Role of the Thalamus in Basal Forebrain Regulation of Neural Activity in the Primary Auditory Cortex

Many studies have implicated the basal forebrain (BF) as a potent regulator of sensory encoding even at the earliest stages of or cortical processing. The source of this regulation involves the well-documented corticopetal cholinergic projections from BF to primary cortical areas. However, the BF also projects to subcortical structures, including the thalamic reticular nucleus (TRN), which has abundant reciprocal connections with sensory thalamus. Here we present naturalistic auditory stimuli to the anesthetized rat while making simultaneous single-unit recordings from the ventral medial geniculate nucleus (MGN) and primary auditory cortex (A1) during electrical stimulation of the BF. Like primary visual cortex, we find that BF stimulation increases the trial-to-trial reliability of A1 neurons, and we relate these results to change in the response properties of MGN neurons. We discuss several lines of evidence that implicate the BF to thalamus pathway in the manifestation of BF-induced changes to cortical sensory processing and support our conclusions with supplementary TRN recordings, as well as studies in awake animals showing a strong relationship between endogenous BF activity and A1 reliability. Our findings suggest that the BF subcortical projections that modulate MGN play an important role in auditory processing.

FRI0170 THERAPEUTIC ΤARGETS AND QUALITY INDICATORS IN SYSTEMIC LUPUS ERYTHEMATOSUS (SLE), DEFINED ACCORDING TO THE 2019 UPDATE OF THE EULAR RECOMMENDATIONS: DATA FROM THE “ATTIKON“ LUPUS COHORT

Background:

Targets of therapy and quality of care are receiving increased attention in the management of SLE, as outlined in the 2019 update of the EULAR recommendations for SLE treatment.

Objectives:

To assess compliance with quality indicators and attainment of treatment targets, according to recent EULAR recommendations, in the SLE cohort of “Attikon” Rheumatology Unit.

Methods:

100 consecutive SLE patients followed for at least one year were. A 30 item Quality Indicator Set (QIS) was developed, according to the 2019 EULAR recommendations for SLE, to include laboratory tests for diagnosis and monitoring, evaluation of disease activity and damage using validated indices, use of patient-reported outcomes, counselling for women’s health and reproduction issues, attainment of targets of therapy [remission or low disease activity state (LLDAS) with low-dose glucocorticoids (GC, ≤7.5mg/day prednizone) and hydroxychloroquine (HCQ dose≤5mg/kg/day)], prevention of disease flares and prevention and management of co-morbidities. Chart review and patient interview was performed to assess the degree of compliance with each item of the QIS and achievement of treatment targets.

Results:

Disease activity was monitored by means of validated indices in 31% and antiphospholipid antibody testing during the first 6 months from diagnosis was performed in 58.8% of patients. Sustained remission (defined as remission of a sustained period of 12 months) or LLDAS was achieved by only 3% and 22% respectively; in contrast, other targets of therapy, such as ≤1 minor flares during last year, were achieved by 85% (43% had complete absence of flares), with 90.2% of patients receiving low-dose GC and 81.8% corrected HCQ dose. Fertility and pregnancy counselling were offered in 40% (12/30 eligible women) and 63.3% (19/30) of patients, respectively, while 65.4% had a Pap Test and only 3 of 32 eligible patients had received the HPV vaccine. Annual lipid status was assessed in 43% and counselling for smoking cessation in 44.6%. Flu vaccination was performed in 77%, while pneumococcal (including both of the pneumococcal vaccines) and herpes-zoster vaccination, were given in 32.7% and 2% (1/44 eligible patients) respectively.

Conclusion:

Our real-life data suggest low vaccination rates (excluding flu) and suboptimal management of cardiovascular risk factors in lupus patients. While the majority of patients received the suggested doses of GC and HCQ, only one quarter of patients achieved remission or LLDAS. There is an unmet need for new therapies in SLE to improve therapy targets.

References:

[1]Arora S, Sequeira W, Yazdany J, Jolly M, “Does Systemic Lupus Erythematosus Care Provided in a Lupus Clinic Result in Higher Quality of Care Than That Provided in a General Rheumatology Clinic?”, Arthritis Care Res. 2018 Dec;70(12):1771-1777. doi: 10.1002/acr.23569. Epub 2018 Nov 10.

Disclosure of Interests:

KATERINA HAVATZA: None declared, KONSTANTINA TOGIA: None declared, Sofia Flouda: None declared, Antigoni Pieta: None declared, Ourania Gioti: None declared, Dionysis Nikolopoulos: None declared, Noemin Kapsala: None declared, Aliki Ntourou: None declared, Panagiota Rapsomaniki: None declared, Thaleia Gerogianni: None declared, Dimitrios Tseronis: None declared, Michail Aggelakos: None declared, Theofanis Karageorgas: None declared, PELAGIA KATSIMPRI: None declared, George Bertsias Grant/research support from: GSK, Consultant of: Novartis, Konstantinos Thomas: None declared, DIMITRIOS BOUMPAS Grant/research support from: Unrestricted grant support from various pharmaceutical companies, Antonis Fanouriakis Paid instructor for: Paid instructor for Enorasis, Amgen, Speakers bureau: Paid speaker for Roche, Genesis Pharma, Mylan

AB1201 INCREASING RATES OF INFLUENZA VACCINATION COVERAGE IN RHEUMATOID ARTHRITIS PATIENTS: DATA FROM A MULTICENTER, LONGITUDINAL COHORT STUDY OF 1,406 PATIENTS

Background:

Despite the increased incidence of influenza infection in rheumatoid arthritis (RA) patients, vaccination coverage has been shown to be suboptimal. Prospective data regarding the current rate and predictors of influenza vaccination adherence in RA patients are limited.

Objectives:

To calculate the current rate and predictors of influenza vaccination in a real-life, prospective, longitudinal RA cohort.

Methods:

Data regarding demographics, disease characteristics, treatments and co-morbidities from a multi-center, longitudinal cohort of Greek RA patients were collected at baseline and ~ 3 years later. Disease and patient characteristics were compared between patients with at least one influenza vaccine administration and non-vaccinated ones, during the 3 year follow-up period.

