Monthly Global Estimates of Fine Particulate Matter and Their Uncertainty.

Annual global satellite-based estimates of fine particulate matter (PM2.5) are widely relied upon for air-quality assessment. Here, we develop and apply a methodology for monthly estimates and uncertainties during the period 1998-2019, which combines satellite retrievals of aerosol optical depth, chemical transport modeling, and ground-based measurements to allow for the characterization of seasonal and episodic exposure, as well as aid air-quality management. Many densely populated regions have their highest PM2.5 concentrations in winter, exceeding summertime concentrations by factors of 1.5-3.0 over Eastern Europe, Western Europe, South Asia, and East Asia. In South Asia, in January, regional population-weighted monthly mean PM2.5 concentrations exceed 90 µg/m3, with local concentrations of approximately 200 µg/m3 for parts of the Indo-Gangetic Plain. In East Asia, monthly mean PM2.5 concentrations have decreased over the period 2010-2019 by 1.6-2.6 µg/m3/year, with decreases beginning 2-3 years earlier in summer than in winter. We find evidence that global-monitored locations tend to be in cleaner regions than global mean PM2.5 exposure, with large measurement gaps in the Global South. Uncertainty estimates exhibit regional consistency with observed differences between ground-based and satellite-derived PM2.5. The evaluation of uncertainty for agglomerated values indicates that hybrid PM2.5 estimates provide precise regional-scale representation, with residual uncertainty inversely proportional to the sample size.

Global Estimates and Long-Term Trends of Fine Particulate Matter Concentrations (1998-2018).

Exposure to outdoor fine particulate matter (PM2.5) is a leading risk factor for mortality. We develop global estimates of annual PM2.5 concentrations and trends for 1998-2018 using advances in satellite observations, chemical transport modeling, and ground-based monitoring. Aerosol optical depths (AODs) from advanced satellite products including finer resolution, increased global coverage, and improved long-term stability are combined and related to surface PM2.5 concentrations using geophysical relationships between surface PM2.5 and AOD simulated by the GEOS-Chem chemical transport model with updated algorithms. The resultant annual mean geophysical PM2.5 estimates are highly consistent with globally distributed ground monitors (R2 = 0.81; slope = 0.90). Geographically weighted regression is applied to the geophysical PM2.5 estimates to predict and account for the residual bias with PM2.5 monitors, yielding even higher cross validated agreement (R2 = 0.90-0.92; slope = 0.90-0.97) with ground monitors and improved agreement compared to all earlier global estimates. The consistent long-term satellite AOD and simulation enable trend assessment over a 21 year period, identifying significant trends for eastern North America (-0.28 ± 0.03 µg/m3/yr), Europe (-0.15 ± 0.03 µg/m3/yr), India (1.13 ± 0.15 µg/m3/yr), and globally (0.04 ± 0.02 µg/m3/yr). The positive trend (2.44 ± 0.44 µg/m3/yr) for India over 2005-2013 and the negative trend (-3.37 ± 0.38 µg/m3/yr) for China over 2011-2018 are remarkable, with implications for the health of billions of people.

Reasons for inactive disease and flare in systemic onset juvenile idiopathic arthritis patients during tocilizumab treatment.

