-19 but also after its resolution.

Combination treatment with rituximab, low-dose cyclophosphamide and plasma exchange for severe antineutrophil cytoplasmic antibody-associated vasculitis

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis can present with life-threatening lung-kidney syndromes. However, many controlled treatment trials excluded patients with diffuse alveolar hemorrhage or severely impaired glomerular filtration rates, and so the optimum treatment in these cases is unclear. In this retrospective cohort study, we report the outcomes of 64 patients with life-threatening disease treated with a combination regimen of rituximab, low-dose intravenous cyclophosphamide, oral glucocorticoids, and plasma exchange. At entry, the median estimated glomerular filtration rate was 9 mL/min, 47% of patients required dialysis, and 52% had diffuse alveolar hemorrhage. All patients received a minimum of seven plasma exchanges, and the median cumulative doses of rituximab, cyclophosphamide, and glucocorticoid were 2, 3, and 2.6 g, respectively, at six months. A total of 94% of patients had achieved disease remission (version 3 Birmingham Vasculitis Activity Score of 0) at this time point, and 67% of patients who required dialysis recovered independent kidney function. During long-term follow-up (median duration 46 months), overall patient survival was 85%, and 69% of patients remained free from end-stage kidney disease, which compares favorably to a historic cohort with severe disease treated with a conventional induction regimen. Combination treatment was associated with prolonged B cell depletion and low rates of relapse; 87% of patients were in continuous remission at month 36. The serious infection rate during total follow-up was 0.28 infections/patient/year, suggesting that combination treatment is not associated with an enduring risk of infection. Thus, we suggest that combination immunosuppressive therapy may permit glucocorticoid avoidance and provide rapid and prolonged disease control in patients with severe ANCA-associated vasculitis.

Quantitative characterization of AEB pulses across the modern fleet

OBJECTIVE

Characteristics of specific Automatic Emergency Braking (AEB) pulses can result in increased motion of the occupant, which can lead to the occupant being out-of-position such that when a crash occurs protection may be compromised. Quantifying these variations across the modern fleet is crucial to understand the loading environment to which vehicle occupants are exposed. Therefore, we categorized the AEB pulses based on acceleration pulse features such as deceleration magnitude, jerk, and ramp time.

METHODS

A total of 2278 AEB vehicle tests (years 2013-2019) were extracted from the Insurance Institute for Highway Safety (IIHS) database and analyzed. The following pulse characteristics were extracted: Jerk (g/s), Ramp-time (s), and Maximum deceleration (g). A subset of tests in which the tested vehicle did not contact the foam target (n = 1665) was analyzed further, with the following additional variables extracted: Deceleration time (s), Steady-state deceleration (g), and Duration (s). Other non-pulse related features were also considered: Test speed (20 and 40 km/h), Curb weight (Kg), and Vehicle Model Year. Using machine learning methods, the pulses were categorized into clusters. One-way ANOVAs for continuous variables and X² for categorical features were used to assess differences between clusters (p ≤ 0.05).

RESULTS

Using the entirety of the AEB vehicle tests extracted (n = 2278), a total of 3 clusters were selected. The three clusters showed significantly different Jerk, Ramp-time, and Maximum deceleration (p < 0.001). Target contact decreased in AEB tests with more recent vehicle model years (rate of contact 66% in 2014 vs 1.7% in 2019). In one cluster, Jerk and Maximum deceleration increased with vehicle model year. Using the subset of tests in which there was no contact with the foam target (n = 1665), 4 categories of pulses were selected. In both sets of clusters, Ramp-time and Jerk showed moderate inverse correlation (r = -0.7), while all other features showed a low correlation.

CONCLUSIONS

These results show that AEB technology improved over the years in obstacle avoidance. The identification of AEB pulse clusters is important in order to describe distinct approaches to achieving AEB and to be able to reproduce representative AEB pulses in the laboratory and understand the influences of those pulses on occupants' motion.

Longevity of SARS-CoV-2 immune responses in hemodialysis patients and protection against reinfection

Patients with end stage kidney disease receiving in-center hemodialysis (ICHD) have had high rates of SARS-CoV-2 infection. Following infection, patients receiving ICHD frequently develop circulating antibodies to SARS-CoV-2, even with asymptomatic infection. Here, we investigated the durability and functionality of the immune responses to SARS-CoV-2 infection in patients receiving ICHD. Three hundred and fifty-six such patients were longitudinally screened for SARS-CoV-2 antibodies and underwent routine PCR-testing for symptomatic and asymptomatic infection. Patients were regularly screened for nucleocapsid protein (anti-NP) and receptor binding domain (anti-RBD) antibodies, and those who became seronegative at six months were screened for SARS-CoV-2 specific T-cell responses. One hundred and twenty-nine (36.2%) patients had detectable antibody to anti-NP at time zero, of whom 127 also had detectable anti-RBD. Significantly, at six months, 71/111 (64.0%) and 99/116 (85.3%) remained anti-NP and anti-RBD seropositive, respectively. For patients who retained antibody, both anti-NP and anti-RBD levels were reduced significantly after six months. Eleven patients who were anti-NP seropositive at time zero, had no detectable antibody at six months; of whom eight were found to have SARS-CoV-2 antigen specific T cell responses. Independent of antibody status at six months, patients with baseline positive SARS-CoV-2 serology were significantly less likely to have PCR confirmed infection over the following six months. Thus, patients receiving ICHD mount durable immune responses six months post SARS-CoV-2 infection, with fewer than 3% of patients showing no evidence of humoral or cellular immunity.

Informing the Risk of Kidney Transplantation Versus Remaining on the Waitlist in the Coronavirus Disease 2019 Era

INTRODUCTION

There are limited data pertaining to comparative outcomes of remaining on dialysis versus kidney transplantation as the threat of coronavirus disease 2019 (COVID-19) remains. In this study we delineate the differential risks involved using serologic methods to help define exposure rates.

METHODS

From a cohort of 1433 patients with end-stage kidney disease (ESKD), we analyzed COVID-19 infection rates and outcomes in 299 waitlist patients compared with 237 transplant recipients within their first year post-transplant. Patients were followed over a 68-day period from the time our transplant program closed due to COVID-19.

