Autoinflammatory Diseases in Childhood

The significance of carrying MEFV variants in symptomatic and asymptomatic individuals

Familial Mediterranean fever (FMF) is an autoinflammatory disease characterized by recurrent attacks of fever, serositis (peritonitis, pleuritis, or synovitis), and erysipelas-like erythema. Genetic variants in the MEFV gene are associated with this disease. Familial Mediterranean fever is considered an autosomal recessive disease. However, in Middle Eastern countries, a third of the patients expressing FMF manifestations, carry a single mutation only. Moreover, some cases of pure dominant inheritance linked to specific single MEFV variants have also been described. This complex inheritance of MEFV-associated inflammatory diseases poses a serious challenge when interpreting the results of genetic testing in patients having recurrent fever syndromes. In addition, in certain situations, asymptomatic individuals may be incidentally found to carry MEFV variants. These cases pose the question of their exact diagnosis and whether they should be treated. Previous studies have focused on genetic results interpretations among symptomatic patients. In the current article, we would like to elaborate on the genetic interpretation in cases of symptomatic individuals suspected to have FMF and on asymptomatic individuals carrying MEFV variants. We aim to assist physicians unfamiliar with FMF to cope with genetic results interpretation when facing symptomatic and asymptomatic individuals carrying MEFV variants and suggest a management plan accordingly.

Clinical characteristics of pediatric noninfectious uveitis and risk factors for severe disease: a single-center study

OBJECTIVES

We aimed to present the demographic, clinical, laboratory, and treatment data of children with non-infectious uveitis and to evaluate the risk factors for the development of complications and the need for biological treatment.

METHOD

Patients diagnosed with non-infectious uveitis in childhood and followed up for at least 1 year were included in the study. Demographic data, including age, gender, age at diagnosis, uveitis in first-degree relatives, and rheumatologic diseases, were obtained retrospectively from medical records. The presence of complications or the need for biologic therapy was considered a composite outcome suggesting severe disease.

RESULTS

The study included 123 patients (female: n = 59, 48%). The mean age at diagnosis was 14.89 ± 4.86 years. Uveitis was symptomatic in 104 patients (84.6%). Approximately one-quarter of the patients had at least one rheumatic disease (n = 35, 28.5%), the most common being juvenile idiopathic arthritis. Thirty-three patients (26.8%) had anti-nuclear antibody positivity. Biologic agents were needed in 60 patients (48.8%). Complications developed in 14 patients (11.4%). Early age at disease onset (aOR, 0.875; 95% C.I. 0.795-0.965, p = 0.007) and female gender (aOR, 2.99; 95% C.I. 1.439-6.248, p = 0.003) were significantly associated with the need for biologic treatment, while Behçet's disease (BD) was strongly associated with uveitis-related complications (aOR, 14.133; 95% C.I. 2.765-72.231, p = 0.001).

CONCLUSION

We suggest that among pediatric patients with non-infectious uveitis, females, those with an early age of disease onset, and those with BD need to be closely monitored due to a significantly increased risk of severe disease. Key Points • Limited data exist on the clinical course of non-infectious uveitis in children and the associated risk factors for severe disease. • Our study reveals that nearly a quarter of pediatric patients with non-infectious uveitis also have a rheumatic disease. • Among pediatric patients diagnosed with non-infectious uveitis, we observed an increased risk of severe disease in those with an earlier onset age, in female patients, and in those diagnosed with Behçet's disease.

Long-term safety profile and secondary effectiveness of canakinumab in pediatric rheumatic diseases: a single-center experience

BACKGROUND

To demonstrate the long-term safety profile of canakinumab over a nine-year period by documenting adverse events in patients with various pediatric rheumatic diseases.

RESEARCH DESIGN AND METHODS

This retrospective observational study was conducted at the Pediatric Rheumatology Department of Istanbul University Cerrahpasa between 2015 and 2023. The analysis concerned individuals who had been administered canakinumab treatment for at least six months. The exposure-adjusted event rates were calculated as adverse events per 100 patient days and were compared among three groups based on the cumulative canakinumab dose of <35 mg/kg, 35-70 mg/kg, and >70 mg/kg.

