The challenge of early diagnosis of autoimmune lymphoproliferative syndrome in children with suspected autoinflammatory/autoimmune disorders.

OBJECTIVES: To test the usefulness of an extended panel of lymphocyte subsets in combination with Oliveira's diagnostic criteria for the identification of autoimmune lymphoproliferative syndrome (ALPS) in children referred to a paediatric rheumatology centre. METHODS: Patients referred from 2015 to 2018 to our rheumatology unit for an autoimmune or autoinflammatory condition were retrospectively analysed. Oliveira's required criteria [chronic lymphoproliferation and elevated double-negative T (DNT)] were applied as first screening. Flow cytometry study included double-negative CD4-CD8-TCRαß+ T lymphocytes (DNT), CD25+CD3+, HLA-DR+CD3+ T cells, B220+ T cells and CD27+ B cells. Data were analysed with a univariate logistic regression analysis, followed by a multivariate analysis. Sensitivity and specificity of the Oliveira's required criteria were calculated. RESULTS: A total of 264 patients were included in the study and classified as: (i) autoimmune diseases (n = 26); (ii) juvenile idiopathic arthritis (JIA) (35); (iii) monogenic systemic autoinflammatory disease (27); (iv) periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome (100); (v) systemic undefined recurrent fever (45); (vi) undetermined-systemic autoinflammatory disease (14); or (vii) ALPS (17). Oliveira's required criteria displayed a sensitivity of 100% and specificity of 79%. When compared with other diseases the TCRαß+B220+ lymphocytes were significantly increased in ALPS patients. The multivariate analysis revealed five clinical/laboratory parameters positively associated to ALPS: splenomegaly, female gender, arthralgia, elevated DNT and TCRαß+B220+ lymphocytes. CONCLUSIONS: Oliveira's required criteria are useful for the early suspicion of ALPS. TCRαß+B220+ lymphocytes should be added in the diagnostic work-up of patients referred to the paediatric rheumatology unit for a suspected autoimmune or autoinflammatory condition, providing a relevant support in the early diagnosis of ALPS.

Clinical Significance of Serum Soluble TNF Receptor I/II Ratio for the Differential Diagnosis of Tumor Necrosis Factor Receptor-Associated Periodic Syndrome From Other Autoinflammatory Diseases.

Objectives: Genetic analysis of TNFRSF1A can confirm the diagnosis of tumor necrosis factor receptor-associated periodic syndrome (TRAPS), but interpretation of the pathogenesis of variants of unknown significance is sometimes required. The aim of this study was to evaluate the clinical significance of serum soluble tumor necrosis factor receptor type I (sTNFR-I)/II ratio to differentiate TRAPS from other autoinflammatory diseases. Methods: Serum sTNFR-I and sTNFR-II levels were measured using an enzyme-linked immunosorbent assay in patients with TRAPS (n = 5), familial Mediterranean fever (FMF) (n = 14), systemic juvenile idiopathic arthritis (s-JIA) (n = 90), and Kawasaki disease (KD) (n = 37) in the active and inactive phase, along with healthy controls (HCs) (n = 18). Results: In the active phase, the serum sTNFR-I/II ratio in patients with s-JIA, KD, and FMF was significantly elevated compared with that in HCs, whereas it was not elevated in patients with TRAPS. In the inactive phase, the serum sTNFR-I/II ratio in patients with s-JIA and FMF was significantly higher compared with that in HCs, and the ratio was lower in TRAPS patients than in patients with s-JIA and FMF. Conclusions: Low serum sTNFR-I/II ratio in the active and inactive phase might be useful for the differential diagnosis of TRAPS and other autoinflammatory diseases.

The use of S100 proteins testing in juvenile idiopathic arthritis and autoinflammatory diseases in a pediatric clinical setting: a retrospective analysis.

BACKGROUND: Serum phagocyte-derived alarmins S100A8/9 and S100A12 are considered useful for the assessment of inflammatory diseases. Our study evaluated the use of S100 proteins in a pediatric clinical setting for estimating disease activity and supporting diagnosis. METHODS: Patients (n = 136) who had S100 proteins tested as part of clinical care were included in this study and relevant information obtained from the medical record: C-reactive protein (CRP), disease activity status (inactive: = 0 joint; active: > 0 active joint), systemic symptoms in systemic JIA (sJIA), and symptoms of flare of other autoinflammatory and fever syndromes. Patients were categorized as: sJIA, non-systemic JIA (nsJIA), other defined autoinflammatory syndromes (AID) and systemic undifferentiated recurring fever syndromes (SURFS). RESULTS: Patients with sJIA (n = 21) had significantly higher levels of S100A8/9 and S100A12 compared to patients with nsJIA (n = 49), other AIDs (n = 8) or SURFS (n = 14) (all p < 0.0001). Compared to CRP [area under the receiver operating characteristics curve (AUC) = 0.7], S100 proteins were superior in differentiating sJIA from AID and SURFS [AUC = 0.9]. S100A8/9 and S100A12 levels were not associated with disease activity in nsJIA, AID or SURFS. S100A8/9 and S100A12 levels were significantly higher in active sJIA compared to inactive (p = 0.0002 and p = 0.0002 respectively). CONCLUSION: Compared to other autoinflammatory and fever syndromes, sJIA patients have markedly higher levels of S100A8/9 and S100A12 proteins which may assist with diagnosis. S100 levels slightly outperformed CRP in distinguishing sJIA from other diagnoses and in sJIA disease activity. S100 proteins may aid in monitoring disease activity in sJIA patients.