RESULTS

The overall mortality rates in waitlist and transplant populations were equivalent (P = 0.69). However, COVID-19 infection was more commonly diagnosed in the waitlist patients (P = 0.001), who were more likely to be tested by reverse transcriptase polymerase chain reaction (P = 0.0004). Once infection was confirmed, mortality risk was higher in the transplant patients (P = 0.015). The seroprevalence in dialysis and transplant patients with undetected infection was 18.3% and 4.6%, respectively (P = 0.0001). After adjusting for potential screening bias, the relative risk of death after a diagnosis of COVID-19 remained higher in transplant recipients (hazard ratio = 3.36 [95% confidence interval = 1.19-9.50], P = 0.022).

CONCLUSIONS

Although COVID-19 infection was more common in the waitlist patients, a higher COVID-19‒associated mortality rate was seen in the transplant recipients, resulting in comparable overall mortality rates.

Results from the IRoc-GN international registry of patients with COVID-19 and glomerular disease suggest close monitoring

The effects of SARS-CoV-2 infection on individuals with immune-mediated glomerulonephritis, who are often undergoing immunosuppressive treatments, are unknown. Therefore, we created the International Registry of COVID infection in glomerulonephritis (IRoc-GN) and identified 40 patients with glomerulonephritis and COVID-19 followed in centers in North America and Europe. Detailed information on glomerulonephritis diagnosis, kidney parameters, and baseline immunosuppression prior to infection were recorded, as well as clinical presentation, laboratory values, treatment, complications, and outcomes of COVID-19. This cohort was compared to 80 COVID-positive control cases from the general population without glomerulonephritis matched for the time of infection. The majority (70%) of the patients with glomerulonephritis and all the controls were hospitalized. Patients with glomerulonephritis had significantly higher mortality (15% vs. 5%, respectively) and acute kidney injury (39% vs. 14%) than controls, while the need for kidney replacement therapy was not statistically different between the two groups. Receiving immunosuppression or renin-angiotensin-aldosterone system inhibitors at presentation did not increase the risk of death or acute kidney injury in the glomerulonephritis cohort. In the cohort with glomerulonephritis, lower serum albumin at presentation and shorter duration of glomerular disease were associated with greater risk of acute kidney injury and need for kidney replacement therapy. No differences in outcomes occurred between patients with primary glomerulonephritis versus glomerulonephritis associated with a systemic autoimmune disease (lupus or vasculitis). Thus, due to the higher mortality and risk of acute kidney injury than in the general population without glomerulonephritis, patients with glomerulonephritis and COVID-19 should be carefully monitored, especially when they present with low serum albumin levels.

Time saving, simple and reproducible method to quantify left ventricular function in patients with atrial fibrillation

Introduction

Echocardiography is essential for the management of patients with atrial fibrillation (AF), but current methods are time consuming and lack any evidence of reproducibility.

Purpose

To compare conventional averaging of consecutive beats with an index beat approach, where systolic and diastolic measurements are taken once after two prior beats with a similar RR interval (not more than 60 ms difference).

Methods

Transthoracic echocardiography was performed using a standardized and blinded protocol in patients enrolled into the RAte control Therapy Evaluation in permanent AF randomised controlled trial (RATE-AF; NCT02391337). AF was confirmed in all patients with a preceding 12-lead ECG. A minimum of 30-beat loops were recorded. Left ventricular function was determined using the recommended averaging of 5 and 10 beats and using the index beat method, with observers blinded to clinical details. Complete loops were used to calculate the within-beat coefficient of variation (CV) and intraclass correlation coefficient (ICC) for Simpson's biplane left ventricular ejection fraction (LVEF), global longitudinal strain (GLS) and filling pressure (E/e').

Results

160 patients (median age 75 years (IQR 69–82); 46% female) were included, with median heart rate 100 beats/min (IQR 86–112). For LVEF, the index beat had the lowest CV of 32% compared to 51% for 5 consecutive beats and 53% for 10 consecutive beats (p&lt;0.001). The index beat also had the lowest CV for GLS (26% versus 43% and 42%; p&lt;0.001) and E/e' (25% versus 41% and 41%; p&lt;0.001; see Figure for ICC comparison). Intra-operator reproducibility, assessed by the same operator from two different recordings in 50 patients, was superior for the index beat with GLS bias −0.5 and narrow limits of agreement (−3.6 to 2.6), compared to −1.0 for 10 consecutive beats (−4.0 to 2.0). For inter-operator variability, assessed in 18 random patients, the index beat also showed the smallest bias with narrow confidence intervals (CI). Using a single index beat did not impact on the validity of LVEF, GLS or E/e' measurement when correlated with natriuretic peptides. Index beat analysis substantially shortened analysis time; 35 seconds (95% CI 35 to 39 seconds) for measuring E/e' with the index beat versus 98 seconds (95% CI 92 to 104 seconds) for 10 consecutive beats (see Figure).

Conclusion

Index beat determination of left ventricular function improves reproducibility, saves time and does not compromise validity compared to conventional quantification in patients with heart failure and AF. After independent validation, the index beat method should be adopted into routine clinical practice.

Comparison for measurement of E/e'

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institute of Health Research UK

Neoantigen prediction and computational perspectives towards clinical benefit: recommendations from the ESMO Precision Medicine Working Group

BACKGROUND

The use of next-generation sequencing technologies has enabled the rapid identification of non-synonymous somatic mutations in cancer cells. Neoantigens are mutated peptides derived from somatic mutations not present in normal tissues that may result in the presentation of tumour-specific peptides capable of eliciting antitumour T-cell responses. Personalised neoantigen-based cancer vaccines and adoptive T-cell therapies have been shown to prime host immunity against tumour cells and are under clinical trial development. However, the optimisation and standardisation of neoantigen identification, as well as its delivery as immunotherapy are needed to increase tumour-specific T-cell responses and, thus, the clinical efficacy of current cancer immunotherapies.

METHODS

In this recommendation article, launched by the European Society for Medical Oncology (ESMO), we outline and discuss the available framework for neoantigen prediction and present a systematic review of the current scientific evidence.

RESULTS

A number of computational pipelines for neoantigen prediction are available. Most of them provide peptide major histocompatibility complex (MHC) binding affinity predictions, but more recent approaches incorporate additional features like variant allele fraction, gene expression, and clonality of mutations. Neoantigens can be predicted in all cancer types with high and low tumour mutation burden, in part by exploiting tumour-specific aberrations derived from mutational frameshifts, splice variants, gene fusions, endogenous retroelements and other tumour-specific processes that could yield more potently immunogenic tumour neoantigens. Ongoing clinical trials will highlight those cancer types and combinations of immune therapies that would derive the most benefit from neoantigen-based immunotherapies.

