Istituti di Ricovero e Cura a Carattere Scientifico

Decision Tree Analysis as a Preliminary Evidence-Based Tool for Identifying the Syndrome of Undifferentiated Recurrent Fever in Children Compared With Hereditary Recurrent Fevers and Periodic Fever, Aphthosis, Pharyngitis, and Adenitis Syndrome.

To develop evidence-based criteria to classify patients with syndrome of undifferentiated recurrent fevers (SURF). One hundred twelve patients with SURF observed in a single tertiary referral center were analyzed. Patients with genetically confirmed hereditary recurrent fever (HRF) or with periodic fever, aphthosis, pharyngitis, and adenitis (PFAPA) syndrome already analyzed for the Eurofever classification criteria were used as disease controls. A decision tree approach was tested by randomly splitting the available data in a training set and in an internal test set. An alternative model using a classical regression model was also analyzed. An external validation for both approaches was performed on 123 patients recruited from four other centers. The decision tree model integrating clinical and genetic data identified 91% of patients with SURF. A decision tree model based solely on clinical variables identified up to 88% of patients with SURF. The logistic regression model including genetic tests exhibited an overall accuracy of 89.2% (95% confidence interval [CI] 81.1-94.7). In contrast, the logistic regression model exclusively based on clinical manifestations displayed an overall accuracy of 66.7% (95% CI 56.1-76.1). When the classification criteria including genetic tests were applied to the external validation cohort, the model demonstrated a strong discriminative power, with areas under the receiver operating characteristic curve of 96.3% using the decision tree model and 88.0% with the logistic regression model. The study shows the possibility of achieving evidence-based criteria that can classify SURF at least with respect to the main HRF and PFAPA syndrome and may be considered as a preliminary tool for the enrollment of more homogeneous cohorts of patients in future studies.

EULAR/ACR classification criteria for paediatric chronic nonbacterial osteomyelitis (CNO).

To develop and validate classification criteria for paediatric chronic nonbacterial osteomyelitis (CNO) jointly supported by the European Alliance of Associations for Rheumatology (EULAR) and the American College of Rheumatology (ACR). This international initiative had 4 phases: (1) candidate items were proposed in a survey of paediatric rheumatologists, (2) criteria definition and reduction by Delphi and nominal group technique exercises, (3) criteria weighting using multicriteria decision analysis, and (4) refinement of weights and threshold score in a development cohort of 441 patients and validation in another cohort of 514 patients. The new EULAR/ACR classification criteria for CNO require typical radiographic or magnetic resonance imaging findings and bone pain as an obligatory entry criterion and exclusion criteria of malignancy, infection, vitamin C deficiency, and hypophosphatasia, followed by additive weighted criteria in 5 clinical (site of bone lesions, pattern of bone lesions, age at onset, coexisting conditions, fever) and 4 pathology/laboratory domains (bone biopsy findings if done, anaemia, C-reactive protein level, and erythrocyte sedimentation rate). A total score ≥55 is required for classification as CNO. The new criteria had a sensitivity of 82% and specificity of 98% in the validation cohort. These new classification criteria for paediatric CNO developed with international input reflect current views about CNO, have high specificity and good sensitivity, and provide a key foundation for future CNO research.

Corticosteroid use in PFAPA syndrome: clinical practice data from the JIR-CliPS Survey Study and a comprehensive literature review.

CS are used to abort disease flares in periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA) syndrome. We aimed to obtain a global overview of physicians' CS usage strategies and analyse the data in the literature regarding CS use in PFAPA syndrome. The Juvenile Inflammatory Rheumatism Clinical Practice Strategies (JIR-CliPS) PFAPA questionnaire included nine questions on CS use in addition to the demographic data questions. The survey was distributed via e-mail to potential respondents. The MEDLINE/PubMed and Scopus databases were searched systematically to extract the data regarding CS use in PFAPA syndrome. From 47 countries, 144 physicians (female/male = 2.6; 67.4% paediatric rheumatologists) answered the survey. Most respondents (n = 133; 92.4%) prescribe CS in PFAPA flares. The most frequently prescribed CS was prednisolone (63.2%). The definition of response to CS was indicated as 'response within 12 h' by the highest number of respondents (n = 61; 42.4%). When CS cause an increase in attack frequency, most (57.9%) consider another treatment if this causes a decrease in quality of life. Forty-four (30.6%) respondents were 'routinely' prescribing CS to PFAPA patients, and this practice was more frequent among more experienced physicians (P < 0.001). We identified 46 articles in the literature describing 4564 PFAPA patients treated with CS. Prednisone was the most frequently preferred CS (48.2%). Response to CS was around 95%, although an increase in attack frequency was noted in almost 35% of the patients. Physicians frequently use CS for PFAPA in their routine clinical practice. Regarding treatment modification, the quality of life was a prominent consideration for physicians.