TRAP1 chaperone protein mutations and autoinflammation.

We identified a consanguineous kindred, of three affected children with severe autoinflammation, resulting in the death of one sibling and allogeneic stem cell transplantation in the other two. All three were homozygous for MEFV p.S208C mutation; however, their phenotype was more severe than previously reported, prompting consideration of an oligogenic autoinflammation model. Further genetic studies revealed homozygous mutations in TRAP1, encoding the mitochondrial/ER resident chaperone protein tumour necrosis factor receptor associated protein 1 (TRAP1). Identification of a fourth, unrelated patient with autoinflammation and compound heterozygous mutation of TRAP1 alone facilitated further functional studies, confirming the importance of this protein as a chaperone of misfolded proteins with loss of function, which may contribute to autoinflammation. Impaired TRAP1 function leads to cellular stress and elevated levels of serum IL-18. This study emphasizes the importance of considering digenic or oligogenic models of disease in particularly severe phenotypes and suggests that autoinflammatory disease might be enhanced by bi-allelic mutations in TRAP1.

A taste of periodic fever syndromes.

Periodic fevers are acquired or inherited disorders of innate immunity, which were first described in the 1940s. The patients are typically young at onset and have regularly recurring fevers for a few days to a few weeks with systemic inflammatory symptoms that are interrupted by symptom-free periods. There is a variety of clinical manifestations including gastrointestinal complaints, myalgias, arthralgias, and rash. A differential diagnosis in these patients may include recurrent infections, other inflammatory disorders, and neoplastic disease. This clinical review focuses on a sample of autoinflammatory disorders including familial Mediterranean fever, tumor necrosis factor receptor 1-associated periodic syndrome, hyperimmunoglobulinemia D syndrome, the cryopyrin-associated periodic syndrome, and periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis syndrome. We review the basics, pertinent clinical and laboratory features, and management of each entity.

Serum leptin, resistin, visfatin and adiponectin levels in tumor necrosis factor receptor-associated periodic syndrome (TRAPS).

OBJECTIVES: The aims of our study were to evaluate serum leptin, resistin, visfatin and adiponectin levels in patients with tumour necrosis factor receptor-associated periodic syndrome (TRAPS), in comparison to healthy controls, and to correlate their levels to parameters of disease activity and/or severity. METHODS: Serum leptin, resistin, visfatin and adiponectin levels were obtained from 14 TRAPS patients carrying mutations involving cysteine residues, from 16 TRAPS patients carrying other mutations, and from 16 healthy controls. Demographic, clinical and laboratory parameters, including amyloidosis were entered for each patient. Comparisons between groups as well as reciprocal comparisons have been evaluated. RESULTS: Serum leptin, resistin, visfatin and adiponectin did not significantly differ among the 3 groups. Patients carrying cysteine residues mutations showed lower visfatin serum levels than patients carrying other mutations (p<0.02). Serum leptin significantly correlated with the number of attacks/year (multiple R=0.32, multiple adjusted R2= 0.19, p <0.03). Serum adiponectin levels significantly correlated with the presence of amyloidosis (multiple R=0.79, multiple adjusted R2=0.57, p<0.03). Adiponectin values were a significant predictor for amyloidosis (AUC 0.75, 95 CI: 0.56-0.94, p<0.03), with a predicting cut-off value set at 23.16 pg/ml, the predictive positive value was 53.8%. Visfatin serum levels resulted respectively related to leptin (rs=0.42, r2=0.18, p<0.02) and to resistin (rs=0.57, r2=0.32, p<0.01) serum levels; whilst leptin and resistin serum levels did not reciprocally correlate. CONCLUSIONS: Although a prospective design study and larger cohort are mandatory, adipokines serum levels and their correlations with parameters of disease activity and/or severity seem to show a baseline pattern in TRAPS patients.

Successful treatment of a patient with tumor necrosis factor receptor-associated periodic syndrome using a half-dose of etanercept.

TNF receptor-associated periodic syndrome (TRAPS) is caused by mutations of TNFRSF1A gene and characterized by recurrent febrile episodes of prolonged duration and initial good response to steroids. Etanercept, a TNF blocker, has been used as a putative molecular-targeted agent for TRAPS, with some patients showing limited efficacy. Here, we report a patient with TRAPS who recovered from steroid dependency by etanercept and kept remission with a reduced dose of etanercept. The pathophysiology of TRAPS still remains to be elucidated and several hypotheses have been proposed. In the most recent hypothesis, the concerted action of wild-type and mutant TNF receptors plays an important role in provoking enhanced inflammation in TRAPS. The excellent response to etanercept in our patient suggested that there is heterogeneity in TRAPS patients in terms of the contribution of normal TNF signaling to autoinflammation.