RESULTS

Among 189 patients, the median exposure time to canakinumab was 2.9 (1.5-4.1) years, corresponding to 573.4 patient years. The median cumulative dose of canakinumab was 2205 (1312-3600) mg. The most common adverse event was upper respiratory tract infection (0.76), followed by urinary tract infection (0.02), pneumonia (0.009), latent tuberculosis (0.009) and lymphadenitis (0.004). A total of 55 serious adverse events (0.025) were reported, 12 (0.006) of which led to drug discontinuation. The event rate of macrophage activation syndrome and disease exacerbation was statistically higher in patients receiving <35 mg/kg cumulative canakinumab dose (p < 0.05).

CONCLUSIONS

An increase in side effect was not observed with the increasing cumulative doses of canakinumab. Canakinumab demonstrated long-term safety with appropriate indication and monitoring.

A narrative review on the role of cytokines in the pathogenesis and treatment of familial Mediterranean fever: an emphasis on pediatric cases

Familial Mediterranean Fever (FMF) is a hereditary autoinflammatory disease characterized by an early onset of recurrent fever and serositis episodes. FMF is caused by mutations in the MEFV gene which encodes the pyrin protein, an IL-1β mediated inflammation regulator. Recent findings have identified a plethora of molecules and pathways involved in the regulation of inflammation and innate immunity, hence increasing our understanding of the etiology and inflammatory nature of FMF. Cytokines, in particular, have been found to play a key role in the pathogenesis and treatment of the disease. Indeed, various studies associated cytokines' genetic variations and expression with susceptibility to and severity of the disease, which was further supported by the positive response of patients, both children and adults, to targeted cytokine blocking therapies. These studies highlighted the potential use of cytokines as biomarkers and target in resistant/intolerant patients and contributed to improving the early detection of FMF in children, thus enhancing their quality of life and providing alternative treatment for severe cases. The aim of this review is to provide the latest updates on the pivotal role of cytokines in FMF and to discuss the efficacy and safety of anti-cytokine biologics by primarily focusing on pediatric FMF cases.

Examination of cardiac functions during acute attack and remission period in children with familial Mediterranean fever

Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disease characterized by recurring serosal inflammation. Cardiac involvement in FMF commonly manifests as pericarditis and pericardial effusion; however, there is limited research on myocardial function. This study aimed to assess cardiac functions during active inflammation and remission periods of FMF patients and investigate the cardiac effects of inflammation during the attack period. Thirty-eight FMF patients without additional cardiac diseases were included in the study. Demographic characteristics, clinical symptoms, family history, and MEFV gene analysis results were obtained retrospectively. Blood tests, blood pressure measurements, electrocardiogram evaluations, conventional echocardiography, and speckle tracking echocardiography were performed during the attack and remission periods. Disease severity was assessed using the Pras scoring system. During the attack period, FMF patients exhibited significantly higher leukocyte count, neutrophil count, C-reactive protein, and erythrocyte sedimentation rate compared to the remission period (p < 0.005). Speckle tracking echocardiography revealed decreased function in the inferior segments of the left ventricle during the attack period (p < 0.005). Right ventricular function was more affected in the moderate disease group. FMF patients with lymphopenia during the attack demonstrated more impaired right ventricular function compared to those with normal lymphocyte count.  Conclusions: FMF patients experience cardiac abnormalities during active inflammation, highlighting the importance of monitoring cardiac functions in these patients. Speckle tracking echocardiography can provide valuable insights into cardiac involvement in FMF. These findings emphasize the cardiac impact of FMF inflammation and the significance of long-term cardiac function monitoring in the management of FMF patients. What is Known: • The current literature lacks studies investigating myocardial function in the pediatric population during the attack period of this particular disease. • Our objective was to assess the alterations in cardiac function during the attack and remission periods, considering clinical manifestations, disease severity, acute phase reactant levels, and mutation type. We also evaluated the pattern of cardiac involvement and the affected cardiac areas by comparing remission and attack periods. What is New: • Several studies have demonstrated a rise in the prevalence of ischemic cardiac disease and mortality among individuals with FMF. • Investigating cardiac involvement during the attack period in FMF patients can provide valuable insights for the prevention of long-term complications.