OBJECTIVES: The aim of our study was to evaluate disease courses and outcomes of sJIA children undergoing tocilizumab (TCZ) treatment, and to establish the predictors which distinguish inactive disease and disease flares. METHODS: Our retrospective study included 48 active sJIA children who were refractory to different anti-rheumatic drugs and who were then started on TCZ. The effectiveness of TCZ was assessed by the changes of sJIA attributed signs and symptoms and the remission was judged according to the Wallace (2004) criteria. RESULTS: The main demographic parameters (Me; IQR) were shown; mean age: 9.9 (5-12.7) years and mean duration of TCZ administration: 27.0 (5.9-89.7) months. During the TCZ treatment 40 cases (83.3%) achieved remission in 138.5 (56.0; 255.0) days. Patients who achieved remission had milder disease course, and presented less frequent epatosplenomegaly, lung, heart involvement and MAS. They had higher Hb and lower WBC, granulocytes, ESR, CRP, LDH, ferritin. The main predictors of achievement of inactive disease, calculated with Cox-regression models, were CRP≤82.0 mg/l (OR=7.9, HR=1.17), ESR≤32 mm/h (OR=17.0, HR=0.85), ferritin ≤273 ng/ml (OR=56.5, HR=2.6), Hb>113 g/l (OR=17.0, HR=1.33), LDH≤676 U/l (OR=113.6, HR=3.2), PLT>335*109/l (OR=5.0, HR=2.5), and intensive depression of WBC in 2 weeks after the 1st TCZ infusion>11% (OR=13.0, HR=6.0) and granulocytes>12% (OR=14.0, HR=4.7). CONCLUSIONS: sJIA children with milder disease course have more posssibilty of achieving disease remission during TCZ treatment. Male sex, signs of high disease activity, previous CS treatment, the long time needed to achieve inactive disease and treatment protocol deviations increased the risk of sJIA flare.

Estimating PM2.5 speciation concentrations using prototype 4.4 km-resolution MISR aerosol properties over Southern California.

Research efforts to better characterize the differential toxicity of PM2.5 (particles with aerodynamic diameters less than or equal to 2.5 µm) speciation are often hindered by the sparse or non-existent coverage of ground monitors. The Multi-angle Imaging SpectroRadiometer (MISR) aboard NASA's Terra satellite is one of few satellite aerosol sensors providing information of aerosol shape, size and extinction globally for a long and continuous period that can be used to estimate PM2.5 speciation concentrations since year 2000. Currently, MISR only provides a 17.6 km product for its entire mission with global coverage every 9 days, a bit too coarse for air pollution health effects research and to capture local spatial variability of PM2.5 speciation. In this study, generalized additive models (GAMs) were developed using MISR prototype 4.4 km-resolution aerosol data with meteorological variables and geographical indicators, to predict ground-level concentrations of PM2.5 sulfate, nitrate, organic carbon (OC) and elemental carbon (EC) in Southern California between 2001 and 2015 at the daily level. The GAMs are able to explain 66%, 62%, 55% and 58% of the daily variability in PM2.5 sulfate, nitrate, OC and EC concentrations during the whole study period, respectively. Predicted concentrations capture large regional patterns as well as fine gradients of the four PM2.5 species in urban areas of Los Angeles and other counties, as well as in the Central Valley. This study is the first attempt to use MISR prototype 4.4 km-resolution AOD (aerosol optical depth) components data to predict PM2.5 sulfate, nitrate, OC and EC concentrations at the sub-regional scale. In spite of its low temporal sampling frequency, our analysis suggests that the MISR 4.4 km fractional AODs provide a promising way to capture the spatial hotspots and long-term temporal trends of PM2.5 speciation, understand the effectiveness of air quality controls, and allow our estimated PM2.5 speciation data to be linked with common spatial units such as census tract or zip code in epidemiological studies. This modeling strategy needs to be validated in other regions when more MISR 4.4 km data becoming available in the future.

Methotrexate treatment may prevent uveitis onset in patients with juvenile idiopathic arthritis: experiences and subgroup analysis in a cohort with frequent methotrexate use.

OBJECTIVES: To re-evaluate the ability of methotrexate (MTX) to prevent the onset of uveitis in Russian children with juvenile idiopathic arthritis (JIA). METHODS: The clinical charts for all consecutive patients who received a stable management for at least 2 years with or without MTX were reviewed. Patients who were given systemic medications other than MTX (except NSAID) and patients with systemic arthritis, rheumatoid factor-positive arthritis, or enthesitis-related arthritis were excluded. Each patient was examined after at least a 2-year follow-up period after the first visit to establish whether uveitis had occurred. RESULTS: A total of 281 patients with a median disease duration of 3.8 years were included. 191 patients (68%) were treated with MTX. During the observation period, 64 patients (22.8%) developed uveitis, a median of 1.6 year after disease onset. The frequency of uveitis was lower in MTX-treated than in MTX-untreated patients (11.5% vs. 46.7%, respectively, OR=6.7 (95%CI:3.7-12.3), p=0.0000001). Survival analysis confirmed that patients treated with MTX had a lower probability of developing uveitis (HR=4.35, p=0.000001). In subgroup analysis it was shown that MTX was more preventive in boys than in girls, and in patients with JIA onset age of over 5 years compared to those with disease onset less than 5 years. The data of survival analysis of MTX prevention has shown that benefits do not depend on the number of active joints and ANA status. CONCLUSIONS: MTX therapy may prevent the onset of uveitis in children with JIA. Further randomised controlled trials are required to confirm our results.

