sNFL applicability as additional monitoring tool in natalizumab extended interval dosing regimen for RRMS patients.

INTRODUCTION: Extended interval dosing (EID) of Natalizumab (NAT) has been proposed to reduce progressive multifocal leukoencephalopathy (PML) risk associated with standard interval dosing (SID) in people with multiple sclerosis (MS). Previous studies have suggested that NAT effectiveness is maintained in the great majority of patients who switch from SID to EID; monitoring of disease activity is currently based exclusively on clinical and MRI parameters. Frequent MRI are expensive and not always applicable, underlining the need for biological markers able to detect central nervous system lesions. Serum Neurofilament-light chain (sNFL) currently represents the most promising biomarker of disease activity, prognosis and treatment response in MS, and their clinical suitability is increasingly evident. The objective of the present study is to assess the applicability of sNFL as additional/alternative measure of treatment efficacy during EID regimen. METHODS: We measured sNFL by Simoa technology in longitudinal samples from 63 Relapsing Remitting (RR) MS patients switched from SID to EID. INCLUSION CRITERIA: diagnosis of RRMS, age 18-60 years; NAT SID for at least 12 months; NEDA-3 (no evidence of disease activity) for at least 12 months; availability of at least 2 serum samples collected 6 months apart. Patients' follow-up time during EID was at least 12 months and 2 blood samples were collected after at least 6 and 12 months. Clinical examination was performed before each infusion, while MRI 6 and 12 months after NAT initiation and according to PML risk during the whole study. RESULTS: No patients showed clinical or MRI activity during the whole follow-up. sNFL levels measured during SID and EID were comparable, without significant difference between groups. The effect of EID on NFL levels did not show significant effects (LMM, p> 0.05) and sNFL levels did not vary with time during SID or EID protocols (LMM, p> 0.05). Intra-individual sNFL levels demonstrated overall stability during SID and EID (median CV=11% between SID and EID samples). According to our previously published reference values, sNFL levels were in the normal range in all samples, both during SID and EID. CONCLUSIONS: Our results suggest that sNFL quantification can be used as an alternative/additional approach to MRI in managing individual patients. The present work provides a new clinical application of sNFL to monitor NAT efficacy.

Serum neurofilament light chain levels in healthy individuals: A proposal of cut-off values for use in multiple sclerosis clinical practice.

BACKGROUND: Serum Neurofilament Light (sNFL) is the most promising marker for patient's monitoring in Multiple Sclerosis (MS). However, operating reference values for use in clinical practice are still lacking. Here, we defined sNFL reference cut-off values in a cohort of healthy controls (HC) and assessed their performance in Multiple Sclerosis (MS) patients, as well as the intra-individual sNFL variability. METHODS: We measured sNFL by single molecule array (Simoa) assay in 79 HC assessing their correlation with age. Changes of sNFL levels were evaluated during a short-term follow-up (median 67 days between consecutive samples) in a subgroup of 27 participants. sNFL were tested in 23 untreated MS patients, at both diagnostic time and start of therapy (median 80 days after), considering disease activity. RESULTS: Findings confirmed a correlation between sNFL levels and age in HC, thus cut-off values specific for age decades were calculated. sNFL did not vary significantly with time during short-term follow-up (median CV 13%). sNFL levels in MS patients were higher and demonstrated a higher variability between diagnostic time and treatment start (median CV 39%). According to cut-off values, "pathologic" sNFL levels were found in 57% of MS patients at diagnostic time, and in 30% of samples at treatment start. In particular, "pathologic" sNFL levels were found in 80% of samples (16/20) obtained during a phase of disease activity, while a total of 85% of samples (22/26) associated with inactive disease showed sNFL in the normal range. CONCLUSION: This study demonstrates an overall intra-individual stability of sNFL values in the short-term in HC and suggests age-dependent reference cut-off values that could be beneficial for sNFL implementation in clinical practice.

A prediction rule for polyarticular extension in oligoarticular-onset juvenile idiopathic arthritis.

OBJECTIVES: To search for predictors of polyarticular extension in children with oligoarticular-onset juvenile idiopathic arthritis (JIA) and to develop a prediction model for an extended course. METHODS: The clinical charts of consecutive patients with oligoarticular-onset JIA and ≥2 years of disease duration were reviewed. Predictor variables included demographic data, number and type of affected joints, presence of iridocyclitis, laboratory tests including antinuclear antibodies, and therapeutic interventions in the first 6 months. Joint examinations were evaluated to establish whether after the first 6 months of disease patients had persistent or extended course (i.e. involvement of 4 or less, or 5 or more joints). Statistics included univariable and multivariable analyses. Regression coefficients (ß) of variables that entered the best-fitting logistic regression model were converted and summed to obtain a "prediction score" for an extended course. RESULTS: A total of 480 patients with a median disease duration of 7.4 years were included. 61.2% had persistent oligoarthritis, whereas 38.8% experienced polyarticular extension. On multivariable analysis, independent correlations with extended course were identified for the presence of ≥2 involved joints and a CRP >0.8 mg/dl in the first 6 months. The prediction score ranged from 0 to 6 and its cut-off that discriminated best between patients who had or did not have polyarticular extension was >1. Sensitivity and specificity were 59.6 and 79.8, respectively. CONCLUSIONS: The number of affected joints and the CRP level in the first 6 months were the strongest predictors of polyarticular extension in our children with oligoarticular-onset JIA.