CONCLUSIONS

Improved identification, selection and prioritisation of tumour-specific neoantigens are needed to increase the scope of benefit from cancer vaccines and adoptive T-cell therapies. Novel pipelines are being developed to resolve the challenges posed by high-throughput sequencing and to predict immunogenic neoantigens.

High Prevalence of Asymptomatic COVID-19 Infection in Hemodialysis Patients Detected Using Serologic Screening

BACKGROUND

Strategies to minimize the risk of transmission and acquisition of COVID-19 infection in patients with ESKD receiving in-center hemodialysis have been rapidly implemented across the globe. Despite these interventions, confirmed COVID-19 infection rates have been high in the United Kingdom. Prevalence of asymptomatic disease in an adult hemodialysis population has not been reported. Also, to our knowledge, the development of humoral response to SARS-CoV-2 has not been previously reported in this population. Although serologic testing does not provide information on the infectivity of patients, seroprevalence studies may enable investigation of exposure within dialysis units and hence, assessment of current screening strategies.

METHODS

To investigate the seroprevalence of SARS-CoV-2 antibodies in a hemodialysis population, we used the Abbott IgG assay with the Architect system to test serum samples from 356 patients receiving in-center hemodialysis for SARS-CoV-2 antibodies.

RESULTS

Of 356 patients, 121 had been symptomatic when screened before a dialysis session and received an RT-PCR test; 79 (22.2% of the total study population) tested positive for COVID-19. Serologic testing of all 356 patients found 129 (36.2%) who tested positive for SARS-CoV-2 antibodies. Only two patients with PCR-confirmed infection did not seroconvert. Of the 129 patients with SARS-CoV-2 antibodies, 52 (40.3%) had asymptomatic disease or undetected disease by PCR testing alone.

CONCLUSIONS

We found a high seroprevalence of SARS-CoV-2 antibodies in patients receiving in-center hemodialysis. Serologic evidence of previous infection in asymptomatic or PCR-negative patients suggests that current diagnostic screening strategies may be limited in their ability to detect acute infection.

P0374TREATMENT EFFICACY OF BIOSIMILAR RITUXIMAB (TRUXIMA) COMPARED TO THE ORIGINATOR (MABTHERA) IN PATIENTS WITH ANCA ASSOCIATED VASCULITIS

Background and Aims

Truxima is a biosimilar version of rituximab. It was licensed & launched in the United Kingdom in April 2017. A biosimilar medicine is made to be highly similar in quality, safety and efficacy to existing licensed “reference” biological medicine and the cost is often significantly lower. A recent systematic review showed comparable long-term efficacy and safety of biosimilar rituximab to the originator drug in treatment of rheumatoid arthritis and non-hodgkin’s lymphoma. Fewer data are available in regards to the efficacy of biosimilar rituximab in treatment of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). A retrospective study was thus conducted in our centre to examine the efficacy of Truxima when compared to the reference rituximab (MabThera) in the treatment of patients with AAV.

Method

All patients with new or relapsing AAV who received first ever rituximab therapy between 1/1/2016 and 31/12/2018 were identified via hospital dispensing database. Patients were stratified into Truxima or MabThera treatment group depending on the version of rituximab administered. Primary outcomes that were assessed include: time to B cell depletion (defined as absolute B cell count (ABC) ≤10) and repletion (i.e ABC &gt;10 and &gt;20); time to antimyeloperoxidase(MPO)/antiproteinase 3(PR3)-ANCA negativity; Secondary outcomes assessed include: overall survival, time to major relapse (defined as relapse requiring further course of rituximab for remission induction); adverse events including episodes of neutropenia, hypogammaglobulinemia and major infusion reactions. Subgroup analysis in patients who received concomitant cyclophosphamide and rituximab or other induction therapy was performed to examine if it impacts on the treatment efficacy.

Results

59 and 60 patients received Truxima and MabThera respectively for treatment of new or relapsing AAV. The baseline characteristic (age, gender, entry estimated Glomerular Filtration Rate, proportion of patients received concomitant cyclophosphamide, ANCA serology and organ involvement) of both group were comparable. All patients achieved clinical remission following induction treatment. Using Kaplan Meier analysis and log rank test, no difference was identified in time to B cell depletion or repletion (Figure 1&2), MPO/PR3-ANCA negativity (Figure 3), overall survival or major relapses requiring further rituximab as induction therapy.

Treatment efficacy of Truxima and MabThera did not differ in subgroup analysis. However we observed that patients who received concurrent cyclophosphamide during induction therapy achieved MPO/PR3-ANCA negativity more rapidly compared to those who did not irrespective of the version of rituximab received. No difference in adverse events such as major infusion reactions was seen in either group upon first rituximab exposure. Two patients in each group developed reactions following repeated dosing of rituximab.

Conclusion

Biosimilar rituximab Truxima appears to have comparable treatment efficacy compared to the reference drug in our cohort of patients with AAV.

MO004THE SAFETY PROFILE OF REPEAT RITUXIMAB TREATMENT IN ANCA-ASSOCIATED VASCULITIS - A 10 YEAR SINGLE CENTRE STUDY

Background and Aims

Rituximab is a proven effective induction and remission-maintenance treatment in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Studies have identified hypogammaglobulinemia, infection, and late-onset neutropenia as potential adverse events. There is limited data on long-term outcomes following extended periods of B-cell depletion therapy with rituximab in AAV cohorts. We conducted a retrospective study to examine the safety profile of repeated rituximab treatment in AAV.

Method

All patients with AAV treated with rituximab between 1st January 2008 and 31st December 2018 were identified through local dispensary database. Patients were stratified into low (≤4g), medium (&gt;4g to ≤8g) and high (&gt;8g) dose groups according to the cumulative rituximab dose received until 1st October 2019. Baseline characteristics and events including death, opportunistic and severe infections (defined as infections required hospitalization and/or intravenous antibiotic administration), neutropenia (neutrophil count ≤1.5x109/L), hypogammaglobulinemia (IgG level≤5.0), infusion reactions and malignancy diagnosed post-rituximab treatment were examined and compared between the groups.