Using HScore for Evaluation of Hemophagocytosis in Multisystem Inflammatory Syndrome Associated with COVID-19 in Children.

Hemophagocytic syndrome is a key point in the pathogenesis of severe forms of multisystem inflammatory syndrome associated with COVID-19 in children (MIS-C). The factors associated with hemophagocytosis in patients with MIS-C were assessed in the present study of 94 boys and 64 girls ranging in age from 4 months to 17 years, each of whose HScore was calculated. In accordance with a previous analysis, patients with HScore ≤ 91 (n = 79) and HScore > 91 (n = 79) were compared. Patients with HScore > 91 had a higher frequency of symptoms such as cervical lymphadenopathy, dry cracked lips, bright mucous, erythema/swelling of hands and feet, peeling of fingers, edematous syndrome, hepatomegaly, splenomegaly, and hypotension/shock. They also had a higher erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and D-dimer levels, and a tendency to anemia, thrombocytopenia, and hypofibrinogenemia. They more often needed acetylsalicylic acid and biological treatment and were admitted to ICU in 70.9% of cases. Conclusion: The following signs of severe MIS-C were associated with HScore > 91: myocardial involvement, pericarditis, hypotension/shock, and ICU admission.

Determination of Risk Factors for Severe Life-Threatening Course of Multisystem Inflammatory Syndrome Associated with COVID-19 in Children.

Multisystem inflammatory syndrome associated with COVID-19 in children (MIS-C) is a life-threatening condition that often requires intensive care unit (ICU) admission. The aim of this study was to determine risk factors for severe/life-threatening course of MIS-C. The study included 166 patients (99 boys, 67 girls) aged 4 months-17 years (median 8.2 years). The criterion of severity was the fact of ICU admission. To conduct a comparative analysis, MIS-C patients were divided into two groups: patients hospitalized in the ICU (n = 84, 50.6%) and those who did not need ICU admission (n = 82, 49.4%). Patients with a more severe course of MIS-C were significantly older. They had a higher frequency of signs such as rash, swelling, hepatomegaly, splenomegaly, and neurological and respiratory symptoms. Hypotension/shock and myocardial involvement were much more common in patients with severe MIS-C. These patients had a more significant increase in CRP, creatinine, troponin, and D-dimer levels. Additionally, the presence of macrophage activation syndrome was higher in patients admitted to the ICU. Conclusion: Nineteen predictors of severe course of MIS-C were found, out of which hepatomegaly, splenomegaly, D-dimer > 2568 ng/mL, troponin > 10 pg/mL were mainly associated with the probability of being classified as early predictors of severe MIS-C requiring ICU admission.

COVID-19 Associated Vasculitis Confirmed by the Tissues RT-PCR: A Case Series Report.

BACKGROUND: Several cases of skin and central nervous system vasculopathy associated with COVID-19 in children have been published, but the information is rather limited. Our study aimed to describe these cases of vasculitis associated with COVID-19 in children. METHODS: In the retrospective-prospective case series study we included information regarding four children with COVID-19-associated vasculitis. In every case, we had a morphological description and the etiology was confirmed via real-time polymerase chain reaction during a tissue biopsy. RESULTS: The most involved systems were skin (4/4), respiratory (3/4), cardiovascular (2/4), nervous (1/4), eye (1/4), kidney (1/4), and inner year (1/4). All patients had increased inflammatory markers and thrombotic parameters (D-dimer). No patient met the criteria for multisystem inflammatory syndrome in children. Two patients met polyarteritis nodosa criteria, one met Henoch-Schonlein purpura criteria, and one met unclassified vasculitis criteria. All patients were treated with systemic glucocorticosteroids (two-pulse therapy). Non-biologic DMARDs were prescribed in all cases; 1/4 patients (25%) was treated with intravenous immunoglobuline, and 3/4 (75%) were treated with biologics (etanercept, tocilizumab, and adalimumab). CONCLUSIONS: Vasculitis associated with COVID-19 could be a life-threatening condition; SARS-CoV-2 might be a new trigger or etiological agent for vasculitis and other immune-mediated diseases. Further research and collection of similar cases are required.