Predictive factors for therapeutic response and cluster analysis in syndrome of undifferentiated recurrent fever (SURF).

Syndrome of undifferentiated recurrent fever (SURF) refers to a group of recurrent fevers without a clear monogenic cause. Clinical spectrum, treatment response predictors and management strategies remain unclear. This study aims to longitudinally analyse a homogeneously selected cohort of 101 SURF patients, to identify factors associated with colchicine resistance and to evaluate the efficacy of interleukin-1 (IL-1) inhibitors. Patients were enrolled in the Eurofever Registry, carefully excluding those with periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA); familial Mediterranean fever and other known monogenic recurrent fevers. Demographic, clinical and treatment data were analysed to identify predictors of colchicine resistance and define subgroups through cluster analysis. Common symptoms included fever, arthralgia, abdominal pain and myalgia, with PFAPA-like features (lymphadenopathy, tonsillitis, oral aphthae) observed in one-third of cases, sporadically. Colchicine efficacy, assessed in 77 patients, revealed complete response in the majority of patients (61%). Univariable analysis identified PFAPA-like features, including aphthous stomatitis (p=0.001), cervical lymphadenopathy (p=0.012) and exudative tonsillitis (p=0.004), as associated with colchicine resistance. Multivariable analysis confirmed aphthous stomatitis as an independent predictor of resistance (p=0.014). Tonsillectomy was ineffective. IL-1 inhibitors (anakinra, canakinumab) were beneficial in refractory cases. Cluster analysis revealed three distinct subgroups with varying symptoms and colchicine responses. These findings provide new insights into SURF, identifying predictors of colchicine resistance and supporting the efficacy of IL-1 blockade. Cluster analysis suggests the heterogeneity within SURF, reinforcing the need for refined diagnostic criteria and personalised treatment strategies.

Pyrin Inflammasome Activation Defines Colchicine-Responsive SURF Patients from FMF and Other Recurrent Fevers.

Syndrome of undifferentiated recurrent fever (SURF) is characterized by recurrent fevers, a lack of confirmed molecular diagnosis, and a complete or partial response to colchicine. Despite the clinical similarities to familial Mediterranean fever (FMF), the underlying inflammatory mechanisms of SURF are not yet understood. We here analyzed the in vitro activation of the pyrin inflammasome in a cohort of SURF patients compared to FMF and PFAPA patients. Peripheral blood mononuclear cells (PBMC) were collected from SURF (both colchicine-treated and untreated), FMF, PFAPA patients, and healthy donors. PBMC were stimulated ex vivo with Clostridium difficile toxin A (TcdA) and a PKC inhibitor (UCN-01), in the presence or absence of colchicine. The assembly of the pyrin inflammasome was evaluated by measuring the presence of apoptosis-associated Speck-like protein containing caspase recruitment domain (ASC) specks in monocytes using flow cytometry. IL-1β secretion was quantified using an ELISA assay. No differences in TcdA-induced activation of pyrin inflammasome were observed among FMF, PFAPA, and healthy donors. Untreated SURF patients showed a reduced response to TcdA, which was normalized after colchicine treatment. In contrast to FMF, SURF patients, similar to PFAPA patients and healthy donors, did not exhibit pyrin inflammasome activation in response to UCN-01-mediated pyrin dephosphorylation. These data demonstrate that in vitro functional analysis of pyrin inflammasome activation can differentiate SURF from FMF and PFAPA patients, suggesting the involvement of the pyrin inflammasome in the pathophysiology of SURF.