Determinants of Discordance Between Criteria for Inactive Disease and Low Disease Activity in Juvenile Idiopathic Arthritis.

OBJECTIVE: To assess concordance among criteria for inactive disease (ID) and low disease activity (LDA) in juvenile idiopathic arthritis (JIA) and to seek factors driving discordance. METHODS: The frequency of fulfillment of existing criteria was evaluated in information on 10,186 patients extracted from 3 cross-sectional data sets. Patients were divided up according to the functional phenotypes of oligoarthritis and polyarthritis. Concordance between criteria was examined using weighted Venn diagrams. The role of each individual component in explaining discordance between criteria was assessed by calculating the absolute number and percentage of instances in which the component was responsible for discrepancy between definitions. RESULTS: Criteria for ID were met by 28.6-41.1% of patients with oligoarthritis and by 24.0-33.4% of patients with polyarthritis. Criteria for LDA were met by 44.8-62.4% of patients with oligoarthritis and by 44.6-50.4% of patients with polyarthritis. There was a 57.9-62.3% overlap between criteria for ID and a 67.9-85% overlap between criteria for LDA. Parent and physician global assessments and acute-phase reactants were responsible for the majority of instances of discordance among criteria for ID (8.7-15.5%, 10.0-12.3%, and 10.8-17.3%, respectively). CONCLUSION: We found fair concordance between criteria for ID and LDA in JIA, with the main drivers of discordance for ID being physician and parent global assessments and acute-phase reactants. This observation highlights the need for further studies aimed to evaluate the impact of subjective physician and parent perception of disease remission and of laboratory measures of inflammatory activity on the definition of ID.

Analysis of arthritis flares after achievement of inactive disease with methotrexate monotherapy in juvenile idiopathic arthritis.

OBJECTIVES: To investigate the frequency of arthritis flare and factors affecting occurrence of flare in children with juvenile idiopathic arthritis (JIA) who achieved inactive disease (ID) with methotrexate (MTX) monotherapy. METHODS: A total of 217 patients were included. The modality of treatment discontinuation, time of MTX withdrawal, and disease course were examined retrospectively. For each patient, the first episode of ID after MTX start was evaluated. Patient follow-up was censored at occurrence of flare or at last visit with persistent ID. RESULTS: 170 patients (78.3%) had arthritis flare after a median of 1.6 years, whereas 47 (21.7%) maintained ID until last visit, after a median of 3 years. 54.2% of patients had discontinued MTX after ID, whereas 45.8% were still receiving MTX at the time of study censoring. Among patients who had MTX withdrawn, the median interval between ID and MTX stop was 1.5 years. Occurrence of flare was more common in patients who were still receiving MTX at study censoring than in those who had discontinued MTX (p<0.001). Most patients (78.8%) had MTX tapered over time by increasing the interval between doses. Tapering modality was comparable between patients with flare and persistent ID. Only 7.7% of the patients had a biologic DMARD started at the time of flare. CONCLUSIONS: Our results confirm that children with JIA who achieve ID with MTX monotherapy have a high risk of arthritis flare. The risk of flare was independent of withdrawal strategy. Most flare episodes were not treated with biologic therapy.

Thalidomide as treatment of crohn-like disease occurred after allogeneic hematopoietic stem cell transplantation in a pediatric patient.