Results

364 patients (49% male, 52 year old mean age) received rituximab for treatment of active disease or remission maintenance. 49%(n=175) had repeat rituximab treatments (267/513 treatment courses for relapsing disease and 247/513 for remission maintenance). There were 262 (72%), 70(19%) and 32(9%) patients in low-, medium- and high-dose groups respectively. The median cumulative rituximab dose for each group was 2g, 6g and 12g (p&lt;0.001). Low-dose group patients were older (59 and 40 years, p&lt;0.001) and more likely to have renal-limited disease compared to high-dose groups (19%vs4%; p&lt;0.05). Conversely, there were more ear-nose-throat (ENT) /ocular limited (41% and 13%; p&lt;0.05) and antiproteinase 3 (PR3)-ANCA positive disease (56% vs 38%, p&lt;0.05) in high-dose compared to low-dose group. The overall median duration of follow up was 72 months (QR: 28-135months)(Table1).

Outcomes (Table2):

Infections: no difference in serious or opportunistic infection rate between groups (1.2 vs 0.1 vs 0.1infections/patient/year; p=0.18). 77% of opportunistic infections across all groups were related to herpesvirus (e.g. Cytomegalovirus/Herpes Zoster/Herpes Simplex) reactivation.

Hypogammaglobulinemia: incidence was comparable between groups (9.7% vs 10% vs 9%, p=0.91). Overall median time to event was 5 months from first rituximab.

Neutropenia: 101 patients had recorded neutropenia after rituximab (Low-dose: 32%; medium-dose 16% and High-dose: 22%, p&lt;0.05). All were related to concurrent immunosuppressants (e.g. Azathioprine, cyclophosphamide or mycophenolate) or infection. Events resolved after withdrawal or reduction of concurrent immunosuppressant or treatment of underlying infection.

Cancer: No difference in malignancy rate between groups (6% vs 14% vs 3%, p=0.22). 39 malignancies reported in 32 patients post rituximab treatment. The two commonest reported cancers were skin (36%) and breast cancer (21%)

Deaths: 58 patients died during the study period. Mortality rate in the low and medium-dose groups were comparable (82% survival at 30 month after last rituximab). Conversely, there were no deaths in the high-dose group.

Conclusion

In this large, single-centre cohort of patients with AAV, we did not observe an increased incidence of adverse events with increasing cumulative rituximab exposure. This likely reflects physician bias in patient selection for repeat treatment and suggests that in selected patients, extended periods of rituximab treatment might be safe. The superior survival seen in high-dose group was likely related to higher proportion of ENT/ocular limited vasculitis.

P0357VALIDATION OF THE ANCA RENAL RISK SCORE IN A LONDON COHORT: POTENTIAL IMPACT OF TREATMENT ON PREDICTION OUTCOME

Background and Aims

A renal risk score was recently developed to predict the risk of progression to end stage kidney disease (ESKD) in patients with ANCA-associated glomerulonephritis (ANCA-GN). The score defines three risk groups, each with distinct renal survival at 36 months: 68% of high-risk patients reaching ESKD, compared to 26% and 0% in the medium- and low-risk groups, respectively. The majority of patients (101/115) used to define the risk score were treated with IV cyclophosphamide and steroids. At our centre, we employ a combined low-dose IV cyclophosphamide, rituximab and oral corticosteroid induction regimen, with or without plasma exchange (PEX) depending on disease severity, for ANCA-GN. A recent cohort study suggested this combination regimen may lead to better renal survival. We thus hypothesized that choice of remission-induction treatment may affect prediction accuracy of the risk tool. We retrospectively test the validity of the ANCA renal risk score in patients with ANCA-GN treated at our centre.

Method

All patients with newly diagnosed, biopsy-proven ANCA-GN from 2006-19 were identified from local renal histopathology database. Patients with relapsing ANCA-GN, EGPA, other coexisting GN, or missing data on induction therapy or eventual renal outcome were excluded. ANCA-negative pauci-immune GN was included. Baseline demographics, ANCA serology, initial therapy and parameters in the ANCA risk score (including % normal glomeruli, % tubular atrophy and interstitial fibrosis (TAIF), and estimated glomerular filtration rate were collected. All patients were stratified using the risk tool and Kaplan Meier survival analysis was applied to examine the ESKD prediction. Subgroup analysis was then performed for patients who received the combination regimen of cyclophosphamide and rituximab.

Results

178 patients with a median follow up of 44 month were included in the analysis. The median age was 62 years and 82 patients (46%) were female. 94(53%) were MPO-ANCA positive, 66(37%) PR3-ANCA positive, 15 (8%) ANCA-negative, and 3 (2%) were double PR3/MPO-ANCA positive. 148 (83%) patients received the combination regimen, and 45 had concurrent PEX. Total of 37 (21%) patients reached ESKD. 29 (78%) of these, developed ESKD within 36 months of initial diagnosis. Using the risk score, 64(36%), 76(43%) and 38(21%) patients were deemed low-, medium- and high-risk, respectively. Very distinct poor renal survival at 36 months was seen in high-risk group (55% reaching ESKD, p&lt;0.01), but was less apparent between low- (95%) and medium-risk (90%)(p=0.052) (Figure1); In the subgroup of patients treated with combination regimen without concurrent PEX, the high-risk subgroup continues to demonstrate poor renal survival at 36 months (60% ESKD), but renal survival between low- and medium-risk group were comparable (0 and 2% respectively, p=0.57) (Figure 2).

Conclusion

In our cohort, the ANCA Renal Risk Score reliably predicted rapid ESKD progression at 36-month in high-risk patients, but was less accurate for distinguishing patients with low-and medium-risk. The subgroup analysis suggested combined cyclophosphamide and rituximab therapy may have modified long-term renal outcome especially in the medium-risk cohort, influencing the accuracy of the prediction tool. Large multi-centre cohorts are required to further evaluate the potential impact of treatment on predicting outcome.

Randomized, Controlled Trial of Tacrolimus and Prednisolone Monotherapy for Adults with De Novo Minimal Change Disease: A Multicenter, Randomized, Controlled Trial

BACKGROUND AND OBJECTIVES

Minimal change disease is an important cause of nephrotic syndrome in adults. Corticosteroids are first-line therapy for minimal change disease, but a prolonged course of treatment is often required and relapse rates are high. Patients with minimal change disease are therefore often exposed to high cumulative corticosteroid doses and are at risk of associated adverse effects. This study investigated whether tacrolimus monotherapy without corticosteroids would be effective for the treatment of de novo minimal change disease.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a multicenter, prospective, open-label, randomized, controlled trial involving six nephrology units across the United Kingdom. Adult patients with first presentation of minimal change disease and nephrotic syndrome were randomized to treatment with either oral tacrolimus at 0.05 mg/kg twice daily, or prednisolone at 1 mg/kg daily up to 60 mg daily. The primary outcome was complete remission of nephrotic syndrome after 8 weeks of therapy. Secondary outcomes included remission of nephrotic syndrome at 16 and 26 weeks, rates of relapse of nephrotic syndrome, and changes from baseline kidney function.