A Potential Link Between Outcome of Periodic Fever, Aphthous Stomatitis, Pharyngitis, Cervical Adenitis (PFAPA) Syndrome in Children and Breastfeeding: A Retrospective Single-Center Cohort Snapshot.

Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis syndrome, often referred to as PFAPA syndrome, may enigmatically recur for an undetermined time in affected children: a potential reason to explain its recurring pattern for an unpredictable period or its self-limitation is currently unknown. We explored the relationship between different general, demographic, clinical, and laboratory features of PFAPA children and disease evolution over the course of a decade. We have retrospectively screened 150 Italian children with a history of PFAPA syndrome attending the Outpatients Clinic of Pediatric Rheumatology in our Institution during the period 2014-2024, all without any recognized chronic diseases: 88 males, 62 females, mean age at onset of 2.5 ± 1.7 years, age range of 0.3-9.4 years, and mean age at diagnosis of 4.5 ± 2.0 years. The whole cohort of PFAPA patients had been followed up for a median period of 5 years (IQR: 4-7). After dividing patients into two groups based on either the disappearance or persistence of PFAPA symptoms during follow-up, we found that positive family history of recurring fevers, cervical lymphadenopathy, arthralgia, myalgia, and breastfeeding for more than 6 months were associated with the disappearance of febrile attacks for at least six months. Performing a multivariate analysis adjusted for sex and age, we found that only breastfeeding duration longer than 6 months and higher education level of PFAPA patients' mothers were independently associated with the resolution of PFAPA symptoms.

Current Evidence on Vaccinations in Pediatric and Adult Patients with Systemic Autoinflammatory Diseases.

Systemic autoinflammatory diseases (SAIDs) are defined by recurrent febrile attacks associated with protean manifestations involving joints, the gastrointestinal tract, skin, and the central nervous system, combined with elevated inflammatory markers, and are caused by a dysregulation of the innate immune system. From a clinical standpoint, the most known SAIDs are familial Mediterranean fever (FMF); cryopyrin-associated periodic syndrome (CAPS); mevalonate kinase deficiency (MKD); and periodic fever, aphthosis, pharyngitis, and adenitis (PFAPA) syndrome. Current guidelines recommend the regular sequential administration of vaccines for all individuals with SAIDs. However, these patients have a much lower vaccination coverage rates in 'real-world' epidemiological studies than the general population. The main purpose of this review was to evaluate the scientific evidence available on both the efficacy and safety of vaccines in patients with SAIDs. From this analysis, neither serious adverse effects nor poorer antibody responses have been observed after vaccination in patients with SAIDs on treatment with biologic agents. More specifically, no new-onset immune-mediated complications have been observed following immunizations. Post-vaccination acute flares were significantly less frequent in FMF patients treated with colchicine alone than in those treated with both colchicine and canakinumab. Conversely, a decreased risk of SARS-CoV-2 infection has been proved for patients with FMF after vaccination with the mRNA-based BNT162b2 vaccine. Canakinumab did not appear to affect the ability to produce antibodies against non-live vaccines in patients with CAPS, especially if administered with a time lag from the vaccination. On the other hand, our analysis has shown that immunization against , specifically with the pneumococcal polysaccharide vaccine, was associated with a higher incidence of adverse reactions in CAPS patients. In addition, disease flares might be elicited by vaccinations in children with MKD, though no adverse events have been noted despite concurrent treatment with either anakinra or canakinumab. PFAPA patients seem to be less responsive to measles, mumps, and rubella-vaccine, but have shown higher antibody response than healthy controls following vaccination against hepatitis A. In consideration of the clinical frailty of both children and adults with SAIDs, all vaccinations remain 'highly' recommended in this category of patients despite the paucity of data available.

Response to: 'Do we need the PFAPA syndrome in adults with non-monogenic periodic fevers?' by Fayand .

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

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. 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-TCRαβ+ 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. 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 TCRαβ+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 TCRαβ+B220+ lymphocytes. Oliveira's required criteria are useful for the early suspicion of ALPS. TCRαβ+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.

Children and Adults with PFAPA Syndrome: Similarities and Divergences in a Real-Life Clinical Setting.