Results:

From a cohort of 1,569 RA patients, 1,406 with available vaccination data at baseline and 3 years later (mean interval: 2.9 years) were included; (women: 80.4%, mean age: 61.8 years, mean disease duration: 9.7 years, RF and/or anti-CCP positive: 50.4%, mean DAS-28 = 3.33, mean HAQ: 0.44, bDMARD use: 44.8%). At baseline, 54.2% of patients reported influenza vaccination in the past (31.8% during the previous season), while during the 3 year follow-up period, 81% had ≥1 influenza vaccinations (p=<0.001). Patients who received ≥1 influenza vaccine were older (63.5 vs. 54.7 years, p<0.001), were more likely to be seropositive (59.2% vs. 45.2%, p<0.001), had higher HAQ (0.46 vs. 0.36, p=0.02) and BMI (27.7 vs. 26.9, p=0.02) at baseline, more likely to be treated with bDMARDs (46.8% vs. 36.4%, p<0.001) and more likely to have chronic lung disease (9.7% vs. 5.3%, p=0.02), dyslipidemia (36.4% vs. 24.2%, p<0.001), hypertension (46.1% vs. 29.2%, p<0.001) and to report vaccination against influenza the previous season before baseline evaluation (34.9% vs. 18.2%, p<0.001). By multivariate analysis, history of influenza vaccination during the last season before baseline (OR=1.87, CI: 1.27-2.74, p=0.001), bDMARD treatment (OR=1.51, CI: 1.07-2.13, p=0.018) and age (OR=1.05, CI: 1.04-1.06, p<0.001) were independent predictors of influenza vaccination.

Conclusion:

In this ongoing, longitudinal, prospective, real-life RA cohort study, a significant increase in the influenza vaccination coverage was noted (from 53% to 81%). Influenza vaccination was independently associated with recent history of influenza vaccination, older age, and bDMARD treatment.

Acknowledgments:

Supported by grants from the Greek Rheumatology Society and Professional Association of Rheumatologists.

Disclosure of Interests:

Konstantinos Thomas: None declared, Argyro Lazarini: None declared, Evripidis Kaltsonoudis: None declared, Alexandros Drosos: None declared, ARGYRO REPA: None declared, Prodromos Sidiropoulos: None declared, Kalliopi Fragkiadaki: None declared, Maria Tektonidou Grant/research support from: AbbVie, MSD, Novartis and Pfizer, Consultant of: AbbVie, MSD, Novartis and Pfizer, Petros Sfikakis Grant/research support from: Grant/research support from Abvie, Novartis, MSD, Actelion, Amgen, Pfizer, Janssen Pharmaceutical, UCB, Panagiota Tsatsani: None declared, Sousana Gazi: None declared, Pelagia Katsimbri: None declared, Dimitrios Boumpas: None declared, Evangelia Argyriou: None declared, Kyriaki Boki: None declared, Gerasimos Evangelatos: None declared, Alexios Iliopoulos: None declared, Konstantina Karagianni: None declared, Lazaros Sakkas: None declared, Konstantinos Melissaropoulos: None declared, Panagiotis Georgiou: None declared, Eleftheria Grika: None declared, PANAYIOTIS VLACHOYIANNOPOULOS: None declared, Theodoros Dimitroulas: None declared, Alexandros Garyfallos Grant/research support from: MSD, Aenorasis SA, Speakers bureau: MSD, Novartis, gsk, Constantinos Georganas: None declared, Periklis Vounotrypidis: None declared, Konstantinos Ntelis: None declared, Maria Areti: None declared, George D Kitas: None declared, Dimitrios Vassilopoulos: None declared

OP0103 DOES GENDER, AGE OR SUBPOPULATION INFLUENCE THE MAINTENANCE OF CLINICAL REMISSION IN AXIAL SPONDYLOARTHRITIS FOLLOWING CERTOLIZUMAB PEGOL DOSE REDUCTION?

Background:

Previous studies have shown that withdrawing tumour necrosis factor inhibitors (TNFi) in patients (pts) with axial spondyloarthritis (axSpA) who have achieved sustained remission often leads to relapse.1However, none have formally tested TNFi dose reduction strategies in a broad axSpA population or evaluated whether relapse following TNFi dose reduction and withdrawal is associated with a specific demographic subgroup.

Objectives:

C-OPTIMISE evaluated the percentage of pts without flare after TNFi dose continuation, reduction or withdrawal in adults with early axSpA treated with the Fc-free, PEGylated TNFi certolizumab pegol (CZP). Here, we analyse whether responses to reduced maintenance dose were comparable in pts stratified by axSpA subpopulation, gender and age.

Methods:

C-OPTIMISE (NCT02505542) was a multicentre, two-part phase 3b study in adults with early (<5 years’ symptom duration) active axSpA (stratified for radiographic [r]- and non-radiographic [nr]- axSpA). Pts received CZP 200 mg every 2 weeks (wks) (Q2W; 400 mg loading dose at Wks 0, 2 and 4) during the open-label induction period. At Wk 48, pts in sustained remission (Ankylosing Spondylitis Disease Activity Score [ASDAS] <1.3 at Wk 32 or 36 [if ASDAS <1.3 at Wk 32, it must be <2.1 at Wk 36, or vice versa] and at Wk 48) were randomised to double-blind full maintenance dose (CZP 200 mg Q2W); reduced maintenance dose (CZP 200 mg every 4 wks [Q4W]) or placebo (PBO) for a further 48 wks (maintenance period). The primary endpoint was the percentage of pts not experiencing a flare (ASDAS ≥2.1 at two consecutive visits or ASDAS >3.5 at any timepoint) during Wks 48–96. Analyses were conducted on subgroups according to axSpA subpopulation, gender and age ≤/> the median age of the randomised set (32 years).

Results:

During the 48-wk induction period, 43.9% of patients (323/736) achieved sustained remission and 313 pts entered the 48-wk maintenance period (r/nr-axSpA: 168/145 pts; males/females: 247/66 pts; age ≤32/>32: 165/148 pts). During the maintenance period, responses in r- and nr-axSpA pts were comparable across all three randomised arms. 83.9% r-axSpA and 83.3% nr-axSpA pts receiving the full CZP maintenance dose did not experience a flare, and in the reduced maintenance dose arm 82.1% r-axSpA and 75.5% nr-axSpA pts did not experience a flare. In the PBO group this was reduced to 17.9% and 22.9%, respectively. Similar responses were seen in pts stratified by gender or age, with substantially higher percentages of pts randomised to CZP full or reduced maintenance dose remaining free of flares compared to PBO in all subgroups (Figure).

