Centre de Référence des Maladies Autoinflammatoires et des Amyloses

Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Cervical Adenitis (PFAPA) Syndrome in Children-From Pathogenesis to Treatment Strategies: A Comprehensive Review.

Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome is the most frequent periodic fever syndrome in non-Mediterranean children, usually manifesting before the age of 5 years. It is characterized by clockwork episodes of fever lasting 3-7 days, accompanied by aphthous stomatitis, pharyngitis, and/or cervical adenitis. Typically, patients with PFAPA are generally well between episodes and exhibit normal growth and development. Although PFAPA often resolves spontaneously, its recurrent nature can significantly impact quality of life, and symptoms may persist into adulthood. This narrative review aimed to consolidate current knowledge on PFAPA epidemiology, pathogenesis, clinical presentation, diagnostic considerations, and therapeutic options. A structured literature search was performed using PubMed, Cochrane Library, and Scopus, focusing on relevant articles specifically addressing PFAPA. Increasing evidence suggests multifactorial pathogenesis involving innate immune dysregulation, activation of the NLRP3 inflammasome, and Th1-driven inflammation. Genetic analysis studies suggest a polygenic inheritance of PFAPA, linking it to immune pathways shared with familial Mediterranean fever and Behçet's disease. Diagnosis remains clinical, though genetic testing may be warranted in specific cases. Management strategies vary owing to the absence of standardized guidelines. Oral corticosteroids are highly effective for acute episodes but may shorten the interval between flares. Among preventive therapies, colchicine appears to reduce attack frequency, although evidence of its efficacy is limited, while tonsillectomy is often considered curative but recommended for patients with refractory disease or when there is a concurrent otolaryngologic indication. Further research is needed to refine diagnostic criteria and optimize treatment strategies, ultimately improving patients' and caregivers' quality of life.

Symptom course of PFAPA syndrome.

Periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA) syndrome is the most common cause of autoinflammatory periodic fever in children. It is generally considered to be a self-limiting condition that resolves spontaneously over time. To evaluate age and delay to recovery of patients with PFAPA syndrome. We retrospectively reviewed the medical records of patients diagnosed with PFAPA syndrome at the Versailles Hospital (Paris, France) and included in the Juvenile Inflammatory Rheumatism (JIR) cohort between 2016 and February 2023. Recovery was defined as the absence of any febrile PFAPA episode in the past year. Patients with either no reported febrile episode or insufficient information on fever status over the last 12 months were contacted by telephone. 209 patients with PFAPA syndrome were included. Overall, 56 (27%) patients experienced resolution of periodic fever, 119 (57%) were still active and 34 (16%) patients were lost to follow-up. Among recovered patients, the median duration of symptoms was 5.43 years (Q1-Q3: 2.97–8.65) and the median age at last febrile episode was 8.34 years (Q1-Q3: 5.44–10.24). Of the 119 patients with persistent fever, 10 patients were initially declared cured but relapsed. In patients whose fever resolved, most experienced their last febrile episode before adolescence. The identification of relapses after at least 12 months without a febrile episode raises questions about the definition of recovery.

Unravelling the clinical heterogeneity of undefined recurrent fever over time in the European registries on Autoinflammation.

Systemic autoinflammatory disorders (SAIDs) represent a growing spectrum of diseases characterized by dysregulation of the innate immune system. The most common pediatric autoinflammatory fever syndrome, Periodic Fever, Aphthous Stomatitis, Pharyngitis, Adenitis (PFAPA), has well defined clinical diagnostic criteria, but there is a subset of patients who do not meet these criteria and are classified as undefined autoinflammatory diseases (uAID). This project, endorsed by PRES, supported by the EMERGE fellowship program, aimed to analyze the evolution of symptoms in recurrent fevers without molecular diagnosis in the context of undifferentiated AIDs, focusing on PFAPA and syndrome of undifferentiated recurrent fever (SURF), using data from European AID registries. Data of patients with PFAPA, SURF and uSAID were collected from 3 registries including detailed epidemiological, demographic and clinical data, results of the genetic testing and additional laboratory investigations with retrospective application of the modified Marshall and PRINTO/Eurofever classification criteria on the cohort of PFAPA patients and preliminary SURF criteria on uSAID/SURF patients. Clinical presentation of PFAPA is variable and some patients did not fit the conventional PFAPA criteria and exhibit different symptoms. Some patients did not meet the criteria for either PFAPA or SURF, highlighting the heterogeneity within these groups. The study also explored potential overlaps between PFAPA and SURF/uAID, revealing that some patients exhibited symptoms characteristic of both conditions, emphasizing the need for more precise classification criteria. Patients with recurrent fevers without molecular diagnoses represent a clinically heterogeneous group. Improved classification criteria are needed for both PFAPA and SURF/uAID to accurately identify and manage these patients, ultimately improving clinical outcomes.