Analogies or differences of periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome in children and adults are barely known. The aim of our study was to compare the overall characteristics of a large cohort of patients, both children and adults, diagnosed with PFAPA syndrome. In the last decade, we identified 120 children and 63 adults with periodically recurring fevers, who fulfilled the criteria for PFAPA diagnosis. The two subcohorts were analyzed according to demographic features, clinical manifestations, laboratory data, and responses to therapies. The mean age of onset was 2.4 ± 1.5 and 19.7 ± 10.3 years, respectively, in children and adults, while attacks occurred every 3.8 ± 0.8 and every 4.3 ± 2.3 weeks, respectively, in children and adults. A higher prevalence of exudative pharyngitis was observed in children (58.8%), and the majority of children had only two cardinal signs during flares. In adults, there was a higher interpersonal variability of the intercritical periods. Inflammatory markers measured during non-febrile periods were normal in children but altered in the totality of adults during febrile periods. A strong efficacy of corticosteroids in controlling the pediatric syndrome was observed, but response rates to steroids were less brilliant in adults. Colchicine and interleukin-1 inhibitors were used in the management of the steroid-resistant adult syndrome. Conversely, tonsillectomy was performed in a very low number of children, but was effective in 60.7% of adults when treated after 16 years. The mean age of disappearance of PFAPA symptoms has been 6.4 ± 2.4 years in children, while only 27% of adults have shown a complete drug-free symptom regression. A linear conformity of the PFAPA syndrome has been observed between pediatric and adult patients. PFAPA symptoms tended to disappear with no sequelae in 94.1% of children, while the disease was still active in almost 3/4 of adults at the time of our assessment.

Periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA) syndrome: A debate about diagnosis and treatment in children continues.

Next generation sequencing panel in undifferentiated autoinflammatory diseases identifies patients with colchicine-responder recurrent fevers.

The number of innate immune system disorders classified as systemic autoinflammatory diseases (SAID) has increased in recent years. More than 70% of patients with clinical manifestations of SAID did not receive a molecular diagnosis, thus being classed as so-called undifferentiated or undefined SAID (uSAID). The aim of the present study was to evaluate a next-generation sequencing (NGS)-based clinically oriented protocol in patients with uSAID. We designed a NGS panel that included 41 genes clustered in seven subpanels. Patients with uSAID were classified into different groups according to their clinical features and sequenced for the coding portions of the 41 genes. Fifty patients were enrolled in the study. Thirty-four patients (72%) displayed recurrent fevers not consistent with a PFAPA phenotype. Sixteen patients displayed a chronic inflammatory disease course. A total of 100 gene variants were found (mean 2 per patient; range 0-6), a quarter of which affected suspected genes. Mutations with a definitive diagnostic impact were detected in two patients. Patients with genetically negative recurrent fevers displayed a prevalent gastrointestinal, skin and articular involvement. Patients responded to steroids on demands (94%) and colchicine, with a response rate of 78%. Even with a low molecular diagnostic rate, a NGS-based approach is able to provide a final diagnosis in a proportion of uSAID patients with evident cost-effectiveness. It also allows the identification of a subgroup of genetically negative patients with recurrent fever responding to steroid on demand and colchicine.

Current Therapeutic Options for the Main Monogenic Autoinflammatory Diseases and PFAPA Syndrome: Evidence-Based Approach and Proposal of a Practical Guide.