Conclusion:

The results of C-OPTIMISE indicate that a reduced maintenance dose is suitable for pts with axSpA who achieve sustained remission following 1 year of CZP treatment, regardless of axSpA subpopulation, gender or age. Complete treatment withdrawal is not recommended due to the high risk of flare.

References:

[1]Landewe R. Lancet 2018;392:134–44.

Acknowledgments:

This study was funded by UCB Pharma. Editorial services were provided by Costello Medical

Disclosure of Interests:

Robert B.M. Landewé Consultant of: AbbVie; AstraZeneca; Bristol-Myers Squibb; Eli Lilly & Co.; Galapagos NV; Novartis; Pfizer; UCB Pharma, Désirée van der Heijde Consultant of: AbbVie, Amgen, Astellas, AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Cyxone, Daiichi, Eisai, Eli-Lilly, Galapagos, Gilead Sciences, Inc., Glaxo-Smith-Kline, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi, Takeda, UCB Pharma; Director of Imaging Rheumatology BV, Maxime Dougados Grant/research support from: AbbVie, Eli Lilly, Merck, Novartis, Pfizer and UCB Pharma, Consultant of: AbbVie, Eli Lilly, Merck, Novartis, Pfizer and UCB Pharma, Speakers bureau: AbbVie, Eli Lilly, Merck, Novartis, Pfizer and UCB Pharma, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Filip van den Bosch Consultant of: AbbVie, Celgene Corporation, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, and UCB, Speakers bureau: AbbVie, Celgene Corporation, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, and UCB, Karl Gaffney Grant/research support from: AbbVie, Celgene, MSD, Novartis, Pfizer, and UCB Pharma, Consultant of: AbbVie, Celgene, MSD, Novartis, Pfizer, and UCB Pharma, Speakers bureau: AbbVie, Celgene, MSD, Novartis, Pfizer, and UCB Pharma, Lars Bauer Employee of: UCB Pharma, Bengt Hoepken Employee of: UCB Pharma, Natasha de Peyrecave Employee of: UCB Pharma, Karen Thomas Employee of: UCB Pharma, Lianne S. Gensler Grant/research support from: Pfizer, Novartis, UCB, Consultant of: AbbVie, Eli Lilly, GSK, Novartis, UCB

FRI0147 PREVALENCE OF COMORBIDITIES IN ANTIPHOSPHOLIPID SYNDROME VERSUS RHEUMATOID ARTHRITIS: A MULTICENTRE, AGE- AND SEX-MATCHED STUDY

Background:

Comorbidities in rheumatic diseases (RDs) have been associated with increased morbidity and mortality. Evidence on prevalence of comorbidities in antiphospholipid syndrome (APS) and its difference from high comorbidity burden RDs is limited.

Objectives:

To compare the prevalence of common comorbidities between APS [primary (PAPS) and Systemic lupus erythematosus (SLE)-APS] and Rheumatoid arthritis (RA) patients.

Methods:

326 APS patients from the Greek registry (237 women, mean age 48.7±13.4 years, 161 PAPS) were matched 1:2 for age and sex with 652 RA patients from Greek RA Registry. Prevalence of cardiovascular (CV) risk factors, stroke, coronary artery disease (CAD), osteoporosis, diabetes mellitus (DM), Chronic obstructive pulmonary disease (COPD), depression and neoplasms were compared between APS and RA using logistic regression analysis.

Results:

Regarding CV burden, hyperlipidemia and obesity (ΒMI≥30) were comparable while hypertension, smoking, CAD and stroke were more prevalent in APS compared to RA patients (Table 1). Osteoporosis and depression were more frequent in APS while DM, COPD and neoplasms were comparable between two groups. Comparison of APS subgroups to 1:2 matched RA patients revealed that smoking and stroke were more prevalent in PAPS and SLE-APS vs RA. Hypertension, CAD and osteoporosis were more prevalent only in SLE-APS vs. RA while DM was less prevalent in PAPS vs. RA patients.

Table 1.

Comparison of comorbidities between Antiphospholipid syndrome (APS) vs. matched Rheumatoid Arthritis (RA) patients and between primary APS (PAPS) or Systemic Lupus Erythematosus-APS (SLE-APS) vs matched RA patients

APSRAOR*PAPSRAORSLE-APSRAORn (%)326652161322165330Hypertension97 (29.8)136 (21)1.61 (1.19-2.18)40 (25)75 (23.3)1.09 (0.70-1.69)57 (34.6)61 (18.5)2.33 (1.52-3.56)Smoking175 (53.7)264 (40.5)1.70 (1.30-2.22)87 (54)142 (44)1.49 (1.02-2.18)88 (53.3)122 (37)1.95 (1.33-2.85)Hyperlipidemia79 (24.2)135 (20.7)1.23 (0.89-1.68)40 (24.8)62 (19.3)1.39 (0.88-2.18)39 (23.6)73 (22)1.09 (0.70-1.70)Obesity48 (20.5)105 (19.5)1.06 (0.73-1.56)20 (17)51 (19)0.86 (0.49-1.52)28 (24)54 (19.7)1.28 (0.76-2.15)Stroke±66 (20.3)9 (1.4)13.8 (6.5-29.1)36 (22.4)4 (1.2)19.9 (6.6-59.9)30 (18.2)5 (1.5)7.8 (2.7-22.6)Coronary disease±16 (4.9)13 (2)3.14 (1.17-8.45)2 (1.2)7 (2.2)0.46 (0.04-4.77)14 (8.5)6 (1.8)10.9 (2.7-44.3)Osteoporosis×66 (20.3)92 (14)1.45 (1.01-2.06)19 (11.8)42 (13)0.96 (0.54-1.73)47 (28.5)50 (15)1.91 (1.20-3.05)Diabetes×18 (5.5)58 (9)0.58 (0.33-1.01)5 (3)29 (9)0.34 (0.13-0.89)13 (8)29 (9)0.88 (0.44-1.79)COPD≠11 (3.4)14 (2.2)1.26 (0.56-2.84)3 (1.9)6 (2)0.96 (0.23-4.0)8 (5)8 (2.4)1.28 (0.44-3.72)Depression#53 (16.3)66 (10)1.70 (1.15-2.53)23 (14)30 (9.3)1.69 (0.93-3.05)30 (18.2)36 (10.9)1.65 (0.96-2.84)Neoplasms˅14 (4.3)27 (4.1)1.05 (0.54-2.06)5 (3)12 (3.7)0.84 (0.28-2.52)9 (5.5)15 (4.6)1.31 (0.55-3.1)

*OR: Odds ratio, crude or adjusted for:

 ± age, sex, smoking, hypertension, hyperlipidemia, BMI, corticosteroid (Cs) duration

 × Cs duration

 ≠ smoking, Cs duration

 #sex, disease duration, Cs duration

 ˅ age, disease duration

Conclusion:

Comorbidity burden in APS (PAPS and SLE-APS) is comparable or even higher to that in RA, entailing a high level of diligence for CV risk prevention, awareness for depression and corticosteroid exposure minimization.

