Barron K

National Institute of Allergy and Infectious Diseases

6
Publications
43
h-index
(10,511 citations, 113 total works)

Research Topics

Inflammasome and immune disorders (42) Autoimmune and Inflammatory Disorders Research (28) Kawasaki Disease and Coronary Complications (24) Immunodeficiency and Autoimmune Disorders (11) Vasculitis and related conditions (10)

PFAPA Syndrome Publications

Features Associated with Response to Tonsillectomy in Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Cervical Adenitis Syndrome in Children.

Manthiram K, Ortega-Villa AM, Lapidus S, Bowes M, Romeo T , et al.
The Journal of pediatrics

To identify clinical features associated with response to tonsillectomy among children with periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome and to determine optimal management of children with continued episodes after tonsillectomy. Patients with PFAPA seen at Vanderbilt University Children's Hospital and the National Institutes of Health (NIH) who underwent tonsillectomy were enrolled and queried regarding symptoms before and after surgery. Ninety-seven subjects with PFAPA (43 Vanderbilt, 54 NIH) were followed for a median of 49 months following tonsillectomy. Nearly half of participants reported complete resolution of PFAPA episodes (65% at Vanderbilt and 35% at NIH), while 25% had less severe or frequent episodes, 23% had a period of remission with recurrence, and 4% had no change in episodes. By logistic regression, factors associated with a full response to tonsillectomy were episode resolution with glucocorticoid treatment, presence of exudative pharyngitis, absence of rash, and absence of arthralgia/myalgia during pre-tonsillectomy PFAPA flares. Among those requiring treatment for persistent flares post-tonsillectomy, 15/19 (79%) reported improvement with cimetidine or famotidine prophylaxis. Tonsillectomy remains effective in improving PFAPA flares in most patients. However, unique episode features prior to tonsillectomy appear to be clinical predictors of response to tonsillectomy. Histamine receptor 2 antagonists like cimetidine were effective prophylactic agents for refractory cases post-tonsillectomy. Patients with incomplete response to tonsillectomy may represent a subset of PFAPA with unique factors affecting their pathogenesis.

Common genetic susceptibility loci link PFAPA syndrome, Behçet's disease, and recurrent aphthous stomatitis.

Manthiram K, Preite S, Dedeoglu F, Demir S, Ozen S , et al.
Proceedings of the National Academy of Sciences of the United States of America

Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome is the most common periodic fever syndrome in children. The disease appears to cluster in families, but the pathogenesis is unknown. We queried two European-American cohorts and one Turkish cohort (total = 231) of individuals with PFAPA for common variants previously associated with two other oropharyngeal ulcerative disorders, Behçet's disease and recurrent aphthous stomatitis. In a metaanalysis, we found that a variant upstream of (rs17753641) is strongly associated with PFAPA (OR 2.13, = 6 × 10). We demonstrated that monocytes from individuals who are heterozygous or homozygous for this risk allele produce significantly higher levels of IL-12p70 upon IFN-γ and LPS stimulation than those from individuals without the risk allele. We also found that variants near , , and were significant susceptibility loci for PFAPA, suggesting that the pathogenesis of PFAPA involves abnormal antigen-presenting cell function and T cell activity and polarization, thereby implicating both innate and adaptive immune responses at the oropharyngeal mucosa. Our results illustrate genetic similarities among recurrent aphthous stomatitis, PFAPA, and Behçet's disease, placing these disorders on a common spectrum, with recurrent aphthous stomatitis on the mild end, Behçet's disease on the severe end, and PFAPA intermediate. We propose naming these disorders Behçet's spectrum disorders to highlight their relationship. alleles may be factors that influence phenotypes along this spectrum as we found new class I and II associations for PFAPA distinct from Behçet's disease and recurrent aphthous stomatitis.

Classification criteria for autoinflammatory recurrent fevers.

Gattorno M, Hofer M, Federici S, Vanoni F, Bovis F , et al.
Annals of the rheumatic diseases

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).

Vanoni F, Federici S, Antón J, Barron KS, Brogan P , et al.
Pediatric rheumatology online journal

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.

Physicians' perspectives on the diagnosis and management of periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome.

Manthiram K, Li SC, Hausmann JS, Amarilyo G, Barron K , et al.
Rheumatology international

To assess the practice patterns of pediatric rheumatology and infectious diseases subspecialists in the diagnosis and treatment of periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome. An online survey assessing diagnostic and treatment approaches was sent to 424 members of the Childhood Arthritis and Rheumatology Research Alliance (CARRA) and 980 members of the Pediatric Infectious Disease Society (PIDS). 277 physicians (123 from CARRA and 154 from PIDS representing 21% of the total membership) completed the survey. To diagnose PFAPA, most respondents agreed that patients must have the following features of the diagnostic criteria: stereotypical fever episodes (95%), asymptomatic intervals between episodes (93%), and normal growth and development (81%). However, 71% of the respondents did not require age of onset <5 years, 33% did not require regular intervals between episodes, and 79% did not require the concomitant signs of aphthous stomatitis, adenitis, or pharyngitis during episodes as long as episodes were regular. Over half (58%) considered episode resolution with steroids to be diagnostic of PFAPA. Corticosteroids, antipyretics, tonsillectomy, and cimetidine were the most commonly prescribed treatments, while steroids and tonsillectomy were most effective. Subspecialists in pediatric rheumatology and infectious diseases showed limited adherence to the complete published criteria for diagnosing PFAPA suggesting heterogeneity in the characteristics of patients diagnosed with the disorder. These findings emphasize the need to develop consensus diagnostic and treatment guidelines in well-characterized patient populations.

Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) is a disorder of innate immunity and Th1 activation responsive to IL-1 blockade.

Stojanov S, Lapidus S, Chitkara P, Feder H, Salazar JC , et al.
Proceedings of the National Academy of Sciences of the United States of America

The syndrome of periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) is the most common periodic fever disease in children. However, the pathogenesis is unknown. Using a systems biology approach we analyzed blood samples from PFAPA patients whose genetic testing excluded hereditary periodic fevers (HPFs), and from healthy children and pediatric HPF patients. Gene expression profiling could clearly distinguish PFAPA flares from asymptomatic intervals, HPF flares, and healthy controls. During PFAPA attacks, complement (C1QB, C2, SERPING1), IL-1-related (IL-1B, IL-1RN, CASP1, IL18RAP), and IFN-induced (AIM2, IP-10/CXCL10) genes were significantly overexpressed, but T cell-associated transcripts (CD3, CD8B) were down-regulated. On the protein level, PFAPA flares were accompanied by significantly increased serum levels of chemokines for activated T lymphocytes (IP-10/CXCL10, MIG/CXCL9), G-CSF, and proinflammatory cytokines (IL-18, IL-6). PFAPA flares also manifested a relative lymphopenia. Activated CD4(+)/CD25(+) T-lymphocyte counts correlated negatively with serum concentrations of IP-10/CXCL10, whereas CD4(+)/HLA-DR(+) T lymphocyte counts correlated positively with serum concentrations of the counterregulatory IL-1 receptor antagonist. Based on the evidence for IL-1β activation in PFAPA flares, we treated five PFAPA patients with a recombinant IL-1 receptor antagonist. All patients showed a prompt clinical and IP-10/CXCL10 response. Our data suggest an environmentally triggered activation of complement and IL-1β/-18 during PFAPA flares, with induction of Th1-chemokines and subsequent retention of activated T cells in peripheral tissues. IL-1 inhibition may thus be beneficial for treatment of PFAPA attacks, with IP-10/CXCL10 serving as a potential biomarker.