Update on ocular manifestations of the main monogenic and polygenic autoinflammatory diseases.

Autoinflammatory diseases include disorders with a genetic cause and also complex syndromes associated to polygenic or multifactorial factors. Eye involvement is present in many of them, with different extent and severity. The present review covers ophthalmological lesions in the most prevalent monogenic autoinflammatory diseases, including FMF (familial Mediterranean fever), TRAPS (TNF receptor-associated periodic syndrome), CAPS (cryopyrin-associated periodic syndromes), Blau syndrome, DADA2 (deficiency of adenosine deaminase 2), DITRA (deficiency of the interleukin-36 receptor antagonist), other monogenic disorders, including several ubiquitinopathies, interferonopathies, and the recently described ROSAH (retinal dystrophy, optic nerve edema, splenomegaly, anhidrosis, and headache) syndrome, and VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome. Among polygenic autoinflammatory diseases, ocular manifestations have been reviewed in Behçet's disease, PFAPA (periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis) syndrome, Still's disease and autoinflammatory bone diseases, which encompass CRMO (chronic recurrent multifocal osteomyelitis) and SAPHO (synovitis, acne, pustulosis, hyperostosis and osteitis) syndrome.

TNFRSF1A-pR92Q variant identifies a subset of patients more similar to systemic undifferentiated recurrent fever than TNF receptor-associated periodic syndrome.

To describe the clinical phenotype and response to treatment of autoinflammatory disease (AID) patients with the TNFRSF1A-pR92Q variant compared to patients with tumour necrosis factor receptor-associated periodic syndrome (TRAPS) due to pathogenic mutations in the same gene and patients diagnosed with other recurrent fever syndromes including periodic fever with aphthous stomatitis, pharyngitis, and adenitis (PFAPA) and syndrome of undefined recurrent fever (SURF). Clinical data from pR92Q variant associated AID, classical TRAPS, PFAPA and SURF patients were obtained from the Eurofever registry, an international, multicentre registry enabling retrospective collection of data on AID patients. In this study, 361 patients were enrolled, including 77 pR92Q variant, 72 classical TRAPS, 152 PFAPA and 60 SURF patients. pR92Q carriers had an older age of disease onset than classical TRAPS and PFAPA patients. Compared to pR92Q variant patients, classical TRAPS patients had more relatives affected and were more likely to have migratory rash and AA-amyloidosis. Despite several differences in disease characteristics and symptoms between pR92Q variant and PFAPA patients, part of the pR92Q variant patients experienced PFAPA-like symptoms. pR92Q variant and SURF patients showed a comparable clinical phenotype. No major differences were observed in response to treatment between the four patient groups. Steroids were most often prescribed and effective in the majority of patients. Patients with AID carrying the TNFRSF1A-pR92Q variant behave more like SURF patients and differ from patients diagnosed with classical TRAPS and PFAPA in clinical phenotype. Hence, they should no longer be diagnosed as having TRAPS and management should differ accordingly.

Do we need the PFAPA syndrome in adults with non-monogenic periodic fevers?

Suboptimal vaccination coverage of recommended vaccines among French children with recurrent autoinflammatory fever syndromes: a study from the Juvenile Inflammatory Rheumatism cohort.