[The laboratory approach in the diagnosis of systemic autoinflammatory diseases]. / L'approccio laboratoristico nella diagnostica delle malattie autoinfiammatorie sistemiche.

Systemic autoinflammatory diseases are a group of inherited disorders of the innate immunity characterized by the recurrence of febrile attacks lasting from few hours to few weeks and multi-district inflammation of different severity involving skin, serosal membranes, joints, gastrointestinal tube and central nervous system. The vast majority of these conditions is caused by mutations in genes involved in the control of inflammation and apoptosis mechanisms. The group includes familial Mediterranean fever, mevalonate kinase deficiency syndrome, tumor necrosis factor receptor-associated periodic syndrome, cryopyrin-associated periodic syndromes, hereditary pyogenic and granulomatous disorders. Their diagnostic identification derives from the combination of clinical and biohumoral data, though can be sometimes confirmed by genotype analysis.

A clinical perspective of IL-1ß as the gatekeeper of inflammation.

An expanding spectrum of acute and chronic non-infectious inflammatory diseases is uniquely responsive to IL-1ß neutralization. IL-1ß-mediated diseases are often called "auto-inflammatory" and the dominant finding is the release of the active form of IL-1ß driven by endogenous molecules acting on the monocyte/macrophage. IL-1ß activity is tightly controlled and requires the conversion of the primary transcript, the inactive IL-1ß precursor, to the active cytokine by limited proteolysis. Limited proteolysis can take place extracellularly by serine proteases, released in particular by infiltrating neutrophils or intracellularly by the cysteine protease caspase-1. Therefore, blocking IL-1ß resolves inflammation regardless of how the cytokine is released from the cell or how the precursor is cleaved. Endogenous stimulants such as oxidized fatty acids and lipoproteins, high glucose concentrations, uric acid crystals, activated complement, contents of necrotic cells, and cytokines, particularly IL-1 itself, induce the synthesis of the inactive IL-1ß precursor, which awaits processing to the active form. Although bursts of IL-1ß precipitate acute attacks of systemic or local inflammation, IL-1ß also contributes to several chronic diseases. For example, ischemic injury, such as myocardial infarction or stroke, causes acute and extensive damage, and slowly progressive inflammatory processes take place in atherosclerosis, type 2 diabetes, osteoarthritis and smoldering myeloma. Evidence for the involvement of IL-1ß and the clinical results of reducing IL-1ß activity in this broad spectrum of inflammatory diseases are the focus of this review.

Differential cytokine secretion results from p65 and c-Rel NF-κB subunit signaling in peripheral blood mononuclear cells of TNF receptor-associated periodic syndrome patients.

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) is an autosomal dominant autoinflammatory condition caused by mutations in the TNFRSF1A gene which encodes the tumor necrosis factor (TNF) receptor, TNFR1. We investigated the effect of three high penetrance and three low penetrance TNFRSF1A mutations upon NF-κB transcription factor family subunit activity, and the resulting impact upon secretion of 25 different cytokines. Whilst certain mutations resulted in elevated NF-κB p65 subunit activity, others instead resulted in elevated c-Rel subunit activity. Interestingly, high p65 activity was associated with elevated IL-8 secretion, whereas high c-Rel activity increased IL-1ß and IL-12 secretion. In conclusion, while all six TNFRSF1A mutations showed enhanced NF-κB activity, different mutations stimulated distinct NF-κB family subunit activities, and this in turn resulted in the generation of unique cytokine secretory profiles.

Tumor necrosis factor receptor 1-associated periodic syndrome without fever: cytokine profile before and during etanercept treatment.

The objectives of this study are autoinflammatory syndromes which are usually characterized by repeated attacks of fever, especially in children. The presentation of these diseases, however, varies between entities and between patients of a particular syndrome. We report a 16-year-old female patient, who suffered from periodic erythema and myositis/fasciitis. She experienced at least nine attacks of dermatitis and myositis, while no fever episodes were noted over a 3-year period. A delay of puberty with amenorrhea and a short stature were also present. Laboratory investigations consistently showed markedly increased inflammatory parameters (especially a high serum amyloid A) and dysproteinemia. Because the patient's mother complained about chronic and periodic abdominal pain with also persistently elevated inflammatory parameters, the differential diagnosis included hereditary disorders resulting in chronic inflammation. The diagnosis of an inherited tumor necrosis factor receptor (TNFR) 1-associated periodic syndrome (TRAPS) was confirmed by genetic analyses. Long-term anti-inflammatory treatment with etanercept resulted in a significant clinical improvement and reduction of the inflammatory parameters ESR, CRP, interleukin-6, TNF-α, and soluble TNF-α receptor 1, but not of interleukin-12. Monitoring of the cytokine profile suggested partial effectiveness of etanercept in the treatment of TRAPS. Hereditary fever syndromes have to be considered in case of chronic unexplained inflammation even if fever is no presenting symptom.