RESULTS

There were no significant differences between the tacrolimus and prednisolone treatment cohorts in the proportion of patients in complete remission at 8 weeks (21 out of 25 [84%] for prednisolone and 17 out of 25 [68%] for tacrolimus cohorts; P=0.32; difference in remission rates was 16%; 95% confidence interval [95% CI], -11% to 40%), 16 weeks (23 out of 25 [92%] for prednisolone and 19 out of 25 [76%] for tacrolimus cohorts; P=0.25; difference in remission rates was 16%; 95% CI, -8% to 38%), or 26 weeks (23 out of 25 [92%] for prednisolone and 22 out of 25 [88%] for tacrolimus cohorts; P=0.99; difference in remission rates was 4%; 95% CI, -17% to 25%). There was no significant difference in relapse rates (17 out of 23 [74%] for prednisolone and 16 out of 22 [73%] for tacrolimus cohorts) for patients in each group who achieved complete remission (P=0.99) or in the time from complete remission to relapse.

CONCLUSIONS

Tacrolimus monotherapy can be effective alternative treatment for patients wishing to avoid steroid therapy for minimal change disease.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2020_01_16_CJN06180519.mp3.

Substrate Supporting Disc Method for Confirmed Detection of Total Coliforms and E. coli in all Foods: Collaborative Study

The Coli Complete® substrate supporting disc (SSD) method for simultaneous confirmed total coliform count and Escherichia coli determination in all foods was compared with AOAC most probable number (MPN) methods, 966.23 and 966.24. Twenty-nine laboratories participated in this collaborative study in which 6 food types were analyzed. Four food types, raw ground beef, pork sausage, raw liquid milk, and nut meats, were naturally contaminated with coliform bacteria. Two foods, dry egg and fresh frozen vegetables, were seeded with coliforms. Three food types, ground beef, raw liquid milk, and pork sausage, were naturally contaminated with E. coli. Although pork sausage was naturally contaminated, the level was very low (&lt;10/50 g); therefore, additional E. coli were inoculated into 1 lot of this food type. Three food types, nut meats, dry egg, and fresh frozen vegetables, were inoculated with E. coli. For naturally contaminated samples, duplicate determinations were made on 3 separate lots for each food type. For inoculated samples, low, medium, and high contamination levels plus uninoculated control samples were examined in duplicate. Data were analyzed separately for total coliform bacteria and for E. coli. Mean log MPN counts were determined by the SSD method and the appropriate AOAC MPN method. Results were then analyzed for repeatability, reproducibility, and mean log MPN statistical equivalence. Results were statistically equivalent for all total coliform levels in all food types except frozen vegetable and raw nut meat uninoculated control samples and 1 lot of pork sausage where the SSD method produced statistically significant greater numbers. For the E. coli determinations, results were statistically equivalent across all samples and all levels for each food type. The SSD method has been adopted first action by AOAC International for confirmed detection of total coliforms and E. coli in all foods.

Long-term follow-up of a combined rituximab and cyclophosphamide regimen in renal anti-neutrophil cytoplasm antibody-associated vasculitis

Background

Current guidelines advise that rituximab or cyclophosphamide should be used for the treatment of organ-threatening disease in anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV), although few studies have examined the efficacy and safety of these agents in combination.

Methods

We conducted a single-centre cohort study of 66 patients treated with a combination of oral corticosteroids, rituximab and low-dose pulsed intravenous cyclophosphamide followed by a maintenance regimen of azathioprine and tapered steroid for the treatment of biopsy-proven renal involvement in AAV. Patients were followed for a median of 56 months. Case–control analysis with 198 propensity-matched cases from European Vasculitis Study Group (EUVAS) trials compared long-term differences in relapse-free, renal and patient survival.

Results

At entry, the median Birmingham Vasculitis Activity Score (BVAS) was 19 and estimated glomerular filtration rate was 25 mL/min. Cumulative doses of rituximab, cyclophosphamide and corticosteroids were 2, 3 and 4.2 g, respectively, at 6 months. A total of 94% of patients achieved disease remission by 6 months (BVAS < 0) and patient and renal survival were 84 and 95%, respectively, at 5 years. A total of 84% achieved ANCA-negative status and 57% remained B cell deplete at 2 years, which was associated with low rates of major relapse (15% at 5 years). The serious infection rate during long-term follow-up was 1.24 per 10 patient-years. Treatment with this regimen was associated with a reduced risk of death {hazard ratio [HR] 0.29 [95% confidence interval (CI) 0.125–0.675], P = 0.004}, progression to end-stage renal disease (ESRD) [HR 0.20 (95% CI 0.06–0.65), P = 0.007] and relapse [HR 0.49 (95% CI 0.25–0.97), P = 0.04] compared with propensity-matched patients enrolled in EUVAS trials.

Conclusions

This regimen is potentially superior to current standards of care, and controlled studies are warranted to establish the utility of combination drug approaches in the treatment of AAV.

A novel glucocorticoid-free maintenance regimen for anti-neutrophil cytoplasm antibody-associated vasculitis

Objectives

Glucocorticoids (GCs) are a mainstay of treatment for patients with ANCA-associated vasculitis (AAV) but are associated with significant adverse effects. Effective remission induction in severe AAV using extremely limited GC exposure has not been attempted. We tested an early rapid GC withdrawal induction regimen for patients with severe AAV.

Methods

Patients with active MPO- or PR3-ANCA vasculitis or ANCA-negative pauci-immune glomerulonephritis were included. Induction treatment consisted of two doses of rituximab, 3 months of low-dose CYC and a short course of oral GC (for between 1 and 2 weeks). Clinical, biochemical and immunological outcomes as well as adverse events were recorded.

Results

A total of 49 patients were included, with at least 12 months of follow-up in 46. All patients achieved remission, with decreases observed in creatinine, proteinuria, CRP, ANCA level and BVAS. Three patients requiring dialysis at presentation became dialysis independent. Two patients required the introduction of maintenance GC for treatment of vasculitis. Overall outcomes were comparable to those of two matched cohorts (n = 172) from previous European Vasculitis Society (EUVAS) trials, but with lower total exposure to CYC and GCs (P < 0.001) and reduced rates of severe infections (P = 0.02) compared with the RITUXVAS (rituximab versus cyclophosphamide in AAV) trial. We found no new cases of diabetes in the first year compared with historic rates of 8.2% from the EUVAS trials (P = 0.04).