Simultaneous Characterization of Wildfire Smoke and Surface Properties With Imaging Spectroscopy During the FIREX-AQ Field Campaign.

We introduce and evaluate an approach for the simultaneous retrieval of aerosol and surface properties from Airborne Visible/Infrared Imaging Spectrometer Classic (AVIRIS-C) data collected during wildfires. The joint National Aeronautics and Space Administration (NASA) National Oceanic and Atmospheric Administration Fire Influence on Regional to Global Environments and Air Quality field campaign took place in August 2019, and involved two aircraft and coordinated ground-based observations. The AVIRIS-C instrument acquired data from onboard NASA's high altitude ER-2 research aircraft, coincident in space and time with aerosol observations obtained from the Aerosol Robotic Network (AERONET) DRAGON mobile platform in the smoke plume downwind of the Williams Flats Fire in northern Washington in August 2019. Observations in this smoke plume were used to assess the capacity of optimal-estimation based retrievals to simultaneously estimate aerosol optical depth (AOD) and surface reflectance from Visible Shortwave Infrared (VSWIR) imaging spectroscopy. Radiative transfer modeling of the sensitivities in spectral information collected over smoke reveal the potential capacity of high spectral resolution retrievals to distinguish between sulfate and smoke aerosol models, as well as sensitivity to the aerosol size distribution. Comparison with ground-based AERONET observations demonstrates that AVIRIS-C retrievals of AOD compare favorably with direct sun AOD measurements. Our analyses suggest that spectral information collected from the full VSWIR spectral interval, not just the shortest wavelengths, enables accurate retrievals. We use this approach to continuously map both aerosols and surface reflectance at high spatial resolution across heterogeneous terrain, even under relatively high AOD conditions associated with wildfire smoke.

Standard and increased canakinumab dosing to quiet macrophage activation syndrome in children with systemic juvenile idiopathic arthritis.

Objective: Macrophage activation syndrome (MAS) is a life-threatening, potentially fatal condition associated with systemic juvenile idiopathic arthritis (sJIA). Interleukin-1 (IL-1) is a key cytokine in the pathogenesis of sJIA MAS. Many cases of MAS are medically refractory to traditional doses of biologic cytokine inhibitors and may require increased dosing. When MAS occurs in the setting of sJIA treated with the IL-1 receptor antagonist (IL-1Ra), anakinra, increased anakinra dosing may be beneficial. Increased dosing of another IL-1 inhibitor, canakinumab, a monoclonal antibody to IL-1ß, has not been reported to treat refractory MAS in the setting of sJIA. Methods: Retrospective data collection extracted from the electronic medical record focused on canakinumab usage and dosing in 8 children with sJIA who developed MAS at a single academic center from 2011 to 2020. Results: Eight sJIA children (five girls) with median age 8.5 years (range, 0.9-14.2 years) were included in the present study. Five children developed MAS at disease onset and three during ongoing canakinumab therapy. MAS resolved in all eight children with canakinumab treatment. When the canakinumab dosing was insufficient or MAS developed during canakinumab therapy, the dosing was temporally up-titrated (four patients, maximum 300 mg per dose) without observed side effects. Conclusion: This report provides evidence for the efficacy and safety of short-term increased doses (2-3-times normal) of canakinumab in treating sJIA associated MAS. Further study of the efficacy and safety of increased doses of canakinumab for treatment of MAS in children with sJIA is warranted.

Uveitis Is a Risk Factor for Juvenile Idiopathic Arthritis' Significant Flare in Patients Treated With Biologics.