Disclosure of Interests:

Stylianos Panopoulos: None declared, Konstantinos Thomas: None declared, Georgios Georgiopoulos: None declared, Dimitrios Boumpas Grant/research support from: Unrestricted grant support from various pharmaceutical companies, Christina Katsiari: None declared, George Bertsias Grant/research support from: GSK, Consultant of: Novartis, Alexandros Drosos: None declared, Kyriaki Boki: None declared, Theodoros Dimitroulas: None declared, Alexandros Garyfallos Grant/research support from: MSD, Aenorasis SA, Speakers bureau: MSD, Novartis, gsk, Charalambos Papagoras: None declared, PELAGIA KATSIMPRI: None declared, Apostolos Tziortziotis: None declared, Christina Adamichou: None declared, Evripidis Kaltsonoudis: None declared, Evangelia Argyriou: None declared, GEORGIOS VOSVOTEKAS Grant/research support from: MSD, Janssen, Consultant of: MSD, Novartis, Roche, UCB pharma, Bristol-Myers Squibb, AbbVie, Speakers bureau: UCB pharma, Menarini, Bristol-Myers Squibb, MSD, Petros Sfikakis Grant/research support from: Grant/research support from Abvie, Novartis, MSD, Actelion, Amgen, Pfizer, Janssen Pharmaceutical, UCB, Dimitrios Vassilopoulos: None declared, Maria Tektonidou Grant/research support from: AbbVie, MSD, Novartis and Pfizer, Consultant of: AbbVie, MSD, Novartis and Pfizer

AB1216 INTERSTITIAL PNEUMONIA WITH AUTOIMMUNE FEATURES (IPAF): A SINGLE CENTER, PROSPECTIVE STUDY

Background:

Interstitial pneumonia with autoimmune features (IPAF)1describes a group of patients with interstitial lung disease and autoimmune features who do not meet the classification criteria for a specific connective tissue disease. Limited data regarding IPAF are available so far.

Objectives:

To identify the epidemiological and clinical characteristics of patients with IPAF and to observe disease progression, response to treatment and frequency of infections in 1-year follow-up period.

Methods:

Thirty-nine patients from ‘Attikon’ University Hospital of Athens fulfilling the IPAF criteria were enrolled. Clinical and laboratory findings, comorbidities, medications, pulmonary outcomes assessed with repeated pulmonary function tests (PFTs) and chest HRCT and complications in a 1-year follow-up period were documented for each patient. Univariate models were performed in order to identify determinants of infection and clinically significant difference in PFTs (defined as change of ≥ 10% in FVC and/or ≥ 15% in DLCO).

Results:

The mean age at the time of IPAF diagnosis was 63.2 (±11) years and 62% of the patients were female. The most common clinical features included in the IPAF criteria were arthritis (82%) and Raynaud’s phenomenon (26%). A morbilliform and/or polymorphic rash of the face, neck and extremities (not included in the IPAF criteria) was noted in 54% of patients. ANA (59%) and anti–Ro (21%) were the most common auto-antibodies. Non-specific Interstitial Pneumonia (NSIP) was the most prevalent radiological pattern (61.5%) as shown in table 1. Treatment comprised corticosteroids and immunosuppressants including hydroxychloroquine, methotrexate, azathioprine, mycophenolate and cyclophosphamide. PFTs following treatment at 6 and 12 months from baseline showed a trend of improvement (Table 2, p> 0.05). At 1 year from baseline, 20.5% of patients showed a clinically significant deterioration while 25% had a clinically significant improvement. Infections were observed in 23.1% of patients during the first semester and in 12.8% during the second semester of the follow-up period. All were respiratory tract infections and two patients (5.1%) required hospitalization. All infections occurred in patients with non-UIP pattern (p=0.02) which might be attributed to higher doses of corticosteroids used in these patients (mean initial prednisolone dose = 27 (±18) mg/d in patients with non-UIP pattern versus 17 (±16) mg/d in patients with UIP pattern, p=0.4).

Table 1.

Prevalence of HRCT patterns in 39 patients.

Radiological patternNo (%)NSIP24 (61,5%)OP2 (5,1%)NSIP with OP overlap2 (5,1%)LIP1 (2,6%)UIP7 (18%)NSIP and UIP3 (7,7%)

NSIP: Non-specific Interstitial Pneumonia, OP: Organizing Pneumonia, LIP: Lymphocytic Interstitial Pneumonia, UIP: Usual Interstitial Pneumonia.

Table 2.

PFTs at baseline, 6 and 12 months.

PFTs (% of predicted value ± SD)Baseline6 months12 monthsP valueFVC79% (±19%)82% (±18%)84% (±17%)nsDLCO49% (±16%)52% (±17%)53% (±17%)ns

Conclusion:

Rash is a common feature in IPAF and may be considered for inclusion into IPAF criteria. A trend of improvement in PFTs and a significant risk of respiratory tract infections mainly in the first semester of treatment and in patients with non-UIP radiological pattern were observed. Larger prospective studies are warranted in order to elucidate IPAF’s prognosis and to identify effective management approaches.

References:

[1]Fischer A, et al. An official European Respiratory Society/American Thoracic Society research statement: interstitial pneumonia with autoimmune features. Eur Respir J 2015; 46: 976-987.