Conclusion

Early GC withdrawal in severe AAV is as effective for remission induction as the standard of care and is associated with reduced GC-related adverse events.

Thermo-rheological responsive microcapsules for time-dependent controlled release of human mesenchymal stromal cells

Human mesenchymal stromal cells (hMSCs) are adult-source cells that have been extensively evaluated for cell-based therapies. hMSCs delivered by intravascular injection have been reported to accumulate at the sites of injury to promote tissue repair and can also be employed as vectors for the delivery of therapeutic genes. However, the full potential of hMSCs remains limited as the cells are lost after injection due to anoikis and the adverse pathologic environment. Encapsulation of cells has been proposed as a means of increasing cell viability. However, controlling the release of therapeutic cells over time to target tissue still remains a challenge today. Here, we report the design and development of thermo-rheological responsive hydrogels that allow for precise, time dependent controlled-release of hMSCs. The encapsulated hMSCs retained good viability from 76% to 87% dependent upon the hydrogel compositions. We demonstrated the design of different blended hydrogel composites with modulated strength (S parameter) and looseness of hydrogel networks (N parameter) to control the release of hMSCs from thermo-responsive hydrogel capsules. We further showed the feasibility for controlled-release of encapsulated hMSCs within 3D matrix scaffolds. We reported for the first time by a systematic analysis that there is a direct correlation between the thermo-rheological properties associated with the degradation of the hydrogel composite and the cell release kinetics. This work therefore provides new insights into the further development of smart carrier systems for stem cell therapy.

Genomic characterization of HER2-positive breast cancer and response to neoadjuvant trastuzumab and chemotherapy-results from the ACOSOG Z1041 (Alliance) trial

Background

HER2 (ERBB2) gene amplification and its corresponding overexpression are present in 15-30% of invasive breast cancers. While HER2-targeted agents are effective treatments, resistance remains a major cause of death. The American College of Surgeons Oncology Group Z1041 trial (NCT00513292) was designed to compare the pathologic complete response (pCR) rate of distinct regimens of neoadjuvant chemotherapy and trastuzumab, but ultimately identified no difference.

Patients and methods

In supplement to tissues from 37 Z1041 cases, 11 similarly treated cases were obtained from a single institution study (NCT00353483). We have extracted genomic DNA from both pre-treatment tumor biopsies and blood of these 48 cases, and performed whole genome (WGS) and exome sequencing. Coincident with these efforts, we have generated RNA-seq profiles from 42 of the tumor biopsies. Among patients in this cohort, 24 (50%) achieved a pCR.

Results

We have characterized the genomic landscape of HER2-positive breast cancer and investigated associations between genomic features and pCR. Cases assigned to the HER2-enriched subtype by RNA-seq analysis were more likely to achieve a pCR compared to the luminal, basal-like, or normal-like subtypes (19/27 versus 3/15; P = 0.0032). Mutational events led to the generation of putatively active neoantigens, but were overall not associated with pCR. ERBB2 and GRB7 were the genes most commonly observed in fusion events, and genomic copy number analysis of the ERBB2 locus indicated that cases with either no observable or low-level ERBB2 amplification were less likely to achieve a pCR (7/8 versus 17/40; P = 0.048). Moreover, among cases that achieved a pCR, tumors consistently expressed immune signatures that may contribute to therapeutic response.

Conclusion

The identification of these features suggests that it may be possible to predict, at the time of diagnosis, those HER2-positive breast cancer patients who will not respond to treatment with chemotherapy and trastuzumab.

ClinicalTrials.gov identifiers

NCT00513292, NCT00353483.

Abstract P2-02-14: Circulating tumor DNA predicts clinical outcome in early stage triple negative breast cancer

Background- Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer as these patients have the highest risk of recurrence and death. Only 35% of TNBC patients achieve a pathologic complete response (pCR) following neoadjuvant chemotherapy. Patients who do not achieve pCR have a 27% risk of distant recurrence and ultimate death at 3 years compared to 9% for pCR. Unidentified micrometastases are responsible for ultimate overt progression and death. Developing strategies to identify patients with minimal residual disease following curative treatment is an unmet need. Circulating tumor DNA (ctDNA) can characterize and monitor advanced cancers. In this study, we sought to assess if ctDNA can predict clinical outcome in TNBC.

Methods-Biospecimens were obtained from patients with stages II and III TNBC enrolled on a neoadjuvant trial (NCT02124902). Patients have a research biopsy and plasma for ctDNA collected at baseline, cycle 1 day 3, definitive surgery for those with residual disease, and at recurrence for those who relapse. Plasma for ctDNA is also collected every 6 months for 5 years after treatment. Patients receive docetaxel and carboplatin every 3 weeks X 6 cycles. Surgery is 3-5 weeks after chemotherapy. Six patients' serial tumor samples and germline DNA were studied by whole exome sequencing. The median sequencing depth was 90.13x. Sequencing was performed on samples with high cellularity (≥50%). All 6 patients also had serial ctDNA analyzed using Swift Biosciences Accel-Amplicon™ 56G Oncology Panel v2. After identifying somatic mutations in each breast tumor series, we determined the subset of mutations that intersected with the regions targeted by the Swift 56 gene panel. We then evaluated whether corresponding mutations could be detected in ctDNA, and if ctDNA predicted clinical outcome.

Results-Four of the 6 patients were non-pCR with residual disease following chemotherapy. We identified 627 somatic variants by exome analysis that were called by at least two somatic variant callers and passed additional quality filtering steps. Of these, 10 variants overlapped with the Swift panel. TP53 variants were identified in all 6 patients' tumor tissue samples. At least one TP53 variant was identified in 4 patients' baseline pre-chemotherapy ctDNA samples. Both pCR patients had either no detectable ctDNA TP53 mutations (NTN007-ref. in baseline tumor tissue was 19.58% variant allele frequency [VAF]); or clearance of ctDNA following chemotherapy from 4.45% VAF at baseline to 0.06% following chemotherapy (NTN004-ref. in baseline tumor tissue 37.34% VAF). Three non-PCR patients had persistent TP53 mutations in ctDNA during the treatment course. One non-pCR patient did not have detectable mutations in ctDNA. The only patient with recurrent disease whose ctDNA TP53 mutation persisted during the treatment course (baseline VAF-1.65%, cycle 1 day 3-0.78%, definitive surgery-0.09%), was found to have a higher ctDNA VAF at recurrence (29.55%).