Practical Approach to Diagnosis and Management of IL-1-Mediated Autoinflammatory Diseases (CAPS, TRAPS, MKD, and DIRA)

Systemic autoinflammatory diseases (SAIDs) are a group of rare genetic and nongenetic immune dysregulatory disorders associated with high morbidity and mortality if left untreated. Therefore, early diagnosis and initiation of targeted treatment is vital in SAID patients to control the disease activity and prevent long-term immune-mediated damage. A specific group of genetically defined SAIDs is associated with increased inflammasome-mediated production of active interleukin (IL)-1. Even though progress in immunobiology and genetics has brought forth diagnostic tools and novel treatments that have been described in the literature extensively, many challenges remain in the clinical setting. Some challenges that health care providers may face on a day-to-day basis include the requirement of a multidisciplinary approach due to the complexity of these diseases, limited evidence-based treatment options, and barriers to access available therapies. Primarily, IL-1 inhibitors anakinra, canakinumab, and rilonacept are used to control the inflammation in these patients, with the goal of achieving sustainable remission. Recently published provisional points to consider from the European Alliance of Associations for Rheumatology (EULAR) and American College of Rheumatology (ACR) provide diagnosis, management, and monitoring recommendations for four IL-1-mediated autoinflammatory diseases: cryopyrin-associated periodic syndromes (CAPS), tumour necrosis factor receptor-associated periodic syndrome (TRAPS), mevalonate kinase deficiency (MKD), and deficiency of the IL-1 receptor antagonist (DIRA). The goal of this paper is to aid health care professionals by providing a practical approach to diagnosis and management of these four IL-1 mediated SAIDs on the basis of the recent EULAR/ACR recommendations.

Gray zone in the spectrum of autoinflammatory diseases: familial Mediterranean fever accompanying periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome: single-center experience

Despite the advanced knowledge concerning autoinflammatory diseases (AID), more data regarding the optimal treatment options and outcomes of the children who met the criteria of more than one AID are required. This study aimed to describe the demographic and clinical characteristics of children from familial Mediterranean fever (FMF)-endemic countries who meet both the FMF and the periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome criteria. Moreover, we aimed to measure the response rates to colchicine and tonsillectomy and evaluate the factors affecting the colchicine response in these patients. The study was conducted at pediatric rheumatology tertiary centre. A total of 131 patients (58 females; 73 males) who met both the modified Marshall and pediatric FMF criteria were included. The median age at onset was 18 months (1-77 months), and the mean age at diagnosis was 47 ± 21.88 months. The median interval between episodes was 21 (7-90) days. The median disease duration was 46 (6-128) months. Consanguineous marriage was detected in 17 (13%) of the patients. The most common clinical finding was fever (100%), followed by exudative pharyngitis (88.5%), abdominal pain (86.3%), arthralgia (61.8%), stomatitis (51.1%), adenitis (42%), myalgia (28.7%), chest pain (16%), maculopapular rash (12.2%), arthritis (8.4%), and erysipelas-like rash (4.6%). MEFV gene variants were identified in 106 (80.9%) patients. The most common variants were M694V heterozygous (29%). We found that patients with tonsillopharyngitis, aphthous stomatitis, and PFAPA family history were more likely to be colchicine-resistant and tonsillectomy responsive, while those with exon 10 MEFV gene mutations were more prone to have a favorable response to colchicine.     Conclusion: PFAPA syndrome patients with exon 10 MEFV gene mutation, showing typical FMF symptoms, should be treated with colchicine, even after tonsillectomy. In multivariate analysis, PFAPA family history and lack of exon 10 MEFV gene mutations were independent risk factors for colchicine resistance. Thus, tonsillectomy may be recommended as a possible treatment option for these patients. It has yet to be clarified when colchicine treatment will be discontinued in patients whose attacks ceased after tonsillectomy that was performed due to colchicine unresponsiveness. What is Known: • A certain number of patients with periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome concomitantly fulfill the familial Mediterranean fever (FMF) criteria. • While colchicine is proposed as a first treatment choice in familial Mediterranean fever (FMF), corticosteroids are recommended as a first-line treatment in PFAPA syndrome patients. What is New: • In patients with concomitant PFAPA syndrome and FMF, PFAPA family history and lack of exon 10 MEFV gene mutation are predictive factors of colchicine resistance. • The presence of exon 10 MEFV gene mutations in patients with concomitant FMF and PFAPA syndrome has a favourable effect on response to colchicine treatment.

