Serum interleukin-18 levels can improve the diagnostic performance of the PRINTO and ILAR criteria for systemic juvenile idiopathic arthritis.

OBJECTIVE: Recently, the Pediatric Rheumatology International Trials Organization (PRINTO) has proposed revisions to the current International League of Associations for Rheumatology (ILAR) criteria for systemic juvenile idiopathic arthritis (s-JIA). Interleukin (IL)-18 overproduction plays a significant role in the pathogenesis of s-JIA. This study aimed to evaluate the performance of the PRINTO criteria compared with the ILAR criteria and determine whether serum IL-18 levels improve their diagnostic performances. METHODS: Overall, 90 patients with s-JIA and 27 patients with other febrile disease controls presenting with a prolonged fever of > 14 days and arthritis and/or erythematous rash were enrolled. The ILAR and PRINTO classification criteria were applied to all patients and examined with expert diagnoses. Enzyme-linked immunosorbent assay was used for measuring serum IL-18 levels. RESULTS: The PRINTO criteria had higher sensitivity but lower specificity than the ILAR criteria (sensitivity: PRINTO 0.856, ILAR 0.533; specificity: PRINTO 0.259, ILAR 0.851). With the addition of serum IL-18 levels ≥ 4,800 pg/mL, the sensitivity of the ILAR criteria and specificity of the PRINTO criteria were improved to 1.000 and 1.000, respectively. PRINTO plus serum IL-18 levels ≥ 4,800 pg/mL showed the highest value in Youden's index (sensitivity - [1 - specificity]). CONCLUSION: Serum IL-18 levels could improve the diagnostic performance of the PRINTO and ILAR criteria for s-JIA. The PRINTO criteria plus serum IL-18 levels ≥ 4,800 pg/mL could be the best diagnostic performance for s-JIA.

Etiology and clinical course of severe and extreme thrombocytosis in children: a retrospective single-center study.

The aim of this study was to describe the etiology and clinical course in children with severe thrombocytosis (ST, platelet counts > 900 × 109/L) and extreme thrombocytosis (ET, platelet counts > 1000 × 109/L) in a tertiary pediatric hospital. Patients aged 0-18 years with platelet counts over 900 × 109/L who were admitted to our hospital were analyzed. Thrombocytosis was defined as a platelet count exceeding 450 × 109/L. Thrombosis was diagnosed based on computed tomography scans or ultrasound findings. Potential factors associated with the development of extreme thrombocytosis were identified using logistic regression models. Only one (0.8%) out of the 120 patients identified with ST (n = 61) and ET (n = 59) had primary thrombocytosis. The most common underlying condition was congenital heart disease (26.7%), followed by Kawasaki disease (16.7%). With the exception of the hemoglobin level, no major differences were found for the baseline characteristics between the ST and ET groups. A lower hemoglobin level (< 10.0 g/dL) at the onset of thrombocytosis was identified as a predictor for ET development (adjusted odds ratio 2.73, 95% confidence interval 1.18-6.28). Overall, 56 of 120 (46.7%) patients received aspirin therapy. Venous thrombosis occurred in one (0.8%) patient. CONCLUSIONS: We found a low proportion of primary thrombocytosis and a low incidence of thrombosis in children with ST and ET. Our results suggest that pediatric ST and ET may share common characteristics and may have features that are distinct from those in adults. WHAT IS KNOWN: • Secondary thrombocytosis is a frequent finding in children. • Adult extreme thrombocytosis has been found to be associated with primary thrombocytosis. WHAT IS NEW: • There were no major differences in the baseline characteristics between children with severe and extreme thrombocytosis. • The incidence of thrombosis was markedly low in both severe and extreme thrombocytosis groups.

The dynamics of laboratory markers reflecting cytokine overproduction in macrophage activation syndrome complicated with systemic juvenile idiopathic arthritis.

OBJECTIVES: To validate the correlation between laboratory markers reflecting disease activity of macrophage activation syndrome (MAS) and serum cytokine levels and identify the valuable laboratory markers that change over time for a prompt MAS diagnosis. METHODS: Serum cytokine levels were determined by enzyme-linked immunosorbent assay and compared with laboratory markers reflecting MAS disease activity.The changes in values were evaluated from the acute phase of systemic juvenile idiopathic arthritis (s-JIA) to MAS diagnosis. RESULTS: CXCL9 was significantly correlated with aspartate aminotransferase (AST), lactate dehydrogenase (LDH), D dimer, and urine ß2 microglobulin levels. sTNF-RII was significantly correlated with platelet counts, AST, LDH, D dimer, and ferritin levels. Significant changes in platelet count, LDH, and D dimer levels were observed. Decreased platelet counts were the most valuable indicator for MAS diagnosis. CONCLUSION: Monitoring the laboratory markers that change over time, particularly decreased platelet counts, was valuable for the prompt MAS diagnosis in s-JIA.