Monogenic autoinflammatory diseases are rare conditions caused by genetic abnormalities affecting the innate immunity. Previous therapeutic strategies had been mainly based on results from retrospective studies and physicians' experience. However, during the last years, the significant improvement in their genetic and pathogenic knowledge has been accompanied by a remarkable progress in their management. The relatively recent identification of the inflammasome as the crucial pathogenic mechanism causing an aberrant production of interleukin 1β (IL-1β) in the most frequent monogenic autoinflammatory diseases led to the introduction of anti-IL-1 agents and other biologic drugs as part of the previously limited therapeutic armamentarium available. Advances in the treatment of autoinflammatory diseases have been favored by the use of new biologic agents and the performance of a notable number of randomized clinical trials exploring the efficacy and safety of these agents. Clinical trials have contributed to increase the level of evidence and provided more robust therapeutic recommendations. This review analyzes the treatment of the most frequent monogenic autoinflammatory diseases, namely, familial Mediterranean fever, tumor necrosis factor receptor-associated periodic fever syndrome, hyperimmunoglobulin D syndrome/mevalonate kinase deficiency, and cryopyrin-associated periodic syndromes, together with periodic fever with aphthous stomatitis, pharyngitis, and cervical adenitis syndrome, which is the most common polygenic autoinflammatory disease in children, also occurring in adult patients. Finally, based on the available expert consensus recommendations and the highest level of evidence of the published studies, a practical evidence-based guideline for the treatment of these autoinflammatory diseases is proposed.

Rare missense variants in the ALPK1 gene may predispose to periodic fever, aphthous stomatitis, pharyngitis and adenitis (PFAPA) syndrome.

PFAPA is an autoinflammatory syndrome characterized by periodic fever, aphthous stomatitis, sterile pharingitis, and adenitis, with an onset usually before the age of five. While the condition is most commonly sporadic, a few cases are familial and are usually compatible with an autosomal dominant (AD) transmission pattern, with reduced penetrance in some pedigrees. We performed exome analysis in a family where PFAPA was present in three relatives in two generations showing apparent AD segregation, identifying several rare and/or novel heterozygous variants in genes involved in the autoinflammatory pathway. Following segregation analysis of candidate variants, only one, c. 2770T>C p.(S924P) in the ALPK1 gene, was found to be consistently present in affected family members. ALPK1 is broadly expressed in different tissues and its protein is the intracellular kinase activated by the bacterial ADP-heptose bisphosphate that phosphorylates and activates TRAF-Interacting protein with Forkhead-Associated domain (TIFA) and triggers the immediate response to Gram-negative bacterial invasion. Sequencing analysis of 13 additional sporadic cases and 10 familial PFAPA cases identified two additional heterozygous missense variants c.1024G>C p.(D342H) and c.710C>T p.(T237M) in two sporadic patients, suggesting that rare variants in ALPK1 may represent a predisposing factor for recurrent periodic fever in a pediatric population.

Treatment options for periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome in children and adults: a narrative review.

Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome is the most frequent non-hereditary autoinflammatory disorder in childhood: Its onset is usually observed before 5 years, though reports regarding adulthood are increasing. The pathogenesis of the syndrome is not completely understood, but a multifactorial origin, probably based on a polygenic pattern of susceptibility, is the most probable rational pathogenetic hypothesis. Treatment of PFAPA syndrome relies on the administration of low-dose corticosteroids, which promptly abort flares but cannot prevent subsequent disease episodes over time. Tonsillectomy with or without adenoidectomy has proved to be successful in some pediatric patients, as proven by different studies. On the other hand, colchicine, cimetidine, nonsteroidal anti-inflammatory drugs, and interleukin-1 inhibitors have shown efficacy, which require further definite confirmations. This review is aimed at summarizing all the recent evidence about treatment options available for PFAPA syndrome both in pediatric and adult patients.

Classification criteria for autoinflammatory recurrent fevers.

Different diagnostic and classification criteria are available for hereditary recurrent fevers (HRF)-familial Mediterranean fever (FMF), tumour necrosis factor receptor-associated periodic fever syndrome (TRAPS), mevalonate kinase deficiency (MKD) and cryopyrin-associated periodic syndromes (CAPS)-and for the non-hereditary, periodic fever, aphthosis, pharyngitis and adenitis (PFAPA). We aimed to develop and validate new evidence-based classification criteria for HRF/PFAPA. Step 1: selection of clinical, laboratory and genetic candidate variables; step 2: classification of 360 random patients from the Eurofever Registry by a panel of 25 clinicians and 8 geneticists blinded to patients' diagnosis (consensus ≥80%); step 3: statistical analysis for the selection of the best candidate classification criteria; step 4: nominal group technique consensus conference with 33 panellists for the discussion and selection of the final classification criteria; step 5: cross-sectional validation of the novel criteria. The panellists achieved consensus to classify 281 of 360 (78%) patients (32 CAPS, 36 FMF, 56 MKD, 37 PFAPA, 39 TRAPS, 81 undefined recurrent fever). Consensus was reached for two sets of criteria for each HRF, one including genetic and clinical variables, the other with clinical variables only, plus new criteria for PFAPA. The four HRF criteria demonstrated sensitivity of 0.94-1 and specificity of 0.95-1; for PFAPA, criteria sensitivity and specificity were 0.97 and 0.93, respectively. Validation of these criteria in an independent data set of 1018 patients shows a high accuracy (from 0.81 to 0.98). Eurofever proposes a novel set of validated classification criteria for HRF and PFAPA with high sensitivity and specificity.