Curation and expansion of the Human Phenotype Ontology for systemic autoinflammatory diseases improves phenotype-driven disease-matching

Introduction

Accurate and standardized phenotypic descriptions are essential in diagnosing rare diseases and discovering new diseases, and the Human Phenotype Ontology (HPO) system was developed to provide a rich collection of hierarchical phenotypic descriptions. However, although the HPO terms for inborn errors of immunity have been improved and curated, it has not been investigated whether this curation improves the diagnosis of systemic autoinflammatory disease (SAID) patients. Here, we aimed to study if improved HPO annotation for SAIDs enhanced SAID identification and to demonstrate the potential of phenotype-driven genome diagnostics using curated HPO terms for SAIDs.

Methods

We collected HPO terms from 98 genetically confirmed SAID patients across eight different European SAID expertise centers and used the LIRICAL (Likelihood Ratio Interpretation of Clinical Abnormalities) computational algorithm to estimate the effect of HPO curation on the prioritization of the correct SAID for each patient.

Results

Our results show that the percentage of correct diagnoses increased from 66% to 86% and that the number of diagnoses with the highest ranking increased from 38 to 45. In a further pilot study, curation also improved HPO-based whole-exome sequencing (WES) analysis, diagnosing 10/12 patients before and 12/12 after curation. In addition, the average number of candidate diseases that needed to be interpreted decreased from 35 to 2.

Discussion

This study demonstrates that curation of HPO terms can increase identification of the correct diagnosis, emphasizing the high potential of HPO-based genome diagnostics for SAIDs.

The efficacy of a single-dose anakinra injection during disease attack in pediatric familial Mediterranean fever

The aim of this retrospective study is to evaluate the efficacy of a single-dose anakinra during familial Mediterranean fever (FMF) attacks and its effect on the duration, severity, and frequency of attacks. The patients with FMF who had disease episode and received a single-dose anakinra during disease episode between December 2020 and May 2022 were included. Demographic characteristics, MEFV gene variants detected, concomitant medical conditions, demographics of recent and previous episodes, laboratory findings and length of hospital stay were recorded. A retrospective analysis of medical records revealed 79 attacks from 68 patients who met inclusion criteria. The patients had a median age of 13 (2.5-25) years. All patients reported that the average duration of their previous episodes lasted longer than 24 h. When the recovery time of attacks after subcutaneous anakinra application at the disease attack was examined, it was observed that 4 attacks (5.1%) ended in 10 min; 10 attacks (12.7%) in 10-30 min; 29 attacks (36.7%) in 30-60 min; 28 attacks (35.4%) in 1-4 h; 4 attacks (5.1%) in 24 h; and 4 attacks (5.1%) ended in more than 24 h. There was no patient who did not recover from their attack after a single dose of anakinra. Although the efficacy of a single-dose anakinra administration during FMF attacks in children needs to be confirmed by prospective studies, our results suggest that use of a single-dose anakinra during FMF attacks is effective in reduction of severity and duration of disease attacks.