Conclusion-In this pilot study, mutation tracking by ctDNA is sensitive and distinguishes pCR from non-pCR in TNBC patients receiving neoadjuvant chemotherapy. ctDNA also identifies recurrence following curative therapy. Evaluating ctDNA as a biomarker of outcome in TNBC is warranted.

Citation Format: Ademuyiwa F, Feng Y-Y, Skidmore Z, Kunisaki J, Walker J, Fulton R, Krysiak K, Skinner T, Weilbaecher K, Ma C, Griffith O, Griffith M. Circulating tumor DNA predicts clinical outcome in early stage triple negative breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-02-14.

Bioactive Hydrogel-Filament Scaffolds for Nerve Repair and Regeneration

The design of novel biomaterials is crucial for the advancement of tissue engineering in nerve regeneration. In this study we developed and evaluated novel biosynthetic scaffolds comprising collagen crosslinked with a terpolymer of poly(N-isopropylacrylamide) (PNiPAAm) as conduits for nerve growth. These collagen-terpolymer (collagen-TERP) scaffolds grafted with the laminin pentapeptide YIGSR were previously used as corneal substitutes in pigs and demonstrated enhanced nerve regeneration compared to allografts. The purpose of this project was to enhance neuronal growth on the collagen-TERP scaffolds through the incorporation of supporting fibers. Neuronal growth on these matrices was assessed in vitro using isolated dorsal root ganglia as a nerve source. Statistical significance was assessed using a one-way ANOVA. The incorporation of fibers into the collagen-TERP scaffolds produced a significant increase in neurite extension (p<0.05). The growth habit of the nerves varied with the type of fiber and included directional growth of the neurites along the surface of certain fiber types. Furthermore, the presence of fibers in the collagen-TERP scaffolds appeared to influence neurite morphology and function; neurites grown on fibers-incorporated collagen-TERP scaffolds expressed higher levels of Na channels compared to the scaffolds without fiber. Overall, our results suggest that incorporation of supporting fibers enhanced neurite outgrowth and that surface properties of the scaffold play an important role in promoting and guiding nerve regeneration. More importantly, this study demonstrates the potential value of tissue engineered collagen-TERP hybrid scaffolds as conduits in peripheral nerve repair.

Impending relapse of myelodysplastic syndrome after allogeneic transplant is difficult to diagnose and requires a multi-modal approach

Background

The only potentially curative therapy for myelodysplastic syndrome is allogeneic hematopoietic cell transplant; unfortunately, there is a high relapse rate. The objective of this study was to perform a detailed clinicopathologic study of patients with relapsed myeloid neoplasm following allogeneic hematopoietic cell transplant for myelodysplastic syndrome.

Methods

Pre-transplant, post-transplant, and relapse bone marrow and peripheral blood morphologic features (including dysplasia) were retrospectively evaluated by study authors. Clinical features and results of cytogenetic analysis and engraftment/chimerism studies were obtained from the medical record.

Results

Our study describes 21 patients with a median time to relapse of 6 months (range 2-82). Ten of the patients relapsed with higher grade disease, including six with overt acute myeloid leukemia. Pre-transplant megakaryocyte dysplasia was associated with dysplastic megakaryocytes in the relapse specimen; however, neither erythroid dysplasia nor granulocytic dysplasia were associated with their counterpart in the relapse specimen. Relapse specimens had a lower marrow cellularity and higher blast percentage than pre-transplant disease. Cytogenetic comparisons before and after transplant showed variety, including clonal evolution (22%), the same abnormal clone (33%), or a different abnormal clone (22%).

Conclusions

Our detailed review of post-transplant marrow biopsies prior to relapse highlights the difficulty in diagnosing relapse and particularly impending relapse.

The natural history of immunoglobulin M nephropathy in adults

Background

Immunoglobulin M (IgM) nephropathy is an idiopathic glomerulonephritis characterized by diffuse mesangial deposition of IgM. IgM nephropathy has been a controversial diagnosis since it was first reported, and there are few data identifying specific pathological features that predict the risk of progression of renal disease.

Methods

We identified 57 cases of IgM nephropathy among 3220 adults undergoing renal biopsy at our institution. Biopsies had to satisfy the following three criteria to meet the definition of IgM nephropathy in this study: (i) dominant mesangial staining for IgM, (ii) mesangial deposits on electron microscopy (EM) and (iii) exclusion of systemic disease.

Results

The median age was 42 years and 24 patients were male. Thirty-nine per cent of patients presented with the nephrotic syndrome, 49% presented with non-nephrotic proteinuria and 39% had eGFR <60 mL/min. The median post-biopsy follow-up was 40 months and serum creatinine had doubled in 31% by 5 years. Of histological parameters, glomerular sclerosis and tubular atrophy, but not mesangial proliferation, were risk factors for renal insufficiency. Thirty-nine per cent of nephrotic patients achieved complete remission, and outcome was significantly worse in those who did not respond to treatment. Focal segmental glomerulosclerosis was diagnosed in 80% of those undergoing repeat renal biopsy, despite ongoing mesangial IgM deposition.

Conclusions

We propose criteria for a consensus definition of IgM nephropathy.

Mycophenolate mofetil therapy in immunoglobulin A nephropathy: histological changes after treatment

Background

Endocapillary hypercellularity independently predicts renal outcome in immunoglobulin A nephropathy (IgAN). Mycophenolate mofetil (MMF) treatment is offered to patients presenting to the Imperial College Renal and Transplant Centre with IgAN and histological evidence of endocapillary hypercellularity. Clinical trials of MMF in IgAN have been inconclusive and have been limited by a lack of specific histological inclusion and exclusion criteria when recruiting patients. Evidence of histological improvement following MMF treatment would support its therapeutic use. We therefore reviewed histological changes after MMF therapy in a cohort of IgAN patients.

Method

Eighteen IgAN patients with native renal biopsies before and after repeated MMF treatment were identified. Patients were excluded if they had received any other immunosuppressive therapy, including corticosteroids. On the basis of the Oxford Classification of IgAN, we reviewed histological changes after MMF treatment.