Objectives: Uveitis is the most frequent extra-articular manifestation of juvenile idiopathic arthritis (JIA). Our study is aimed to evaluate the possible difference in arthritis course depending on uveitis presence in patients with JIA, treated with biologics. Methods: From our database of patients with JIA treated with biologics, we extracted patients to whom the first agent was administrated with or without MTX. The exclusion criteria included treatment with current systemic corticosteroids, infliximab, rituximab, observation period <3 years, and no missing data. After selection, 175 patients were eligible for analysis. We evaluated clinically significant flare with joint involvement (which required change of biologic or non-biologic DMARD) and time to flare. We compared two groups: (i) patients with uveitis (n = 32) and (ii) patients without uveitis (n = 143). For statistical analysis, we used Cox's regression models, the log-Rank test, x 2 test, and the Mann-Whitney test. Results: There was no difference in gender distribution and achievement of arthritis remission between groups. Patients in the non-uveitis group predominantly received etanercept (64.3%). In the uveitis group, the most prescribed biologic agent was adalimumab (71.9%). The presence of uveitis increased the risk of JIA flare, OR = 3.8 (95% CI: 1.7; 8.7), and the cumulative probability of joint flare, RR = 4.5 (95% CI: 1.7; 12.1), p =.003, after adjustment on methotrexate, RR = 3.1 (1.6; 6.), p =.0008. In the subgroup of patients treated with adalimumab, the absence of methotrexate increased the cumulative probability of flare [RR = 6.5 (95% CI: 1.4; 31.1), p = 0.02]. Conclusion: The presence of uveitis proved to be a risk factor in JIA flare. Methotrexate can decrease the cumulative flare probability. Further trials are required.

The Safety and Efficacy of Tofacitinib in 24 Cases of Pediatric Rheumatic Diseases: Single Centre Experience.

JAK-inhibitors are small molecules blocking the JAK-STAT pathway that have proven effective in the treatment of different immune-mediated diseases in adults and juvenile idiopathic arthritis (JIA). AIM OF STUDY: To evaluate the safety and efficacy of tofacitinib in children with different rheumatic diseases. MATERIAL AND METHODS: We extracted information from 24 children with the following diagnosis: JIA (n = 15), undifferentiated systemic autoinflammatory diseases (SAIDs) (n = 7), and juvenile dermatomyositis (JDM) (n = 2) who have been treated with tofacitinib for a period of longer than 6 months. The treatment outcomes were classified according to the opinion of the attending physicians as having a complete response (CR), i.e., the absence of disease activity, or a partial response (PR)-a significant improvement of symptoms and disease activity, or no response (NR)-no changes in disease activity. RESULTS: CR was achieved in 10/24 patients; 7/15 among JIA patients, 1/2 among JDM patients, 4/7 among SAID patients, and PR in 5/15 of JIA, 1/2 of JDM, and 3/7 of SAID patients. Three non-responders with JIA discontinued tofacitinib. Corticosteroids were successfully tapered off in 11/14 patients and discontinued in 2/14 patients. Four patients had side effects not requiring treatment discontinuation: liver enzyme elevation (n = 2), hypercholesterolemia (n = 1), lymphadenitis (n = 1). CONCLUSION: JAK-inhibitors are effective new therapies for the treatment of multiple immune-mediated diseases. Our experience has shown the best results in patients with JIA and JIA-associated alopecia, and type I interferonopathies. More data from randomized controlled clinical trials are needed to use JAK-inhibitors safely in pediatric rheumatic diseases.

Heart Involvement in Multisystem Inflammatory Syndrome, Associated With COVID-19 in Children: The Retrospective Multicenter Cohort Data.