Early-onset recurrent panniculitis as a phenotype of NLRC4-associated autoinflammatory syndrome: Characterization of pathogenicity of the p.Ser445Pro NLRC4 variant

Monoallelic NLRC4 gain-of-function variants cause an inflammasomopathy with diverse clinical forms including infantile enterocolitis, recurrent macrophage activation syndrome, cold-induced urticaria-like lesions (or familial-cold autoinflammatory syndrome, FCAS4), and painful subcutaneous nodules. Here, we identified a large family with six consecutive generations affected. Genetic analyses detected the heterozygous p.Ser445Pro NLRC4 variant in three patients, which has been previously reported in a Dutch family with FCAS4. We aimed to describe the clinicopathological features and the functional consequences of the detected NLRC4 variant. Patients presented an early-onset (3 months-6 years) inflammatory disease characterized by recurrent panniculitis, fever and arthralgia. Histopathological examination showed perivascular and interstitial lymphohistiocytic infiltrates in the dermis and mixed panniculitis. Functional analysis supported the conclusion that the p.Ser445Pro NLRC4 variant leads to a constitutive activation of NLRC4-inflammasome and increased plasma levels of IL-18. Prompt recognition of early-onset panniculitis through clinicopathological examination and laboratory biomarkers may allow targeted therapies.

Gastrointestinal endoscopic findings of autoimmune and autoinflammatory diseases in pediatric rheumatology patients

OBJECTIVE

Rheumatic diseases in children are chronic and multisystemic diseases. In this study, it was aimed to evaluate gastrointestinal endoscopic findings in children diagnosed as autoimmune or autoinflammatory rheumatic diseases consulted with pediatric gastroenterology for gastrointestinal complaints.

METHODS

The patients followed up by the Pediatric Rheumatology Department and consulted to the Pediatric Gastroenterology Department due to gastrointestinal complaints were included in the study. File records of the patients were analyzed retrospectively.

RESULTS

A total of 28 patients were included in the study. Twelve of the patients had autoimmune disease (Juvenile idiopathic arthritis [JIA], systemic lupus erythematosus, Sjögren's syndrome, and scleroderma) and the other 16 had autoinflammatory disease (familial Mediterrnean fever, hyper Immunoglobulin D syndrome, undifferantiated systemic autoinflammatory disease, and systemic JIA). Four of the patients with familial Mediterrnean fever also diagnosed as JIA. The mean age of the patients was 11.7±3.5 years. The main gastrointestinal complaints of patients with both autoimmune and autoinflammatory diseases were abdominal pain and diarrhea. Inflammatory bowel disease was found in 33% of those with autoimmune disease and 56% of those with autoinflammatory disease in patients underwent endoscopic evaluation. M694V mutation was present in 62% of the patients with autoinflammatory disease presented with gastrointestinal complaints.

CONCLUSION

Both autoimmune and autoinflammatory rheumatic diseases can cause gastrointestinal complaints and should be referred to a pediatric gastroenterologist for early diagnosis.

Long-term efficacy of tonsillectomy/adenotonsillectomy in patients with periodic fever aphthous stomatitis pharyngitis adenitis syndrome with special emphasis on co-existence of familial Mediterranean fever

Periodic fever, aphthous stomatitis, pharyngitis, adenitis (PFAPA) syndrome is one of the most common autoinflammatory fever disorders in the childhood which may co-exists with familial Mediterranean fever (FMF) causing treatment complexity. As the role of surgery in PFAPA syndrome is still controversial, in this paper, our aim is to present our results of tonsillectomy/adenotonsillectomy in the treatment of PFAPA syndrome. Archives of a tertiary care hospital were investigated for patients who underwent tonsillectomy or adenotonsillectomy due to PFAPA Syndrome between 2010 and 2020. 344 patients were found but only 281 of them were accessible. Through phone call interview and chart review methods, preoperative and postoperative the number and severity of the attacks and general satisfaction after the operation were recorded and analyzed. Also, patients with concomitant FMF were analyzed separately. A total of 281 patients were included in the study. There was no improvement in 10 (3.55%) patients. Eight (2.84%) patients showed mild improvement, 29 (10.32%) patients had moderate improvement and 234 (83.27%) patients had full recovery after tonsillectomy. There were 266 PFAPA patients without FMF. No improvement, mild improvement, moderate improvement, and full recovery in this patient group were 5 (1.9%), 6 (2.3%), 25 (9.4%) and 230 (86.5%), respectively. FMF was present in 5.33% (15/281) of the patients. In PFAPA + FMF group 5 patients had no improvement (33.3%), 2 had mild improvement (13.3%), 4 had moderate improvement (26.7%) and 4 had full recovery (26.7%). Benefit of tonsillectomy was significantly lower in the patients with concomitant FMF when compared to the patients who did not have FMF (p < 0.001). Age of diagnosis, age of operation, severity of the disease, type of operation, and gender were found to have no significant relationship with the benefit from surgery (p < 0.05). According to the findings of this study, tonsillectomy is an effective long-term treatment for PFAPA syndrome with success rate of 83.27%. Also, preoperatively FMF should be considered in these patients, which dramatically reduces surgical efficacy.