Clinical significance of serum cytokine profiles for differentiating between Kawasaki disease and its mimickers.

OBJECTIVES: To investigate the clinical significance of serum cytokine profiles for differentiating between Kawasaki disease (KD) and its mimickers. METHODS: Patients with KD, including complete KD, KD shock syndrome (KDSS), and KD with macrophage activation syndrome (KD-MAS), and its mimickers, including multisystem inflammatory syndrome in children, toxic shock syndrome, and Yersinia pseudotuberculosis infection, were enrolled. Serum levels of interleukin (IL)-6, soluble tumor necrosis factor receptor type II (sTNF-RII), IL-10, IL-18, and chemokine (C-X-C motif) ligand 9 (CXCL9) were measured using enzyme-linked immunosorbent assay and compared them with clinical manifestations. RESULTS: Serum IL-6, sTNF-RII, and IL-10 levels were significantly elevated in patients with KDSS. Serum IL-18 levels were substantially elevated in patients with KD-MAS. Patients with KD-MAS and KD mimickers had significantly elevated serum CXCL9 levels compared with those with complete KD. Area under the receiver operating characteristic curve analysis showed that serum IL-6 was the most useful for differentiating KDSS from the others, IL-18 and CXCL9 for KD-MAS from complete KD, and CXCL9 for KD mimickers from complete KD and KD-MAS. CONCLUSION: Serum cytokine profiles may be useful for differentiating between KD and its mimickers.

Impact of tracheostomies on the long-term survival of patients with trisomy 13 syndrome.

In this retrospective cohort study, we investigated the impact of tracheostomies on the long-term survival of children with trisomy 13 syndrome at a Japanese tertiary pediatric center. We compared survival and survival to discharge rates between patients who underwent tracheostomies during their NICU stays (T group, n = 8) and those who did not (non-T group, n = 11). A total of 19 patients enrolled. Median survival in all patients was 673 (266-1535) days. Significant differences in the 1-, 2-, and 3-year survival rates were found between the T and the non-T groups (100% vs. 46%, p = 0.018; 88% vs. 18%, p = 0.006; 63% vs. 9%, p = 0.041, respectively). The survival to discharge rate was higher in the T versus non-T group (75% vs. 45%, p = 0.352). This study highlights a significantly higher long-term survival of patients with trisomy 13 syndrome who underwent tracheostomies during their NICU stays.

Epidemiology conduction of paediatric rheumatic diseases based on the registry database of the Pediatric Rheumatology Association of Japan.

OBJECTIVES: Although epidemiological surveys of paediatric rheumatic diseases in Japan have been conducted, they were single surveys with no continuity. This is the first report of the Pediatric Rheumatology Association of Japan registry database, which was established to continuously collect data for paediatric rheumatic diseases. METHODS: Pediatric Rheumatology International Collaborate Unit Registry version 2 (PRICUREv2) is a registry database established by the Pediatric Rheumatology Association of Japan. The registry data were analysed for the age of onset, time to diagnosis, sex differences, seasonality, and other factors. RESULTS: Our data showed the same trend regarding rates of paediatric rheumatic diseases reported in Japan and other countries. The age of onset was lower in juvenile idiopathic arthritis (JIA) and juvenile dermatomyositis and higher in systemic lupus erythematosus and Sjögren's syndrome. The time to diagnosis was relatively short in JIA and systemic lupus erythematosus but longer in juvenile dermatomyositis and Sjögren's syndrome. Rheumatoid factor-positive polyarticular JIA showed a seasonality cluster with regard to onset. CONCLUSION: PRICUREv2 aided the retrieval and evaluation of current epidemiological information on patients with paediatric rheumatic diseases. It is expected that the data collection will be continued and will be useful for expanding research in Japan.

Improving survival in patients with trisomy 18.