Early onset PFAPA-like syndrome in a child with microduplication of the 7q11.23.

An international delphi survey for the definition of the variables for the development of new classification criteria for periodic fever aphtous stomatitis pharingitis cervical adenitis (PFAPA).

Diagnosis of Periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA) is currently based on a set of criteria proposed in 1999 modified from Marshall's criteria. Nevertheless no validated evidence based set of classification criteria for PFAPA has been established so far. The aim of this study was to identify candidate classification criteria PFAPA syndrome using international consensus formation through a Delphi questionnaire survey. A first open-ended questionnaire was sent to adult and pediatric clinicians/researchers, asking to identify the variables thought most likely to be helpful and relevant for the diagnosis of PFAPA. In a second survey, respondents were asked to select, from the list of variables coming from the first survey, the 10 features that they felt were most important, and to rank them in descending order from most important to least important. The response rate to the first and second Delphi was respectively 109/124 (88%) and 141/162 (87%). The number of participants that completed the first and second Delphi was 69/124 (56%) and 110/162 (68%). From the first Delphi we obtained a list of 92 variables, of which 62 were selected in the second Delphi. Variables reaching the top five position of the rank were regular periodicity, aphthous stomatitis, response to corticosteroids, cervical adenitis, and well-being between flares. Our process led to identification of features that were felt to be the most important as candidate classification criteria for PFAPA by a large sample of international rheumatologists. The performance of these items will be tested further in the next phase of the study, through analysis of real patient data.

The Broad-Ranging Panorama of Systemic Autoinflammatory Disorders with Specific Focus on Acute Painful Symptoms and Hematologic Manifestations in Children.

Systemic autoinflammatory disorders (SAIDs) are inherited defects of innate immunity characterized by recurrent sterile inflammatory attacks involving skin, joints, serosal membranes, gastrointestinal tube, and other tissues, which recur with variable rhythmicity and display reactive amyloidosis as a potential long-term complication. Dysregulated inflammasome activity leading to overproduction of many proinflammatory cytokines, such as interleukin-1 (IL-1), and delayed shutdown of inflammation are considered crucial pathogenic keys in the vast majority of SAIDs. Progress of cellular biology has partially clarified the mechanisms behind monogenic SAIDs, such as familial Mediterranean fever, tumor necrosis factor receptor-associated periodic syndrome, cryopyrin-associated periodic syndrome, mevalonate kinase deficiency, hereditary pyogenic diseases, idiopathic granulomatous diseases and defects of the ubiquitin-proteasome pathway. Whereas, little is clarified for the polygenic SAIDs, such as periodic fever, aphthous stomatitis, pharyngitis, and cervical adenopathy (PFAPA) syndrome. The puzzle of symptomatic febrile attacks recurring over time in children requires evaluating the mixture of clinical data, inflammatory parameters in different disease phases, the therapeutic efficacy of specific drugs such as colchicine, corticosteroids or IL-1 antagonists, and genotype analysis in selected cases. The long-term history of periodic fevers should also need to rule out chronic infections and malignancies. This review is conceived as a practical template for proper classification of children with recurring fevers and includes tips useful for the diagnostic approach to SAIDs, focusing on the specific acute painful symptoms and hematologic manifestations encountered in childhood.

Evidence-based provisional clinical classification criteria for autoinflammatory periodic fevers.