NLRP3 gene variants and serum NLRP3 levels in periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome

OBJECTIVES

Although most of the autoinfammatory disorders have a confirmed genetic cause, periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome still has an unknown genetic background. However, familial cases of PFAPA syndrome have been reported suggesting a genetic its basis. PFAPA syndrome may also be considered an infammasome disorder as variants in infammasome-associated genes such as CARD8, NLRP3, and MEFV have been reported to contribute to the disease.

METHODS

Polymerase chain reaction (PCR)/Sanger sequencing analysis was performed for the detection of the variations in 71 PFAPA patients and 71 healthy controls. NLRP3 concentrations in serum were measured in 71 PFAPA patients and 71 healthy controls.

RESULTS

No statistically significant differences were observed in the allele or genotype frequencies of the NLRP3 polymorphisms between the controls and patients (P > 0.05). We found no significant differences for NLRP3 serum levels between PFAPA patients and controls (p > 0.05). Mutations in the MEFV gene were detected in 32.5% of our patients (13/40).

CONCLUSIONS

It seems that the synergistic effect of different genes plays a role in the formation of PFAPA syndrome. For this reason, it may be useful to examine the presence of mutations in genes such as NLRP3, MEFV, and CARD8 together while investigating the genetics of PFAPA syndrome. Key points • Familial cases of PFAPA syndrome have been reported suggesting a genetic basis for this syndrome. • Elevated serum or plasma levels of IL-1β, IL-6, and IL-18 have been demonstrated during PFAPA flares in several studies. • It seems that the synergistic effect of different genes plays a role in the formation of PFAPA syndrome.

Prediction of More Severe MEFV Gene Mutations in Childhood

Aim:

This study aimed to present the demographic, clinical, and laboratory features of children clinically diagnosed with familial Mediterranean fever (FMF) and to predict more severe mutations by evaluating those findings.

Methods:

We enrolled cases diagnosed with FMF with a defined variation in at least one allele. The medical charts of the patients were reviewed retrospectively. The patients were grouped as homozygous, compound heterozygous, and simple heterozygous cases, with and without M694V mutation. We compared the data between the subgroups using logistic regression analysis and determined the risk factors for being homozygous or compound heterozygous for M694V.

Results:

A total of 263 (M/F =109/154) cases were included. The mean age at the onset of symptoms, follow-up duration, and time to diagnosis were 6.75 ± 3.9 (0.25-17) years, 51.78 ± 39.31 (6-166) months, and 9.23 ± 14.44 (1-132) months, respectively. The rates of parental consanguinity, positive family history for FMF, and FMF in a first-degree relative were 15%, 42%, and 31.4% respectively. The most common symptom was abdominal pain (85%). There was no difference between the growth parameters of the cases during the initial and final control periods. The most frequent alleles were M694V, E148Q, and V726A. The most common accompanying disease was IgA vasculitis (20%). Almost 90% of the cases fulfilled all the defined criteria. The rate of patients having a first-degree relative with FMF was higher, Hb values were lower, and the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) values were higher during the attack period; the ESR and CRP values were higher in the attack-free period; and Pras disease severity scores were higher in homozygous or compound heterozygous cases carrying M694V. The presence of FMF in a first-degree relative increases the probability of being homozygous and compound heterozygous for M694V by a factor of 2.39; and each 1 unit increase in the Pras score increases this probability by a factor of 1.43. The threshold Pras score for this possibility is 5.5 (AUC = 0.651; 95% CI, 0.545-0.757; P = .006; sensitivity, 65%; specificity, 55%).