To determine vaccination coverage among a French cohort of children with recurrent autoinflammatory fever syndromes (RFS). All RFS children aged 2 to 19 years from the Juvenile Inflammatory Rheumatism cohort and followed at the French Reference Center for Autoinflammatory Diseases, Versailles Hospital, were included in our observational study. Immunisation status at ages 2, 7 and 15 years and at the last outpatient visit was evaluated according to the standard French vaccine schedule and recommended supplementary vaccines for patients with immunosuppressive therapy. Of 200 patients, 90 (45%) had periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome; 52 (26%) had familial Mediterranean fever and 50 (25%) had undefined recurrent fever. Complete immunisation as per the standard schedule was obtained by 32% of patients at 2 years, 28% at 7 years, 6% at 15 years and 44% at the last outpatient visit. Similar or higher coverage was obtained by the last outpatient visit for most vaccines, compared to immunisation coverage at 2 years: pneumococcus (91% vs 88%), diphtheria tetanus poliomyelitis (82% vs 86%), hepatitis B (79% vs 69%) and measles, mumps, rubella (91% vs 50%). No patients with immunosuppressive therapy (n = 14) were up to date for all supplementary immunisations recommended for them. Vaccination coverage for RFS children is suboptimal, especially for infants who present with recurrent febrile episodes. The initial vaccination delay is partially corrected through specialist follow-up in later years. Coverage according to the supplementary vaccine recommendations for immunosuppressed patients is poor. Key Points • Vaccination coverage for RFS children is suboptimal, especially at 2 years of age which is likely due to the prevalence of early recurrent febrile symptoms. • The initial vaccination delay is partially recovered during later follow-up at an expert rheumatology center. • Specific recommendations are particularly difficult to apply to patients on immunosuppressive therapy.

Validation of the new classification criteria for hereditary recurrent fever in an independent cohort: experience from the JIR Cohort Database.

The new classification criteria for the hereditary recurrent fever (HRF) syndrome [cryopyrin-associated periodic syndrome (CAPS), TNF-α receptor-associated periodic syndrome (TRAPS), FMF and mevalonate kinase deficiency] have been published recently. These criteria define two core sets of criteria for each HRF: mixed criteria, including genetic and clinical variables, and clinical criteria, relying on clinical variables only. Our aim was to validate the criteria for HRF in an independent cohort, the JIR Cohort database, an international repository of systemic inflammatory diseases. We enrolled patients with HRF, periodic fever, adenitis, pharyngitis and aphthous stomatitis syndrome (PFAPA) and syndrome of undefined recurrent fever (SURF). A score ranging from zero to two was attributed to their respective genotypes: zero (no mutation), one (non-confirmatory genotype) or two (confirmatory genotype). The criteria were applied to all patients based on genotype scoring. The treating physician's diagnosis served as the gold standard for the determination of specificity. We included 455 patients. The classification criteria showed excellent specificity for CAPS and TRAPS (98% specificity each), fair specificity for FMF (88%), but poor specificity for mevalonate kinase deficiency (58%). Sub-analysis showed excellent accuracy of the mixed criteria for all four HRFs. Misclassification was mainly attributable to clinical criteria sets, with false-positive patients in all four HRF clinical criteria sets. This study represents the final validation step of the HRF classification criteria as recommended by the ACR. Genetic data appear to be necessary to classify patients with HRF correctly.

Increased Prevalence of Q703K Variant Among Patients With Autoinflammatory Diseases: An International Multicentric Study.

The inflammasome has been recognized as one of the key components of innate immunity. Gain-of-function mutations in the exon 3 of gene have been implicated in inflammatory diseases suggesting the presence of functionally important sites in this region. Q703K (c.2107C>A, p.Gln703Lys, also known in the literature as Q705K) is a common variant of , that has been considered to be both clinically unremarkable or disease-causing with a reduced penetrance. We aimed to investigate the potential genetic impact of the variant Q703K in patients with recurrent fever presenting with two autoinflammatory diseases: PFAPA (periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis) and CAPS (cryopyrin-associated periodic syndrome), as well as with undefined autoinflammatory disease (uAID). This is an international multicentric observational retrospective study characterizing the clinical phenotype of patients presenting with recurrent fever suspected to be of auto-inflammatory origin and where the Q703K variant was found. Monocytes of parents of 6 Q703K+ PFAPA patients were studied and levels of pro-inflammatory cytokines produced by monocytes of Q703K+ and Q703K- parents have been compared by ELISA. We report 42 patients with the Q703K genetic variant: 21 were PFAPA patients, 6 had a CAPS phenotype, and 15 had an uAID. The phenotypes of PFAPA, CAPS and uAID were quite similar between Q703K positive and negative patients with the exception of increased prevalence of pharyngitis in the Q703K positive CAPS population compared to the negative one. The production of IL-1β was not significantly different between Q703K+ and Q703K- monocytes from asymptomatic parents. The evidence we report in our study shows an increased prevalence of Q703K in patients with autoinflammatory diseases, suggesting an association between the Q703K variant and the risk of PFAPA, CAPS and uAID syndromes. However, we did not show a functional effect of this mutation on the inflammasome basal activity.

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.

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.

Clinical dose effect and functional consequences of R92Q in two families presenting with a TRAPS/PFAPA-like phenotype.