The effects of medical and surgical interventions on the survival of patients with trisomy 18 have been reported, leading to changes in perinatal management and decision-making. However, few studies have fully reported the recent changes in survival and treatment of trisomy 18. We examined how treatment and survival of patients with trisomy 18 have changed over a decade in a Japanese pediatric tertiary referral center. This retrospective cohort study included patients with trisomy 18 who were admitted within the first 7 days of life at the Hyogo Prefectural Kobe Children's Hospital between 2008 and 2017. The patients were divided into early period (EP) and late period (LP) groups based on the birth year of 2008-2012 and 2013-2017, respectively. Changes in treatment and survival rates were compared between the two groups. A total of 56 patients were studied (29 in the EP group and 27 in the LP group). One-year survival rates were 34.5% and 59.3% in the EP and LP groups, respectively. The survival to discharge rate significantly increased from 27.6% in the EP group to 81.5% in the LP group (p < 0.001). The proportion of patients receiving surgery, especially for congenital heart defects, significantly increased from 59% in the EP group to 96% in the LP group (p = 0.001). In our single-center study, survival and survival to discharge were significantly improved in patients with trisomy 18, probably because of increased rate of surgical interventions. These findings may facilitate better decision-making by patients' families and healthcare providers.

Comparison of serum cytokine profiles in macrophage activation syndrome complicating different background rheumatic diseases in children.

OBJECTIVES: To compare the cytokines involved in the development of macrophage activation syndrome (MAS) in different background rheumatic diseases and to identify serum biomarkers for MAS diagnosis. METHODS: Serum neopterin, IL-6, IL-18 and soluble TNF receptor (sTNFR) type I (sTNFR-I) and type II (sTNFR-II) levels were determined using ELISA in 12 patients with SLE, including five with MAS; 12 patients with JDM, including four with MAS; 75 patients with Kawasaki disease (KD), including six with MAS; and 179 patients with systemic JIA (s-JIA), including 43 with MAS. These results were compared with the clinical features of MAS. RESULTS: Serum neopterin, IL-18 and sTNFR-II levels were significantly higher during the MAS phase than during the active phase in patients with all diseases. Furthermore, serum sTNFR-I levels were significantly higher during the MAS phase than during the active phase in patients with SLE, KD and s-JIA. Receiver operating characteristic (ROC) curve analysis revealed that serum sTNFR-I levels for SLE, serum IL-18 levels for JDM, and serum sTNFR-II levels for KD and s-JIA had the highest areas under the ROC curve. Serum levels of these cytokines were significantly and positively correlated with serum ferritin levels. CONCLUSIONS: Overproduction of IFN-γ, IL-18 and TNF-α might be closely related to the development of MAS. Serum levels of sTNFR-I for SLE, IL-18 for JDM, and sTNFR-II for KD and s-JIA might be useful diagnostic markers for the transition from active phase to MAS.

Clinical significance of interleukin-18 for the diagnosis and prediction of disease course in systemic juvenile idiopathic arthritis.

OBJECTIVE: To investigate the clinical significance of serum IL-18 levels for the diagnosis of systemic JIA (s-JIA) and to predict the disease course of s-JIA. METHODS: Overall, 116 patients with s-JIA, 151 with other diseases and 20 healthy controls were analysed. Serum IL-18 levels were measured longitudinally in 41 patients with s-JIA from active phase through remission phase. Serum IL-18 levels were quantified via enzyme-linked immunosorbent assay and the results were compared with clinical features and the disease course of s-JIA. RESULTS: The serum IL-18 level cut-off value for differentiation of s-JIA from other diseases was 4800 pg/ml. In patients with a monocyclic course, serum IL-18 levels steadily decreased during the inactive phase and low levels were sustained during remission. In contrast, in patients with a chronic course, elevated serum IL-18 levels were sustained even during the inactive phase. In patients with a polycyclic course, serum IL-18 levels were elevated during disease flares and normalized during the inactive phase. The serum IL-18 level cut-off value for diagnosis of remission in s-JIA was 595 pg/ml. CONCLUSION: Serum IL-18 levels of >4800 pg/ml may be useful for differentiating between s-JIA and other diseases. Monitoring of serum IL-18 levels might be useful for predicting the disease course and assessing remission in s-JIA.

Comparison of serum biomarkers for the diagnosis of macrophage activation syndrome complicating systemic juvenile idiopathic arthritis during tocilizumab therapy.