Conclusion:

M694V was the most common and severe mutation in our cohort. The presence of a first-degree relative with FMF and Pras scores ≥5.5 may predict a homozygous or compound heterozygous mutation for M694V.

Immunogenetics of the Ocular Anterior Segment: Lessons from Inherited Disorders

Autoimmune and autoinflammatory diseases cause morbidity in multiple organ systems including the ocular anterior segment. Genetic disorders of the innate and adaptive immune system present an avenue to study more common inflammatory disorders and host-pathogen interactions. Many of these Mendelian disorders have ophthalmic manifestations. In this review, we highlight the ophthalmic and molecular features of disorders of the innate immune system. A comprehensive literature review was performed using PubMed and the Online Mendelian Inheritance in Man databases spanning 1973-2020 with a focus on three specific categories of genetic disorders: RIG-I-like receptors and downstream signaling, inflammasomes, and RNA processing disorders. Tissue expression, clinical associations, and animal and functional studies were reviewed for each of these genes. These genes have broad roles in cellular physiology and may be implicated in more common conditions with interferon upregulation including systemic lupus erythematosus and type 1 diabetes. This review contributes to our understanding of rare inherited conditions with ocular involvement and has implications for further characterizing the effect of perturbations in integral molecular pathways.

The role of Mediterranean fever gene variants in patients with periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome

This study was conducted to investigate the relationship between clinic features and Mediterranean fever gene (MEFV) variants in patients with periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome. In total, 167 patients with PFAPA syndrome were included in the study. Female:male ratio of the patients was 0.75 (72 females, 95 males). In total 59.9% of patients with PFAPA had at least one MEFV variant and the most common heterozygous variants were M694V in 29.3% of the patients (40/167), E148Q in 8.3% (14/167), and V726A in 7.1% (12/167). The median age at the disease onset was significantly higher and the median duration of the episodes was significantly lower in patient with variants in exon 10 comparing to the others (both p = 0.01). Similarly, the median age at the disease onset was significantly higher (p = 0.01) and the median duration of the episodes was significantly lower (p = 0.04) in patient with MEFV variants than in the remaining patients. There were no significant differences according to the genotypes of the patients in terms of both treatment response and the frequency of clinical findings.Conclusion: In PFAPA syndrome, MEFV variants may be a modifier for disease onset and attack duration. What is Known: • Due to periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome having clinical findings resembling familial Mediterranean fever (FMF), it can be difficult to distinguish PFAPA syndrome and FMF especially in endemic regions for FMF. • Underlying MEFV mutations could affect the periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome's clinical presentation and response to treatment. What is New: • Having one of the underlying MEFV variants is related to later disease onset and shorter episode duration in patients with PFAPA syndrome.

Pediatric Behçet's Disease

Behçet's Disease (BD) is a systemic vasculitis firstly described as a disorder causing aphthous lesion in oral and genital mucosae and uveitis. The disease has an extremely unique distribution characterized by the highest incidence in communities living along the historical Silk road. Although our understanding of the etiopathogenesis of BD has expanded over time, there are still lots of unidentified points in the underlying mechanisms of the disease. The accepted opinion in the light of the current knowledge is that various identified and/or unidentified infectious and/or environmental triggers can take a role as a trigger in individuals with genetic susceptibility. Although the disease usually develops in young adulthood, it is reported that about 15-20% of all Behçet's patients develop in childhood. Pediatric BD differs from adult BD not only with the age of onset but also in the frequency and distribution of clinical findings, disease severity and outcome. While gastrointestinal system involvement, neurological findings, arthralgia and positive family history are more common in children, genital lesions and vascular lesions are more common in adult patients. In addition, a better disease outcome with lower severity score and activity index has been reported in children. The diagnosis of the disease is made according to clinical findings. It can be challenging to diagnose the disease due to the absence of a specific diagnostic test, and the long time interval from the first finding of the disease to the full-blown disease phenotype in pediatric cases. Therefore, many classification criteria have been proposed so far. The widely accepted ones are proposed by the International Study Group. The new sets of classification criteria which is the only one for pediatric BD were also developed for pediatric cases by the PEDBD group. The primary goal for the treatment is preventing the organ damages by suppressing the ongoing inflammation and forestalling the disease flares. The treatment of the BD can be onerous due to its multisystemic nature and a multidisciplinary approach is essential for the management of the patients. In this review article, the definition, clinical findings, epidemiology, etiopathogenesis, and treatment will be discussed.