Disclosure of Interests:

Maria Karampeli: None declared, Konstantinos Thomas: None declared, Dimitrios Tseronis: None declared, Michail Aggelakos: None declared, Dimitra Kassara: None declared, Katerina Havatza: None declared, Sofia Flouda: None declared, Dionysis Nikolopoulos: None declared, Antigoni Pieta: None declared, Vasiliki Tzavara: None declared, Pelagia Katsimbri: None declared, Dimitrios Boumpas Grant/research support from: Unrestricted grant support from various pharmaceutical companies, Theofanis Karageorgas: None declared

Treatment of COVID-19 Patients with Convalescent Plasma in Houston, Texas

BACKGROUND

COVID-19 disease, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread globally, and no proven treatments are available. Convalescent plasma therapy has been used with varying degrees of success to treat severe microbial infections for more than 100 years.

METHODS

Patients (n=25) with severe and/or life-threatening COVID-19 disease were enrolled at the Houston Methodist hospitals from March 28 to April 14, 2020. Patients were transfused with convalescent plasma obtained from donors with confirmed SARS-CoV-2 infection and had been symptom free for 14 days. The primary study outcome was safety, and the secondary outcome was clinical status at day 14 post-transfusion. Clinical improvement was assessed based on a modified World Health Organization 6-point ordinal scale and laboratory parameters. Viral genome sequencing was performed on donor and recipient strains.

RESULTS

At baseline, all patients were receiving supportive care, including anti-inflammatory and anti-viral treatments, and all patients were on oxygen support. At day 7 post-transfusion with convalescent plasma, nine patients had at least a 1-point improvement in clinical scale, and seven of those were discharged. By day 14 post-transfusion, 19 (76%) patients had at least a 1-point improvement in clinical status and 11 were discharged. No adverse events as a result of plasma transfusion were observed. The whole genome sequencing data did not identify a strain genotype-disease severity correlation.

CONCLUSIONS

The data indicate that administration of convalescent plasma is a safe treatment option for those with severe COVID-19 disease. Randomized, controlled trials are needed to determine its efficacy.

Maintenance of clinical remission in early axial spondyloarthritis following certolizumab pegol dose reduction

Background

The best strategy for maintaining clinical remission in patients with axial spondyloarthritis (axSpA) has not been defined. C-OPTIMISE compared dose continuation, reduction and withdrawal of the tumour necrosis factor inhibitor certolizumab pegol (CZP) following achievement of sustained remission in patients with early axSpA.

Methods

C-OPTIMISE was a two-part, multicentre phase 3b study in adults with early active axSpA (radiographic or non-radiographic). During the 48-week open-label induction period, patients received CZP 200 mg every 2 weeks (Q2W). At Week 48, patients in sustained remission (Ankylosing Spondylitis Disease Activity Score (ASDAS) <1.3 at Weeks 32/36 and 48) were randomised to double-blind CZP 200 mg Q2W (full maintenance dose), CZP 200 mg every 4 weeks (Q4W; reduced maintenance dose) or placebo (withdrawal) for a further 48 weeks. The primary endpoint was remaining flare-free (flare: ASDAS ≥2.1 at two consecutive visits or ASDAS >3.5 at any time point) during the double-blind period.

Results

At Week 48, 43.9% (323/736) patients achieved sustained remission, of whom 313 were randomised to CZP full maintenance dose, CZP reduced maintenance dose or placebo. During Weeks 48 to 96, 83.7% (87/104), 79.0% (83/105) and 20.2% (21/104) of patients receiving the full maintenance dose, reduced maintenance dose or placebo, respectively, were flare-free (p<0.001 vs placebo in both CZP groups). Responses in radiographic and non-radiographic axSpA patients were comparable.

Conclusions

Patients with early axSpA who achieve sustained remission at 48 weeks can reduce their CZP maintenance dose; however, treatment should not be completely discontinued due to the high risk of flare following CZP withdrawal.

Trial registration number

NCT02505542, ClinicalTrials.gov.

Treatment modalities and drug survival in a systemic sclerosis real-life patient cohort

BACKGROUND

European data indicate that systemic sclerosis (SSc)-related death rates are increasing, thus raising concerns about SSc's optimal management. Herein, we describe current treatment modalities and drug survival in a real-life SSc cohort.

METHODS

Details on immunosuppressive/antiproliferative (methotrexate, mycophenolate, cyclophosphamide, azathioprine, rituximab, tocilizumab) and vasoactive agent [(endothelin receptor antagonists (ERAs), sildenafil, iloprost, and calcium channel blockers (CCB)] administration during the disease course (11.8 ± 8.4 years, mean + SD) of 497 consecutive patients examined between 2016 and 2018 were retrospectively recorded. Drug survival was assessed by Kaplan-Meier analysis.

RESULTS

Methotrexate was the most frequently administered immunosuppressive/antiproliferative agent (53% of patients), followed by cyclophosphamide (26%), mycophenolate (12%), and azathioprine (11%). Regarding vasoactive agents, CCB had been ever administered in 68%, ERAs in 38%, iloprost in 7%, and sildenafil in 7% of patients; 23% of patients with pulmonary fibrosis had never received immunosuppressive/antiproliferative agents, 33% of those with digital ulcers had never received ERAs, iloprost, or sildenafil, whereas 19% of all patients had never received either immunosuppressive/antiproliferative or other than CCB vasoactive agents. Survival rates of methotrexate, cyclophosphamide, and mycophenolate differed significantly, being 84/75%, 59/43%, and 74/63% at 12/24 months, respectively, with inefficacy being the most frequent discontinuation cause. Conversely, CCB, ERAs, and sildenafil had high and comparable retention rates of 97/91%, 88/86%, and 80/80%, respectively.

CONCLUSIONS

Existing therapeutic limitations indicate that more evidence-based treatment is warranted for successful management of SSc. Vasculopathy seems to be managed more rigorously, but the low retention rates of immunosuppressive/antiproliferative drugs suggest that effective and targeted disease-modifying agents are warranted.

Standard and Hypofractionated Dose Escalation to Intraprostatic Tumor Nodules in Localized Prostate Cancer: Efficacy and Toxicity in the DELINEATE Trial

PURPOSE

To report a planned analysis of the efficacy and toxicity of dose escalation to the intraprostatic dominant nodule identified on multiparametric magnetic resonance imaging using standard and hypofractionated external beam radiation therapy.