TNF receptor-associated syndrome (TRAPS) is a dominantly inherited autoinflammatory condition caused by mutations in the gene. The mechanism underlying the variable expressivity of the common variant R92Q (rs4149584; c.362G>A; p.Arg121Gln) is unclear and is of critical importance for patient care and genetic counseling. This study evaluated the impact of the number of R92Q mutations in two unique unrelated families. Two patients with undefined but clear autoinflammatory symptoms were referred for genetic diagnosis. Blood samples were collected from the available family members to screen autoinflammatory genes and assess key steps of the TNFR1-mediated signaling pathway using flow cytometry and ex vivo culture. R92Q homozygosity was demonstrated for the two probands. In family 1, the segregation analysis revealed TRAPS-like symptoms in all carriers, with a more severe presentation in the proband, whereas in family 2, the heterozygous parents were totally asymptomatic, suggesting recessive transmission. Functional studies revealed a nonclassical pathogenesis of TRAPS in the two probands and suggested a compensatory mechanism without clear dose effect. We observed for the first time a possible clinical dose effect of R92Q. This work highlights the importance of familial studies to reconcile the contradictory reports published on the pathogenicity of this variant.

Is colchicine an effective treatment in periodic fever, aphtous stomatitis, pharyngitis, cervical adenitis (PFAPA) syndrome?

PFAPA syndrome is the most frequent periodic fever syndrome in non-Mediterranean patients. The pathogenesis is unclear and the treatment is purely symptomatic and not standardized. The aim of this study was to assess colchicine's efficacy as prophylactic treatment in PFAPA syndrome and to identify factors able to predict response to treatment. We performed a retrospective, multicentric, cohort study of PFAPA patients under colchicine prophylaxis. PFAPA diagnosis was established according to Feder's criteria. Medical records were reviewed and analyzed for demographic, clinical and laboratory data. We distinguished one responder's group, defined as patients who had no more or twice fewer crises under colchicine and another one of non-responders. Subgroup analyses were performed using non-parametric Mann-Whitney test for quantitative data and calculating odds ratio and confidence interval for qualitative data. Difference between the two groups was considered significant for P-value<0.05 or a confidence interval different from 1. Twenty children, 65% of whom were boys, were analyzed. Their mean age at disease onset was 2.3±1.5 years. Among the nine responder patients, five were MEFV (71%) heterozygotes: M694V mutation in four and V726A once. Heterozygous MEFV gene mutation tended to be more frequent in the responders group (71% versus 43%; OR=0.3 [0.03-2.7]). Non-responder patients had more chronic fatigue (82% versus 33%; OR=9 [1,14-71]) and had more oral aphtosis (82% versus 11%; OR=36 [1,7-141]) than the responders ones. Although not significant, colchicine treatment appeared more effective in patients with less complete PFAPA phenotype and MEFV heterozygosity.

A novel assessment tool for clinical care of patients with autoinflammatory disease: juvenile autoinflammatory disease multidimensional assessment report.

To develop and test a new multidimensional questionnaire for assessment of children with auto-inflammatory disease (AID) such as FMF, PFAPA, HIDS, TRAPS in standard clinical care. The juvenile auto-inflammatory disease multidimensional assessment report (JAIMAR) includes 16 parent or patient-centered measures and four dimensions that assess functional status, pain, therapeutic compliance and health-related quality of life (physical, social, school, emotional status) with disease outcome. It is proposed for use as both a proxy-report and a patient self-report, with the suggested age range of 8-18 years for use as a self-report. 250 children with FMF were included in the study. Total of 179 forms were filled up by parents and patients, and 71 forms were filled up by parents having children less than 8 years. Completing and scoring the JAIMAR can be done in 15 minutes. For the JAIMAR's dimensions, the Cronbach's alpha coefficient for internal consistency was between 0.507-0.998. There was a significant and a positive correlation between the test-retest scale scores (ICC=0.607-0.966). Concerning construct validity, all factors loadings were above 0.30. For the criterion validity, the correlation level between each dimension and the related scale ranged from medium (r=0.329, p<0.0001) to large (r=0.894, p<0.0001). The parents' proxy-reported and children's self-reported data were outstandingly concordant (r=0.770-0.989). The development of the JAIMAR introduces a new and multi-dimensional approach in paediatric rheumatology practice. It is a new tool for children with auto-inflammatory dis-ease and it may help enhance their quality of care.

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.