Independent risk factors for resolution of periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome within 4 years after the disease onset

BACKGROUND/OBJECTIVE

Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome is a polygenic disease with unknown etiology. In this retrospective cohort study, we aimed to evaluate the risk factors for the resolution of PFAPA syndrome within 4 years after the onset.

METHODS

In total, 466 patients with PFAPA syndrome that are being followed up our department were included into the study. Between May 2020 and September 2020, medical charts of the patients were reviewed retrospectively.

RESULTS

The median age of the patients at the time of the study and at disease onset were 8.6 (2.9-20.5; IQR 6.9-10.6) years and 18 (1-84; IQR 11-31) months. On univariate analysis age at disease onset (p = 0.003), positive family history of PFAPA syndrome (p = 0.04), absence of myalgia (p = 0.04), and absence of headache (p = 0.003) were all associated with the resolution of PFAPA syndrome within 4 years after the onset. Multivariate logistic regression analysis revealed that age at disease onset (OR 1.04, 95% CI 1.01-1.07, p = 0.002), positive family history of PFAPA syndrome (OR 2.69, 95% CI 1.12-6.48, p = 0.02), and absence of headache (OR 0.2, 95% CI 0.05-0.74, p = 0.01) were independent risk factors for the resolution of PFAPA syndrome within 4 years after the onset.

CONCLUSION

We report later age of disease onset, positive family history of PFAPA syndrome, and absence of headache as independent risk factors for resolution of PFAPA syndrome within 4 years after the onset.

KEY POINTS

• Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome is a multifactorial disease with unknown etiology. • Although, PFAPA syndrome usually resolves within 3-5 years after the disease onset, it can persist for years and even continue into adulthood. With our current knowledge, there is no clue to predict which patients will have a long disease course and which patients will not. • Later age of disease onset, positive family history of PFAPA syndrome and absence of headache as independent risk factors for resolution of PFAPA syndrome within 4 years after the onset.

Evaluation of the thyroid disorders in children with familial Mediterranean fever

Although it is well-known that autoimmune thyroid diseases are more common in most of the autoimmune connective tissue diseases, the relationship between autoinflammatory diseases and autoimmune thyroid diseases has not well-evaluated yet and still remains unclear. The aim of this study was to investigate the frequency of autoimmune diseases of the thyroid gland and to evaluate thyroid function tests in children with familial Mediterranean fever. Thyroxine, thyroid-stimulating hormone, and thyroid autoimmune markers such as thyroid peroxidase and thyroglobulin antibodies, and thyroid ultrasound findings of 133 patients with familial Mediterranean fever and 70 healthy controls were evaluated. Serum levels of thyroid-stimulating hormone, free thyroxine, and thyroid autoimmunity markers were similar in patients with familial Mediterranean fever compared with healthy controls. There was no relationship between the duration of the disease and thyroid-stimulating hormone, free thyroxine, anti-thyroid peroxidase, and anti-thyroglobulin levels. This study revealed that incidence of thyroid dysfunction and autoimmunity is not increased in patients with familial Mediterranean fever. In conclusion, routine screening of serum thyroid function tests and thyroid antibody levels is not required in patients with familial Mediterranean fever in the absence of clinical symptoms or family history. Key Points • It is well-known that autoimmune thyroid diseases are common in autoimmune diseases. • The relationship between autoimmune thyroid diseases and autoinflammatory diseases like familial Mediterranean fever is still unclear. • In this study, we report the similar frequency of the autoinflammatory thyroid diseases in patients with familial Mediterranean fever and healthy controls. • A routine screening of serum thyroid function tests and thyroid antibody levels may not be required in patients with familial Mediterranean fever in the absence of clinical symptoms or family history.