METHODS AND MATERIALS

DELINEATE is a single centre prospective phase 2 multicohort study including standard (cohort A: 74 Gy in 37 fractions) and moderately hypofractionated (cohort B: 60 Gy in 20 fractions) prostate image guided intensity modulated radiation therapy in patients with National Comprehensive Cancer Network intermediate- and high-risk disease. Patients received an integrated boost of 82 Gy (cohort A) and 67 Gy (cohort B) to lesions visible on multiparametric magnetic resonance imaging. Fifty-five patients were treated in cohort A, and 158 patients were treated in cohort B; the first 50 sequentially treated patients in cohort B were included in this planned analysis. The primary endpoint was late Radiation Therapy Oncology Group rectal toxicity at 1 year. Secondary endpoints included acute and late toxicity measured with clinician- and patient-reported outcomes at other time points and biochemical relapse-free survival for cohort A. Median follow-up was 74.5 months for cohort A and 52.0 months for cohort B.

RESULTS

In cohorts A and B, 27% and 40% of patients, respectively, were classified as having National Comprehensive Cancer Network high-risk disease. The cumulative 1-year incidence of Radiation Therapy Oncology Group grade 2 or worse rectal and urinary toxicity was 3.6% and 0% in cohort A and 8% and 10% in cohort B, respectively. There was no reported late grade 3 rectal toxicity in either cohort. Within cohort A, 4 of 55 (7%) patients had biochemical relapse.

CONCLUSIONS

Delivery of a simultaneous integrated boost to intraprostatic dominant nodules is feasible in prostate radiation therapy using standard and moderately hypofractionated regimens, with rectal and genitourinary toxicity comparable to contemporary series without an intraprostatic boost.

Effect of Reduced Exposure to Vasopressors on 90-Day Mortality in Older Critically Ill Patients With Vasodilatory Hypotension: A Randomized Clinical Trial

Importance

Vasopressors are commonly administered to intensive care unit (ICU) patients to raise blood pressure. Balancing risks and benefits of vasopressors is a challenge, particularly in older patients.

Objective

To determine whether reducing exposure to vasopressors through permissive hypotension (mean arterial pressure [MAP] target, 60-65 mm Hg) reduces mortality at 90 days in ICU patients aged 65 years or older with vasodilatory hypotension.

Design, Setting, and Participants

A multicenter, pragmatic, randomized clinical trial was conducted in 65 ICUs in the United Kingdom and included 2600 randomized patients aged 65 years or older with vasodilatory hypotension (assessed by treating clinician). The study was conducted from July 2017 to March 2019, and follow-up was completed in August 2019.

Interventions

Patients were randomized 1:1 to vasopressors guided either by MAP target (60-65 mm Hg, permissive hypotension) (n = 1291) or according to usual care (at the discretion of treating clinicians) (n = 1307).

Main Outcome and Measures

The primary clinical outcome was all-cause mortality at 90 days.

Results

Of 2600 randomized patients, after removal of those who declined or had withdrawn consent, 2463 (95%) were included in the analysis of the primary outcome (mean [SD] age 75 years [7 years]; 1387 [57%] men). Patients randomized to the permissive hypotension group had lower exposure to vasopressors compared with those in the usual care group (median duration 33 hours vs 38 hours; difference in medians, -5.0; 95% CI, -7.8 to -2.2 hours; total dose in norepinephrine equivalents median, 17.7 mg vs 26.4 mg; difference in medians, -8.7 mg; 95% CI, -12.8 to -4.6 mg). At 90 days, 500 of 1221 (41.0%) in the permissive hypotension compared with 544 of 1242 (43.8%) in the usual care group had died (absolute risk difference, -2.85%; 95% CI, -6.75 to 1.05; P = .15) (unadjusted relative risk, 0.93; 95% CI, 0.85-1.03). When adjusted for prespecified baseline variables, the odds ratio for 90-day mortality was 0.82 (95% CI, 0.68 to 0.98). Serious adverse events were reported for 79 patients (6.2%) in the permissive care group and 75 patients (5.8%) in the usual care group. The most common serious adverse events were acute renal failure (41 [3.2%] vs 33 [2.5%]) and supraventricular cardiac arrhythmia (12 [0.9%] vs 13 [1.0%]).

Conclusions and Relevance

Among patients 65 years or older receiving vasopressors for vasodilatory hypotension, permissive hypotension compared with usual care did not result in a statistically significant reduction in mortality at 90 days. However, the confidence interval around the point estimate for the primary outcome should be considered when interpreting the clinical importance of the study.

Trial Registration

isrctn.org Identifier: ISRCTN10580502.

The Intensity-Modulated Pelvic Node and Bladder Radiotherapy (IMPART) Trial: A Phase II Single-Centre Prospective Study

AIMS

Node-positive bladder cancer (NPBC) carries a poor prognosis and has traditionally been treated palliatively. However, surgical series suggest that a subset of NPBC patients can achieve long-term control after cystectomy and lymph node dissection. There is little published data regarding the use of radiotherapy to treat NPBC patients. This is in part due to concerns regarding the toxicity of whole-pelvis radiotherapy using conventional techniques. We hypothesised that, using intensity-modulated radiotherapy (IMRT), the pelvic nodes and bladder could be treated within a radical treatment volume with acceptable toxicity profiles.

MATERIALS AND METHODS

The Intensity-modulated Pelvic Node and Bladder Radiotherapy (IMPART) trial was a phase II single-centre prospective study designed to assess the feasibility of delivering IMRT to treat the bladder and pelvic nodes in patients with node-positive or high-risk node-negative bladder cancer (NNBC). The primary end point was meeting predetermined dose constraints. Secondary end points included acute and late toxicity, pelvic relapse-free survival and overall survival.

RESULTS

In total, 38 patients were recruited and treated between June 2009 and November 2012; 22/38 (58%) had NPBC; 31/38 (81.6%) received neoadjuvant chemotherapy; 18/38 (47%) received concurrent chemotherapy; 37/38 (97%) patients had radiotherapy planned as per protocol. Grade 3 gastrointestinal and genitourinary acute toxicity rates were 5.4 and 20.6%, respectively. At 1 year, the grade 3 late toxicity rate was 5%; 1-, 2- and 5-year pelvic relapse-free survival rates were 55, 37 and 26%, respectively. The median overall survival was 1.9 years (95% confidence interval 1.1-3.8) with 1-, 2- and 5-year overall survival rates of 68, 50 and 34%, respectively.