The objective of this work was to develop and validate a set of clinical criteria for the classification of patients affected by periodic fevers. Patients with inherited periodic fevers (familial Mediterranean fever (FMF); mevalonate kinase deficiency (MKD); tumour necrosis factor receptor-associated periodic fever syndrome (TRAPS); cryopyrin-associated periodic syndromes (CAPS)) enrolled in the Eurofever Registry up until March 2013 were evaluated. Patients with periodic fever, aphthosis, pharyngitis and adenitis (PFAPA) syndrome were used as negative controls. For each genetic disease, patients were considered to be 'gold standard' on the basis of the presence of a confirmatory genetic analysis. Clinical criteria were formulated on the basis of univariate and multivariate analysis in an initial group of patients (training set) and validated in an independent set of patients (validation set). A total of 1215 consecutive patients with periodic fevers were identified, and 518 gold standard patients (291 FMF, 74 MKD, 86 TRAPS, 67 CAPS) and 199 patients with PFAPA as disease controls were evaluated. The univariate and multivariate analyses identified a number of clinical variables that correlated independently with each disease, and four provisional classification scores were created. Cut-off values of the classification scores were chosen using receiver operating characteristic curve analysis as those giving the highest sensitivity and specificity. The classification scores were then tested in an independent set of patients (validation set) with an area under the curve of 0.98 for FMF, 0.95 for TRAPS, 0.96 for MKD, and 0.99 for CAPS. In conclusion, evidence-based provisional clinical criteria with high sensitivity and specificity for the clinical classification of patients with inherited periodic fevers have been developed.

Treatment of autoinflammatory diseases: results from the Eurofever Registry and a literature review.

To evaluate the response to treatment of autoinflammatory diseases from an international registry and an up-to-date literature review. The response to treatment was studied in a web-based registry in which clinical information on anonymised patients with autoinflammatory diseases was collected retrospectively as part of the Eurofever initiative. Participating hospitals included paediatric rheumatology centres of the Paediatric Rheumatology International Trial Organisation network and adult centres with a specific interest in autoinflammatory diseases. The following diseases were included: familial Mediterranean fever (FMF), cryopyrin-associated periodic syndromes (CAPS), tumour necrosis factor (TNF)-receptor associated periodic syndrome (TRAPS), mevalonate kinase deficiency (MKD), pyogenic arthritis pustulosis acne (PAPA) syndrome, deficiency of interleukin-1 receptor antagonist (DIRA), NLRP12-related periodic fever and periodic fever aphthosis pharyngitis adenitis (PFAPA) syndrome. Cases were independently validated by experts for each disease. A literature search regarding treatment of the abovementioned diseases was also performed using Medline and Embase. 22 months from the beginning of the enrolment, complete information on 496 validated patients was available. Data from the registry in combination with evidence from the literature confirmed that colchicine is the treatment of choice for FMF and IL-1 blockade for DIRA and CAPS. Corticosteroids on demand probably represent a valid therapeutic strategy for PFAPA, but also for MKD and TRAPS. Patients with poorly controlled MKD, TRAPS, PAPA or FMF may benefit from IL-1 blockade; anti-TNF treatment may represent a possible valuable alternative. In the absence of high-grade evidence, these results could serve as a basis for therapeutic guidelines and to identify candidate drugs for future therapeutic trials.

Different presentations in patients with tumor necrosis factor receptor-associated periodic syndrome mutations: report of two cases.

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) is an autosomal dominant autoinflammatory disorder caused by mutations in the TNFRSF1A gene encoding the 55-kDa receptor for tumor necrosis factor (TNF)-α. It is characterized by recurrent prolonged episodes of fever accompanied by abdominal pain, pleuritis, migratory skin rashes, fasciitis, headache, conjunctivitis, and periorbital edema. We report two children, one with a severe mutation in the TNFRSF1A gene causing the typical phenotype. The second patient had a homozygous R92Q-type mutation and displayed a periodic fever with aphthous stomatitis, pharyngitis and adenitis (PFAPA) syndrome-like phenotype. In the eastern Mediterranean region, TRAPS is probably underdiagnosed because of the overwhelming frequency of familial Mediterranean fever (FMF). However, TRAPS should be sought for in patients with atypical symptoms for FMF.