Objectives: Heart involvement in multisystem inflammatory syndrome associated with COVID-19 in children (MIS-C) is a new challenging problem, requiring fast and reliable diagnostics and appropriate treatment. The aim of this study is to describe heart involvement in patients with MIS-C. Study Design: In this retrospective, multicenter cohort study, data of 122 patients were included. All patients met WHO and CDC criteria of MIS-C. Results: Various types of heart involvement in MIS-C patients were observed. Patients with solely coronary artery lesions (CAL, n = 10, 8.2%) had typical features of Kawasaki disease: younger age, thrombocytosis and normal ferritin level, without giant CA aneurysms, thrombosis, myocardial infarction, shock, and ICU admission. Patients with solely myocardial involvement (MI, n = 30, 24.6%) had an older onset age, elevated ferritin, LDH, the highest D-dimer, H score, and thrombocytopenia level. The following clinical signs were associated with MI: gastrointestinal and central nervous system disorder, sore throat, swelling face, splenomegaly, shock, and treatment in the intensive care unit required. Patients with a combination of CAL and MI (n = 10, 8.2%) had symptoms similar to patients with solely MI, except for impressive thrombocytopenia. Shock and ICU admission were found in 34.7% of patients without heart involvement (n = 72, 59%). One major criterion [troponin > 32 pg/ml (52 points)] or at least two minor criteria [face swelling (32 points) and D-Dimer > 1,300 ng/ml (29 points)] were associated with MI (>32 points) with a sensitivity of 67.5% and a specificity of 88.9%. Conclusion: The above-suggested criteria can be added to routine diagnostic procedures to confirm MI in MIS-C patients.

Effects of COVID-19 lockdowns on fine particulate matter concentrations.

Lockdowns during the COVID-19 pandemic provide an unprecedented opportunity to examine the effects of human activity on air quality. The effects on fine particulate matter (PM2.5) are of particular interest, as PM2.5 is the leading environmental risk factor for mortality globally. We map global PM2.5 concentrations for January to April 2020 with a focus on China, Europe, and North America using a combination of satellite data, simulation, and ground-based observations. We examine PM2.5 concentrations during lockdown periods in 2020 compared to the same periods in 2018 to 2019. We find changes in population-weighted mean PM2.5 concentrations during the lockdowns of -11 to -15 µg/m3 across China, +1 to -2 µg/m3 across Europe, and 0 to -2 µg/m3 across North America. We explain these changes through a combination of meteorology and emission reductions, mostly due to transportation. This work demonstrates regional differences in the sensitivity of PM2.5 to emission sources.

Distinguishing Between Multisystem Inflammatory Syndrome, Associated With COVID-19 in Children and the Kawasaki Disease: Development of Preliminary Criteria Based on the Data of the Retrospective Multicenter Cohort Study.

Objectives: Diagnostic between multisystem inflammatory syndrome associated with COVID-19 in children (MIS-C) and Kawasaki disease (KD) can make difficulties due to many similarities. Our study aimed to create a Kawasaki/MIS-C differentiation score (KMDscore) allowing discrimination of MIS-C and KD. Study design: The retrospective multicenter cohort study included clinical, laboratory, and instrumental information about MIS-C (n = 72) and KD (n = 147). The variables allowed to discriminate both conditions used to construct and validate the diagnostic score called the KMDscore. Results: Patients with MIS-C were older, had earlier admission to the hospital, had a shorter time before fever resolution, two times frequently had signs of GI and CNS involvement observed, and had more impressive thrombocytopenia, higher level of CRP, ferritin, ALT, AST, LDH, creatinine, triglycerides, troponin, and D-dimer compared to KD patients. Respiratory signs in MIS-C were presented with pleuritis, acute respiratory distress syndrome, oxygen dependency, lung infiltration, and ground-glass opacities in CT. The heart involvement with fast progression of myocarditis provided the severity of MIS-C and ICU admission due to 12 times higher arterial hypotension or shock and required cardiotonic. No differences in the frequency of CA lesions were seen in the majority of cases. Five criteria, CRP >11 mg/dl (18 points), D-dimer >607 ng/ml (27 points), age >5 years (30 points), thrombocytopenia (25 points), and GI involvement (28 points), were included in the KMDscore. The summa >55 points allowed to discriminate MIS-C from KD with a sensitivity of 87.5% and specificity of 89.1%. Conclusion: The KMDscore can be used to differentiate the diagnostic of MIS-C from KD.

Identification of the best cutoff points and clinical signs specific for early recognition of macrophage activation syndrome in active systemic juvenile idiopathic arthritis.