CONCLUSION

Delivering IMRT to the bladder and pelvic nodes in NPBC and high-risk NNBC is feasible, with low toxicity and low pelvic nodal recurrence rates. Long-term control seems to be achievable in a subset of patients. However, relapse patterns suggest that strategies targeting both local recurrence and the development of distant metastases are required to improve patient outcomes.

Conceptualising post-stroke fatigue: a cross-sectional survey of UK-based physiotherapists and occupational therapists

With survival after stroke improving, more people are discharged into the community with multiple and persistent deficits. Fatigue is a common unmet need for stroke survivors, but there are no evidence-based guidelines for its assessment and management. This study explored how UK-based therapists conceptualise post-stroke fatigue (PSF) in current practice.

OBJECTIVE

To describe current understanding of PSF among physiotherapists (PT) and occupational therapists (OT).

DESIGN

A cross-sectional online survey using Qualtrics software (a survey creation and analysis programme) was sent to therapists working with stroke survivors in 2019. Responses to the open ended question, 'How would you describe PSF if approached by another healthcare professional?' were analysed thematically by two independent researchers.

PARTICIPANTS

137 survey respondents (71 PT and 66 OT) from a range of clinical settings (25 acute care, 24 sub-acute rehabilitation care, 3 primary care and 85 community care) with 7 months-36 years of experience working with stroke survivors completed the survey.

RESULTS

Respondents stated that PSF should be regarded as an important medical condition because it is common and can be associated with severe symptoms. Symptoms were perceived to be highly variable and the syndrome was difficult to define objectively. It was felt to have both physical and cognitive components. A variety of different opinions were expressed with regard to causation, conceptualisation and best management.

CONCLUSION

Therapists working with stroke survivors conceptualise and manage PSF in different ways. Clinical practice is hampered by a lack of a widely adopted definition, and a small evidence base. Research into causes and management of PSF is a priority.

Validation of T2- and diffusion-weighted magnetic resonance imaging for mapping intra-prostatic tumour prior to focal boost dose-escalation using intensity-modulated radiotherapy (IMRT)

BACKGROUND AND PURPOSE

To assess the diagnostic accuracy and inter-observer agreement of T2-weighted (T2W) and diffusion-weighted (DW) magnetic resonance imaging (MRI) for mapping intra-prostatic tumour lesions (IPLs) for the purpose of focal dose-escalation in prostate cancer radiotherapy.

MATERIALS AND METHODS

Twenty-six men selected for radical treatment with radiotherapy were recruited prospectively and underwent pre-treatment T2W+DW-MRI and 5 mm spaced transperineal template-guided mapping prostate biopsies (TTMPB). A 'traffic-light' system was used to score both data sets. Radiologically suspicious lesions measuring ≥0.5 cm3 were classified as red; suspicious lesions 0.2-0.5 cm3 or larger lesions equivocal for tumour were classified as amber. The histopathology assessment combined pathological grade and tumour length on biopsy (red = ≥4 mm primary Gleason grade 4/5 or ≥6 mm primary Gleason grade 3). Two radiologists assessed the MRI data and inter-observer agreement was measured with Cohens' Kappa co-efficient.

RESULTS

Twenty-five of 26 men had red image-defined IPLs by both readers, 24 had red pathology-defined lesions. There was a good correlation between lesions ≥0.5 cm3 classified "red" on imaging and "red" histopathology in biopsies (Reader 1: r = 0.61, p < 0.0001, Reader 2: r = 0.44, p = 0.03). Diagnostic accuracy for both readers for red image-defined lesions was sensitivity 85-86%, specificity 93-98%, positive predictive value (PPV) 79-92% and negative predictive value (NPV) 96%. Inter-observer agreement was good (Cohen's Kappa 0.61).

CONCLUSIONS

MRI is accurate for mapping clinically significant prostate cancer; diffusion-restricted lesions ≥0.5 cm3 can be confidently identified for radiation dose boosting.

Antimicrobial Resistance in Retail Ground Beef with and Without a “Raised Without Antibiotics” Claim

ObjectivesThe occurrences of human bacterial infections complicated by antimicrobial resistance (AMR) have increased in recent decades. Concerns have been raised that food-animal production practices that incorporate antimicrobials contribute significantly to human AMR exposures since food-animal production accounts for approximately 81% of U.S. antimicrobial consumption by mass. Although empirical studies comparing AMR levels in meat products, including ground beef, are scant ground beef products with Raised without Antibiotics (RWA) label claims are perceived to harbor less AMR than “conventional” (CONV) products with no label claims regarding antimicrobial use. The objective of this research was to determine AMR levels in retail ground beef with and without an RWA label claims.Materials and MethodsRetail ground beef samples were obtained from 6 U.S. cities. Samples were obtained on the following dates: 9/18/2017, 10/30/2017, 11/27/2017. 1/29/2018. 3/5/2018, and 6/11/2018. A total of 599 samples were obtained. Samples with a “Raised without Antibiotics” or USDA Organic claim (N = 299) were assigned to the RWA production system. Samples lacking a “Raised without Antibiotics” claim (N = 300) were assigned to the CONV production system. Each sample was cultured for the detection of five antimicrobial resistant bacteria (ARB). Genomic DNA was isolated from each sample and qPCR was used to determine the abundance of ten antimicrobial resistance genes (ARGs). The impacts of production system and city on ARB detection were assessed by the Likelihood-ratio chi-squared test. The impacts of production system and city on ARG abundance was assessed by two-way ANOVA.ResultsTetracycline-resistant Escherichia coli (CONV = 46.3%; RWA = 34.4%) and erythromycin-resistant Enterococcus (CONV = 48.0%; RWA = 37.5%) were more frequently (P < 0.01) detected in CONV. Detection of third generation cephalosporin-resistant E. coli (CONV = 5.7%; RWA = 1.0%), vancomycin-resistant Enterococcus (CONV = 0.0%; RWA = 0.0%) and methicillin-resistant Staphylococcus aureus (CONV = 1.3%; RWA = 0.7%) did not differ (P = 1.00). The blaCTX-M ARG was more abundant in CONV (2.4 vs. 2.1 log copies/gram, P = 0.01) but the tet(A) (2.4 vs. 2.5 log copies/gram, P = 0.02) and tet(M) (3.6 vs. 3.9 log copies/gram, P < 0.01) ARGs were more abundant in RWA. aadA1, blaCMY-2, mecA, erm(B), and tet(B) abundances did not differ significantly (Fig. 5) (P > 0.05). Abundances of aac (6’)-Ie-aph (2”)-Ia and blaKPC-2 were not analyzed since they were quantified in less than 5% of the samples.ConclusionU.S. retail CONV and RWA ground beef harbor generally similar levels of AMR since only 5 of 15 AMR measurements were statistically different between production systems. Three AMR measurements were higher in CONV, while 2 AMR measurements were higher in RWA. These results are in general agreement with a recently published study authored by our group that examined antimicrobial resistance in CONV and RWA ground beef obtained from U.S. foodservice suppliers (Vikram et al., J. Food Prot. 81:2007–2018. 2018.). Together these studies suggest that antimicrobial use during U.S. cattle production has minimal to no impact on human exposure to AMR via ground beef.Figure 5.