BACKGROUND: To compare the accuracy of serum biomarkers for the diagnosis of macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (s-JIA) during tocilizumab therapy. METHODS: Serum cytokine levels of neopterin, IL-18, C-X-C motif chemokine ligand 9, soluble tumor necrosis factor receptor (sTNFR)-I, and sTNFR-II were determined by enzyme-linked immunosorbent assay in 36 patients with MAS complicating s-JIA including 12 patients receiving tocilizumab. Furthermore, the serum sTNFR-II/I ratio was compared with the clinical features of MAS. RESULTS: The levels of all serum cytokines at MAS diagnosis were significantly lower in the tocilizumab-treated group than in the tocilizumab-untreated group. In contrast, the serum sTNFR-II/I ratio at MAS diagnosis was comparable between the tocilizumab-treated and the tocilizumab-untreated groups. The receiver operating characteristic curve analysis revealed that the area under the curve and cut-off values of sTNFR-II/I ratio were 0.9722 and 4.71, respectively. The serum sTNFR-II/I ratio, which was significantly elevated in patients with MAS complicating s-JIA, was correlated positively with disease activity. CONCLUSIONS: These findings suggest that the serum sTNFR-II/I ratio might be a useful indicator to evaluate disease activity in MAS complicating s-JIA and a useful diagnostic marker for the transition from active-phase s-JIA to MAS even in tocilizumab-treated patients. IMPACT: This is the first study to analyze the role of tocilizumab in modifying the serum levels of biomarkers used for the diagnosis of MAS complicating s-JIA. We found the biomarker for the diagnosis of MAS complicating s-JIA during tocilizumab therapy. We hope our results might be useful for the development of a new criteria for the diagnosis of MAS complicating s-JIA in patients treated with tocilizumab in future.

Extensive serum biomarker analysis in patients with macrophage activation syndrome associated with systemic lupus erythematosus.

The present study employed an antibody array that simultaneously detects 174 cytokines to identify cytokines involved in the development of macrophage activation syndrome (MAS) associated with systemic lupus erythematosus (SLE) with a view to elucidating potential predictive markers. Eight SLE patients, including four with MAS, were analyzed. Levels of 31 cytokines were significantly elevated in the MAS phase compared with those in the active phase of SLE. Among these cytokines, the MAS/active phase ratios of CXCL9 and soluble tumor necrosis factor receptor II (sTNFR-II) were highest. Elevated serum CXCL9 and sTNFR-II levels during the MAS phase were confirmed by ELISA and were strongly correlated with other inflammatory markers, reflecting the disease activity of MAS associated with SLE. These results highlight the clinical significance of serum CXCL-9 and sTNFR-II levels, and indicate they may be useful biomarkers for the diagnosis of MAS associated with SLE.

Comparison of serum biomarkers for the diagnosis of macrophage activation syndrome complicating systemic juvenile idiopathic arthritis.

Our study aimed to compare the accuracy of serum biomarkers for the diagnosis of macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (s-JIA). Serum cytokine levels (neopterin, IL-18, and CXCL9 and soluble tumor necrosis factor receptor type I (sTNFR-I) and II) were determined by enzyme-linked immunosorbent assay in 78 patients with s-JIA, including 21 with MAS. Receiver operating characteristic curve analysis revealed area under the curve values and cut off values of neopterin, IL-18, CXCL9, sTNFR-II/I ratio and ferritin were 0.9465/19.5 nmol/l, 0.8895/69250 ng/ml, 0.9333/3130 pg/ml, 0.9395/3.796 and 0.8671/2560 ng/ml, respectively. Serum neopterin levels were significantly elevated in patients with MAS and those were correlated positively with disease activity. In conclusion, serum neopterin levels may be used as a promising indicator of disease activity in s-JIA and MAS and for evaluating it. It may also be a useful marker to diagnose the transition to MAS from active-phase s-JIA.

Clinical significance of serum CXCL9 levels as a biomarker for systemic juvenile idiopathic arthritis associated macrophage activation syndrome.

To clarify cytokines involved in the development of systemic juvenile idiopathic arthritis (s-JIA) associated macrophage activation syndrome (MAS) and to identify the serum biomarkers for the diagnosis of s-JIA associated MAS, we employed an antibody array that simultaneously detects 174 cytokines. Fifteen s-JIA patients including 5 patients receiving tocilizumab (TCZ) were analyzed. The levels of five cytokines were significantly elevated in MAS phase compared to those in the active phase of s-JIA. CXCL9 showed the most significant increase following the development of s-JIA associated MAS. Next, to confirm clinical significance of serum CXCL9 levels as a biomarker for s-JIA associated MAS, serum CXCL9 levels in 56 patients with s-JIA including 20 with MAS were analyzed. Results were compared with the clinical features of s-JIA associated MAS. Serum CXCL9 levels correlated positively with disease activity. Monitoring of serum CXCL9 is useful for the evaluation of disease activity in s-JIA associated MAS.