OBJECTIVES: The purpose of our study was to detect early clinical and laboratory signs that help to discriminate macrophage activation syndrome (MAS) from active systemic juvenile idiopathic arthritis (SJIA) without MAS. METHODS: Our retrospective study was based on reviewing the medical charts of the children admitted to the rheumatology department with active SJIA and definite MAS (n = 18) and without MAS (n = 40). We evaluated the data related to SJIA and MAS at the moment of the patient׳s admission. If the patient had signs of MAS since admission or developed definite MAS later during this flare, he was referred to the main group. The children who did not have MAS during the flare episode and did not have MAS in the past medical history were in the control group. We calculated the cutoff points for MAS parameters, performed the analysis of sensitivity and specificity, identified the predictors, and provided the preliminary diagnostic rule through "the-number-of-criteria-present" approach. RESULTS: The clinical signs were relevant to MAS in SJIA: oligoarticular disease course (OR = 5.6), splenomegaly (OR = 67.6), hemorrhages (OR = 33.0), and respiratory failure (OR = 11.3). The involvement of wrist (OR = 0.2), MCP (OR = 0.1), and PIP joints (OR = 0.1) was protective against MAS development. The best cutoffs for laboratory parameters were PLT ≤ 211 × 10(9)/l, WBC ≤ 9.9 × 10(9)/l, AST > 59.7U/l, LDH > 882U/l, albumin ≤ 2.9g/dl, ferritin > 400µg/l, fibrinogen ≤ 1.8g/l, and proteinuria. The laboratory variables were more precise in the discrimination of early MAS than clinical: any 3 or more laboratory criteria provided the highest specificity (1.0) and sensitivity (1.0) and OR = 2997. CONCLUSIONS: We detected clinical and laboratory markers and created preliminary diagnostic (laboratory) guidelines for early discrimination of MAS in active SJIA.

Successful treatment with tocilizumab every 4 weeks of a low disease activity group who achieve a drug-free remission in patients with systemic-onset juvenile idiopathic arthritis.

BACKGROUND: Systemic juvenile idiopathic arthritis (SoJIA) is the most striking form of juvenile idiopathic arthritis. The aim of our study was to evaluate the clinical responses and outcomes of children with SoJIA to IL-6 blockade using two different tocilizumab (TCZ) treatment protocols designed for milder and more severe SoJIA patient groups, and evaluate the possibility of achieving biologic-free remission. METHODS: Thirty-seven active SoJIA children who have failed treatment with corticosteroids and other DMARDs were included in our retrospective study. TCZ doses were prescribed in two treatment approaches: every 2 weeks TCZ dosing (Q2W) and every 4 weeks TCZ dosing (Q4W). The patients were assigned to these two groups by the study physicians depending on the severity of the SoJIA disease as judged by each clinician. RESULTS: Thirty-three of the 37 children successfully completed the trial. TCZ was discontinued in 11patients during the trial. Seven children achieved inactive disease and were allowed to stop the TCZ and 4 had severe adverse events requiring drug cessation. Currently 7 patients continue to have TCZ-free remission [4/7 remission off-medication, 3/7still on methotrexate (MTX)]. This mixed group had a median treatment duration of 1002 days. The children in remission off of all medications, TCZ and MTX, had a median remission duration of 1162 days (ranged 932-1301 days). Compared to the patients assigned to the Q2W TCZ treatment group, the patients assigned to the Q4W TCZ group had a milder SoJIA course. The patients had higher levels of hemoglobin, total proteins, and serum albumins. They had lower white blood cell counts (WBC), % granulocytes, CRP, ESR, ferritins, and LDH. These children had a lower frequency of internal organ involvement, fewer relapses during TCZ treatment, and no macrophage activation syndrome episodes. CONCLUSIONS: Our experience with TCZ for SoJIA supports the excellent result of other studies. What may be novel is our finding that thisIL-6 blockade with TCZ may be able to be utilized at a less frequent dosing schedule in mild SoJIA compared to severe SoJIA. We discuss other factors that may increase the probability of a patient reaching TCZ-free remission.