Role of IP-10 to predict clinical progression and response to IL-6 blockade with Sarilumab in early COVID-19 pneumonia. A subanalysis of the SARICOR clinical trial

Background

Clinical Trial of Sarilumab in Adults With COVID-19 (SARICOR) showed that patients with COVID-19 pneumonia and increased levels of interleukin (IL)-6 might benefit from blockade of IL6-pathway. However, the benefit from this intervention might not be uniform. In this subanalysis, we sought to determine if other immunoactivation markers, besides IL-6, could identify which subgroup of patients benefit the most of this intervention.

Methodology

The SARICOR trial was a phase II, open-label, multicentre, controlled (July 2020-March 2021) in which patients were randomized to receive usual care (UC) (control group); UC plus single dose of Sarilumab 200 mg (Sarilumab-200 group) or UC plus single dose of Sarilumab 400 mg (Sarilumab-400 group). Patients who had baseline serum samples for cytokine determination (IL-8, IL-10, MCP-1, IP-10) were included in this secondary analysis. Progression to ARDS according to cytokine levels and treatment received was evaluated.

Results

101 (88%) of 115 patients enrolled in the SARICOR trial had serum samples (control group: n=33; Sarilumab-200: n=33; Sarilumab-400 n=35). Among all evaluated biomarkers, IP-10 showed the strongest association with treatment outcome. Patients with IP-10 ≥ 2500 pg/ml treated with Sarilumab-400 had a lower probability of progression (13%) compared to the control group (58%) (HR 0.19; 95% CI: 0.04-0.90; p=0.04). Conversely, patients with IP-10 < 2500 pg/ml did not show these differences.

Conclusions

IP-10 may predict progression to ARDS in patients with COVID-19 pneumonia and IL-6 levels > 40 pg/ml. Importantly, IP-10 value < 2500 pg/ml might discriminate those individuals who might not benefit of Sarilumab therapy besides high IL-6 levels.

OP0231 MASS CYTOMETRY DATA RECLASSIFY SYSTEMIC AUTOIMMUNE DISEASE PATIENTS IN PHENOTYPICALLY DISTINCTIVE GROUPS

Background

Systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSC), Sjögren’s syndrome (SJS), mixed connective tissue disease (MCTD), primary antiphospholipid syndrome (PAPS) and undifferentiated connective tissue disease (UCTD) are classified as systemic autoimmune diseases (SADs). They are diagnosed based on different clinical and laboratory criteria. Due to their high internal heterogeneity and overlapping symptoms, SADs are difficult to diagnose. Therefore, molecular and cellular-based studies need to be undertaken to precisely classify the patients. Mass cytometry is a single-cell proteomics technology that measures approximately 50 markers per cell, thus it is a suitable tool to perform deep-phenotyping studies in SADs.

Objectives

Explore differences and similarities between SADs and build reclassification framework using high-dimensional cytometry data.

Methods

The whole blood samples collected from 129 individuals, including patients and controls were stained with a 39-plex antibody panel and acquired in 9 batches on a CyTOF (HELIOS) instrument. Data were cleaned, and normalized for batch effects using semi-automated cytof analysis pipeline. Cell frequencies and median signal intensities (MSI) for each population were extracted using FlowSOM for mononuclear cells (PBMC) and Phenograph for granulocytes. Secretion of 44 cytokines and chemokines were analyzed using a multiplexed luminex assay. Diseases were compared by Kruskal-Wallis analysis and hierarchical clustering and reclassification was done using unsupervised k-means clustering. Cytokine analysis across clusters was performed using Kruskal-Wallis test.