BACKGROUND: Autoimmune diseases may occur after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and inflammatory bowel disease (IBD or Crohn disease) is rarely described. We describe a child who developed CD after allo-HSCT, successfully treated with thalidomide. CASE REPORT: A child affected by mucopolysaccharidosis type I received two allogeneic HSCTs for rejection after the first one. After cutaneous and intestinal chronic GvHD and 6 months after HSCT, the patients developed a trilinear autoimmune cytopenia successfully treated with rituximab and sirolimus. Due to persisting intestinal symptoms, colonoscopies were performed and histological findings demonstrated a picture of CD. Based on this observation and according to the recommendations for the treatment of CD, thalidomide was started. A complete stable clinical response was obtained 8 weeks after start of thalidomide. Colonoscopy performed 4.8 years later demonstrated a complete endoscopic and histological remission of CD. DISCUSSION: In this case, the diagnosis of CD after HSCT was based on histological findings. Indeed, repeated colonscopies were necessary for diagnosis, since both clinical and endoscopic features are often common to chronic GvHD and CD. Thalidomide was started at the dose of 1.7 mg/Kg/day, and it was well tolerated. Mild peripheral neurotoxicity occurred 5 years later but disappeared completely with the dose reduction. Currently, the patient is in complete remission from CD, despite the discontinuation of all the immunosuppressive therapies. CONCLUSIONS: Thalidomide could represent a therapeutic option to treat CD as autoimmune disease after allogeneic HSCT.

Rituximab Unveils Hypogammaglobulinemia and Immunodeficiency in Children with Autoimmune Cytopenia.

BACKGROUND: Rituximab (RTX; anti-CD20 mAb) is a treatment option in children with refractory immune thrombocytopenia, autoimmune hemolytic anemia (AHA), and Evans syndrome (ES). Prevalence and clinical course of RTX-induced hypogammaglobulinemia in these patients are poorly known. OBJECTIVE: To evaluate the prevalence and risk factors for persistent hypogammaglobulinemia (PH) after RTX use. METHODS: Clinical and immunologic data from children treated with RTX for immune thrombocytopenia, AHA, and ES were collected from 16 Italian centers and 1 UK center at pre-RTX time point (0), +6 months, and yearly, up to 4 years post-RTX. Patients with previously diagnosed malignancy or primary immune deficiency (PID) were excluded. RESULTS: We analyzed 53 children treated with RTX for immune thrombocytopenia (n = 36), AHA (n = 13), and ES (n = 4). Median follow-up was 30 months (range, 12-48). Thirty-two percent of patients (17 of 53) experienced PH, defined as IgG levels less than 2 SD for age at last follow-up (>12 months after RTX). Significantly delayed B-cell recovery was observed in children experiencing PH (hazard ratio, 0.55; P < .05), and 6 of 17 (35%) patients had unresolved B-cell lymphopenia at last follow-up. PH was associated with IgA and IgM deficiency, younger age at RTX use (51 vs 116 months; P < .01), a diagnosis of AHA/ES, and better response to RTX. Nine patients with PH (9 of 17 [53%]) were eventually diagnosed with a PID. CONCLUSIONS: Post-RTX PH is a frequent condition in children with autoimmune cytopenia; a sizable proportion of patients with post-RTX PH were eventually diagnosed with a PID. In-depth investigation for PID is therefore recommended in these patients.

A prediction rule for lack of achievement of inactive disease with methotrexate as the sole disease-modifying antirheumatic therapy in juvenile idiopathic arthritis.

BACKGROUND: To investigate the frequency of achievement of inactive disease (ID) in children with juvenile idiopathic arthritis (JIA) treated with methotrexate (MTX) as the sole disease-modifyng antirheumatic (DMARD) therapy and to develop a prediction model for lack of attainment of ID. METHODS: The clinical charts of consecutive patients started with MTX as the sole DMARD between 2000 and 2013 were reviewed. Patient follow-up was censored at first episode of ID or, in case ID was not reached, at last follow-up visit or when a biologic DMARD was prescribed. The characteristic at MTX start of patients who achieved or did not achieve ID were compared with univariate and multivariable analyses. Regression coefficients (ß) of variables that entered the best-fitting logistic regression model were converted and summed to obtain a "prediction score" for lack of achievement of ID. RESULTS: A total of 375 patients were included in the study. During MTX administration, 8.8% were given systemic corticosteroids and 44.1% intra-articular corticosteroids. After MTX start, 229 (61%) patients achieved ID after a median of 1.7 years, whereas 146 patients (39%) did not reach ID after a median of 1.2 years. On multivariable analysis, independent correlations with lack of achievement of ID were identified for the disease categories of systemic arthritis, enthesitis-related arthritis (ERA) and polyarthritis and C-reactive protein (CRP) >  1.4 mg/dl. The prediction score ranged from 0 to 3 and its cutoff that discriminated best between patients who achieved or did not achieve ID was > 0.5. The categories of systemic arthritis or ERA, both of which had a score greater than 0.5, were sufficient alone to predict a lower likelihood to reach ID. Polyarthritis and increased CRP, whose score was 0.5, assumed a predictive value only when present in association. CONCLUSION: A conventional treatment regimen based on MTX as the sole DMARD led to achievement of ID in a sizeable proportion of children with JIA. Our findings help to outline the characteristics of patients who may deserve a synthetic DMARD other than MTX or the introduction of a biologic DMARD from disease outset.