Long-term clinical profile of children with the low-penetrance R92Q mutation of the TNFRSF1A gene.

To analyze the long-term impact of the R92Q mutation of TNFRSF1A in children with periodic fever, in comparison with children with tumor necrosis factor receptor-associated periodic syndrome (TRAPS) with TNFRSF1A structural mutations and children with periodic fever of unknown origin fulfilling the criteria for periodic fever, aphthosis, pharyngitis, and adenitis syndrome (PFAPA). The extracellular region of TNFRSF1A was analyzed in 720 consecutive children with periodic fever, using denaturing high-performance liquid chromatography and DNA sequencing. Followup data on 11 pediatric patients with TNFRSF1A structural mutations (cysteine or T50M), 23 pediatric patients with an R92Q substitution, and 64 pediatric patients with PFAPA were collected during routine clinic visits. The 50-item Child Health Questionnaire was used to assess health-related quality of life (HRQOL). The frequency of typical TRAPS-related clinical manifestations was significantly lower and the impact of the disease on HRQOL was significantly reduced in patients with the R92Q mutation compared with TRAPS patients carrying structural mutations of TNFRSF1A. Followup data on 11 TRAPS patients with TNFRSF1A structural mutations (mean followup 7.9 years), 16 patients with theR92Q substitution (mean followup 7.3 years), and 64 patients with PFAPA (mean followup 5.2 years) were available. Patients with R92Q mutations and patients with PFAPA displayed a higher rate of self-resolution or amelioration of the fever episodes than did TRAPS patients with structural mutations. Although some cases may progress to a more chronic disease course, the majority of children with an R92Q mutation of the TNFRSFA1 gene show a milder disease course than that in children with TNFRSFA1 structural mutations and have a high rate of spontaneous resolution and amelioration of the recurrent fever episodes.

Anti-α-enolase Antibodies in Serum from Pediatric Patients Affected by Inflammatory Diseases: Diagnostic and Pathogenetic Insights.

Human glycolytic enzyme α-enolase was associated with human diseases and with inflammation. An ELISA test was developed to measure anti-α-enolase AAE IgG and AAE IgA in the serum from patients affected by inflammatory diseases with the purpose to evaluate it as a novel diagnostic marker. 80 healthy blood donors and 194 paediatric patients affected by Juvenile idiopathic arthritis (JIA), celiac disease (CD), Crohn's Disease (CrD), hereditary periodic fever (HPF), and PFAPA syndrome were included in the study. HPF patients showed high levels of AAE antibodies, whereas JIA, CD, and CrD presented only partial results. Benign fevers such as PFAPA were almost negative for AAE Abs. These findings suggested that the genetic dysfunction of inflammasome associated with HPF could lead to the formation of AAE Abs that could be used for an early and easy diagnosis.

Outcome of tonsillectomy in selected patients with PFAPA syndrome.

To assess the practicability of integrated medical and surgical management and the effectiveness of tonsillectomy in children with PFAPA syndrome (periodic fever, aphthous stomatitis, pharyngitis, and cervical lymphadenopathy). A prospective study. Secondary pediatric and otolaryngological university center. Of 30 patients evaluated for periodic fever, 18 children with PFAPA syndrome were included in the study. Patients underwent long-term pediatric and otolaryngological assessments, and their parents were asked to keep monthly diaries with reports of any subsequent episodes, symptom, and related sign. Patients received traditional medical therapies, and 9 patients underwent tonsillectomy for the lack of lasting recovery. The association between postoperative outcomes and age at tonsillectomy and the differences in the patients' condition before and after tonsillectomy were statistically tested. In addition, the removed tonsillar tissue was analyzed molecularly to evaluate concomitant infections. All of the surgical patients reported a symptomatic improvement, with complete clinical recovery in 5 cases (56%) and significant reduction in number (P = .005) and duration (P = .03) of recurrences in the remaining 4 (44%). Results of molecular analysis of tonsillar specimens were negative for bacteria in all but 1 patient. Otolaryngologists should be trained to recognize PFAPA syndrome, for which management consists of a regular and prolonged second-level pediatric and otolaryngological follow-up, with surgery only after the failure of traditional medical therapy.