Results

Differently expressed features were observed between patient groups, regarding frequency of classical monocytes, B and T cells subpopulations, mature and immature granulocytes and intensities of CD38, HLA-DR and CD95 across various populations. However, none of them were disease specific. K-means clustering identified four patient clusters, which were composed by a mixture of different diagnosis. Cluster C1 was characterized by increased levels of circulating cells from PBMC compartment, and lower activation of different populations of the T cell compartment. It presented lower frequency in multiple granulocyte populations and the highest expression of CD95 and CD38. This cluster was also associated with antimalarial and steroid treatment. Clusters C1 and C2 were exactly opposite to each other, cluster C3 was characterized by intermediate features between C1 and C2 and cluster C4 could be considered as undifferentiated, mixed group. Higher production of TNFα, IL-10 and IP-10 were found in patients from C1 compared to C2, suggesting more active phenotype in C1 and physiological one in C2. The cytokine levels were independent of the treatment.

Conclusion

We constructed a patient reclassification framework using cell frequencies and expression levels of functional markers. To our knowledge this is the first time when 7 different SADs were compared using mass cytometry. In agreement with other reports we did not detect any disease-specific cellular markers. Distribution of diagnosis across different clusters confirms diseases heterogeneity. Patients can be classified into phenotypically similar groups, that could potentially benefit from the same line of treatment.

Acknowledgements

This project has received funding from the Innovative Medicines Initiative 2 Joint Undertaking (JU) under grant agreement No 831434 (3TR) and The JU receives support from the European Union’s Horizon 2020 research and innovation programme and EFPIA. Also from No 115565 PRECISESADS.

Disclosure of Interests

None declared

[Performance of the KAtex test in screening and diagnosis for visceral leishmaniasis in a reference hospital]

OBJECTIVE

Performing of diagnostic test simple using samples not invasive in the diagnosis of visceral leishmaniasis (VL) may be very beneficial, being necessary comparing to traditional methods. The objective of this study was to know the reliability of test KAtex in the urine of patients with suspicion of VL.

METHODS

Retrospectively were reviewed the medical histories of patients with suspected of VL to which are performed the test between 2009 and 2015. For its analysis were selected the patients to which is them had made study of the parasite in bone marrow.

RESULTS

A total of 110 patients were studied, and bone marrow biopsy for research of Leishmania was performed in 44 (40%). In these patients the sensitivity of the test was 50%, the specificity of 96.7%, positive predictive value of 87.5% and negative predictive value of 80.5%.

CONCLUSIONS

KAtex antigenuria sensitivity is too low recommending it as a unique method in the detection of VL in our medium.

IFI44L promoter methylation as a blood biomarker for systemic lupus erythematosus

OBJECTIVE

Systemic lupus erythematosus (SLE) is a clinically heterogeneous disease with limited reliable diagnostic biomarkers. We investigated whether gene methylation could meet sensitivity and specificity criteria for a robust biomarker.

METHODS

IFI44L promoter methylation was examined using DNA samples from a discovery set including 377 patients with SLE, 358 healthy controls (HCs) and 353 patients with rheumatoid arthritis (RA). Two independent sets including 1144 patients with SLE, 1350 HCs, 429 patients with RA and 199 patients with primary Sjögren's syndrome (pSS) were used for validation.

RESULTS

Significant hypomethylation of two CpG sites within IFI44L promoter, Site1 (Chr1: 79 085 222) and Site2 (Chr1: 79 085 250; cg06872964), was identified in patients with SLE compared with HCs, patients with RA and patients with pSS. In a comparison between patients with SLE and HCs included in the first validation cohort, Site1 methylation had a sensitivity of 93.6% and a specificity of 96.8% at a cut-off methylation level of 75.5% and Site2 methylation had a sensitivity of 94.1% and a specificity of 98.2% at a cut-off methylation level of 25.5%. The IFI44L promoter methylation marker was also validated in an European-derived cohort. In addition, the methylation levels of Site1 and Site2 within IFI44L promoter were significantly lower in patients with SLE with renal damage than those without renal damage. Patients with SLE showed significantly increased methylation levels of Site1 and Site2 during remission compared with active stage.

CONCLUSIONS

The methylation level of IFI44L promoter can distinguish patients with SLE from healthy persons and other autoimmune diseases, and is a highly sensitive and specific diagnostic marker for SLE.