1157. GET IT OUT! Nurses and Clinical Quality Improvement Specialists Drive Initiative to Reduce Standardized Utilization Ratios for Indwelling Urinary Catheters in Hospitalized Patients

Background

Urinary tract infections (UTIs) account for 34% of all healthcare-associated infections (HAI). Urinary catheters (UC) are placed in 15–25% of hospitalized patients and >75% of HAI UTIs are UC-related. Bacteria introduced via UC can colonize the bladder within 3 days. So, the greatest risk factor for acquiring a catheter-associated urinary tract infection (CAUTI) is prolonged use of indwelling UC. Nursing (RN) staff noted inconsistency with appropriate use of UC and commonly UC remained in place well after their original indication had expired.

Methods

As part of a multi-faceted approach for quality improvement and patient safety, we rolled out an Agency for Healthcare Research and Quality (AHRQ)-based initiative to reduce UC days/Standardized Utilization Ratio (SUR). Daily critical reviews of the indication for UC were conducted by two groups. First, frontline night shift RN staff identified patients who no longer had a valid justification for continued UC. They handed-off the information to day-shift RNs, who recommend removal of UC during daily rounds with the physician teams. A second review was performed by Clinical Quality Improvement Specialists (CQIS) based on defined criteria from our nursing decatheterization protocol. Their discontinue UC recommendations were also sent to the care teams. The critical reviews of UC for CAUTI reduction started with 4 ICUs in August 2018, with additional ICUs added in December, January and March. Monthly UC SURs were tracked

Results

Figure 1 shows the number of UCs recommended for removal by RNs vs. CQIS (bars), as well as the percent discordance between RNs and CQIS (line). CQIS identified many more removable UCs than the RNs (888 vs. 256). 211 UC were removed after RN recommendations, and an additional 386 UCs were removed as a result of the CQIS audits. Figure 2 shows the marked corresponding decline in our SUR over this intervention.

Conclusion

As more units participated in the initiative, we saw increasing numbers of “discontinue UC” recommendations. Over time there was also a moderate decrease in the discordance between RN and CQIS recommendations for UC removal. CQIS routinely identified many more UCs to be removed compared with RNs, and more than doubled the number of discontinued UC. Notably, the UC SUR markedly improved, decreasing from 0.98 to 0.78.

Disclosures

All authors: No reported disclosures.

A-42 Case of Persistent Amnestic Syndrome due to Small Right-Sided Retrosplenial Lacunes

Objective

Lesions to the retrosplenial cortex secondary to acute stroke or tumor have been shown to disrupt Papez’s circuit due to disconnection between the anterior thalamus and hippocampus, via the posterior cingulate, producing an amnestic syndrome. This case demonstrates how small but strategic lacunes in this region may produce memory deficits.

Method

The patient is a 52-year-old, right-handed, African-American woman with 18 years of education who reported memory changes over the last 8 years (e.g., misplacing items, forgetting details of conversations). Her medical history was notable for BMI of 31 and borderline diabetes. She completed structural magnetic resonance imaging 6 years prior to, and concordant with, her neuropsychological evaluation. Both scans showed two small (2-3 mm) right-sided retrosplenial lacunes, without evidence of hippocampal or global volume loss over the 6-year span.

Results

Her neurocognitive profile was characterized by impairments in both verbal (stories, word-list) and figural memory, with relative strengths in attention, processing speed, and executive functioning. Across memory measures, she performed in the low average-to-mildly impaired range on immediate recall, mildly-to-severely impaired range on delayed recall, and did not benefit from yes-no recognition format. She demonstrated additional features of an amnestic profile, including flat learning slope, recency effect, elevated cued recall intrusion errors, and very elevated false positive errors on recognition.

Conclusions

Findings expand upon the existing literature to show that chronic, small retrosplenial lacunes can disrupt the connection between the anterior thalamus and hippocampus, resulting in a clinical presentation of circumscribed memory impairment that persists years beyond acute vascular changes.

Snake envenomation: is the 20 min whole blood clotting test (WBCT20) the optimum test for management?

BACKGROUND

The 20 min whole blood clotting test (WBCT20) is a simple bedside test recommended by World Health Organization (WHO) to assess hemotoxic envenomation and guide administration of polyvalent anti-snake venom (ASV). However, reliability and validity of this test has not been well documented in literature.

METHODS

Sixty consecutive patients with history of snake bite were prospectively evaluated at a teaching hospital in India over 2 years. Envenomation was established by clinical and laboratory criteria. WBCT20 was done at 0, 4 and 12 h using standardized protocol. Prothrombin time (PT) with international normalized ratio (INR) was estimated at similar intervals to detect venom-induced consumption coagulopathy. Sensitivity, specificity and likelihood ratios (LR) were determined for WBCT20 using envenomation criteria as gold standard. WBCT20 was compared with PT/INR at cutoff values of ≥1.4 and ≥1.2. Two observers performed test-retest correlation to determine inter-observer variability of WBCT20.

RESULTS

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Seventeen of 60 patients had evidence of hemotoxic envenomation. Four patients had combined neurotoxicity and hemotoxicity. Sensitivity and specificity of WBCT20 were 94 and 76%; positive and negative LR were 3.9 and 0.08, respectively. No inter-observer variability was noted.

CONCLUSIONS

WBCT20 is a highly sensitive test with excellent reliability for detecting envenomation. However, the false positive rate in this study was 24%. Asymptomatic snake bite patients with a positive WBCT20 but no corresponding clinical signs of envenomation should be tested using PT/INR before receiving ASV to prevent unnecessary waste of anti-venom.