Results

Nine patients (50%) were male. At diagnostic renal biopsy, the median age was 35 years [interquartile range (IQR) 30-41], serum creatinine was 97 µmol/L (IQR 79-153) and urine protein creatinine ratio (UPCR) was 146 mg/mmol (IQR 98-212). The median time between biopsies was 24 months (range 9-41). Following MMF treatment, repeat biopsy demonstrated statistically significant improvement in the mean percentage of glomeruli showing endocapillary hypercellularity and cellular/fibrocellular crescents. There was no change in mesangial hypercellularity, segmental sclerosis or tubular atrophy scores. Mesangial IgA deposition was also significantly reduced. Histopathological improvement persisted after the cessation of MMF therapy, suggesting that 2 years of treatment is adequate for benefit. The median serum creatinine remained stable at 3 years follow-up at 104 µmol/L (IQR 79-147).

Conclusion

MMF treatment is associated with histopathological improvement in IgAN.

Correction: Functionalised type-I collagen as a hydrogel building block for bio-orthogonal tissue engineering applications

Correction for 'Functionalised type-I collagen as a hydrogel building block for bio-orthogonal tissue engineering applications' by R. Ravichandran et al., J. Mater. Chem. B, 2016, 4, 318-326.

Studies on Oral Lichen Planus : I. Serum Immunoglobulins and Complement

In this preliminary study we explored the possibility of an immunologic component in oral lichen planus by assessment of serum immunoglobulins and complement levels, by skin tests for cellular immunity, and by fluorescent antibody techniques to detect immunoglobulins in the lesions. Although certain abnormalities were noted, none was consistent or of significant magnitude to clarify the cause of this disease.

Regenerative approaches for the cornea

The cornea is the transparent front part of the eye that transmits light to the back of the eye to generate vision. Loss of corneal transparency, if irreversible, leads to severe vision loss or blindness. For decades, corneal transplantation using human donor corneas has been the only option for treating corneal blindness. Despite recent improvement in surgical techniques, donor cornea transplantation remains plagued by risks of suboptimal optical results and visual acuity, immune rejection and eventually graft failure. Furthermore, the demand for suitable donor corneas is increasing faster than the number of donors, leaving thousands of curable patients untreated worldwide. Here, we critically review the state of the art of biomaterials for corneal regeneration. However, the lessons learned from the use of the cornea as a disease model will allow for extension of the biomaterials and techniques for regeneration of more complex organs such as the heart.

Ofatumumab for B cell depletion therapy in ANCA-associated vasculitis: a single-centre case series

Objectives. B cell depletion is an effective treatment strategy in ANCA-associated vasculitis (AAV). Ofatumumab is a fully humanized anti-CD20 mAb that has shown efficacy in the treatment of haematological malignancy and RA. The use of ofatumumab in the treatment of AAV has not previously been reported.

Methods. This study was based on a case series of eight patients who received ofatumumab, in conjunction with low-dose CYC and oral steroids, in the treatment of AAV.

Results. Eight patients received ofatumumab: seven for remission induction in active disease (three relapsing; four with new disease) and one for remission maintenance. B cell depletion was achieved in all patients by 1 month, and was sustained for at least 6 months. All patients with active disease achieved clinical remission (BVAS of zero, or BVAS ⩽5 if all scores due to persistent urinary abnormalities in the presence of stable or improving renal function) by 3 months. This was associated with a rapid fall in ANCA titres, reduced inflammatory responses and improvements in renal function. At 12 months, three patients had repopulated B cells associated with the recurrence of circulating ANCAs, although no patients experienced major clinical relapse in the first 24 months. No unexpected side effects were observed.

Conclusion. Treatment with ofatumumab resulted in similar serological and clinical responses to those seen in previous cohorts treated at our centre with a comparable CS, CYC and rituximab-based regimen. Ofatumumab should be considered an alternative B cell depleting agent in patients who are intolerant of, or unresponsive to, rituximab.

A genomic case study of mixed fibrolamellar hepatocellular carcinoma

We report the first comprehensive genomic analysis of a case of mixed conventional and fibrolamellar HCC (mFL-HCC). This study confirms the expression of DNAJB1:PRKACA, a fusion previously associated with pure FL-HCC but not conventional HCC, in mFL-HCC. These results indicate the DNAJB1:PRKACA fusion has diagnostic utility for both pure and mixed FL-HCC.

Background

Mixed fibrolamellar hepatocellular carcinoma (mFL-HCC) is a rare liver tumor defined by the presence of both pure FL-HCC and conventional HCC components, represents up to 25% of cases of FL-HCC, and has been associated with worse prognosis. Recent genomic characterization of pure FL-HCC identified a highly recurrent transcript fusion (DNAJB1:PRKACA) not found in conventional HCC.

Patients and Methods

We performed exome and transcriptome sequencing of a case of mFL-HCC. A novel BAC-capture approach was developed to identify a 400 kb deletion as the underlying genomic mechanism for a DNAJB1:PRKACA fusion in this case. A sensitive Nanostring Elements assay was used to screen for this transcript fusion in a second case of mFL-HCC, 112 additional HCC samples and 44 adjacent non-tumor liver samples.

Results

We report the first comprehensive genomic analysis of a case of mFL-HCC. No common HCC-associated mutations were identified. The very low mutation rate of this case, large number of mostly single-copy, long-range copy number variants, and high expression of ERBB2 were more consistent with previous reports of pure FL-HCC than conventional HCC. In particular, the DNAJB1:PRKACA fusion transcript specifically associated with pure FL-HCC was detected at very high expression levels. Subsequent analysis revealed the presence of this fusion in all primary and metastatic samples, including those with mixed or conventional HCC pathology. A second case of mFL-HCC confirmed our finding that the fusion was detectable in conventional components. An expanded screen identified a third case of fusion-positive HCC, which upon review, also had both conventional and fibrolamellar features. This screen confirmed the absence of the fusion in all conventional HCC and adjacent non-tumor liver samples.

Conclusion

These results indicate that mFL-HCC is similar to pure FL-HCC at the genomic level and the DNAJB1:PRKACA fusion can be used as a diagnostic tool for both pure and mFL-HCC.

Coloured cornea replacements with anti-infective properties: expanding the safe use of silver nanoparticles in regenerative medicine

Despite the broad anti-microbial and anti-inflammatory properties of silver nanoparticles (AgNPs), their use in bioengineered corneal replacements or bandage contact lenses has been hindered due to their intense yellow coloration. In this communication, we report the development of a new strategy to pre-stabilize and incorporate AgNPs with different colours into collagen matrices for fabrication of corneal implants and lenses, and assessed their in vitro and in vivo activity.