Bone mass and vitamin D in patients with systemic sclerosis from two Spanish regions

OBJECTIVES

To study the bone mass in patients with scleroderma (SSc) from two different Spanish regions and to evaluate the prevalence of vitamin D deficiency and insufficiency in this population and its possible relation to bone mineral density (BMD).

METHODS

Disease, bone mineral density related variables and vitamin D were collected from all patients. Statistical analysis was carried out using the SPSS 17 statistics software for Windows. A p<0.05 was considered significant.

RESULTS

A Z-score <-1 was found in 21.9% of the control population and 43% of SSc patients. The prevalence of osteopenia/osteoporosis was 50% in the control population and 77% in SSc (p<0.0001). We did not find differences between the prevalence of low BMD in the south (79%) and in the north of Spain (76.3%); but patients from the north had lower levels of vitamin D (27.4±16.2 ng/dL vs. 20.7±11.0 ng/dl; p<0.031). Low levels of vitamin D (<30ng/ml) were found in 69 patients out of 90, ten of them with insufficiency (<10ng/ml). Eighty-four point six percent of the patients with low levels of vitamin D (<30ng/ml) had LBMD compared whith 66.7% of those with normal levels (p=0.073).

CONCLUSIONS

The prevalence of osteoporosis/osteopenia in Spanish patient with SSc is very high. Although there are a high prevelence of vitamin D deficiency, we could not demonstrate a relationship of vitamin D deficiency with low mineral density.

[Meningitis by Toscana virus in Spain: description of 17 cases]

BACKGROUND AND OBJECTIVE

We aimed to analyze the clinical and epidemiological data from the first series of patients with meningitis by Toscana virus in Spain.

PATIENTS AND METHOD

We analyzed a total of 724 cerebrospinal fluid (CSF) samples from patients with suspicion of aseptic meningitis for virus isolation in cell culture. The clinical records of patients in whom Toscana virus was isolated were analyzed.

RESULTS

Toscana virus was isolated in CSF in 17 patients (7% of all viral isolates). The first case was diagnosed in June 1988 and the last one in August 2002. The mean age was 27 years (range: 10-64 years). Most patients were based in rural area (n = 11, 64.7%). Most common symptoms were headache (holocranial or focal) present in all patients and moderate fever observed in 76.5% of them with a mean duration of 48 h (range: 18 h-5 days). Nuchal rigidity was present in 9 patients (53%). All cases were seen between June and October, and predominantly in August (53%). The outcome was favorable in all cases, and the mean time of duration of the disease was 7 days (range: 3-10 days).

CONCLUSIONS

Toscana virus must be taken into account among those agents responsible of lymphocytic meningitis in Spain.

[Meningitis by Toscana virus in Spain: description of 17 cases]

BACKGROUND AND OBJECTIVE

We aimed to analyze the clinical and epidemiological data from the first series of patients with meningitis by Toscana virus in Spain.

PATIENTS AND METHOD

We analyzed a total of 724 cerebrospinal fluid (CSF) samples from patients with suspicion of aseptic meningitis for virus isolation in cell culture. The clinical records of patients in whom Toscana virus was isolated were analyzed.

RESULTS

Toscana virus was isolated in CSF in 17 patients (7% of all viral isolates). The first case was diagnosed in June 1988 and the last one in August 2002. The mean age was 27 years (range: 10-64 years). Most patients were based in rural area (n = 11, 64.7%). Most common symptoms were headache (holocranial or focal) present in all patients and moderate fever observed in 76.5% of them with a mean duration of 48 h (range: 18 h-5 days). Nuchal rigidity was present in 9 patients (53%). All cases were seen between June and October, and predominantly in August (53%). The outcome was favorable in all cases, and the mean time of duration of the disease was 7 days (range: 3-10 days).

CONCLUSIONS

Toscana virus must be taken into account among those agents responsible of lymphocytic meningitis in Spain.