Soluble CD163, a unique biomarker to evaluate the disease activity, exhibits macrophage activation in systemic juvenile idiopathic arthritis.

This study aims to investigate the clinical significance of serum soluble CD163 (sCD163) levels as a predictor of the disease activity of systemic juvenile idiopathic arthritis (s-JIA). In this study, we examined 63 patients with s-JIA, four with Epstein-Barr virus-induced hemophagocytic lymphohistiocytosis (EBV-HLH), and seven with Kawasaki disease (KD), along with 14 healthy controls. We quantified serum cytokine levels (sCD163, neopterin, IL-18, IL-6) by enzyme-linked immunosorbent assay and compared the results with the clinical features of s-JIA. Serum sCD163 levels were significantly elevated in patients with s-JIA associated macrophage activation syndrome (MAS) and EBV-HLH compared to those in patients with acute-phase s-JIA and KD. In addition, serum sCD163 levels profoundly increased with the progress of MAS and correlated positively with the disease activity of s-JIA, even in patients receiving tocilizumab. Furthermore, serum sCD163 levels significantly decreased in the inactive phase compared to those in the active phase and normalized in remission. The correlation between macrophage activation and serum sCD163 levels might be a unique indicator of the disease activity and a potential diagnostic laboratory criterion for clinical remission in patients with s-JIA, including those receiving tocilizumab.

Early prediction for over two years efficacy of the first biologic agent for polyarticular juvenile idiopathic arthritis: A multi-institutional study in Japan.

OBJECTIVE: To estimate target of treatment for long-term efficacy of the first biologic agent used to treat polyarticular juvenile idiopathic arthritis (pJIA). METHODS: A retrospective cohort of patients with pJIA treated at six medical institutions in Japan between 1 March 2005 and 31 October 2014 was identified. The patients were divided by 2-year treatment periods with the first biologic agent into continuous treatment group and switching group. Three markers were examined: matrix metalloproteinase-3 (MMP-3), erythrocyte sedimentation rate (ESR), and disease activity score (DAS) 28-ESR. RESULTS: Thirty-two pJIA patients (8 boys, 24 girls) from 43 recruited patients were included in this study. The treatment periods with the first biologic agent in continuous treatment group (24 patients, 75%) was 40 months (median, range 24-119) and switching group (8 patients; 25%) was 9.5 months (median, 6-18). Markers [odds ratio (95% confidence interval)] at 3 months were MMP-3 [1.02 (0.99-1.05), p = .219], ESR [1.00 (0.78-1.30), p = .998], and DAS28-ESR [13.9 (2.08-409.82), p = .035]. The cut-off point for DAS28-ESR at 3 months to distinguish the two groups was 2.49 (sensitivity, 87.5%; specificity, 87.5%). CONCLUSION: DAS28-ESR of 2.49 at 3 months after initiating the first biologic agent can be a target of sustained treatment in pJIA patients.

Leucine-rich α2-glycoprotein as the acute-phase reactant to detect systemic juvenile idiopathic arthritis disease activity during anti-interleukin-6 blockade therapy: A case series.

OBJECTIVES: To assess the role of leucine-rich α2-glycoprotein (LRG) as a biomarker for monitoring systemic juvenile idiopathic arthritis (s-JIA) disease activity during interleukin (IL)-6 blockade treatment. METHODS: We serially measured serum LRG levels in four s-JIA patients treated with the anti-IL-6 receptor antibody tocilizumab and determined the correlation between clinical symptoms and other inflammatory biomarkers and proinflammatory cytokines, including IL-18, IL-6, neopterin, and tumor necrosis factor-α receptor type I and II. The serum levels of LRG and proinflammatory cytokines were determined using enzyme-linked immunosorbent assay. RESULTS: Serum LRG levels increased concomitantly with s-JIA disease flare-up and macrophage activation syndrome development. Furthermore, even in the clinically inactive phase, serum LRG levels were well above normal values. There were no correlations between serum LRG levels and indicators of s-JIA disease activity other than aspartate aminotransferase. There were significant positive correlations between serum LRG levels and proinflammatory cytokines. CONCLUSIONS: Serum LRG levels might be a unique and potential biomarker of s-JIA disease activity during IL-6 blockade treatment.